Medium conveying device and medium processing system using the same

Abstract

To easily achieve improved stable conveyability and charge removal efficiency of a medium during conveyance of a charged medium by effectively preventing adhesion of the medium during a cooling process with a simple configuration compared to methods that perform charge removal before or after cooling the medium.SOLUTION: A medium conveying device 11 comprises: first belt-like conveying means 1 that contacts one side of a medium S and conveys it, and second belt-like conveying means 2 that faces and contacts the first conveying means 1 and holds and conveying the medium S in a contact region CN between it and the first conveying means 1; cooling means 3 that is provided to at least one of the first conveying means 1 and the second conveying means 2, and cools the medium S in the contact region CN; and discharging means 4 for discharging the medium S passing through the contact region CN by applying a discharging voltage to the first conveying means 1 or the second conveying means 2. A medium processing system including the medium conveying device is also an object of the invention.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a medium transport device and a medium processing system using the same. [Background technology]

[0002] As conventional medium transport devices or medium processing systems, those described in Patent Documents 1 to 3, for example, are already known. Patent document 1 discloses an image forming apparatus including a charge removal section that removes static electricity from paper after fixing processing, and a cooling section that is provided at least either above or below the charge removal section and that cools the paper that has been charge removed by the charge removal section. Patent Document 2 discloses a belt transfer device equipped with air blowing means for blowing air onto a separation portion when a transfer paper is separated from a transfer belt. Patent document 3 discloses an image forming apparatus that includes an output tray onto which paper that has been fixed by a fixing section is discharged, a blower section that blows air from inside the device onto the paper discharged onto the output tray, and a static elimination unit that is provided between the output tray and the blower section and that eliminates static electricity from the paper discharged onto the output tray using constant voltage control, wherein the blower section directs at least a portion of the air blown onto the output tray onto a pair of static elimination rollers of the static elimination unit, thereby lowering the resistance value of the pair of static elimination rollers and increasing the current value, thereby enabling the static elimination performance of the static elimination unit to be maintained. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-090564 A (Form for carrying out the invention, FIG. 6) [Patent Document 2] JP 10-268666 A (Embodiment of the invention, Fig. 1) [Patent Document 3] JP 2017-039599 A (Form for carrying out the invention, FIG. 2) Summary of the Invention [Problem to be solved by the invention]

[0004] The technical problem that the present invention aims to solve is to provide a media conveying device and a media processing system using the same that, when transporting charged media, has a simple configuration that effectively prevents the media from sticking during cooling processing, and easily achieves stable media transportability and improved de-electrification efficiency, compared to a configuration in which de-electrification processing is performed before or after cooling the media. [Means for solving the problem]

[0005] A first technical feature of the present invention is a medium conveying device comprising: a belt-shaped first conveying means that contacts one side of a medium to convey the medium; a belt-shaped second conveying means that contacts and faces the first conveying means and conveys the medium by clamping it in a contact area between the first conveying means and the second conveying means; a cooling means that is provided on at least one of the first conveying means or the second conveying means and cools the medium in the contact area; and a discharge means that discharges the medium passing through the contact area by applying a discharge voltage to the first conveying means or the second conveying means.

[0006] A second technical feature of the present invention is a media conveying device having the first technical feature, characterized in that the cooling means cools the back surface of the contact area of ​​the first conveying means or the second conveying means. A third technical feature of the present invention is a media conveying device having the second technical feature, characterized in that the cooling means is composed of a heat dissipation means in contact with the back surface of the contact area. A fourth technical feature of the present invention is a medium conveying device having the first technical feature, characterized in that the discharge means applies a discharge voltage to a part of a tension member of the first conveying means or the second conveying means, and applies a discharge voltage to the first conveying means or the second conveying means. A fifth technical feature of the present invention is a medium conveying device having the fourth technical feature, characterized in that the discharge means uses a driving tension member as the tension member to which the discharge voltage is applied. A sixth technical feature of the present invention is a medium conveying device having the fourth technical feature, characterized in that the de-ionization means uses a tension member located at the exit of the contact area in the direction of movement of the medium as a tension member to which the de-ionization voltage is applied. A seventh technical feature of the present invention is a medium conveying device having the first technical feature, characterized in that the discharge means variably sets the polarity and output value of the discharge voltage. An eighth technical feature of the present invention is a media conveying device having the seventh technical feature, characterized in that the discharge means has a detection means for detecting the charged state of the medium before it enters the contact area, and the polarity and output value of the discharge voltage are variably set depending on the detection result of the detection means. A ninth technical feature of the present invention is a media conveying device having the seventh technical feature, characterized in that the discharge means has a discrimination means for discriminating characteristic information of the medium before it enters the contact area, and the polarity and output value of the discharge voltage are variably set depending on the discrimination result of the discrimination means.

[0007] A tenth technical feature of the present invention is a medium conveying device having the first technical feature, characterized in that the first conveying means and the second conveying means are made of a conductive member having a volume resistivity of 11 Log Ω cm or less under a voltage application condition of 500 V / thickness of 100 μm. An eleventh technical feature of the present invention is a media conveying device having the first technical feature, characterized in that the first conveying means and the second conveying means are arranged such that the shape of the inlet portion leading to the contact area along the movement direction of the medium is deformed into a shape that can correct curling of the medium. A twelfth technical feature of the present invention is a media conveying device having the first technical feature, characterized in that the first conveying means and the second conveying means have a discharge section consisting of a pair of tension members at an exit of the contact area in the direction of movement of the media, and this discharge section is provided with a discharge posture variable means for varying the discharge angle of the media relative to a predetermined reference line. A thirteenth technical feature of the present invention is a media transport device having the twelfth technical feature, characterized in that the discharge attitude variable means has a discrimination means for discriminating the type or characteristic information of the medium before it enters the contact area, and the discharge angle of the medium is variably set depending on the discrimination result of this discrimination means. A fourteenth technical feature of the present invention is a media conveying device having the first technical feature, characterized in that the cooling means has a cooling variable means for varying the degree of cooling of the media passing through the contact area. A fifteenth technical feature of the present invention is a media conveying device having the first technical feature, characterized in that the first conveying means and the second conveying means have a speed variable means for varying the conveying speed of the media passing through the contact area. A 16th technical feature of the present invention is a medium transport device having the first technical feature, characterized in that it further comprises a non-contact de-electrification means that is provided downstream of the exit of the contact area in the transport direction of the medium, arranged in a non-contact state with respect to the medium discharged from the contact area, and further de-electrifies the medium by corona discharge obtained by applying a discharge voltage including at least an AC component to a discharge electrode.

[0008] A 17th technical feature of the present invention is a media processing system comprising: a processing means for performing a process involving charging a moving medium; and a media conveying device having any of the first to sixteenth technical features, which is disposed downstream of the processing means in the direction of movement of the medium and cools the medium while removing static electricity by passing the medium through the medium. An 18th technical feature of the present invention is a media processing system having the 17th technical feature, characterized in that the processing means comprises an image creating means for creating an image on an image holding means and transferring the created image to the medium using a transfer electric field, and a fixing means for heating and fixing the image transferred to the medium. Effect of the Invention

[0009] According to the first technical feature of the present invention, when transporting a charged medium, compared to an embodiment in which the de-electrification process is performed before or after cooling the medium, a simple configuration can effectively prevent the medium from sticking during the cooling process, and it is easy to achieve stable transportability of the medium and improved de-electrification efficiency. According to the second technical feature of the present invention, it is possible to improve the cooling efficiency for the medium passing through the contact area, compared to the case where areas other than the contact area between the first transport means and the second transport means are cooled. According to the third technical feature of the present invention, the rear surface of the contact area can be efficiently cooled with a simple configuration. According to a fourth technical feature of the present invention, the static elimination means can be easily produced by utilizing a part of the tension member constituting the first conveying means or the second conveying means. According to a fifth technical feature of the present invention, by adding a detection means for detecting when the medium enters the contact area between the first transport means and the second transport means, it is possible to operate the static elimination means when the medium enters, thereby prolonging the life of the static elimination means against electrical deterioration over time. According to the sixth technical feature of the present invention, it is possible to efficiently apply the static elimination voltage to the contact area through which the medium passes, without affecting the entry operation of the medium into the contact area. According to the seventh technical feature of the present invention, the voltage applied to the charge removing means can be varied depending on the charged state of the medium, and the charge removing voltage can be appropriately set. According to the eighth technical feature of the present invention, the charged state of the medium can be accurately grasped, the applied level of the charge removing means can be made variable depending on the charged state of the medium, and the charge removing voltage can be appropriately set. According to a ninth technical feature of the present invention, by adding a discrimination means for discriminating characteristic information such as the type and thickness of the medium, it is possible to make the application level of the static elimination means variable depending on the characteristic information of the medium, and to appropriately set the static elimination voltage. According to the tenth technical feature of the present invention, the static elimination voltage from the static elimination means can be appropriately applied to the first conveying means and the second conveying means, compared to when the first conveying means and the second conveying means are constructed of insulating materials. According to the eleventh technical feature of the present invention, even if the medium has curl, the curl of the medium can be straightened while the medium passes through the transfer area. According to the twelfth technical feature of the present invention, the running of the medium that has passed through the contact area can be stabilized compared to a case where no discharge attitude varying means is provided. According to the thirteenth technical feature of the present invention, the ejection attitude of the medium passing through the contact area can be appropriately adjusted depending on the type of medium. According to the fourteenth technical feature of the present invention, even if the heating state of the medium changes depending on the characteristics of the medium or the processing conditions for the medium, the medium can be appropriately cooled in accordance with the heating state. According to the fifteenth technical feature of the present invention, even if the heating state or charging state of the medium changes depending on the characteristics of the medium or the processing conditions for the medium, the medium can be appropriately cooled or de-electrified by adjusting the cooling time or de-electrification time. According to the 16th technical feature of the present invention, the static elimination process by the static elimination means employs a method of eliminating static electricity by applying a charge of a polarity opposite to the charged polarity of the medium, and even if the static elimination level is insufficient, the static elimination level can be further reduced to make it more uniform. According to the 17th technical feature of the present invention, when transporting a charged medium, it is possible to easily construct a medium processing system including a medium transporting device that has a simple configuration and can effectively prevent the medium from sticking during the cooling process, and can easily achieve stable medium transportability and improved de-electrification efficiency, compared to an embodiment in which the de-electrification process is performed before or after cooling the medium. According to the 18th technical feature of the present invention, in a media processing system having an image creating means and a fixing means as processing means, the media to which an image has been transferred is heated in a charged state, but the media can be cooled while being efficiently de-electrified, and an image can be properly formed on the media. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1A is an explanatory diagram showing an overview of an embodiment of a media processing system including a media conveying device to which the present invention is applied, and FIG. 1B is an explanatory diagram showing the structure around the discharge section of the media conveying device in FIG. [Diagram 2] 1 is an explanatory diagram showing the overall configuration of a media processing system according to a first embodiment. [Diagram 3] 3 is an explanatory diagram showing a main part of a medium transport system subsequent to a transfer unit in the medium processing system shown in FIG. 2. [Figure 4] FIG. 2 is an explanatory diagram showing details of the cooling device and its surroundings according to the first embodiment. [Diagram 5] FIG. 4A is an explanatory diagram showing a configuration example of a discharge section of a cooling device, and FIG. 4B is an explanatory diagram showing a configuration example of a steering mechanism of the cooling device. [Figure 6] 4 is a flowchart showing a control process of the cooling device according to the first embodiment. [Figure 7] FIG. 4 is an explanatory diagram showing the operation of the cooling device according to the first embodiment. [Figure 8] FIG. 4 is an explanatory diagram showing the relationship between electrical resistance and relative humidity. [Figure 9] (a) is an explanatory diagram showing the behavior when the discharge angle of the medium at the discharge section is θ=0, (b) is an explanatory diagram showing the behavior when the discharge angle is θ(-), and (c) is an explanatory diagram showing the behavior when the discharge angle is θ(+). [Figure 10] FIG. 11 is an explanatory diagram showing a main part around a cooling device according to a second embodiment. [Figure 11] FIG. 11 is an explanatory diagram showing the relationship between the type of medium and the discharge angle of the medium at a discharge part of the cooling device in the cooling device according to the second embodiment. [Figure 12]FIG. 10(a) is an explanatory diagram showing a configuration example of a discharge part of a cooling device according to a second embodiment, and (b) is a view taken along the arrow B in (a). [Figure 13] FIG. 11 is an explanatory diagram showing a main part of a cooling device according to a third embodiment. [Figure 14] (a) is an explanatory diagram showing an example of the configuration of a curl correction mechanism, (b) is an explanatory diagram showing the behavior of the curl correction mechanism, (c) is an explanatory diagram showing the behavior of the curl correction mechanism when the leading edge of the medium has an upper curl, and (d) is an explanatory diagram showing the behavior of the curl correction mechanism when the leading edge of the medium has a lower curl. [Figure 15] FIG. 11 is an explanatory diagram showing details of a cooling device and its surroundings according to a fourth embodiment. [Figure 16] FIG. 1(a) is a graph showing the relationship between the media thickness t and the media discharge angle θ when the media peeling operation from the discharge section is stably performed when the media feed speed is 250 mm / s in the cooling device of Example 1, and FIG. 1(b) is a graph showing the relationship between the media thickness t and the media discharge angle θ performed in the same manner as in FIG. 1(a) when the media feed speed is 500 mm / s. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Overview of the embodiment FIG. 1(a) shows an overview of an embodiment of a media processing system including a media transport device to which the present invention is applied. In the same figure, the media processing system comprises a processing means 10 that performs processing involving charging a moving media S, and a media transport device 11 that is located downstream of the processing means 10 in the direction of movement of the media S and cools the media S while removing static electricity by passing it through. Here, the processing means 10 may include, for example, an image forming means for creating an image on an image holding means and transferring the created image to a medium S using a transfer electric field, and a fixing means for heating and fixing the image transferred to the medium S.

[0012] The medium conveying device 11 includes a belt-like first conveying means 1 that contacts one side of the medium S to convey the medium S, a belt-like second conveying means 2 that faces and contacts the first conveying means 1 and conveys the medium S by clamping it in a contact area CN between the first conveying means 1 and the second conveying means 2, a cooling means 3 that is provided on at least one of the first conveying means 1 or the second conveying means 2 and cools the medium S in the contact area CN, and a discharge means 4 that discharges the medium S passing through the contact area CN by applying a discharge voltage to the first conveying means 1 or the second conveying means 2.

[0013] In such technical means, the media processing system may have the processing means 10 and the media transport device 11 in a single device housing, or the device including the processing means 10 and the device including the media transport device 11 may be configured as separate units and connected together. Also, the medium conveying device 11 is characterized in that the first conveying means 1 and the second conveying means 2 are both belt-shaped, and either of the conveying means is equipped with at least a cooling means 3, and a static electricity removal function is added to this. Therefore, while in the previous example, when conveying the medium, the cooling function and the static electricity removal function were performed by separate devices, it is no longer necessary to separately provide a cooling device with a cooling function and a static electricity removal device with a static electricity removal function.

[0014] Furthermore, the cooling means 3 may be provided in at least one of the first conveying means 1 or the second conveying means 2. Here, when the cooling means 3 is provided in one of them (for example, the first conveying means), the other conveying means (for example, the second conveying means) where the cooling means 3 is not provided is indirectly cooled through the contact area CN when the medium S does not pass through. Furthermore, the cooling means 3 is typically a heat sink arranged in contact with the back surface of the contact area CN of the first conveying means 1 or the second conveying means 2, but is not limited thereto, and may be configured to cool a portion (either the back surface or the front surface) other than the contact area CN of the first conveying means 1 or the second conveying means 2. In this case, the cooling means 3 may be, for example, a cooling element (such as a Peltier element) incorporated in the tension member 5 or 6 of the first conveying means 1 or the second conveying means 2, so that the tension member 5 or 6 also serves as the cooling means 3. Furthermore, the cooling means 3 used in this example has the requirement of "cooling the medium S in the contact area CN," and does not include aspects such as cooling the medium S by blowing air on the medium S that has not entered the contact area CN.

[0015] The static elimination means 4 may be appropriately selected as long as it applies a static elimination voltage to the first conveying means 1 or the second conveying means 2. In this case, the static elimination voltage may be applied directly to the first conveying means 1 or the second conveying means 2. Alternatively, a tension member or an electrode member of the first conveying means 1 or the second conveying means 2 may be separately provided, the static elimination voltage may be applied to this, and the static elimination voltage may be applied to the first conveying means 1 or the second conveying means 2 via the tension member or the electrode member. Furthermore, the static electricity removing means 4 in this embodiment removes static electricity while cooling the medium S. If the temperature is lowered under the same absolute humidity, the relative humidity increases, so that static electricity tends to dissipate in a short time. This promotes the static electricity removing action by the static electricity removing means 4.

[0016] Next, a representative or preferred embodiment of the medium conveying device according to the embodiment will be described. First, a representative embodiment of the cooling means 3 is one that cools the back surface of the contact area CN of the first conveying means 1 or the second conveying means 2. This embodiment is, for example, configured with heat dissipation means (such as a heat sink) that contacts the back surface of the contact area CN. A preferred embodiment of the cooling means 3 includes an embodiment having a cooling variable means (not shown) that varies the degree of cooling for the medium S passing through the contact area CN. This example is preferable in that the degree of cooling can be appropriately adjusted according to the heating state of the medium S even if the heating state of the medium S changes due to changes in the surrounding environment or processing conditions for the medium S.

[0017] 1(b), a representative embodiment of the static elimination means 4 is to apply a static elimination voltage to the tension member 5a, which is one of the tension members 5 of the first conveying means 1 (or the tension member 6a, which is one of the tension members 6 of the second conveying means 2), and to apply a static elimination voltage to the first conveying means 1 (or the second conveying means 2). This embodiment is effective in that the tension member 5 or 6 of the first conveying means 1 or the second conveying means 2 is used as an electrode member, and there is no need to provide a separate electrode member. In particular, from the viewpoint of activating the static elimination means 4 at the timing when the medium S enters the contact area CN, it is preferable to use a driving tension member as the tension member 5a (or 6a) to which the static elimination voltage is applied. In addition, in this example, from the viewpoint of not affecting the entry operation of the medium S into the contact area CN, it is preferable to use a tension member located at the exit of the contact area CN in the direction of movement of the medium S as the tension member 5a (or 6a) to which the static electricity removal voltage is applied.

[0018] In addition, a preferred embodiment of the static elimination means 4 is one in which the polarity and output value of the static elimination voltage are variably set. This embodiment is effective in implementing a static elimination operation suited to the charged body of the medium S, since the charged state of the medium S varies. In particular, in order to grasp the charged state of the medium S in advance, for example, a detection means not shown in the figure may be provided for detecting the charged state (charge polarity, charge amount) of the medium S before it enters the contact area CN, and the polarity and output value of the static elimination voltage may be variably set depending on the detection result of the detection means. In addition, since the charged state of the medium S also depends on the type or characteristic information (thickness, resistance value, etc.) of the medium S, it is also possible to have a discrimination means (not shown) that discriminates the characteristic information of the medium S before it enters the contact area CN, and to variably set the polarity and output value of the static elimination voltage depending on the discrimination result of the discrimination means.

[0019] Furthermore, the material properties of the first conveying means 1 or the second conveying means 2 may be appropriately selected, but from the viewpoint of maintaining good static elimination performance in the contact area CN, it is preferable that the first conveying means 1 and the second conveying means 2 are made of a conductive material having a volume resistivity of 11 Log Ω·cm or less under a voltage application condition of 500 V / thickness of 100 μm. Also, another function may be given to the first transport means 1 and the second transport means 2. For example, to give them a curl correction function, the first transport means 1 and the second transport means 2 may be arranged such that the shape of the inlet of the contact area CN along the moving direction of the medium S is deformed into a shape that can correct the curl of the medium S.

[0020] Furthermore, a preferred embodiment of the first conveying means 1 and the second conveying means 2 includes an embodiment in which, as shown in Figure 1(b), a discharge section 7 consisting of a pair of tension members 5a, 6a is provided at the exit of the contact area CN in the direction of movement of the medium S, and this discharge section 7 is provided with a discharge attitude variable means 8 that varies the discharge angle θ of the medium S relative to a predetermined reference line. Here, a representative embodiment of the discharge attitude variable means 8 is one having a discrimination means (not shown) that discriminates characteristic information of the medium S before it enters the contact area CN, and variably sets the discharge angle θ of the medium S depending on the discrimination result of this discrimination means.

[0021] In addition, a preferred embodiment of the first transport means 1 and the second transport means 2 includes an embodiment having a speed varying means (not shown) that varies the transport speed of the medium S passing through the contact area CN. This example is effective in that even if the heating state or charging state of the medium S changes, the medium S can be appropriately cooled and de-electrified by adjusting the cooling time and de-electrification time. Furthermore, from the viewpoint of strengthening the static electricity removal effect on the medium S, a preferred embodiment is one in which a non-contact static electricity removal means (not shown) is provided downstream of the exit of the contact area CN in the transport direction of the medium S. The non-contact static electricity removal means referred to here refers to a means that is disposed in a non-contact state with the medium S discharged from the contact area CN, and further removes static electricity from the medium S by corona discharge obtained by applying a discharge voltage containing at least an AC component to a discharge electrode.

[0022] First embodiment Hereinafter, the present invention will be described in more detail based on the embodiments shown in the accompanying drawings. FIG. 2 shows the overall configuration of the media processing system according to the first embodiment. -Overall configuration of media processing system- In this embodiment, the medium processing system 20 is an image forming system that forms an image on a medium S and discharges it. This medium processing system 20 has a housing 21 that houses a plurality of (four in this example) image forming units 30 that form images of each color component (four colors in this example: yellow (Y), magenta (M), cyan (C), and black (K)), a transfer device 40 that transfers each image formed in each image forming unit 30 onto a medium S, such as paper, a fixing device 50 that fixes an unfixed image transferred onto the medium S by the transfer device 40, and a medium transport system 60 that transports the medium S to each processing unit such as the transfer device 40 and the fixing device 50.

[0023] -Image forming section- In this example, the image forming unit 30 (specifically, 30a to 30d) employs an electrophotographic method and includes, for example, a drum-shaped photoconductor 31, a charger 32 which charges the surface of the photoconductor 31 to a predetermined potential, an exposure unit 33 which exposes the photoconductor 31 charged by the charger 32 based on image data and writes an electrostatic latent image onto it, a developing unit 34 which develops the electrostatic latent image formed on the photoconductor 31 with toner of each color component, and a cleaning unit 35 which cleans off toner and the like remaining on the photoconductor 31 after transfer. In this example, an electrophotographic system is shown, but the present invention is not limited to this system. It is also possible to use a system in which a dielectric is used instead of the photosensitive member 31 and an electrostatic latent image is written on the dielectric by a latent image writer such as an ion flow writer.

[0024] -Transfer device- The transfer device 40 may employ a direct transfer method in which an image (color component image) made of toner of each color component formed in each image forming section 30 is directly transferred to the medium S, but in this example, an indirect transfer method is employed. In this example, the transfer device 40 is arranged to be circulatable opposite each photoconductor 31 of each image forming section 30, and includes an intermediate transfer body 41, for example in the form of a belt, which transfers and holds each color component image formed on each photoconductor 31, primary transfer devices 42, which are respectively arranged on the back surface of the intermediate transfer body 41 opposite each photoconductor 31, and which primarily transfers the color component image on each photoconductor 31 onto the intermediate transfer body 41, and a secondary transfer device 43 which collectively transfers (secondarily transfers) each color component image transferred and superimposed onto the intermediate transfer body 41 onto the medium S.

[0025] In this example, the belt-shaped intermediate transfer body 41 is stretched around a plurality of tension rolls 45, and is driven to be circulatively movable, for example, with one (45a) of the tension rolls 45 as a driving roll. The primary transfer device 42 is provided with, for example, a primary transfer roll on the back surface of the intermediate transfer body 41 facing the photoreceptor 31, and applies a predetermined primary transfer bias to the primary transfer roll, thereby forming a primary transfer electric field for image transfer. The secondary transfer device 43 is provided with, for example, a secondary transfer roll 43a on the surface of the intermediate transfer body 41, at a position facing one (45b) of the tension rolls 45, and applies a predetermined secondary transfer bias to the tension roll 45b facing the secondary transfer roll 43a, thereby forming a secondary transfer electric field for image transfer in the secondary transfer region TR between the secondary transfer roll 43a and the tension roll 45b. In this example, a corona discharger such as a corotron or a scorotron may be used for the primary transfer device 42 or the secondary transfer device 43. In addition, in the secondary transfer device 43, a transfer belt stretched around a transfer roll may be used in consideration of the transportability of the medium S. Incidentally, reference numeral 46 denotes an intermediate transfer body cleaner for cleaning the intermediate transfer body 41 toner and the like remaining thereon.

[0026] - Fixing device - As the fixing device 50, as long as it fixes the unfixed image on the medium S, it may be of a contact type that contacts the unfixed image or a non-contact type, and the fixing method may be appropriately selected from a heat and pressure method, a heating method, etc. In this example, a fixing device 50 employing a contact type heating and pressurizing method is used. As shown in Fig. 2 and Fig. 3, the fixing device 50 includes a fixing belt 51 made of a heat-resistant material that moves in a circulating manner, a pressure roll 52 arranged in contact with a surface portion of the fixing belt 51 that faces the fixing zone, a pressure pad 53 arranged in contact with a back surface of the fixing belt 51 that faces the pressure roll 52 and serves as a pressing member that forms a fixing zone FR in which the medium S is sandwiched and conveyed between the pressure roll 52 and the fixing belt 51, a heating roll 54 that stretches the fixing belt 51 in a circulating manner on the upstream side of the fixing zone FR of the fixing belt 51 in the moving direction and contacts and heats the fixing belt 51, and a tension roll 55 that stretches the fixing belt 51 in a circulating manner on the downstream side of the fixing zone FR of the fixing belt 51 in the moving direction.

[0027] Here, the fixing belt 51 may be appropriately selected, but a heat-resistant resin material, for example, polyimide (PI) resin, is used as the base material, and an elastic layer of silicone rubber or the like is laminated on the surface of the base material, and a release layer of fluorine-based resin is also laminated on the surface of the base material. The pressure roll 52 is made of a metal roll with an elastic material such as urethane rubber laminated around it, and a protective layer is laminated on the surface of the elastic material. Furthermore, the pressure pad 53 functions as a receiving member that is placed in contact with the back surface of the fixing belt 51, and has a plate-shaped pad body made of a liquid crystal polymer or the like, and a holder consisting of a roughly rectangular hollow pipe that holds it.

[0028] The heating roll 54 has a heat source such as a halogen lamp built in the roll body, and both ends of the roll body are rotatably supported by bearings (not shown). The heating roll 54 transfers heat to the fixing belt 51 by bringing the peripheral surface of the roll body into contact with the rear surface of the fixing belt 51, heating the fixing belt 51 for fixing processing in the fixing zone FR. Furthermore, in this example, the heating roll 54 functions as a drive roll that rotates the fixing belt 51. Therefore, in this example, the pressure roll 52 rotates following the fixing belt 51 in the fixing zone FR. Incidentally, the heating roll 54 may be configured such that, instead of a heat source such as a halogen lamp, a heat generating resistive layer is formed on the roll body via an insulating layer, and the heat generating resistive layer is heated.

[0029] The tension roll 55 may be any roll that stretches the fixing belt 51 so as to be able to circulate, but may also function as a tension roll that applies tension from the viewpoint of maintaining the tension of the fixing belt 51. If it is necessary to further increase the amount of heat applied to the fixing belt 51, a heat source may be incorporated in the tension roll 55 or the above-mentioned pressing pad 53. In this embodiment, the fixing device 50 employs a fixing belt 51, but this is not limited to this, and it is of course possible to appropriately select an embodiment such as one in which a heating roll and a pressure roll are arranged opposite each other.

[0030] - Media transport system - 2, the medium transport system 60 has a plurality of stages (two stages in this example) of medium supply containers 61 (61a, 61b), and transports the medium S supplied by a feeder 62 from one of the medium supply containers 61 from a vertical transport path 63 extending in a substantially vertical direction to a horizontal transport path 64 extending in a substantially horizontal direction. This horizontal transport path 64 reaches a secondary transfer area TR, and then transports the medium S on which the transferred image is held to a fixing site by the fixing device 50 via a transport belt 65, and discharges the medium S after fixing from the discharge port 22 of the housing 21 to a medium discharge receiver (not shown) provided on the side.

[0031] The medium transport system 60 has a branched transport path 66 that branches downward from a portion of the horizontal transport path 64 located downstream of the fixing device 50 in the medium transport direction, and a switching gate 67 for switching the transport path is provided at the boundary between the horizontal transport path 64 and the branched transport path 66. The medium transport system 60 has an inversion section 68 in the middle of the branched transport path 66 where the medium S can be inverted, and the medium S inverted at the inversion section 68 is returned from the vertical transport path 63 to the horizontal transport path 64 via a return transport path 69. Therefore, the medium transport system 60 transports the inverted medium S to the secondary transfer area TR, transfers an image to the back surface of the medium S in the secondary transfer area TR, and discharges the medium S via the fixing device 50 to a medium discharge receiver not shown. In addition, the medium transport system 60 is provided with an alignment roll 70 that aligns the leading edge position of the medium S and supplies it to the secondary transfer area TR, as well as an appropriate number of transport rolls 71 on each transport path 63, 64, 66, 69, and an ejection roll 72 that ejects the medium S toward a medium ejection receptacle not shown in the figure is provided near the ejection port 22 of the housing 21, which is the exit of the horizontal transport path 64.

[0032] -Curl correction device- In this embodiment, as shown in FIG. 2 and FIG. 3, a curl correction device 80 is provided on the horizontal conveying path 64 downstream of the fixing device 50 in the medium conveying direction. The curl correction device 80 corrects the curl of the medium S, considering that the medium S that has passed through the fixing zone FR of the fixing device 50 tends to curl during the fixing process by heating and pressurization. Here, the curl that occurs in the medium S includes a down curl in which the leading end side of the medium S in the conveying direction curls downward with respect to the conveying direction, and an upper curl in which the leading end side of the medium S in the conveying direction curls upward with respect to the conveying direction. For this reason, in this example, the curl correction device 80 includes a first curl correction section 81 that mainly corrects the down curl, and a second curl correction section 82 that mainly corrects the upper curl. Note that, for example, a pair of pressure rolls with a small diameter on the down curl side is used as the first curl correction section 81. Also, for example, a pair of pressure rolls with a small diameter on the upper curl side is used as the second curl correction section 82.

[0033] -Cooling device- <The need for cooling equipment> Generally, if the medium S that has passed through the fixing zone FR of the fixing device 50 is discharged while still in a hot state, there is a concern that the toner image will be melted by the heat, and the stacked media S will easily stick to each other. 2 and 3, in this embodiment, a cooling device 90 (corresponding to the medium conveying device 11 in FIG. 1) is provided on the horizontal conveying path 64 downstream in the medium conveying direction of the curl correction device 80. This cooling device 90 cools the medium S that has passed through the fixing zone FR of the fixing device 50, and cools the toner image fixed on the medium S, thereby eliminating the melted state of the toner image due to heat.

[0034] <Basic configuration example of cooling device> 2 to 4, the cooling device 90 is roughly divided into an upper unit 91 disposed above and a lower unit 92 disposed below. The upper unit 91 has a first conveyor belt 93 as a first conveyor means that moves in a circulating manner and has an endless shape, a plurality of (five in this example) tension rolls 94 (specifically 94a to 94e) that stretch the first conveyor belt 93 with a required tension applied, and a heat sink 95 as a cooling means disposed on the inner periphery side of the first conveyor belt 93. The lower unit 92 also has a second conveyor belt 96 as an endless second conveying means that moves in a circular motion, a plurality of (four in this example) tension rolls 97 (specifically 97a to 97d) that stretch the second conveyor belt 96 with the required tension applied, and a pressing roll 98 that is arranged on the inner side of the second conveyor belt 96 and serves as a pressing member that presses the second conveyor belt 96 against the heat sink 95 via the first conveyor belt 93.

[0035] <Components of the upper unit> In this example, an endless belt made of a synthetic resin material such as polyimide is used as the first conveyor belt 93. In this case, the volume resistance of the first conveyor belt 93 may be appropriately selected, but in this example, an appropriate amount of conductive agent is mixed into the synthetic resin material so that the first conveyor belt 93 becomes a conductive member with a volume resistivity of 11 Log Ω·cm or less under a voltage application condition of 500 V / thickness of 100 μm. Among the multiple tension rolls 94, the tension roll 94a arranged close to the downstream side of the heat sink 95 along the belt movement direction is configured as a drive roll for circulating the first conveyor belt 93. The tension roll 94a as the drive roll is rotated by transmitting the driving force of the drive motor 100 via a drive transmission mechanism 101. The tension rolls 94b, 94d, and 94e are configured as driven rolls that hold the running position of the first conveyor belt 93. The tension roll 94c is configured as a tension applying roll that applies a required tension to the first conveyor belt 93 by a biasing spring 102.

[0036] The heat sink 95 is disposed in contact with the inner circumferential surface of the first conveyor belt 93 in the region of the first conveyor belt 93 that is stretched between the tension rolls 94a and 94e. The tension rolls 94a and 94e are disposed above the lower end surface of the heat sink 95, and the first conveyor belt 93 is disposed in contact with the lower end surface of the heat sink 95 due to the tension of the tension rolls. The heat sink 95 is made of a material having a higher thermal conductivity than the first conveyor belt 93, and is made of a metal material such as aluminum. The heat sink 95 is provided with a substrate 951 that contacts the first conveyor belt 93 at its lower end. The lower end surface of the substrate 951 is formed in a curved shape having a large radius of curvature so as to be flat or convex downward. The upstream and downstream ends of the substrate 951 along the belt movement direction have a curved shape with a small radius of curvature.

[0037] The heat sink 95 has a plurality of thin flat heat sinks 952 arranged on the upper end surface of the substrate 951 along the belt width direction intersecting with the belt movement direction, and arranged at required intervals in the belt movement direction so as to be in contact with the substrate 951. A blower 105 is provided as a suction means on the rear side of the heat sink 95 in the belt width direction (corresponding to the rear side in the vertical direction of the drawing). The blower 105 is driven to rotate when the cooling device 90 is in operation, and discharges air sucked from the front side of the housing 21 (corresponding to the front side in the vertical direction of the drawing) to the rear side, thereby bringing the air flow into contact with each heat sink 952 and dissipating heat from each heat sink 952.

[0038] <Components of the lower unit> The second conveyor belt 96 is an endless belt made of a synthetic resin material such as polyimide, similarly to the first conveyor belt 93. In this case, the volume resistance of the second conveyor belt 96 may be appropriately selected, but in this example, the second conveyor belt 96 is configured to be a conductive member with a volume resistivity of 11 Log Ω·cm or less under a voltage application condition of 500 V / thickness of 100 μm by mixing an appropriate amount of conductive agent into the synthetic resin material. Among the multiple tension rolls 97, the tension roll 97a is configured as a drive roll for circulating the second conveyor belt 96. The tension roll 97a as the drive roll is rotated by transmitting the driving force of the drive motor 110 via the drive transmission mechanism 111. The tension roll 97a is disposed so as to face the tension roll 94a of the first conveyor belt 93, and is pressed against the tension roll 94a. The tension rolls 97c and 97d are configured as driven rolls that maintain the running position of the second conveyor belt 96. The tension roll 97b is configured as a tension applying roll that applies a required tension to the second conveyor belt 96 by the biasing spring 112.

[0039] The pressing roll 98 is disposed on the end side of the heat sink 95 where the first conveyor belt 93 starts to come into contact with the heat sink 95, so as to press the second conveyor belt 96 against the heat sink 95 via the first conveyor belt 93. In this example, the pressing roll 98 is disposed at the upstream end of the heat sink 95 in the movement direction of the first conveyor belt 93. The pressing roll 98 is constructed by, for example, covering the outer periphery of a metal core with an elastic layer having a required rubber hardness to a required thickness along the axial direction. The pressing roll 98 is pressed against the heat sink 95 with a required pressing load by elastic members such as compression springs arranged at both ends of the core. The pressing member is not limited to the pressing roll 98, and may be a fixed roll body, a film-like member, or a pad-like member.

[0040] Thus, in this example, the cooling device 90 has a contact area Re between the first conveyor belt 93 and the second conveyor belt 96, the contact area Re corresponding to the area between the tension roll 97a and the pressing roll 98 of the second conveyor belt 96. Of the contact area Re, a contact area Rc corresponding to the area where the heat sink 95 contacts the inner circumferential surface of the first conveyor belt 93 acts as a cooling area that exerts a cooling effect on the medium S. Of the contact area Re, a downstream outlet in the belt movement direction, that is, a nip portion (sandwich portion) between the tension roll 94a as the drive roll of the first conveyor belt 93 and the tension roll 97a as the drive roll of the second conveyor belt 96 functions as an ejection portion 120 of the medium S from the cooling device 90.

[0041] -Additional cooling function- <Example of static elimination unit configuration> In this embodiment, the cooling device 90 includes a charge removing section 130 as a charge removing means for removing charge from the moving medium S in the contact area Re between the first conveyor belt 93 and the second conveyor belt 96. 4 and 5(a), this static elimination unit 130 uses the tension roll 94a of the first conveyor belt 93 and the tension roll 97a of the second conveyor belt 96 as a pair of static elimination rolls 131, 132. In this example, a static elimination power source 135 is connected to the end of the rotation shaft of the static elimination roll 131 that also serves as the tension roll 94a. On the other hand, the static elimination roll 132 that also serves as the tension roll 97a is grounded. In this example, the static elimination power supply 135 has a negative polarity power supply 136 that applies a negative static elimination bias Ve(-) in a variably adjustable manner, a positive polarity power supply 137 that applies a positive polarity static elimination bias Ve(+) in a variably adjustable manner, and a switch 138 that switches between the negative polarity power supply 136, the positive polarity power supply 137, or power off.

[0042] <Example of steering function configuration> In this embodiment, the tension roll 94c of the first conveyor belt 93 functions as a tension-applying roll and also functions as a steering roll 140. The steering roll 140 adjusts the inclination posture so as to suppress the meandering of the first conveyor belt 93 when the first conveyor belt 93 meanders in the width direction. In this example, the tension roll 94c is supported so as to be able to swing about a predetermined swing point 141, as shown in FIG. 4 and FIG. 5(b), and the tilt attitude is adjusted by a tilt adjustment mechanism 142. The swing point 141 may be provided at any position in the axial direction of the tension roll 94c, but in this example, it is provided near one end of the axial direction of the tension roll 94c. The inclination adjustment mechanism 142 moves a bearing 143 of a rotating shaft part of the tension roll 94c on the side farther from the swing point 141 in a direction intersecting the axial direction, swinging the tension roll 94c around the swing point 141, and adjusting the inclination of the tension roll 94c. Here, an example of the inclination adjustment mechanism 142 is one that rotates an eccentric cam 145 by a predetermined amount using a drive motor 144 to vary the swing amount of the tension roll 94c. The tension roll 97b of the second conveyor belt 96 also functions as a steering roll 140 in addition to functioning as a tension applying roll.

[0043] -Cooling device peripheral structure- In this example, the peripheral structure of the cooling device 90 is configured as shown in FIG. <Position sensor> In this embodiment, a position sensor 150 is provided on the horizontal transport path 64 upstream of the cooling device 90 in the transport direction of the medium S. This position sensor 150 detects, for example, the timing when the leading edge of the medium S in the transport direction passes by. <Surface potential sensor> In this embodiment, a surface potential sensor 151 is provided on the horizontal transport path 64 upstream of the cooling device 90 in the transport direction of the medium S. This surface potential sensor 151 detects the charged state (polarity, charge amount) of the medium S that has passed through the secondary transfer area TR by the secondary transfer device 43. <Environmental sensor> In this embodiment, a temperature sensor 152 is provided as an environment sensor for detecting the atmospheric temperature inside the housing 21. <Guide Chute> 4, in the horizontal transport path 64, immediately behind the discharge section 120 of the cooling device 90, a flat guide chute 125 is provided to guide the medium S discharged from the discharge section 120. The guide chute 125 is disposed slightly below a plane extending from the contact area Re of the cooling device 90 in the direction of movement of the medium S, and is disposed with a minute gap (for example, about 1 mm) between the guide chute 125 and the discharge section 120.

[0044] - Cooling device control system - In this example, the control system of the cooling device has a control device 160 configured with a microcomputer including various processors, as shown in Fig. 4. The term "processor" here refers to a processor in a broad sense, and includes general-purpose processors (e.g., CPU: Central Processing Unit, etc.) and dedicated processors (e.g., GPU: Graphics Processing Unit, ASIC: Application Specific Integrated Circuit, FPGA: Field Programmable Gate Array, programmable logic device, etc.). This control device 160 is connected to an operation panel 161 of the media processing system 20 and various detectors such as a position sensor 150, a surface potential sensor 151, and a temperature sensor 152. In addition, the control device 160 transmits appropriate control signals to each controlled object (the drive motors 100, 110, the blower 105, the static elimination power supply 135, the tilt adjustment mechanism 142, etc.). The operation panel 161 is provided with a start switch (not shown) for starting the image forming process on the medium S, and a mode switch (not shown) for specifying an image creation mode such as single-sided printing, double-sided printing, high-resolution printing, etc.

[0045] - Media processing system operation - The basic operation of the media processing system 20 will now be described. <Processing before passing through the cooling device> First, a case where a mode for forming an image on one side of the medium S is performed will be described as an example. When the single-sided color printing mode is specified and a start switch (not shown) is turned on, the media processing system 20 forms an image (each color component image) using each color component toner on the photoconductor 31 using the four image forming units 30 (30a to 30d). Thereafter, each color component image on each photoconductor 31 is primarily transferred to an intermediate transfer body 41 of a transfer device 40 by a primary transfer device 42. Residual matter such as toner remaining on the photoconductor 31 is cleaned by a cleaner 35. Then, each color component image held on the intermediate transfer body 41 is transported to a secondary transfer area TR by the rotation of the intermediate transfer body 41. Meanwhile, in the media transport system 60, the media S is supplied by a feeder 62 from one of the media supply containers 61 (61a, 61b), transported via a vertical transport path 63 and a horizontal transport path 64 to an alignment roll 70, and after being aligned by the alignment roll 70, is transported to the secondary transfer area TR.

[0046] Then, in the secondary transfer region TR, the secondary transfer device 43 collectively transfers the respective color component images on the intermediate transfer body 41 to the medium S. After the secondary transfer, the toner, paper powder, and other residues remaining on the intermediate transfer body 41 are cleaned by the intermediate transfer body cleaner 46. 3, the medium S onto which each color component image has been secondarily transferred passes through a conveyor belt 65 and reaches a fixing device 50. In the fixing device 50, the medium S holding the unfixed color component images is passed through a fixing zone FR between a fixing belt 51 and a pressure roll 52, and each color component image is fixed onto the medium S by a heat and pressure treatment. After the fixing is completed, the medium S is straightened (decurled) by the curl straightening device 80 to make it flat, and is then conveyed to the cooling device 90.

[0047] <Processing using cooling equipment> In this embodiment, the control device 160 controls the cooling device 90 in accordance with the flowchart shown in FIG. First, the control device 160 checks, based on a detection signal from the position sensor 150, whether or not there is a target medium S about to enter the cooling device 90. Now, assuming that there is a target medium S about to enter the cooling device 90, the surface potential sensor 151 detects the surface potential (polarity, charge amount) of the medium S. The control device 160 determines a charge removal bias Ve effective for removing the surface potential of the medium S based on the detection result of the surface potential sensor 151. In this case, when a high resistance medium having a volume resistivity equal to or higher than a predetermined threshold value (for example, a volume resistivity appropriately selected from a range of 12 to 15 Log Ω·cm) is used as the medium S, if the front side of the medium S is charged with a negative charge (-) as shown in S(I) in FIG. 7, the back side of the medium S will be charged with a positive charge (+) due to dielectric polarization, and the medium S will enter the cooling device 90 in a charged state.

[0048] Furthermore, when the leading edge of the medium S passes the position sensor 150, the first conveyor belt 93 and the second conveyor belt 96 of the cooling device 90 are rotated, and the suction operation by the blower 105 on the heat sink 95 is started. Furthermore, a static elimination bias Ve is applied to the static elimination roll 131 of the static elimination unit 130. In this example, as the static elimination power source 135, a static elimination bias Ve(+) from a positive polarity power source 137 is switched and selected. In this state, the cooling device 90 performs a cooling process for the medium S and a static electricity removal process for the medium S.

[0049] In this example, as shown in Fig. 7, when the medium S (II) enters the contact area Re between the first conveyor belt 93 and the second conveyor belt 96, the medium S is cooled in a contact area Rc of the contact area Re, which corresponds to the area where the heat sink 95 contacts the first conveyor belt 93. That is, the front side (upper side in the figure) of the medium S (II) contacts the first conveyor belt 93 and passes through the contact area Rc, which is the cooling area. At this time, the first conveyor belt 93 is directly cooled by the heat sink 95, and the heat sink 95 dissipates heat from the heat sink 952 by the airflow of the blower 105 (see Fig. 4), so that the heat Q of the front side of the medium S is released by the cooling action of the first conveyor belt 93 and the heat dissipation action of the heat sink 95. On the other hand, the second conveyor belt 96 is not provided with a heat sink 95, but since the second conveyor belt 96 contacts the first conveyor belt 93 when the medium S is not passing through, the second conveyor belt 96 is indirectly cooled via the first conveyor belt 93 which is cooled by the heat sink 95. For this reason, the heat Q on the back side of the medium S (II) is also indirectly cooled by the cooling action of the second conveyor belt 96. In this example, by utilizing the information detected by the temperature sensor 152 serving as an environmental sensor, the strength and volume of the airflow from the blower 105 may be adjusted to control the degree of cooling by the heat sink 95.

[0050] The neutralization of the medium S is carried out as follows. That is, when the first conveyor belt 93 is a conductive member and the discharge bias Ve is applied to one discharge roll 131, the first conveyor belt 93 is also applied with the discharge bias Ve. The second conveyor belt 96 is also a conductive member and the other discharge roll 132 is grounded, so the second conveyor belt 96 is also grounded. In this state, when the charged medium S enters the contact area Re between the first conveyor belt 93 and the second conveyor belt 96, the negative charge (-) on the front side of the medium S is discharged in the contact area Re by the charge of the opposite polarity of the first conveyor belt 93 to which the discharge bias Ve (in this example, the positive power source 137 is selected) is applied, and the positive charge (+) on the back side of the medium S escapes to the ground side from the grounded second conveyor belt 96.

[0051] As a result, the medium S is cooled and de-electrified while passing through the contact area Re of the cooling device 90. Therefore, the medium S does not pass through the contact area Re in a charged state, and there is no concern that the medium S will stick to the first conveyor belt 93 or the second conveyor belt 96. At this time, it is known that the scattering time of static electricity is electrical resistance x capacitance. We then investigated the relationship between electrical resistance and relative humidity and found that the electrical resistance exponentially decreases with increasing relative humidity, as shown in Figure 8. In other words, the higher the relative humidity, the greater the decrease in the scattering time of static electricity. Therefore, the absolute humidity (1m 3 Even if the weight of water vapor contained in the air at a certain temperature remains the same, as shown in Figure 8, when the temperature drops, the relative humidity (the ratio of the amount of water vapor contained at that time to the amount of saturated water vapor in a unit volume of air at a certain temperature) increases. For this reason, it can be understood that static electricity dissipates in a short time. Thus, in this embodiment, the cooling device 90 performs a static elimination process while also performing a cooling process on the medium S, making it possible to perform the static elimination process more quickly than when the static elimination process is performed without performing a cooling process.

[0052] -Processing after passing through the cooling device- After passing through the cooling device 90, the medium S (III) with the fixed image retained on one side undergoes cooling and de-electrification processes, and is transported to the discharge outlet 22 of the housing 21 on the horizontal transport path 64, and is discharged by the discharge roll 72 to a medium discharge receiver not shown. 6, it is further possible to check whether there is a next target medium S, and if there is, to continue with the cooling process and the static electricity removal process by the cooling device 90. On the other hand, if there is no next target medium S, it is also possible to turn off the cooling device 90 and turn off the application of the static electricity removal bias Ve of the static electricity removal unit 130.

[0053] The case where a mode for forming images on both sides of the medium S is carried out will be described below. As described above, the medium S having a fixed image held on one side thereof is guided to the branched conveying path 66 midway along the horizontal conveying path 64, and the medium S guided to the branched conveying path 66 is inverted at the inverting section 68, and then returned to the vertical conveying path 63 and the horizontal conveying path 64 via the return conveying path 69, and conveyed again to the secondary transfer area TR. Meanwhile, in the image forming section 30 (30a to 30d), an image is formed with each color component toner to be formed on the back side of the medium S, and after primary transfer to the intermediate transfer body 41 of the transfer device 40, the intermediate transfer body 41 is rotated to move each color component image to the secondary transfer area TR. Thereafter, the respective color component images are secondarily transferred collectively onto the rear surface of the medium S by the secondary transfer device 43 . 3, the medium S onto which each color component image has been secondarily transferred is conveyed via a conveyor belt 65 to a fixing device 50, where the medium S is fixed. Thereafter, the medium S, on both sides of which the images have been fixed, is subjected to a curl straightening process by a curl straightening device 80, and a cooling process and a static electricity removal process by a cooling device 90, and is then discharged from the discharge port 22 of the housing 21 to a medium discharge receiver (not shown).

[0054] -Preferred layout for cooling device exhaust section- <About peeling discharge when ejecting media> In the present embodiment, the medium S passing through the contact area Re between the first conveyor belt 93 and the second conveyor belt 96 is discharged from the discharge section 120 at the exit of the contact area Re. At this time, since the discharge section 120 is configured to also serve as the pair of discharge rolls 131 and 132 constituting the discharge section 130, a discharge bias Ve is applied to the discharge roll 131. In this state, when the medium S is discharged from the discharge section 120, the medium S will be peeled off from the first transport belt 93 or the second transport belt 96, and there is a tendency for peeling discharge to occur when the medium S is peeled off.

[0055] <Discharge behavior of medium from cooling device> Here, the behavior of the medium S when it is discharged from the discharge unit 120 will be considered. As shown in FIG. 9(a), a reference line connecting the axial centers of the paired discharge rolls 131, 132 that constitute the discharge section 120 is designated as Ly, and a vertical line perpendicular to this reference line Ly, passing through the nip portion (clamping portion) of the paired discharge rolls 131, 132, and extending in the discharge direction of the medium S is designated as Lx. 9A, the angle β of the reference line Ly with respect to the vertical line is 0, the vertical line Lx coincides with the horizontal line, and is located on the extension of the contact area Re extending in the substantially horizontal direction. Therefore, the leading end of the medium S discharged from the discharge unit 120 tries to move in the direction of the vertical line Lx. However, when a medium S with low bending rigidity is used, there is a concern that the leading end of the medium S discharged from the discharge unit 120 will sag under its own weight, or will become charged by peeling discharge and stick to the first conveyor belt 93 or the second conveyor belt 96.

[0056] Also, as shown in FIG. 9B, it is assumed that the reference line Ly is disposed at an angle β(-) in the counterclockwise direction with respect to the vertical line. In this case, the vertical line Lx also inclines in the counterclockwise direction with the inclination of the reference line Ly, so that the vertical line Lx inclines obliquely upward with respect to the horizontal line at an angle β(-). Therefore, the leading end of the medium S that has passed through the contact area Re is discharged toward the direction of the vertical line Lx when passing through the discharge section 120. In this state, the leading end of the medium S is slightly bent at the discharge section 120, and the bending rigidity of the medium S increases accordingly. However, when a medium S with low bending rigidity is used, the leading end of the medium S discharged obliquely upward is in an unstable posture, and there is a concern that the leading end of the medium S may stick to the first conveyor belt 93 due to the influence of the peeling discharge described above.

[0057] 9(c), it is assumed that the reference line Ly is inclined clockwise by an angle β(+) with respect to the vertical line. In this case, the vertical line Lx also inclines clockwise with the inclination of the reference line Ly, and therefore the vertical line Lx inclines diagonally downward by an angle β(+) with respect to the horizontal line. Therefore, the leading end of the medium S that has passed through the contact area Re is discharged in the direction of the vertical line Lx when it passes through the discharge section 120. In this state, even if a medium S with low bending rigidity is used, the leading end of the medium S is slightly bent in the discharge section 120, strikes the guide chute 125 in a diagonally downward inclined position, and is transported along the guide chute 125. For this reason, when it is necessary to use a medium S with low bending rigidity, it is preferable to adopt the layout shown in FIG. 9(c) as the configuration of the discharge section 120.

[0058] ◎Embodiment 2 FIG. 10 is an explanatory diagram showing a main part of a cooling device according to the second embodiment. In the figure, the basic configuration of the cooling device 90 is substantially the same as that of the first embodiment, but further includes a discharge attitude variable mechanism 170 as a discharge attitude varying means for varying the discharge angle of the medium S discharged from the discharge unit 120 of the cooling device 90. Note that many of the same components as those in the first embodiment are not shown in Fig. 10, but the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment and detailed description thereof will be omitted here. In this example, the operation panel 161 of the control device 160 is provided with a start switch 162 for starting the image forming process on the medium S, an image creation mode switch 163 for specifying an image creation mode such as single-sided printing, double-sided printing, high-resolution printing, etc., and a media type designation switch 164 for designating a different media type.

[0059] - Media discharge angle - In this embodiment, the discharge angle θ of the medium S discharged from the discharge section 120 of the cooling device 90 corresponds to the inclination angle of the nip portion (clamping portion) of the pair of anti-static rolls 131, 132 that constitute the discharge section 120 with respect to a horizontal line, as shown in FIG. The discharge angle θ of the medium S corresponds to the angle between a vertical line Lx perpendicular to the reference line Ly and a horizontal line, as shown in FIG. 9(a), which corresponds to the angle β between the vertical line and the reference line Ly. Here, when β=0, the layout shown in FIG. 9(a) is obtained, when β=β(-), the layout shown in FIG. 9(b) is obtained, and when β=β(+), the layout shown in FIG. 9(c) is obtained.

[0060] -Relationship between media type and media discharge angle- In this embodiment, the discharge angle θ of the medium S depends on characteristic information (e.g., thickness t) of the medium S. That is, if the medium S has a large thickness t, the bending rigidity is high, and therefore the discharge posture of the medium S discharged from the discharge section 120 is relatively stable. In contrast, if the medium S has a small thickness t, the bending rigidity is low, and therefore the discharge posture of the medium S discharged from the discharge section 120 is likely to be unstable, and the medium S is likely to be affected by peeling discharge and the like. In addition, it has been confirmed that even if the medium type is the same, if the feed speed v of the medium S in the cooling device 90 is different, the appropriate discharge angle θ of the medium S will be different. In this embodiment, as shown in FIG. 11, for each medium type (Sa...Sx), a combination of thickness t (ta1...tx1) as characteristic information and an appropriate discharge angle θ (θa1...θx1, θa2...θx2) of the medium S for each feed speed v (v1, v2...) of the cooling device 90 is confirmed through demonstration experiments, and stored in the RAM of the control device 160 as a characteristic table 165.

[0061] - Variable ejection position mechanism - In this embodiment, as shown in Figures 10 and 12(a) and (b), the discharge attitude variable mechanism 170 has both end holding portions (bearing portions 133) of the charge removal rolls 131, 132 constituting the discharge section 120 held by a pair of plate-shaped holders 171, 172, and has an oscillating shaft 173 provided on the outer surface of each holder 171, 172 at a position corresponding to the nip portion of the paired charge removal rolls 131, 132, and the oscillating shaft 173 is oscillatably supported by a pair of bearings 175. In this example, the pair of charge eliminating rolls 131, 132 are held by a pair of holders 171, 172 so as to maintain a relative positional relationship, and are adapted to swing about a swing shaft 173 as a fulcrum. In this example, the discharge attitude variable mechanism 170 has an eccentric cam 176 arranged on one vertical side edge of one of the holders 171 so that the holder can swing about a swing shaft 173 as a fulcrum, and this eccentric cam 176 is rotated by a drive motor 177. A biasing spring 178 is provided on the other vertical side edge of the holder 171 opposite the eccentric cam 176 to bias the holder 171 towards the eccentric cam 176.

[0062] In this example, as shown in Fig. 12(b), the eccentric cam 176 has a smooth cam surface 176a extending from the small diameter portion rs to the large diameter portion rb via the medium diameter portion rm. In this eccentric cam 176, for example, when the medium diameter portion rm is in contact with the holder 171, the reference line Ly of the paired static elimination rolls 131, 132 is held in the vertical direction. When the small diameter portion rs is in contact with the holder 171, the reference line Ly of the paired static elimination rolls 131, 132 is held at an angle β(-) in the counterclockwise direction (- direction in the figure) from the vertical direction. When the large diameter portion rb is in contact with the holder 171, the reference line Ly of the paired static elimination rolls 131, 132 is held at an angle β(+) in the clockwise direction (+ direction in the figure) from the vertical direction. Incidentally, the eccentric cam 176 can abut against the holder 171 at any point on the cam surface 176a, including the small diameter portion rs, the medium diameter portion rm, and the large diameter portion rb, by adjusting the rotational position of the eccentric cam 176.

[0063] According to this embodiment, when the type of medium to be used is specified using the medium type specification switch 164, for example, the control device 160 refers to the characteristics table 165 shown in FIG. 11 and determines the discharge angle θ of the medium S, taking into account the feed speed v of the cooling device 90. Thereafter, the control device 160 transmits a control signal related to the determined discharge angle information of the medium S to the drive motor 177 of the discharge attitude variable mechanism 170. As a result, the discharge attitude variable mechanism 170 appropriately rotates the eccentric cam 176 based on the control signal to adjust the position of the reference line Ly (or the vertical line Lx) of the paired charge removal rolls 131, 132. As a result, the discharge angle θ of the medium S discharged from the discharge section 120 is set. In this embodiment, the characteristic information (thickness t) of the medium S is that specified by the medium type designation switch 164, but this is not limited to this, and it is also possible to provide a thickness sensor midway through the medium transport system 60 and directly detect the thickness t of the medium S using this thickness sensor.

[0064] Third embodiment FIG. 13 is an explanatory diagram showing a main part of a cooling device according to the third embodiment. In the figure, the basic configuration of the cooling device 90 is substantially the same as that of the first embodiment, but further includes a curl straightening mechanism 180 capable of straightening curls in the medium S. Note that many of the same components as those in the first embodiment are not shown in Figure 13, but the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof will be omitted here. In this example, the curl correction mechanism 180 supports both end holding portions (bearing portions 941) of the tension roll 94e of the upper unit 91 of the cooling device 90 by a lifting mechanism 181 so that the tension roll 94e can be raised and lowered, as shown in FIG. 14(a). The tension roll 94e tensions a portion of the first conveyor belt 93 located in front of the entrance of the contact area Re. The tension roll 94e is supported by a lifting mechanism 181 so as to be movable up and down in the vertical direction.

[0065] Now, as shown in FIG. 14(b), it is assumed that the tension roll 94e is set to a predetermined initial position P0. Here, if the transport trajectory of the medium S entering the control device 160 is L0, the intersection angle α between the belt area between the entrance of the contact area Re of the first transport belt 93 and the tension roll 94e and the transport trajectory L0 of the medium S is set to α0. Next, in a mode in which the leading edge of the medium S has an upper curl portion UC, for example, as shown in FIG. 14(c), the tension roll 94e is raised to a predetermined position P1 above the initial position P0, and the crossing angle α is set to αu (αu>α0). At this time, the entrance shape leading to the contact area Re of the first conveyor belt 93 is retracted above the initial position P0. As a result, the entrance space leading to the contact area Re of the first conveyor belt 93 becomes wider, and the medium S having the upper curl portion UC is stably guided to the contact area Re of the cooling device 90. As a result, the upper curl portion UC of the medium S is straightened while passing through the contact area Re.

[0066] In addition, in a mode in which the leading edge of the medium S has a down curl portion DC, for example, as shown in FIG. 14(d), the tension roll 94e is lowered to a predetermined position P2 below the initial position P0, and the crossing angle α is set to αd (αd<α0). At this time, the entrance shape leading to the contact area Re of the first conveyor belt 93 advances below the initial position P0. As a result, the entrance space leading to the contact area Re of the first conveyor belt 93 becomes narrow, and the medium S having the down curl portion DC is stably guided to the contact area Re of the cooling device 90. As a result, the down curl portion DC of the medium S is straightened while passing through the contact area Re. According to this embodiment, the cooling device 90 further performs curl straightening processing. Therefore, if the cooling device 90 according to this embodiment is used, it is possible to omit the curl straightening device 80 shown in FIG.

[0067] Fourth embodiment FIG. 15 shows a main part of a cooling device according to the fourth embodiment. In the figure, the basic configuration of the cooling device 90 is substantially the same as that of the first embodiment, but further, a non-contact static eliminator 190 serving as a non-contact static eliminator is disposed downstream in the transport direction of the medium S from the static eliminator 130 of the cooling device 90. Note that many of the components similar to those of the first embodiment are not shown in Fig. 15, but the components similar to those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and detailed description thereof will be omitted here.

[0068] In this example, the non-contact static eliminator 190 has a static elimination housing 191 with a channel cross-sectional shape that opens toward the surface side of the medium S transported along the horizontal transport path 64, and a discharge wire 192 is hung along the longitudinal direction within this static elimination housing 191, and a static elimination power source 195 is connected to this discharge wire 192. Here, the static elimination power supply 195 has an AC power supply 196 that outputs an AC voltage component, a DC power supply 197 that outputs a DC voltage component, and a switch 198 that switches between power off and power on. The static elimination power supply 195 applies a static elimination bias Vf consisting of an AC voltage component on which a DC voltage component can be superimposed as necessary, while a chute member 200 consisting of a grounded metal plate is disposed on the back side of the medium S.

[0069] According to the present embodiment, the cooling device 90 performs the cooling process of the medium S and the static electricity removal process of the medium S, similarly to the first embodiment. At this time, even if the neutralization process of the medium S is insufficient, the non-contact neutralizer 190 downstream of the cooling device 90 in the transport direction of the medium S neutralizes the residual charge on the medium S with an AC current, so that the neutralization level on the medium S is further reduced and made more uniform. EXAMPLES

[0070] Example 1 This embodiment is a concrete embodiment of a cooling device 90 according to the second embodiment. In this example, the feed speed v of the medium S of the cooling device 90 is set to 250 mm / s and 500 mm / s, and an experiment was conducted to verify the relationship between the thickness t of the medium S and the appropriate discharge angle θ of the medium S under each speed condition. Specifically, the appropriate discharge angle θ of the medium S here was observed based on whether the peeling operation of the medium S was performed smoothly and the medium S could run stably when the medium S was discharged from the discharge section 120 of the cooling device 90. FIG. 16(a) shows the correlation between the two when the feed rate v is 250 mm / s. FIG. 16(b) shows the correlation between the two when the feed rate v is 500 mm / s. According to Figures 16(a) and (b), it was confirmed that when the thickness t of the medium S becomes thinner, the peeling operation of the medium S does not occur smoothly unless the discharge angle θ is increased to the positive side (corresponding to a direction diagonally downward from the horizontal line).

[0071] (Additional Note) (((1))) a belt-like first conveying means for conveying the medium by contacting one side of the medium; a belt-like second conveying means that faces the first conveying means and contacts the first conveying means, and conveys the medium by sandwiching it in a contact area between the first conveying means and the second conveying means; a cooling means provided on at least one of the first conveying means and the second conveying means, for cooling the medium in the contact area; a static elimination means for applying a static elimination voltage to the first conveying means or the second conveying means to eliminate static electricity from the medium passing through the contact area; A medium transport device comprising: (((2))) In the medium conveying device according to (((1)), 2. A medium transport device according to claim 1, wherein the cooling means cools a rear surface of the contact area of ​​the first transport means or the second transport means. (((3))) In the medium conveying device according to (((2)), The medium transport device according to claim 1, wherein the cooling means is constituted by a heat dissipation means in contact with a rear surface of the contact area. (((4))) In the medium conveying device according to any one of ((1)) to ((3)), A medium conveying device characterized in that the discharge means applies a discharge voltage to a portion of a tension member of the first conveying means or the second conveying means, and applies a discharge voltage to the first conveying means or the second conveying means. (((5))) In the medium conveying device according to (((4)), 2. The medium transport device according to claim 1, wherein the charge removing means uses a tension member for driving as a tension member to which the charge removing voltage is applied. (((6))) In the medium conveying device according to ((4))) or ((5)), The medium conveying device according to claim 1, wherein the static elimination means uses a tension member located at an exit of the contact area in the direction of movement of the medium as the tension member to which the static elimination voltage is applied. (((7))) In the medium transport device according to any one of ((1)) to ((6)), The medium conveying device according to claim 1, wherein the charge eliminating means variably sets the polarity and output value of the charge eliminating voltage. (((8))) In the medium conveying device according to (((7))), The discharge means has a detection means for detecting the charged state of the medium before it enters the contact area, and is characterized in that the polarity and output value of the discharge voltage are variably set depending on the detection result of the detection means. (((9))) In the medium transport device according to ((7))) or ((8)), The discharge means has a discrimination means for discriminating characteristic information of the medium before it enters the contact area, and is characterized in that the polarity and output value of the discharge voltage are variably set depending on the discrimination result of the discrimination means. (((10))) In the medium conveying device according to any one of ((1)) to ((9)), A medium conveying device, characterized in that the first conveying means and the second conveying means are made of conductive materials having a volume resistivity of 11 Log Ω·cm or less under a voltage application condition of 500 V / thickness of 100 μm. (((11))) In the medium transport device according to any one of ((1)) to ((10)), A medium conveying device characterized in that the first conveying means and the second conveying means are arranged such that the shape of the inlet portion leading to the contact area along the movement direction of the medium is deformed into a shape that can correct the curl of the medium. (((12))) In the medium transport device according to any one of ((1)) to ((10)), A medium conveying device characterized in that the first conveying means and the second conveying means have a discharge section consisting of a pair of tension members at the exit of the contact area in the direction of movement of the medium, and this discharge section is provided with a discharge posture variable means for varying the discharge angle of the medium relative to a predetermined reference line. (((13))) In the medium conveying device according to (((12)), The ejection attitude variable means has a discrimination means for discriminating the type or characteristic information of the medium before it enters the contact area, and the ejection angle of the medium is variably set depending on the discrimination result of this discrimination means. (((14))) In the medium transport device according to any one of ((1)) to ((13)), The medium transport device according to claim 1, wherein the cooling means includes a cooling variable means for varying a degree of cooling of the medium passing through the contact area. (((15))) In the medium transport device according to any one of ((1)) to ((14)), 13. A medium transport device, comprising: said first transport means and said second transport means each having a speed varying means for varying a transport speed of said medium passing through said contact area. (((16))) In the medium transport device according to any one of ((1)) to ((15)), A medium transport device characterized by comprising a non-contact type de-electrification means that is provided downstream in the medium transport direction from the exit of the contact area, arranged in a non-contact state with respect to the medium discharged from the contact area, and further de-electrifies the medium by corona discharge obtained by applying a discharge voltage including at least an AC component to a discharge electrode. (((17))) A processing means for performing a process involving charging a moving medium; a medium transport device according to any one of ((1)) to (((16))) that is provided downstream of the processing means in a direction of movement of the medium and that cools the medium while removing static electricity by passing the medium; A media processing system comprising: (((18))) In the media processing system according to (((17))), The media processing system is characterized in that the processing means includes an image creating means for creating an image on an image holding means and transferring the created image to the medium using a transfer electric field, and a fixing means for heating and fixing the image transferred to the medium.

[0072] The medium conveying device of (((1))) has a simple configuration that effectively prevents the medium from sticking during the cooling process when transporting a charged medium, compared to a configuration in which the de-electrification process is performed before or after cooling the medium, and can easily achieve stable medium transportability and improved de-electrification efficiency. According to the medium conveying device of (((2))), the cooling efficiency for the medium passing through the contact area between the first conveying means and the second conveying means can be improved compared to the case where areas other than the contact area between the first conveying means and the second conveying means are cooled. According to the medium transport device of (((3))), the back surface of the contact area can be efficiently cooled with a simple configuration. According to the medium transport device of (((4))), the static elimination means can be easily produced by utilizing a part of the tension member constituting the first transport means or the second transport means. According to the medium conveying device of (((5))), by adding a detection means for detecting when the medium enters the contact area between the first conveying means and the second conveying means, it is possible to operate the static elimination means when the medium enters. This makes it possible to prolong the life of the static elimination means against electrical deterioration over time. According to the medium transport device of (((6))), it is possible to efficiently apply a static elimination voltage to the contact area through which the medium passes, without affecting the entry of the medium into the contact area. According to the medium transport device of (((7))), the application level of the static elimination means can be made variable depending on the charged state of the medium, and the static elimination voltage can be set appropriately. According to the medium conveying device of (((8))), the charged state of the medium can be accurately grasped, the applied level of the static electricity removing means can be made variable depending on the charged state of the medium, and the static electricity removing voltage can be appropriately set. According to the medium conveying device of (((9))), by adding a discrimination means for discriminating characteristic information such as the type and thickness of the medium, it is possible to make the application level of the static elimination means variable depending on the characteristic information of the medium, and to appropriately set the static elimination voltage. According to the medium conveying device of (((10))), the static elimination voltage from the static elimination means can be appropriately applied to the first conveying means and the second conveying means, compared to when the first conveying means and the second conveying means are constructed of insulating materials. According to the medium transport device of (((11))), even if the medium has curl, the curl of the medium can be straightened out while the medium passes through the transfer area. According to the medium transport device of (((12))), the travel of the medium that has passed through the contact area can be stabilized, compared to a case in which the medium transport device is not provided with a discharge position varying means. According to the medium transport device of (((13))), the ejection attitude of the medium passing through the contact area can be appropriately adjusted depending on the type of medium. According to the medium transport device of (((14))), even if the heating state of the medium changes depending on the characteristics of the medium or the processing conditions for the medium, the medium can be appropriately cooled in accordance with the heating state. According to the medium conveying device of (((15))), even if the heating state or charging state of the medium changes depending on the characteristics of the medium or the processing conditions for the medium, the medium can be appropriately cooled or de-electrified by adjusting the cooling time and de-electrification time. In the medium conveying device of (((16))), the static elimination process by the static elimination means employs a method of eliminating static electricity by applying a charge of opposite polarity to the charged polarity of the medium, and even if the static elimination level is insufficient, it is possible to make the static elimination level further reduced and more uniform. According to the media processing system of (((17))), when transporting charged media, compared to a mode in which the de-electrification process is performed before or after cooling the media, a media processing system can be easily constructed that includes a media transport device that has a simple configuration and that effectively prevents the media from sticking during the cooling process, and that can easily achieve stable media transportability and improved de-electrification efficiency. According to the media processing system of (((18))), in a media processing system having an image creating means and a fixing means as processing means, the medium to which an image has been transferred is heated in a charged state, but the medium can be cooled while efficiently discharging electricity, and an image can be properly formed on the medium. [Explanation of symbols]

[0073] 1...first conveying means, 2...second conveying means, 3...cooling means, 4...static charge removing means, 5 (5a)...tensioning member, 6 (6a)...tensioning member, 7...discharge section, 8...discharge position changing means, 10...processing means, 11...medium conveying device, 12...non-contact static charge removing means, CN...contact area, S...medium, θ...medium discharge angle

Claims

1. a belt-like first conveying means for conveying the medium by contacting one side of the medium; a belt-like second conveying means that faces the first conveying means and contacts the first conveying means, and conveys the medium by sandwiching it in a contact area between the first conveying means and the second conveying means; a cooling means provided on at least one of the first conveying means and the second conveying means for cooling the medium in the contact area; a static elimination unit that applies a static elimination voltage to the first transport unit or the second transport unit to eliminate static electricity from the medium passing through the contact area; A medium transport device comprising:

2. 2. The medium transport device according to claim 1, 2. A medium transport device according to claim 1, wherein the cooling means cools a rear surface of the contact area of ​​the first transport means or the second transport means.

3. 3. The medium transport device according to claim 2, The medium transport device according to claim 1, wherein the cooling means is constituted by a heat dissipation means in contact with a rear surface of the contact area.

4. 2. The medium transport device according to claim 1, A medium conveying device characterized in that the discharge means applies a discharge voltage to a portion of a tension member of the first conveying means or the second conveying means, and applies a discharge voltage to the first conveying means or the second conveying means.

5. 5. The medium transport device according to claim 4, 2. The medium transport device according to claim 1, wherein the charge removing means uses a tension member for driving as a tension member to which the charge removing voltage is applied.

6. 5. The medium transport device according to claim 4, The medium conveying device according to claim 1, wherein the static elimination means uses a tension member located at an exit of the contact area in the direction of movement of the medium as the tension member to which the static elimination voltage is applied.

7. 2. The medium transport device according to claim 1, The medium conveying device according to claim 1, wherein the charge eliminating means variably sets the polarity and output value of the charge eliminating voltage.

8. 8. The medium transport device according to claim 7, The discharge means has a detection means for detecting the charged state of the medium before it enters the contact area, and is characterized in that the polarity and output value of the discharge voltage are variably set depending on the detection result of the detection means.

9. 8. The medium transport device according to claim 7, The discharge means has a discrimination means for discriminating characteristic information of the medium before it enters the contact area, and is characterized in that the polarity and output value of the discharge voltage are variably set depending on the discrimination result of the discrimination means.

10. 2. The medium transport device according to claim 1, 13. A medium transport device, comprising: said first transport means and said second transport means made of a conductive member having a volume resistivity of 11 Log Ω·cm or less under a voltage application condition of 500 V / thickness of 100 μm.

11. 2. The medium transport device according to claim 1, A medium conveying device characterized in that the first conveying means and the second conveying means are arranged such that the shape of the inlet portion leading to the contact area along the movement direction of the medium is deformed into a shape that can correct the curl of the medium.

12. 2. The medium transport device according to claim 1, A medium conveying device characterized in that the first conveying means and the second conveying means have a discharge section consisting of a pair of tension members at the exit of the contact area in the direction of movement of the medium, and this discharge section is provided with a discharge posture variable means for varying the discharge angle of the medium relative to a predetermined reference line.

13. 13. The medium transport device according to claim 12, The ejection attitude variable means has a discrimination means for discriminating the type or characteristic information of the medium before it enters the contact area, and the ejection angle of the medium is variably set depending on the discrimination result of this discrimination means.

14. 2. The medium transport device according to claim 1, The medium transport device according to claim 1, wherein the cooling means includes a cooling variable means for varying a degree of cooling of the medium passing through the contact area.

15. 2. The medium transport device according to claim 1, 2. A medium transport device, comprising: a first transport means and a second transport means each having a speed varying means for varying a transport speed of the medium passing through the contact area.

16. 2. The medium transport device according to claim 1, A medium transport device characterized by comprising a non-contact type de-electrification means that is provided downstream in the medium transport direction from the exit of the contact area, arranged in a non-contact state with respect to the medium discharged from the contact area, and further de-electrifies the medium by corona discharge obtained by applying a discharge voltage including at least an AC component to a discharge electrode.

17. A processing means for performing a process involving charging a moving medium; a medium transport device according to any one of claims 1 to 16, which is provided downstream of the processing means in a direction of movement of the medium, and which cools the medium while removing static electricity by passing the medium; A media processing system comprising:

18. 20. The media processing system of claim 17, The media processing system is characterized in that the processing means includes an image creating means for creating an image on an image holding means and transferring the created image to the medium using a transfer electric field, and a fixing means for heating and fixing the image transferred to the medium.

Images