Image forming device

Abstract

To provide an image forming device for preventing wrinkling of a foil sheet member in a rewinding operation.SOLUTION: An image forming device comprises: a supply section having a supply member around which a sheet-like foil sheet member having a foil member and a holding member holding the foil member is wound, and a drive member for rotational driving of the supply member; a wind-up section having a wind-up member for winding up the foil sheet member; a transcript section having a pair of rotating bodies rotating with the foil sheet member sandwiched in between and forming a foil section by transcribing the foil member onto an image on an image-formed recording medium; and a control section that controls the drive member. After the foil member is transcribed onto the recording medium in the transcript section and before the conveyance of the foil sheet member is stopped, the foil sheet member is wound back to the supply section side by starting the rotational drive of the supply member in the direction opposite to the feed direction of transcribing the foil member onto the recording medium.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] A digital foil processing method is widely known, which is capable of expressing a metallic tone with excellent gloss by forming a foil part by foil transfer processing on the surface of a recording medium on which a digital image can be formed. In terms of surface gloss, an image formed by the foil part has a superior gloss to an image formed by so-called metallic toner, and can express a more luxurious feeling.

[0003] For example, Patent Document 1 discloses a configuration in which, in an image forming system equipped with an image forming device and a foil stamping device, the image forming device calculates the distance from the leading edge of the printed paper in the transport direction to the foil image and notifies the foil stamping device. The foil stamping device then calculates the transport distance (rewind amount) of the foil sheet taking into account the distance notified by the image forming device, rewinds the foil sheet by the transport distance, and then performs foil stamping.

[0004] Here, when performing a foil rewinding operation to efficiently use the foil (foil sheet member) in the foil transfer process, wrinkles may occur in the foil member. It is necessary to prevent this from occurring and to realize a configuration that realizes efficient use of the foil member by rewinding and reusing the foil. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to prevent the occurrence of wrinkles in a foil sheet member during a rewinding operation. [Means for solving the problem]

[0006] In order to solve the above-mentioned problem, the invention of claim 1 comprises a supply member on which a sheet-shaped foil sheet member having a foil member and a holding member for holding the foil member is wound, a supply section having a drive member for rotating the supply member, a winding section having a winding member for winding up the foil sheet member, a transfer section having a pair of rotating bodies that rotate while sandwiching the foil sheet member and forms a foil section by transferring the foil member onto an image of an image-formed recording medium, and a control unit that controls the drive member, wherein the control unit controls the drive member to start rotating the supply member in the direction opposite to the feed direction when transferring the foil member to the recording medium after the foil member has been transferred to the recording medium in the transfer section and before the transport of the foil sheet member is stopped, thereby rewinding the foil sheet member toward the supply member side. Effect of the Invention

[0007] According to the present invention, it is possible to prevent the foil sheet member from being wrinkled during the rewinding operation. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing an image forming apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing a foil transfer device as a foil forming unit in the embodiment according to the present invention. [Diagram 3] FIG. 2 is a diagram for explaining a configuration of a foil base paper in an embodiment according to the present invention. [Figure 4] FIG. 1 is a block diagram showing an embodiment of the present invention. [Diagram 5] FIG. 13 is a diagram for explaining loss of a foil member. [Figure 6] 6A and 6B are diagrams for explaining deflection caused by unwinding the foil member. [Figure 7] FIG. 2 is a diagram for explaining a rewinding operation in the first embodiment according to the present invention. [Figure 8] FIG. 4 is a diagram showing a control flow of a rewinding operation in the first embodiment according to the present invention. [Figure 9] FIG. 10 is a diagram for explaining a rewinding operation in the second embodiment according to the present invention. [Figure 10] FIG. 11 is a diagram showing a control flow of a rewinding operation in the second embodiment according to the present invention. [Figure 11] FIG. 4 is a diagram showing a foil forming section having a cooling transport path in an embodiment according to the present invention. [Figure 12] 11A and 11B are diagrams for explaining loss of foil material in a foil forming section having a cooling transport path; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

[0010] In addition, in each drawing for explaining the embodiments of the present invention, components such as parts and components having the same function or shape are given the same symbols as far as possible to distinguish them, and once they have been explained, their explanations will be omitted.

[0011] <Image forming apparatus according to an embodiment of the present invention> 1 shows a color printer as an image forming apparatus according to one embodiment of the present invention. Process cartridges 3Y, 3M, 3C, and 3K are arranged on the upper portion of a device main body 2 of the color printer 1 as image forming units for forming toner images of the respective colors of yellow (Y), magenta (M), cyan (C), and black (K). Each process cartridge 3 is provided with a corresponding photoconductor drum 4Y, 4M, 4C, or 4K.

[0012] 1, charging devices 5Y, 5M, 5C, 5K, developing devices 6Y, 6M, 6C, 6K, and photoconductor cleaning devices 7Y, 7C, 7M, 7K are arranged around each photoconductor drum 4. An optical unit 8A that irradiates laser light onto each photoconductor drum 4Y, 4M is arranged above each process cartridge 3Y, 3M, and an optical unit 8B that irradiates laser light onto each photoconductor drum 4C, 4K is arranged above each process cartridge 3C, 3K. Each optical unit 8A, 8B is a well-known configuration having a laser light source, a polygon mirror, a plurality of lenses, mirrors, etc.

[0013] An intermediate transfer unit 10 having an intermediate transfer belt 9 onto which a toner image formed by each process cartridge 3 is transferred is provided below each process cartridge 3. The intermediate transfer unit 10 has a plurality of rollers supporting the intermediate transfer belt 9, and the intermediate transfer belt 9 is stretched over a drive roller 11, driven rollers 12 and 13, a tension roller 14, and a secondary transfer opposing roller 15. Of the rollers 11, 12, 13, 14, and 15, the drive roller 11 is driven to rotate by a drive motor (not shown), thereby driving the intermediate transfer belt 9 to travel in the clockwise direction indicated by the arrow in FIG. 1.

[0014] Primary transfer rollers 16Y, 16M, 16C, and 16K are provided on the inner periphery of the intermediate transfer belt 9 at positions facing the photosensitive drums 4, for primarily transferring the toner images formed on the photosensitive drums 4 onto the intermediate transfer belt 9. Here, the formation of the toner images of each color on the photosensitive drums 4 and the primary transfer of the toner images onto the intermediate transfer belt 9 will be described.

[0015] 1, each photoconductor drum 4 is rotated counterclockwise, and the surface of each photoconductor drum 4 is irradiated with static elimination light from each static elimination device, thereby initializing the surface potential of each photoconductor drum 4. The initialized surface potential of each photoconductor drum 4 is uniformly charged to a predetermined polarity (negative polarity in this embodiment) by each charging device 5. The charged surface of each photoconductor drum 4 is irradiated with laser beams emitted from optical units 8A and 8B, respectively, and an electrostatic latent image corresponding to each color image is formed on the surface of each photoconductor drum 4.

[0016] The electrostatic latent images formed on the photoconductor drums 4 are visualized as toner images by the respective developing devices 6. Meanwhile, a transfer voltage of a polarity opposite to that of the toner images formed on the respective photoconductor drums 4 (positive polarity in this embodiment) is applied to each primary transfer roller 16. As a result, a transfer electric field is formed between each photoconductor drum 4 and each corresponding primary transfer roller 16, and each color toner image on each photoconductor drum 4 is electrostatically transferred onto the intermediate transfer belt 9. At this time, each color toner image is superimposed and transferred onto the intermediate transfer belt 9, and a full-color toner image is formed on the intermediate transfer belt 9. After each photoconductor drum 4 has had its color toner image transferred onto the intermediate transfer belt 9, the transfer residual toner adhering to its surface is removed by each photoconductor cleaning device 7, and the photoconductor drum 4 is prepared for new image formation.

[0017] A secondary transfer roller 17, which performs a secondary transfer of a toner image, which has been primarily transferred onto the intermediate transfer belt 9, onto a recording medium, is provided downstream of the primary transfer roller 16K in the running direction of the intermediate transfer belt 9, facing the secondary transfer opposing roller 15. The secondary transfer roller 17 is configured to be freely contactable with and separable from the intermediate transfer belt 9, which is stretched over the secondary transfer opposing roller 15, and selectively occupies a contact position where it contacts the intermediate transfer belt 9 and a separation position where it is separated from the intermediate transfer belt 9. The secondary transfer roller 17 and the secondary transfer opposing roller 15 come into contact with each other via the intermediate transfer belt 9 when the secondary transfer roller 17 occupies the contact position to form a secondary transfer nip N, and form a secondary transfer area when the secondary transfer roller 17 occupies the separation position. A predetermined transfer voltage is applied to the secondary transfer roller 17, and the toner image formed on the intermediate transfer belt 9 in the secondary transfer nip N is secondarily transferred onto the recording medium. In addition, a belt cleaning device 18 is provided downstream of the secondary transfer opposing roller 15 in the running direction of the intermediate transfer belt 9 to remove residual toner remaining on the intermediate transfer belt 9 after image transfer. The intermediate transfer unit 10, the primary transfer rollers 16, the secondary transfer roller 17, and the belt cleaning device 18 constitute a transfer section 19.

[0018] To the left of the secondary transfer roller 17, a fixing device 20 is disposed as a fixing section having a heating belt 20a as a heating means and a pressure roller 20b as a pressure means for fixing the toner image secondarily transferred onto the recording medium. The heating belt 20a has a well-known configuration having a heating roller 20a1 having a heating means such as a heater inside, a driving roller 20a2 rotated and driven by a motor (not shown), and a belt member 20a3 stretched between the rollers 20a1 and 20a2. The pressure roller 20b is biased by a biasing means (not shown) and its peripheral surface is pressed against the peripheral surface of the heating roller 20a1 via the belt member 20a3 with a predetermined pressure contact force.

[0019] Between the secondary transfer roller 17 and the fixing device 20, a transport conveyor 21 is provided to transport the recording medium that has passed through the secondary transfer nip N to the fixing device 20. The transport conveyor 21 is a well-known conveyor having a drive roller, a driven roller, an endless belt stretched between the rollers, and the like. In addition, a sheet transport member 39 configured by pressing a roller against the conveyor is disposed downstream of the fixing device 20 in the recording medium transport direction. The sheet transport member 39 transports the recording medium that has been fixed in the fixing device 20 further downstream.

[0020] A paper feed section 22 is disposed at the bottom of the device main body 2. The paper feed section 22 has paper feed cassettes 23, 24, paper feed rollers 25, 26, a plurality of conveying roller pairs 27, and a registration roller pair 28. Paper S (an example of a recording medium, also called a transfer sheet) that is a recording medium accommodated in the paper feed cassettes 23, 24 is separated and fed by the paper feed rollers 25, 26, fed via the conveying roller pair 27 toward the registration roller pair 28, and then temporarily stopped by the registration roller pair 28. The registration roller pair 28 feeds the temporarily stopped paper S toward the secondary transfer nip N at a predetermined timing when the toner image formed on the intermediate transfer belt 9 matches a predetermined position of the paper S.

[0021] At the top of the apparatus main body 2, toner bottles 29Y, 29M, 29C, and 29K, each containing a corresponding color toner to be supplied to each developing device 6, are arranged.

[0022] When a full-color toner image is formed on the intermediate transfer belt 9, in the paper feed section 22, one sheet of paper S in the paper feed cassette 23 or 24 is separated and fed by the operation of the paper feed roller 25 or 26. The fed paper S is temporarily stopped by the registration roller pair 28, and then sent to the secondary transfer nip N at a predetermined timing by the operation of the registration roller pair 28.

[0023] At the secondary transfer nip N, the paper S onto which the full-color toner image formed on the intermediate transfer belt 9 has been transferred is sent to the fixing device 20, where the transferred image is fixed. The paper S onto which the image has been fixed is transported to a paper discharge path 32, and then discharged onto a paper discharge tray 31 provided on the side of the device main body 2 by a pair of discharge rollers 30 arranged downstream of the fixing device 20 in the sheet conveying direction. As with each photoconductor drum 4, residual toner remaining on the intermediate transfer belt 9 is cleaned by a belt cleaning device 18. A predetermined amount of each color toner contained in each toner bottle 29 is replenished to the corresponding developing device 6 via a toner conveying path (not shown) as necessary.

[0024] The color printer 1 has a reversing conveying section 37 consisting of a switching claw 33, a first re-conveying path 34, a switchback passage 35, a second re-conveying path 36, a circular conveying path 48, etc., and is configured to be able to perform a double-sided image forming operation in which images are formed on both sides of the paper S, and a re-conveying operation in which the image-forming side of the paper S, on which an image has been formed once, is conveyed again to the secondary transfer area.

[0025] More specifically, during a one-sided image forming operation in which an image is formed on only one side of the sheet S, the switching claw 33 sets the conveyance destination of the sheet S to the sheet discharge path 32. As a result, the sheet S with an image formed on only one side is sent to the pair of discharge rollers 30 via the sheet discharge path 32 and discharged onto the sheet discharge tray 31.

[0026] During double-sided image formation and re-conveyance operations, the switching claw 33 switches the subsequent transport destination of the paper S received from the fixing device 20 to the paper discharge path 32 or the first re-conveyance path 34. During double-sided image formation, when the paper S with toner images fixed on both sides is received from the fixing device 20, the switching claw 33 sets the transport destination of the paper S to the paper discharge path 32. As a result, the paper S with images formed on both sides is discharged onto the paper discharge tray 31 by the discharge roller pair 30.

[0027] On the other hand, during double-sided image formation, when the sheet S with an image fixed only on one side is received from the fixing device 20, the switching claw 33 sets the destination of the sheet S to the first re-conveying path 34. The switchback passage 35 and the circular conveying path 48 are connected to the first re-conveying path 34, and the sheet S sent to the first re-conveying path 34 is guided by the switching claw 49 to enter the switchback passage 35. Then, the pair of rollers 50 provided in the switchback passage 35 is reversed to reverse the front and back and front and rear of the sheet S, and the reversed sheet S is guided by the switching claw 38 and re-sent to the secondary transfer nip N via the second re-conveying path 36. The sheet S with the toner image transferred to the other side at the secondary transfer nip N is fixed to the other side via the fixing device 20, and then discharged onto the sheet discharge tray 31 via the switching claw 33, the sheet discharge path 32, and the pair of discharge rollers 30.

[0028] The circular conveying path 48 is used when the paper S that has passed through the fixing device 20 is sent again to the secondary transfer nip N (secondary transfer area) without being inverted front to back or front to back. The paper S sent to the first re-conveying path 34 is guided by the switching claw 49 to enter the circular conveying path 48, and is then re-sent to the secondary transfer nip N in the same position as before via the second re-conveying path 36.

[0029] <Foil transfer device according to an embodiment of the present invention> FIG. 2 is a diagram showing a foil transfer device as a foil part forming section according to one embodiment of the present invention. FIG. 2(a) is a diagram showing an outline of the foil transfer device, and FIG. 2(b) is a diagram showing the driving configuration of the foil transfer device. The foil transfer device will be described in detail below using these figures. The rotation direction of each roll is as shown by the solid arrow in the figure. In FIG. 2(b), the foil supply roll 41, the heating roller 42 and the take-up roll 44 are shown by dashed lines for convenience. In addition, the numerical values ​​given below are merely examples, and the present invention is not limited to these.

[0030] First, as shown in FIG. 2(a), the foil transfer device 40 has a supply section 410, a foil transfer section 420, a winding section 440, a guide roller 53, a foil base paper 60, a separation section 45, a paper trailing edge detection sensor 56, and a foil usage detection sensor 57.

[0031] Here, the supply unit 410 (an example of a supply unit) has a foil supply roll 41, a torque limiter 41a (an example of a torque control means), and a supply drive 41b (an example of a drive member) as shown in FIG. 2(b). The foil supply roll 41 (an example of a supply member, also referred to as a supply roll in this specification) is configured by winding a foil base paper 60 having a foil member 60f having an aluminum deposition layer on one side and a base paper 60p (an example of a holding member) which is a holding member for holding the foil member 60f (an example of a foil member) on the other side in a manner in which one side faces outward. The foil base paper 60 (an example of a foil sheet member) is in the form of a long sheet. The torque limiter 41a (an example of a torque control means) is a limiting means for limiting the torque of the rotation shaft of the foil supply roll 41, and the supply drive 41b is a drive member for rotating and driving the foil supply roll 41. Examples of this drive member include a drive motor. The supply drive 41b, which will be described in detail later, starts reverse driving toward the foil supply roll 41 before stopping the transport of the foil base paper 60 when the transfer of the foil member 60 onto the recording medium, paper, and rewinds it onto the foil supply roll 41. When the foil base paper 60 is wound up by the winding roll 44, the foil supply roll 41 rotates following the rotation of the winding roll 44. At this time, the foil supply roll 41 is provided with a stopper (not shown) to prevent it from rotating too much, and the foil base paper 60 is supplied between the rollers 42, 43 while maintaining a predetermined tension.

[0032] Next, a description will be given of the foil transfer unit 420. As shown in Fig. 2(b), the foil transfer unit 420 (an example of a transfer unit, also referred to as a transfer unit) has a heating roller 42, a pressure roller 43 (an example of a pair of rotating bodies), and a contact / separation means 43a (an example of a contact / separation means).

[0033] The heating roller 42 has a heat source 42a, such as a halogen heater, inside, and is disposed to correspond to the other side of the foil base paper 60. The heating roller 42 may have an external heat source or may be an IH type. The heating roller 42 is driven to rotate by a heating drive 42b, such as a drive motor. As a result, when foil transfer to the paper S is performed, the heating roller 42 rotates clockwise as shown in the figure. The heating roller 42 has a metal core on which a silicone rubber layer having a thickness of 2 mm is formed. The outer diameter φ of the heating roller 42 is 40 mm.

[0034] The pressure roller 43 is disposed corresponding to one side of the foil base paper 60, and its peripheral surface is pressed against the peripheral surface of the heating roller 42 with a predetermined pressure by a biasing means (not shown). The pressure roller 43 has a metal core and a fluororesin rubber layer with a thickness of 0.5 to 1 mm formed thereon. The heating roller 42 has an outer diameter φ of 40 mm. The reason for using fluororubber here is to improve releasability. The pressure roller 43 is provided with a contact / separation means 43a, and the pressure roller 43 moves between a contact position shown by a solid line in FIG. 2(b) and a separation position shown by a two-dot chain line by the operation of the contact / separation means 43a. At the contact position, the pressure roller 43 presses (nips) the peripheral surface of the heating roller 42 with a predetermined pressure, and when it occupies the separation position, the peripheral surface of the pressure roller 43 separates from the peripheral surface of the heating roller 42, creating a gap between the rollers 42 and 43 through which the paper S can pass.

[0035] When performing foil transfer onto paper S, foil transfer unit 420 sets the heating temperature of heating roller 42 to 120-160°C to obtain the required amount of heat, and transfers foil member 60f from foil base paper 60 onto paper S. Note that a heating temperature of 150°C is preferable for heating roller 42. Also, foil transfer unit 420 applies pressure at a pressure set to 3000 N to enable foil transfer onto various types of paper. Note that this pressure is higher than the surface pressure in fixing device 20.

[0036] Next, the winding section 440 will be described. As shown in FIG. 2(b), the winding section 440 (one example of a winding section) has a winding roll 44 (one example of a winding member), and a torque limiter 44a (one example of a torque control means). The winding roll 44 has a core (rotating shaft) not shown, and the foil base paper 60 is wound up at a predetermined speed by rotating this core. The winding roll 44 is rotated by the heating drive 42b when winding up the foil base paper 60. The rotating shaft of the winding roll 44 is connected to the heating drive 42b via a drive gear 44b. When the foil supply roll 41 rewinds the foil base paper 60, the winding roll 44 rotates following the rotation of the foil supply roll 41.

[0037] The guide roller 53 is a guide member for guiding the foil base paper 60 to the foil transfer section 420. The separation section 45 is disposed at a position that provides a separation angle for the foil base paper 60 to separate from the paper S, in order to separate the paper S, which is fed to the foil transfer device 40 and has the foil member 60f transferred to one side thereof, from the foil base paper 60 on which the foil member 60f is used. The separation section 45 has a large curvature, which applies pressure to the paper S, allowing the two to be separated. The paper trailing edge detection sensor 56 is a sensor for detecting that the trailing edge of the paper S has passed through the separation section 45, and is provided near the separation section 45. In the present invention, the rewinding drive is started when the paper trailing edge detection sensor 56 detects the trailing edge of the paper.

[0038] Moreover, the foil usage detection sensor 57 (an example of a detection means) is a sensor that detects unused areas of the foil base paper 60. In reality, the foil usage detection sensor 57 detects the portion (foil-used portion 60h) where the foil member 60f is used to transfer to the paper S. In this embodiment, a transmission type sensor is used as the foil usage detection sensor. The portion of the foil base paper 60 where the foil member has been used to transfer to the paper (i.e., the base paper) is transparent. Therefore, the foil usage detection sensor 57 can determine the amount of rewinding of the foil base paper by detecting the portion of the foil base paper where the foil has been used to transfer to the paper. The rewinding operation will be described in detail later.

[0039] In this embodiment, the foil transfer device 40 described above is used in place of the sheet conveying member 39 in the color printer 1. As with the configuration disclosed in JP 2020-196551 A, the foil transfer device 40 may not be provided in the device body 2 of the color printer 1, but may be connected to the color printer 1 as a separate device. In this case, there is no need to provide the contact / separation means 43a, and the device configuration can be simplified.

[0040] Next, an image forming operation for forming a foil image portion on the paper S using the color printer 1 having the above-mentioned configuration will be described.

[0041] First, a description will be given of a foil portion forming process for forming a foil portion on the paper S. When forming a foil portion on the paper S, for example, similar to the technology disclosed in Japanese Patent No. 5782893, a first process of forming a base image portion for transferring a foil member 60f onto the paper S and a second process of transferring the foil member 60f onto the formed base image portion are performed.

[0042] First, the first step will be described. First, one sheet of paper S is fed from the paper feed tray 23 or the paper feed tray 24, and the fed sheet S is temporarily stopped by the pair of registration rollers .

[0043] At the same time as the paper S is fed from the paper feed unit 22, the process cartridge 3K is operated to rotate the photosensitive drum 4K. A laser beam corresponding to the foil portion to be formed is irradiated from the optical unit 8B onto the peripheral surface of the photosensitive drum 4K to form an electrostatic latent image. The formed electrostatic latent image is developed by the developing device 6K, and a toner image corresponding to the foil portion to be formed is formed on the peripheral surface of the photosensitive drum 4K. Then, the primary transfer roller 16K is operated to perform primary transfer of the toner image formed on the peripheral surface of the photosensitive drum 4K onto the intermediate transfer belt 9. Note that, when the process cartridge 3K is operated, the other process cartridges 3Y, 3M, and 3C are each stopped. After that, the registration roller pair 28 is operated in time with the toner image on the intermediate transfer belt 9, and the paper S that was temporarily stopped is fed toward the secondary transfer nip N. At the secondary transfer nip N, a predetermined transfer voltage is applied to the secondary transfer roller 17 in accordance with the traveling intermediate transfer belt 9 and the fed paper S, and the toner image on the intermediate transfer belt 9 is transferred onto the paper S to form a base image portion 46 (an example of an image) on one side of the paper S. The transfer sheet on which the base image portion 46 has been formed is transported by the transport conveyor 21 to the fixing device 20. When the paper S sent to the fixing device 20 passes through the pressure contact portion between the heating belt 20a and the pressure roller 20b, the transferred base image portion 46 is fixed by heat and pressure.

[0044] Next, the second step will be described. The second step will be described briefly here, as it will be described in detail later. The paper S on which the base image portion 46 has been fixed is sent to the foil transfer device 40 provided instead of the sheet transport member 39 on the downstream side of the paper transport direction (sheet transport direction). In the foil transfer device 40, the pressure roller 43 is in the separated position due to the operation of the contact / separation means 43a. Then, when the paper S is detected by a sensor (not shown), the contact / separation means 43a is operated to displace the pressure roller 43 from the separated position to the pressed position at the timing when the base image portion 46 reaches the opposing position between the heating roller 42 and the pressure roller 43. At the same time, the rotation shaft of the winding roll 44 rotates so that the foil base paper 60 is sent out from the foil supply roll 41 at the same transport speed as the transport speed of the paper S. Due to the displacement of the pressure roller 43 and the rotational drive of the core of the winding roll 44, the foil member 60f is pressed against the base image area 46 on the paper S, and the pressed foil member 60f is transferred by heat and pressure onto the base image area 46. Through this series of operations, the foil member 60f adheres to the base image area 46 on one side of the paper S to form a transferred foil image 60g, completing the foil portion forming process.

[0045] The sheet S having the foil image formed on one side is discharged and stacked on a discharge tray 31 by the operation of a pair of discharge rollers 30 if no further image formation is to be performed. On the other hand, when a further image is to be formed, an image transfer step is subsequently carried out.

[0046] <About the composition of foil base paper> Here, Fig. 3 is a diagram showing the configuration of the foil base paper in an embodiment according to the present invention. Fig. 3(a) shows each layer that makes up the foil base paper, Fig. 3(b) shows the state in which the foil member is transferred to the paper on which an image is formed, and Fig. 3(c) is a diagram showing the foil base paper as viewed from above Fig. 3(a). The details of the configuration of the foil base paper in an embodiment according to the present invention will be explained using these figures. Note that the numerical values ​​given below are merely examples, and the present invention is not limited to these.

[0047] First, as shown in FIG. 3(a), the foil base paper 60 is formed by arranging layers in the order of polyester film layer (also called base film layer) 60a, which is a supporting member, release layer 60b, color layer 60c, special vapor deposition layer 60d, and adhesive layer 60e from the top of the figure. In the foil base paper 60, the total thickness of the release layer 60b, color layer 60c, special vapor deposition layer 60d, and adhesive layer 60e is about 4 to 6 μm. The thicknesses of each layer are as follows: polyester film layer 60a is 12 μm, release layer 60b is 0.02 μm, color layer 60c is 1 to 2 μm, special vapor deposition layer (aluminum vapor deposition layer) 60d is 40 nm, and adhesive layer 60e is 2 to 6 μm. The reason for these values ​​is to suppress the thickness as much as possible when wound up.

[0048] In this configuration, when the foil member 60f is transferred to the paper S on which an image has been formed, the polyester film layer 60a is separated from the other layers (color layer 60c, special vapor deposition layer 60d, and adhesive layer 60e) by the release layer 60b, as shown in FIG. 3(b). Then, the color layer 60c, the special vapor deposition layer 60d, and the adhesive layer 60e are transferred (foil transferred) to the base image portion 46 of the paper S on which an image has been formed. During this transfer, heat and pressure are applied, and the toner forming the base image portion 46 melts, and these layers are bonded together. The three layers transferred to the base image portion 46 correspond to the foil member 60, and the remaining portion corresponds to the transparent base paper 60p (see FIG. 3(a)).

[0049] The color layer 60c is a layer for expressing the color when a foil member is transferred onto the image. For example, if the color layer 60c is yellow, the image will look like it has gold foil applied.

[0050] 3(c) shows the foil base paper 60 as viewed from above in FIG. 3(a) (from the polyester film layer 60a toward the adhesive layer 60e), and the width W of the foil base paper 60 in the direction perpendicular to the conveying direction in this embodiment is 320 mm. The overall winding dimension of the foil base paper 60 in this embodiment (the length in the direction parallel to the conveying direction) is 120 to 240 m.

[0051] <Block diagram showing an embodiment according to the present invention> 4 is a block diagram showing an embodiment of the present invention, an example of an image forming apparatus 1 will be described with reference to FIG.

[0052] The image forming apparatus 1 is connected to a computer (PC) 90 as an external control device so as to be able to communicate with it. The computer 90 has a printer driver, and converts image data into recording data (print data) that can be printed by the image forming apparatus 1 and transmits the data to the image forming apparatus 1. The print data includes command data for operating the imaging units of the image forming apparatus 1 and pixel data relating to the image. In addition, a foil transfer instruction application for executing foil transfer to the foil transfer device 40 is pre-installed in the computer 90.

[0053] The image forming apparatus 1 also includes a paper feed section 22, an imaging unit 200, a foil transfer device 40, a detection group 120, a control section 80 (an example of a control section), etc. The imaging unit 200 refers to a group of units related to image formation, such as the charging device 5, the developing device 6, the transfer section 19, and the fixing device 20. The detection group 120 refers to a group of detection means (sensors) in the image forming apparatus 1, such as a sensor that detects a sheet in the transport path, or, in the case of the foil transfer device 40, the paper trailing edge detection sensor 56 and the foil use detection sensor 57.

[0054] The control unit 80 functions as a control means in the present invention, and includes a unit control 81, a memory 82, a CPU 83, and an interface (I / F) 84. The unit control 81 (an example of a control unit) is a control circuit that controls each unit in the image forming apparatus 1. The memory 82 stores and holds a program for causing the CPU 83 to perform the control in the present invention. The interface (I / F) 84 also functions as a communication unit that communicates with an external device, such as sending and receiving print data from a computer (PC) 90 via a network.

[0055] This control unit 80 controls the printing operation by controlling the paper feed unit 22, the imaging unit 200, the foil transfer device 40, etc., based on the print data received from the computer (PC) 90 and the detection signals of the detection group 120. The program stored in the memory 82 is a program for causing the CPU 83 to perform processing for controlling the printing operation.

[0056] <About foil material loss> Fig. 5 is a diagram for explaining loss of foil material. Note that the image shown in Fig. 5 is one example. Using Fig. 5, the occurrence of loss of foil material when the foil material is transferred to a sheet on which an image is formed will be explained. Note that the "loss of foil material" here refers to the occurrence of foil material that is not transferred to an image portion and remains unused and is wound up.

[0057] Here, it is assumed that the foil member is transferred to the image shown in Fig. 5. This image is formed in a predetermined area on the leading end side (the end side downstream in the transport direction), and is not formed in a predetermined area on the trailing end side (the end side upstream in the transport direction). Therefore, the predetermined area on the leading end side is a foil transferred area where the foil member is transferred, and the predetermined area on the trailing end side is a foil non-transferred area where the foil member is not transferred.

[0058] When transferring the foil member to such an image, the foil member is transferred only to a specified area on the leading edge side where the image is located. However, when transferring the foil member, it is necessary to feed the foil member to the foil transfer section by the size of the paper. Therefore, the foil base paper is wound up not only in the part where the foil member is transferred, but also in the part where the foil member is not transferred. And this part where the foil is not transferred corresponds to the foil non-transferred area.

[0059] This area where the foil has not been transferred is an unused area of ​​the foil material, and if it is wound up as is, it will result in a loss of the foil material. Since foil base paper is more expensive than general paper, it is necessary to minimize the unused area and prevent wasteful consumption. Therefore, in the present invention, the pressure bonding operation is released after the foil transfer in the foil transfer section, and the length of the unused area is rewound, thereby achieving efficient use of the foil material. However, in this case, the following problem may occur.

[0060] <About deflection caused by unwinding> FIG. 6 is a diagram for explaining the deflection caused by the rewinding of the foil base paper (foil member). The deflection shown in FIG. 6 is merely one example. Note that FIG. 6 shows a case where a foil image 60g is formed on the base image section 46 of the paper S on which an image has been formed by transferring the foil member 60f in the foil transfer section 420, and the foil image 60g is wound up by the foil supply roll (supply roll) 41 to perform the rewinding operation. Also, 60h indicates the part of the foil base paper 60 after the foil member 60f has been transferred. The foil member 60f comes out of this part. Note that the rotation direction of each roll is as shown by the solid arrow in the figure.

[0061] As shown in FIG. 6, the foil base paper 60 does not assume a predetermined state (part indicated by a broken line) by the rewinding operation, but sags and becomes a bent foil base paper 60t. The cause of this sagging is a backlash of the driving gear when the winding operation of the foil base paper 60 by the winding roll 44 is stopped, or the slackness of the foil base paper 60 due to the depressurization operation of the pressure roller 43, etc. In such a state, if the foil member 60f is transferred to the paper S on which an image has been formed, wrinkles may occur, which may deteriorate the quality of the image. Therefore, the present invention has the following configuration in order to suppress wrinkles that occur during the foil transfer operation by applying an appropriate tension to the foil base paper, and to obtain a good foil image even if the foil base paper (foil member) is rewound and reused.

[0062] <Regarding the First Embodiment> FIG. 7 is a diagram for explaining the rewinding operation in an embodiment (first embodiment) of the present invention. Using this diagram, we will explain how the present invention addresses the above-mentioned problems. In the first embodiment, it is assumed that the preceding and succeeding sheets of paper have the same image formed thereon and are sent to the foil transfer section. The rotation direction of each roll is as shown by the solid arrow in the diagram. The dashed line in the diagram indicates the movement direction of the foil base paper.

[0063] [Operation in the first embodiment] First, as shown in Fig. 7(a), it is assumed that the foil member 60f is foil-transferred from the foil base paper 60 to the base image section 46 of the preceding paper S1, which is the paper on which an image is formed first. Then, the preceding paper S1 is transported toward the foil transfer section (transfer section) 420. At this time, the unit control 81 (control section 80) drives the heating drive 42b, so that the foil base paper 60 is supplied from the foil supply roll (supply roll) 41 as shown by the dashed arrow, and is taken up by the take-up roll 44. In addition, the heating roller 42 and the pressure roller 43 also rotate in a direction that is aligned with the transport direction of the preceding paper S1.

[0064] Next, as shown in Fig. 7(b), the preceding paper S1 passes through the foil transfer section (transfer section) 420, at which time the foil member 60f is transferred from the foil base paper 60 to the base image section 46. The transferred portion of the foil base paper 60 is transparent, and the foil member 60f is missing. The portion where the foil member 60f is missing corresponds to the foil-used portion 60h (an example of a region where the foil member is used). This portion is transparent.

[0065] Thereafter, as shown in FIG. 7(c), the rear end of the preceding sheet S1 passes through the sheet rear end detection sensor 56. The preceding sheet S1 is peeled off from the foil base paper 60 by the separation unit 45. A transferred foil image 60g (an example of a foil portion) is formed on the base image unit 46. The unit control 81 controls the supply drive 41b to rotate the foil supply roll 41 in the opposite direction to the winding operation, and starts the rewinding drive (reverse drive). At this time, since the foil base paper 60 is sandwiched by the nip between the two rollers of the foil transfer unit 420, the reverse drive becomes idle due to the torque limit. Furthermore, the unit control 81 stops the winding roll 44 and stops sending the foil base paper 60 to the winding roll 44 side.

[0066] Then, the unit control 81 controls the contact / separation means 43a to separate the pressure roller 43 from the heating roller 42 to release the pressure. After that, the unit control 81 controls the supply drive 41b to rotate the foil supply roll 41 in the direction of rewinding towards the supply section 410. Then, the foil supply roll 41 and the take-up roll 44 perform the rewinding operation of the foil base paper 60.

[0067] As the rewinding operation proceeds, as shown in FIG. 7(d), the foil-used portion 60h reaches the foil-used detection sensor 57, and the foil-used detection sensor 57 detects the foil-used portion 60h. At this time, the unit control 81 stops the rewinding operation of the foil base paper 60 by the foil supply roll 41. Then, the following sheet S2 is transported toward the foil transfer section (transfer section) 420. At the same time, in order to transfer the foil onto the base image section 46 of the following sheet S2, the unit control 81 drives the heating drive 42b, and the winding operation in which the foil base paper 60 is wound up by the winding roll 44 is performed again. Then, FIG. 7(a) to (d) are repeated.

[0068] As described above, the present invention is configured to drive the supply side and continue to apply tension before the foil base paper winding operation is stopped, thereby suppressing wrinkles that occur when the operation is stopped. In addition, the present invention uses a foil usage detection sensor to perform the foil base paper rewinding operation and determine the rewinding amount, so there is no need to input image information such as the printing position of the printed matter to the foil transfer device, and the use efficiency of the foil material can be improved with a simple device configuration.

[0069] [Applied tension] Here, as described above, the supply section 410 and the winding section 440 in the foil transfer device 40 according to the present invention are provided with torque limiters 41a and 44a, respectively. Here, when the limit torque of the rotating shaft of the foil supply roll 41 of the supply section 410 is Tk and the limit torque of the rotating shaft of the winding roll 44 of the winding section 440 is Tm, the relationship between the two is Tk>Tm. In this way, it is possible to apply tension to the foil base paper when rewinding the foil base paper on the supply side. Also, if Tm is made larger than Tk, it will be as if a brake has been applied on the winding side, and the foil base paper will not be able to be rewinded on the supply side. In order to prevent this from happening, Tk>Tm is set as described above. In this embodiment, Tk is set to 0.25 (N·m) and Tm is set to 0.15 (N·m).

[0070] The tension T(N) applied during rewinding can be expressed as T(N)=(brake torque / radius). Here, the brake torque acting as a brake is expressed as the difference between the two (Tk-Tm). The radius refers to the radius of the winding diameter of the foil base paper. In this embodiment, the brake torque is 0.1 (N·m). The winding diameter of the foil base paper is an outer diameter of φ20-60 mm, although it varies depending on the usage state of the foil member. In consideration of this, the tension T(N) in this embodiment is 3.3-10 (N). The reason for setting the tension at such a value is that if the tension is too large, the foil base paper may stretch or tear, and the above value is set from the viewpoint of preventing these occurrences.

[0071] [About speed relationships] The rewinding speed is faster than the conveying speed (the speed at which the foil is conveyed to the foil transfer section, also called the process speed). When the foil is transferred to the paper, a certain heating time is required to transfer the foil member onto the paper, so the conveying speed (feed speed) is limited. On the other hand, when the foil base paper is rewound, the above-mentioned heating time does not need to be taken into consideration, so the foil base paper can be wound at a high speed. Therefore, the rewinding speed can be increased during rewinding. In this way, productivity can be improved. In this embodiment, the conveying speed is 100 mm / s, the rewinding speed is 150 to 200 mm / s, and the rewinding speed is 1.5 to 2 times the conveying speed.

[0072] [Control flow in the first embodiment] Fig. 8 is a diagram showing a control flow of a rewinding operation in the first embodiment of the present invention. Using this diagram, the control performed by the control unit in the first embodiment of the present invention will be described. Note that in this embodiment, the form shown in Fig. 7 will be described as an example.

[0073] First, the preceding sheet S1 is transported toward the foil transfer unit (transfer unit) 420. At this time, the control flow in Fig. 8 starts (S001 in Fig. 8). The unit control 81 (control unit 80) also drives the heating drive 42b, which causes the foil supply roll 41 of the supply unit 410, the heating roller 42 of the foil transfer unit 420, the pressure roller 43, and the winding roll 44 of the winding unit 440 to rotate.

[0074] Next, the preceding sheet S1 passes through the foil transfer section 420, and at this time, the foil member 60f is transferred from the foil base paper 60 to the base image section 46 (S011 in FIG. 8).

[0075] Thereafter, the unit control 81 starts detecting whether the trailing edge of the preceding sheet S1 has passed the sheet trailing edge detection sensor 56 (S021 in FIG. 8). At this time, if the sheet trailing edge detection sensor 56 detects the trailing edge of the preceding sheet S1 (YES in S031 in FIG. 8), the unit control 81 proceeds to the next flow of S041. On the other hand, if the sheet trailing edge detection sensor 56 has not detected the trailing edge of the preceding sheet S1 (NO in S031 in FIG. 8), the unit control 81 returns to the flow of S021.

[0076] Then, in the flow of S041 in Fig. 8, the unit control 81 controls the supply drive 41b to rotate the foil supply roll 41 in the direction opposite to the winding operation, thereby starting the rewinding drive (reverse drive). Furthermore, the unit control 81 stops the winding roll 44, and stops feeding the foil base paper 60 to the winding roll 44 side (S051 in Fig. 8).

[0077] Thereafter, the unit control 81 controls the contact / separation means 43a to separate the pressure roller 43 from the heating roller 42 to release the pressure (S061 in FIG. 8). Thereafter, the unit control 81 controls the supply drive 41b to rotate the foil supply roll 41 in the direction of rewinding toward the supply section 410, thereby starting the rewinding operation of the foil base paper 60 (S071 in FIG. 8).

[0078] Thereafter, as the rewinding operation continues, the foil-used portion 60h reaches the foil usage detection sensor 57. Then, when the unit control 81 detects this foil-used portion 60h by the foil usage detection sensor 57 (S081 in FIG. 8), the unit control 81 stops the rewinding operation of the foil base paper 60 by the foil supply roll 41 (S091 in FIG. 8).

[0079] When the unit control 81 determines that foil transfer has been completed for all the papers (YES in S101 of FIG. 8), the control ends there (S111 of FIG. 8).

[0080] On the other hand, when the unit control 81 determines that the foil transfer is not yet completed for the paper to which foil transfer is to be performed (NO in S101 in FIG. 8), the subsequent paper S2 is transported toward the foil transfer section 420. The unit control 81 returns to flow S001 in FIG. 8, and controls to perform foil transfer onto the base image area 46 of the subsequent paper S2. As a result, the foil base paper 60 is supplied from the foil supply roll 41, and the winding operation in which it is wound up by the winding roll 44 is performed again.

[0081] <Regarding the Second Embodiment> FIG. 9 is a diagram for explaining the rewinding operation in an embodiment (second embodiment) according to the present invention. Using this diagram, another embodiment according to the present invention will be explained. In the embodiment according to FIG. 9, the preceding paper and the following paper on which different images are formed are sent to the foil transfer section. In addition, explanations of FIG. 9(a)-(c) will be omitted because the operation is the same as FIG. 7(a)-(c). Therefore, only FIG. 9(d), which is different from the first embodiment, will be explained below. In addition, the rotation direction of each roll is as shown by the solid arrow in the figure. In addition, the speed relationship, torque limit, tension relationship, etc. according to this embodiment are also the same as those of the first embodiment. In addition, the dashed line in the figure indicates the movement direction of the foil base paper.

[0082] [Operation in the second embodiment] First, the embodiment according to FIG. 9 is different from the first embodiment in that a base image portion 46a having a different image from that of the preceding sheet S1 is formed on the succeeding sheet S2. Then, as shown in FIG. 9(d), a rewinding operation is performed, and the base sheet 60 after the transfer is rewound toward the foil use detection sensor 57. Here, since the images formed on the preceding sheet S1 and the succeeding sheet S2 are different, the unit control 81 (control unit 80) refers to the image data on the succeeding sheet S2 and controls the succeeding sheet S2 to be transported toward the foil transfer unit (transfer unit) 420. Also, at this time, the unit control 81 detects the used portion (foil use portion 60h) of the foil base sheet 60 after the transfer by the foil use detection sensor 57 as shown in FIG. 9(d), and when the detection is possible, the above-mentioned transport is performed.

[0083] After that, the unit control 81 stops the rewinding operation of the foil base paper 60 by the foil supply roll 41. Then, in conjunction with this, in order to perform foil transfer onto the base image portion 46a of the succeeding sheet S2, the unit control 81 drives the heating drive 42b, and the winding operation is performed again to wind up the foil base paper 60 on the winding roll 44. Then, the steps (a) to (d) of Figure 9 are repeated.

[0084] In this embodiment, unlike the first embodiment, the images formed on the preceding sheet and the succeeding sheet are different, and the foil transfer images are also different, so the timing of foil transfer is different for both sheets. Therefore, for example, if the image data of the sheet sent to the foil transfer unit is not referenced each time, the timing of foil transfer may be shifted. Alternatively, if the foil-transferred portion of the foil base paper does not return to the specified position, it is assumed that the foil transfer will not be sufficiently rewound and foil transfer will start, resulting in unused foil material. In order to prevent these, the above-mentioned configuration is used. Note that if it is possible to transport the succeeding sheet S2 to the foil transfer unit 420, but the foil-used portion 60h is not detected by the foil use detection sensor 57, the unit control 81 controls the transport of the succeeding sheet S2 to wait and start transport after the foil use detection sensor 57 detects the foil use portion 60h.

[0085] [Control flow in the second embodiment] Fig. 10 is a diagram showing a control flow of a rewinding operation in the second embodiment of the present invention. Using this diagram, the control performed by the control unit in the second embodiment of the present invention will be described. Note that in this embodiment, the form shown in Fig. 9 will be taken as an example for explanation.

[0086] First, the preceding sheet S1 in Fig. 10 is transported toward the foil transfer unit (transfer unit) 420. At this time, the control flow in Fig. 10 starts (S002 in Fig. 10). The unit control 81 (control unit 80) also drives the heating drive 42b, which causes the foil supply roll 41 of the supply unit 410, the heating roller 42 of the foil transfer unit 420, the pressure roller 43, and the winding roll 44 of the winding unit 440 to rotate.

[0087] Next, the preceding sheet S1 passes through the foil transfer section 420, and at this time, the foil member 60f is transferred from the foil base paper 60 to the base image section 46 (S012 in FIG. 10).

[0088] Thereafter, the unit control 81 starts detecting whether the trailing edge of the preceding sheet S1 has passed the sheet trailing edge detection sensor 56 (S022 in FIG. 10). At this time, if the sheet trailing edge detection sensor 56 detects the trailing edge of the preceding sheet S1 (YES in S032 in FIG. 10), the unit control 81 proceeds to the next flow of S042. On the other hand, if the sheet trailing edge detection sensor 56 has not detected the trailing edge of the preceding sheet S1 (NO in S032 in FIG. 10), the unit control 81 returns to the flow of S022.

[0089] Then, in the flow of S042 in Fig. 10, the unit control 81 controls the supply drive 41b to rotate the foil supply roll 41 in the direction opposite to the winding operation, thereby starting the rewinding drive (reverse drive). Furthermore, the unit control 81 stops the winding roll 44, and stops feeding the foil base paper 60 to the winding roll 44 side (S052 in Fig. 10).

[0090] Thereafter, the unit control 81 controls the contact / separation means 43a to separate the pressure roller 43 from the heating roller 42 to release the pressure (S062 in FIG. 10). Thereafter, the unit control 81 controls the supply drive 41b to rotate the foil supply roll 41 in the direction of rewinding toward the supply section 410, thereby starting the rewinding operation of the foil base paper 60 (S072 in FIG. 10). Thereafter, as the rewinding operation is performed, the foil-used portion 60h moves toward the foil use detection sensor 57.

[0091] Then, the unit control 81 refers to the image data of the succeeding sheet S2 (S077 in FIG. 10). This is to allow the unit control 81 to wait for sending the sheet to the foil transfer section 420 if the rewinding of the foil base paper has not been completed in the next or subsequent control flow when a sheet for foil transfer is waiting. The unit control 81 also detects the foil-used portion 60h of the foil base paper 60 by the foil use detection sensor 57 (S082 in FIG. 10). At this time, if it is detected (YES in S092 in FIG. 10), the process proceeds to flow S102 in FIG. 10. If it is not detected (NO in S092 in FIG. 10), the rewinding operation continues (S097 in FIG. 10) and detection is performed again.

[0092] Then, when the foil use detection sensor 57 detects the foil used portion 60h, the unit control 81 stops the rewinding operation of the foil base paper 60 by the foil supply roll 41 (S102 in FIG. 10).

[0093] When the unit control 81 determines that foil transfer has been completed for all the papers (YES in S112 of FIG. 10), the control ends there (S122 of FIG. 10).

[0094] On the other hand, when the unit control 81 determines that the foil transfer is not yet completed for the paper to which the foil is to be transferred (NO in S112 in FIG. 10), the subsequent paper S2 is transported toward the foil transfer section (transfer section). The unit control 81 returns to flow S002 in FIG. 10 and controls to transfer the foil onto the base image section 46 of the subsequent paper S2. As a result, the foil base paper 60 is supplied from the foil supply roll 41 and the winding operation in which it is wound up by the winding roll 44 is performed again.

[0095] As described above, this embodiment includes the supply member 41 around which the sheet-shaped foil sheet member 60 having the foil member 60f and the holding member 60p that holds the foil member 60f is wound, the supply section 410 having the drive member 41b for driving the supply member 41 to rotate, the winding section 440 having the winding member 44 for winding up the foil sheet member 60, the transfer section 420 having a pair of rotors 42, 43 that rotate while sandwiching the foil sheet member 60 and forming the foil section 60g by transferring the foil member 60f onto the image 46 of the image-formed recording medium S, and the control units 80, 81 that control the drive member 41b, and by controlling the drive member 41b, after the foil member 60f has been transferred to the recording medium S by the transfer section 420 and before the conveyance of the foil sheet member 60 is stopped, the control units 80, 81 start the rotational drive of the supply member 41 in the direction opposite to the feed direction when transferring the foil member 60f to the recording medium S, thereby rewinding the foil sheet member 60 toward the supply member 41 side.

[0096] This makes it possible to prevent the foil sheet member from becoming wrinkled during the rewinding operation.

[0097] As described above, in this embodiment, the rewinding speed is faster than the transport speed.

[0098] This can improve productivity.

[0099] As described above, in this embodiment, when the limit torque of the rotating shaft of the winding member 44 is Tm and the limit torque of the rotating shaft of the supplying member 41 is Tk, the relationship is Tk>Tm.

[0100] This allows tension to be applied to the supply section side when the foil sheet member is rewound.

[0101] As described above, in this embodiment, the control units 80 and 81 have the torque limiting means 41 a and 44 a that can control the torque of the rotating shaft of the supply member 41 and the torque of the rotating shaft of the winding member 44 .

[0102] This can prevent the foil sheet member from being wrinkled.

[0103] As described above, in this embodiment, the torque limiting means are the torque limiters 41a and 44a.

[0104] This makes it possible to suppress wrinkles in the foil sheet member with a simple device configuration.

[0105] As described above, in this embodiment, the transfer unit 420 transfers the foil member 60f to the recording medium S by applying heat and pressure to the foil member 60f.

[0106] This makes it possible to form a foil portion on the image formed on the recording medium.

[0107] As described above, in this embodiment, the holding member 60p is transparent.

[0108] This makes it possible to detect the foil-used area by using a photosensor such as a transmission sensor, and the foil sheet member can be rewound and the rewind amount can be determined with a simple device configuration.

[0109] As described above, this embodiment has the detection means 57 for detecting the used area 60h of the foil member.

[0110] This makes it possible to perform the rewinding operation of the foil sheet member and determine the rewinding amount with a simple device configuration.

[0111] As described above, in this embodiment, the control units 80 and 81 determine the rewinding amount of the foil sheet member 60 by detecting the used area 60h of the foil member by the detection means 57.

[0112] This makes it possible to determine the amount of rewinding of the foil sheet member with a simple device configuration.

[0113] As described above, this embodiment has the contact / separation means 43a that enables at least one of the pair of rotors 42, 43 to be contacted or separated.

[0114] This makes it possible to perform foil transfer onto an image formed on the recording medium, and makes it possible to release pressure when rewinding the foil sheet member, for example.

[0115] As described above, in this embodiment, the control units 80, 81 rewind the foil sheet member 60 used during transfer onto the supply member 41 by separating one of the pair of rotating bodies 42, 43 using the contacting and separating means 43a.

[0116] This allows the unused area of ​​the foil sheet material to be unwound.

[0117] As described above, in this embodiment, the peeling section 45 that peels off the foil member 60g transferred onto the recording medium S and the support member 60p is provided on the downstream side of the transfer section 420 in the transport direction.

[0118] This allows the recording medium to which the foil has been transferred to to be separated from the base foil paper.

[0119] <Configuration with Cooling Transport Path> The present invention can also improve the foil transfer quality and use the foil material without waste by applying the following embodiment. Here, we will explain the embodiment. The rotation direction of each roll is as shown by the solid arrow in the figure. The dashed line in the figure indicates the movement direction of the foil base paper.

[0120] 11 is a diagram showing a foil forming section having a cooling transport path in an embodiment according to the present invention. This embodiment is different from the previous embodiments in that a cooling transport path 54 is provided after the foil transfer section 420. Therefore, this difference will be mainly described here. The other points are the same as the previous embodiments.

[0121] First, FIG. 11(a) shows a configuration in which a cooling conveying path 54 (one example of a conveying path) is provided after the foil transfer unit 420. The foil transfer unit 420 applies heat and pressure to enable the foil member 60f to be transferred from the foil base paper 60 to an image formed on the paper. The toner and other materials forming the image are in a molten state, and if the paper and the foil member are separated in this molten state at the separation unit 45, this may cause foil transfer failure. Therefore, the foil transfer device 40 according to this embodiment is provided with a cooling conveying path 54, which is a path of a length sufficient to sufficiently cool the foil-transferred paper S from the foil transfer unit 420 to the separation unit 45, to prevent the foil transfer failure.

[0122] 11(b) shows a configuration in which a cooling device 55 (an example of a cooling means) is provided in addition to the cooling transport path 54 after the foil transfer unit 420. In this way, it becomes possible to more efficiently cool the sheet S to which the foil has been transferred. Note that, for example, a cooling fan can be given as an example of the cooling device 55, but the present invention is not limited to this.

[0123] In addition, in the above embodiment, an example was given of a configuration in which a cooling conveying path 54 and a cooling device 55 are provided to cool the foil-transferred paper S, but the present invention is also applicable to a configuration in which a cooling device 55 is provided instead of the cooling conveying path 54 to cool the foil-transferred paper S.

[0124] [Foil loss and its reduction in a configuration with a cooling transport path] Fig. 12 is a diagram for explaining the loss of foil material in a foil part forming section having a cooling transport path. Using Fig. 12, the problems in the foil part forming section having the cooling transport path (related to Fig. 11) described above will be explained. Note that the configuration related to Fig. 12 has a cooling transport path 54 and a cooling device 55. The rotation direction of each roll is as shown by the solid arrow in the figure. The dashed line in the figure indicates the movement direction of the foil base paper.

[0125] 12, in the case of a configuration including a cooling transport path 54, the paper on which the foil has been transferred needs to be sufficiently cooled, so the paper needs to be transported the length of the cooling transport path. Therefore, the foil material is required for that length, and foil material other than that required for the image is also transported, resulting in loss of the non-required portion.

[0126] On the other hand, the present invention is configured such that after foil transfer to the paper S as shown in the above embodiment, and before the transport of the foil base paper 60 is stopped, the foil supply roll 41 is rotated in the direction opposite to the transport direction to rewind the foil base paper 60. By performing such an operation, the foil member can be rewound including the length of the cooling transport path. This improves the foil transfer quality by preventing the foil member from wrinkling, and reduces the loss of unused portions of the foil member, allowing the foil member to be used without waste. Note that the winding operation, rewinding operation, etc. in this embodiment are the same as those in the first embodiment described above.

[0127] As described above, in this embodiment, downstream of the transfer unit 420 in the feeding direction of the recording medium S, there is provided the transport path 54 capable of transporting the recording medium S with the toner image and the foil member 60f adhered thereto.

[0128] This prevents foil transfer failure.

[0129] As described above, this embodiment has the cooling means 55 for cooling the recording medium S in a state where it is adhered to the transport path 54.

[0130] This makes it possible to more efficiently cool the recording medium to which the foil has been transferred.

[0131] <Applicability to other areas> In the above embodiment, a configuration has been described in which the foil use detection sensor detects the foil-used portion when rewinding the foil base paper and controls the rewinding operation, but the foil use detection sensor according to the present invention can also be a line sensor, a reflective sensor, etc. Alternatively, the foil use detection sensor according to the present invention can be a sensor capable of detecting the amount of movement of the surface of the foil base paper, such as an encoder sensor, instead of a transmission sensor.

[0132] In the above embodiment, the foil base paper rewind drive (reverse rotation start) was started by detecting the rear end of the paper with the paper rear end detection sensor. However, the present invention can also use a sensor that detects the leading end of the paper instead of this sensor, or can refer to image data, or a combination of these. When detecting the leading end of the paper, the foil base paper rewind drive can be started earlier than when detecting the rear end of the paper, which can contribute to improving productivity.

[0133] The above description is merely an example, and the present invention provides unique effects for each of the following aspects.

[0134] [First aspect] The first aspect is a recording medium (e.g., a recording medium recording medium) having an image formed thereon, the recording medium (e.g., a recording medium ... For example, the recording medium recording apparatus includes a transfer unit (e.g., foil transfer unit 420) that forms a foil portion (e.g., transferred foil image 60g) by transferring the foil member onto an image (e.g., base image portion 46, 46a) of paper S), and a control unit (e.g., control unit 80, unit control 81) that controls the drive member, and the control unit controls the drive member to start rotating the supply member in the direction opposite to the feed direction when transferring the foil member to the recording medium after the foil member has been transferred to the recording medium in the transfer unit and before the transport of the foil sheet member is stopped, thereby rewinding the foil sheet member toward the supply member side.

[0135] [Second aspect] A second aspect is characterized in that in the first aspect, the rewinding speed is faster than the transport speed.

[0136] [Third aspect] A third aspect is characterized in that in the first or second aspect, when the limit torque of the rotating shaft of the winding member is Tm and the limit torque of the rotating shaft of the supply member is Tk, the relationship Tk>Tm holds.

[0137] [Fourth aspect] A fourth aspect is characterized in that in the third aspect, the control unit has a torque limiting means (e.g., torque limiters 41a, 44a) that can control the torque of the rotating shaft of the supply member and the torque of the rotating shaft of the winding member.

[0138] [Fifth aspect] A fifth aspect is the fourth aspect, characterized in that the torque limiting means is a torque limiter.

[0139] [Sixth aspect] A sixth aspect is any one of the first to fifth aspects, characterized in that the transfer unit transfers the foil member to the recording medium by applying heat and pressure to the foil member.

[0140] [Seventh aspect] A seventh aspect is any one of the first to sixth aspects, characterized in that the holding member is transparent.

[0141] [Eighth aspect] The eighth aspect is characterized in that in any of the first to seventh aspects, the device further comprises a detection means (for example, foil use detection sensor 57) for detecting a used area of ​​the foil member (for example, foil used portion 60h).

[0142] [Ninth aspect] A ninth aspect is the eighth aspect, characterized in that the control unit determines the rewinding amount of the foil sheet member by detecting a used area of ​​the foil member with the detection means.

[0143] [Tenth aspect] A tenth aspect is characterized in that in any one of the first to ninth aspects, the device further comprises a contact / separation means (for example, contact / separation means 43a) that enables at least one of the pair of rotors to be contacted or separated.

[0144] [Eleventh aspect] An eleventh aspect is characterized in that, in the tenth aspect, the control unit rewinds the foil sheet member used during transfer onto the supply member by separating one of the pair of rotating bodies using the contact / separation means.

[0145] [12th aspect] The twelfth aspect is characterized in that, in any of the first to eleventh aspects, a peeling section (e.g., a separation section 45) is provided downstream in the transport direction of the transfer section, which peels off the foil member transferred to the recording medium from the support member.

[0146] [13th aspect] The thirteenth aspect is characterized in that, in any of the first to twelfth aspects, a transport path (e.g., a cooling transport path 54) capable of transporting the recording medium in a state in which the toner image and the foil member are adhered is provided downstream of the transfer section in the feed direction of the recording medium.

[0147] [14th aspect] A fourteenth aspect is characterized in that in the thirteenth aspect, a cooling means (for example, a cooling device 55) is provided on the transport path to cool the recording medium in the adhered state. [Explanation of symbols]

[0148] 1. Color printer 2. Device body 3 Process cartridge 4 Photoconductor drum 5. Charging device 6. Developing device 7 Photoconductor cleaning device 8 Optical Unit 9 Intermediate transfer belt 10 Intermediate transfer unit 11 Drive roller 12, 13 Driven roller 14 Tension roller 15 Secondary transfer opposing roller 16 Primary transfer roller 17 Secondary transfer roller 18 Belt cleaning device 19 Transcription section 20 Fixing device 20 20a Heating belt 20a1 Heating roller 20a2 Drive roller 20a3 Belt member 20b Pressure roller 21 Transport Conveyor 22 Paper feed section 23,24 Paper feed cassette 25,26 Paper feed roller 27 Transport roller pair 28 Registration roller pair 29 Toner bottle 30 Discharge roller pair 31 Output tray 32 Paper ejection path 32 33 Switching Claw 34 First Re-Transportation Route 35 Switchback Passage 36 Second Re-Transportation Path 37 Reversing conveyor section 38 Switching Claw 39 Sheet conveying member 40 Foil transfer device (foil forming section) 41 Foil supply roll (supply roll) 41a Torque limiter 41b Supply drive 42 Heating roller 42a Heating section 42b Heating drive 43 Pressure roller 43a Approach / separation means 44 Winding roll 44a Torque limiter 44b Drive gear 45 Separation part 46 Base image section (image section) 46a Different base image section 48 Circulating Transport Route 49 Switching Claw 50 Laura Vs. 53 Guide roller 54 Cooling conveyor 55 Cooling device 56 Paper trailing edge detection sensor 57 Foil use detection sensor 60 Foil base paper 60a polyester film (base film) 60b Release layer 60c color layer 60d special vapor deposition layer 60e adhesive layer 60f Foil material 60g Transferred foil image 60h Foil area 60p original paper 60t Bent foil base paper 80 Control section 81 Unit Control 82 Memory 83 CPU 84 I / F interface 90 PC 120 Detection Group 200 Imaging Unit 410 Supply section 420 Foil Transfer Section (Transfer Section) 440 Winding section [Prior art documents] [Patent documents]

[0149] [Patent Document 1] JP 2018-62156 A

Claims

1. a supply section including a supply member around which a sheet-shaped foil sheet member having a foil member and a holding member for holding the foil member is wound, and a drive member for driving the supply member to rotate; a winding section having a winding member for winding up the foil sheet member; a transfer unit that includes a pair of rotors that rotate while sandwiching the foil sheet member therebetween, and that forms a foil portion by transferring the foil member onto an image formed on a recording medium; A control unit for controlling the driving member, The control unit controls the driving member to start rotating the supply member in a direction opposite to the feed direction when transferring the foil member to the recording medium, and before stopping the transport of the foil sheet member, thereby rewinding the foil sheet member toward the supply member side, after the foil member has been transferred to the recording medium in the transfer unit.

2. 2. The image forming apparatus according to claim 1, wherein the rewinding speed is faster than the transport speed.

3. 2. The image forming apparatus according to claim 1, wherein when a limit torque of the rotation shaft of the take-up member is Tm and a limit torque of the rotation shaft of the supply member is Tk, a relationship of Tk>Tm is satisfied.

4. 4. The image forming apparatus according to claim 3, wherein the control section has a torque limiting section capable of controlling a torque of the rotating shaft of the supply member and a torque of the rotating shaft of the take-up member.

5. 5. The image forming apparatus according to claim 4, wherein the torque limiting means is a torque limiter.

6. 2. The image forming apparatus according to claim 1, wherein the transfer section transfers the foil member to the recording medium by applying heat and pressure to the foil member.

7. 2. The image forming apparatus according to claim 1, wherein the holding member is transparent.

8. 2. The image forming apparatus according to claim 1, further comprising a detection means for detecting a used area of ​​the foil member.

9. 9. The image forming apparatus according to claim 8, wherein the control unit determines the amount of rewinding of the foil sheet member by detecting a used area of ​​the foil member with the detection means.

10. 2. The image forming apparatus according to claim 1, further comprising a contacting / separating means for making at least one of the pair of rotating bodies contactable and separable.

11. 11. The image forming apparatus according to claim 10, wherein the control section rewinds the foil sheet member used during transfer onto the supply member by causing the contact / separation means to separate one of the pair of rotating bodies.

12. 2. The image forming apparatus according to claim 1, further comprising a peeling section, downstream of the transfer section in the transport direction, for peeling off the foil member transferred onto the recording medium from the support member.

13. 2. The image forming apparatus according to claim 1, further comprising a transport path capable of transporting the recording medium with the toner image and the foil member adhered thereto, the transport path being disposed downstream of the transfer portion in a feeding direction of the recording medium.

14. 14. The image forming apparatus according to claim 13, further comprising a cooling means for cooling the recording medium in the adhered state on the transport path.

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