JP2006347166A - Thermal fixing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact image forming device capable of achieving an optimum transfer by uniform heating. <P>SOLUTION: The thermal fixing device comprises a both-side contact roller which transports a recording target medium in a pressureless state in a heating section of the device. The both-side contact roller has a structure with an upper roller 55T coming into contact with the upper surface of the recording target medium and a lower roller 55B coming into contact with the lower surface of the recording target medium. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the present invention, a sheet-like recording medium having a base material and a permeation layer on which image information to be transferred to the fixing layer on the surface of the base material is heated is printed on the permeation layer with sublimation ink. The present invention relates to a heat fixing device including a heating unit that transfers and fixes the image information to a fixing layer.

  There exists what is described in patent document 1 as a heat fixing apparatus comprised as mentioned above. In Patent Document 1, a colored base layer (fixing layer of the present invention) that also serves as a rust-preventing layer is formed on a metal substrate (substrate of the present invention), and an acrylic resin or a transparent resin layer is formed thereon. A transparent resin layer made of polyester resin or urethane resin is formed, and an ink jet receiving layer (permeation layer of the present invention) using porous alumina or the like is formed thereon to constitute a metal decorative body. A colored pattern is formed by ink jet printing using a sublimation colorant on the ink jet receiving layer of the metal decorative body. Thereafter, the metal decorative body is heated by a heating furnace or a hot press to sublimate the sublimation coloring material of the ink jet receiving layer and enter the transparent resin layer, and the colored pattern formed on the ink jet receiving layer is the transparent receiving layer. Formed. Next, after the ink jet receiving layer is softened with warm water, the entire surface of the ink jet receiving layer is removed by wiping with a cloth or the like, thereby completing a metal decorative body on which a colored pattern is formed.

  Also, a flexible resin sheet is used as a base material, a fixing layer is formed on the surface of the base material, and a permeation layer (having the same function as the receiving layer) is formed on the surface of the fixing layer. However, a recording medium for transferring and fixing recording information printed with sublimation ink on the permeation layer to the fixing layer by heating is under development, and this recording medium is used for the permeation layer of the recording medium. On the other hand, an apparatus has not been developed that performs a continuous process of printing recorded information with a sublimable ink and then sublimating the sublimable ink by heating to transfer and fix the recorded information on the fixing layer.

Japanese Patent Laid-Open No. 10-297197

  Considering the heat fixing device, for example, in the case where a flexible resin sheet is used as the base material of the recording medium, when biased heating is performed by this device or when biased force is applied. It is also conceivable that the substrate loses strain flatness when heated. In particular, when uneven heating is performed, transfer proceeds in a region where the temperature is high, and transfer is suppressed in a region where the temperature is low, which leads to density unevenness and color unevenness in the transferred and fixed recording information. Become.

  Specifically, in the case of forming a transfer image on a fixing layer by sublimating sublimable ink by heating, the image is formed on silver salt photographic paper by using a fluororesin as the fixing layer (printing) It is easy to make a product excellent in weather resistance as compared with a printed image or an image formed (printed) by an ink jet printer, and can be used for outdoor signs and stickers and seals used outdoors. In addition, when this type of recording medium is used outdoors, it is effective to use a PET (polyethylene terephthalate) resin sheet that is relatively inexpensive, excellent in water resistance and smoothness as the base material. Since this PET resin is thermoplastic, when the recording medium is heated, for example, when the recording medium is sandwiched between heating-type pressure rollers and transported, the heat is applied. , Unevenness of the pressing force in the axial direction between the pressing rollers, and imbalance in temperature and pressure acting on the recording medium due to imbalance in temperature distribution on the surface of the pressing roller, Therefore, there is a demand for a technique capable of generating density unevenness and color unevenness in a transferred image and the like and capable of performing uniform heating. In particular, when heating a thick recording medium, it is important to perform uniform heating from both the front and back sides. However, in the case of supplying heated air to both the front and back sides of the recording medium, an electric heater, fan, air supply system And the like are required to be disposed at positions sandwiching the transport path, and the entire apparatus becomes large. Improvement is also desired in this respect.

  An object of the present invention is to reduce the size of an image forming apparatus that realizes optimum transfer by uniform heating.

A feature of the present invention is that a sublimable ink is formed on a permeation layer by heating a sheet-like recording medium having a base material and a permeation layer on which image information to be transferred to the fixing layer on the surface of the base material is printed. In the thermal fixing device including a heating unit that transfers and fixes the image information printed in the fixing layer,
The heating unit includes a transport mechanism that transports the recording medium along a transport path, and a heating mechanism that heats the recording medium transported by the transport mechanism. A heating plate disposed in the lower part, and an air heating unit configured to supply heated air from above the conveyance path,
An upper roller that contacts the upper surface of the recording medium, and a lower roller that contacts the lower surface of the recording medium at a position displaced in the transport direction of the recording medium with respect to the upper roller. The double-sided contact roller is provided, and the recording medium is conveyed in a non-pressing state by the double-sided contact roller.

  With this configuration, by transporting the recording medium to the transport mechanism, the lower surface of the recording medium is heated by the heating plate disposed at the lower part of the transport path of the transport mechanism, and at the same time, at the upper part of the transport path. The upper surface is heated by contact with the heated air supplied from the arranged air heating unit. That is, when transporting the recording medium, the heat acts on the lower surface of the recording medium while the recording medium moves with respect to the heating plate. Can be heated on average. Further, since the recording medium is conveyed in a non-pressure contact state by the double-sided contact roller composed of the upper roller and the lower roller in the conveyance path, the conveyance in a state where no strong pressure is applied to the recording medium is realized. As a result, an image forming apparatus that realizes optimum transfer by uniform heating without applying a strong pressure to the recording medium is configured in a small size.

  In the present invention, the pair of upper rollers and the single lower roller constitute the double-sided contact roller, and the outer peripheral surface of the upper roller in a direction view along the conveyance direction of the recording medium; An interval substantially equal to the thickness of the recording medium may be set between the lower roller and the outer peripheral surface.

  With this configuration, the recording medium can be transported by applying a transport force in a state where the upper roller and the lower roller are in light contact with the recording medium.

  In the present invention, the upper surface of the heating plate is formed flat, and an upper surface contact roller that is in contact with the upper surface of the recording medium and is conveyed in a non-pressure-contact state as the conveying mechanism at an upper position of the heating plate. You may prepare.

  With this configuration, it is possible to perform conveyance without applying a strong pressure to the recording medium on the upper surface of the heating plate.

  In the present invention, an interval substantially equal to the thickness of the recording medium may be set between the outer peripheral surface of the upper surface contact roller and the heating plate in a direction view along the conveyance direction of the recording medium. .

  With this configuration, on the upper surface of the heating plate, the upper surface contact roller is in light contact with the upper surface of the recording medium, and the recording medium can be transported by applying a transport force.

  In the present invention, the air heating unit includes a cross flow fan that sends out heated air heated by an electric heater, and the heated air sent from the cross flow fan is transferred in the transport direction of the recording medium in the transport path. You may comprise so that it may flow toward the upstream of the said conveyance direction from the downstream of this.

  With this configuration, it is possible to heat the recording medium transported along the transport path by bringing heated air sent from the downstream side to the upstream side in the transport direction into contact with the recording medium.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, an image forming apparatus Q that prints image information transferred from an image processing apparatus P with a sublimation ink on a recording medium M, cuts it to a print size, fixes it by heating, and sends it out. Has been.

  The image processing apparatus P includes a general-purpose computer 1, a monitor 2, a keyboard 3, and a mouse 4, and a film scanner 6 that photoelectrically converts image information of a developed silver salt type photographic film 5 and a digital signal stored on a medium. And a media drive 7 inside the computer so as to retrieve the recorded information. The media drive 7 is a generic term for drives that extract information from not only disk-shaped media such as CDs, CD-Rs, and MOs but also semiconductors such as compact flash and smart media. Shows a media drive for reading CD and CD-R information.

  As shown in FIG. 4, the recording medium M is made of PET (polyethylene terephthalate) and has a polyvinyl alcohol resin as a resin having affinity for sublimation ink with respect to the surface of the film-like substrate 11. The fixing layer 12 is formed of a polyvinyl acetal resin or the like, and a thin film-like penetrating layer 13 such as a fluororesin or a silicon resin that has no affinity for the sublimation ink can be peeled off on the surface of the fixing layer 12. The recording medium M is superposed and configured as a flexible sheet as a whole. The recording medium M is printed with an image of sublimation ink on the permeable layer 13, and then heat-treated, whereby the ink of the permeable layer 13 is printed. Sublimates and moves to the fixing layer 12 to fix and form image information on the surface of the substrate 11, and after the image information is transferred and fixed, the permeation layer 13 is peeled off in the form of a film. It has become one to expose the clear image formed in the fixing layer 12 of the surface of the substrate 11 by removing Te. Further, when the recording medium M has a property that the material of the base material 11 has an affinity for the sublimation ink, the surface of the base material 11 can be used as the fixing layer 12 as it is.

  As shown in FIGS. 1 to 3, the image forming apparatus Q includes a printing unit Q1 that prints image information on a recording medium M, and a recording medium on which image information is printed with sublimation ink in the printing unit Q1. A loop forming unit Q2 for temporarily storing M and a heat fixing unit Q3 (an example of a heat fixing device) to which the recording medium M is sent from the loop forming unit Q2 are configured. In this image forming apparatus Q, the conveyance speed of the recording medium M in the thermal fixing unit Q3 is lower than the conveyance speed of the recording medium M in the printing unit. A loop forming portion Q2 is disposed at an intermediate position with respect to the heat fixing portion Q3, and the printing portion Q1, the loop forming portion Q2, and the heat fixing portion Q3 are configured as units that are separable from each other. The conveyance speed of the recording medium M in the thermal fixing unit Q3 is about 300 mm / min, and the conveyance speed of the recording medium M in the printing unit Q1 depends on the resolution of image information at the time of printing and the width of the recording medium M. Although determined, the minimum speed is higher than the transport speed of the recording medium M in the thermal fixing portion Q3.

[Print section]
The printing unit Q1 includes a transport mechanism A including a plurality of pressure-bonding-type transport rollers 21 so as to feed the roll-shaped recording medium M to the inside of the main body case 20, and the transport mechanism A horizontally. An ink jet print head 22 that prints image information on a recording medium M that is conveyed in the direction, a cutting mechanism B that is formed integrally with the print head 22, and a print control device 23 that controls them. The main body case 20 is supported by the support legs 27 so that the recording medium M on which the image information is printed is sent out in a horizontal direction at a relatively high position.

  The transport mechanism A includes a pre-transport mechanism A1 that transports the roll-shaped recording medium M to a portion of the print head 22, and a post-transport mechanism A2 that transports the recording medium M from the portion of the print head 22 to the discharge port 20A. The front transport mechanism A1 and the rear transport mechanism A2 are each configured to be independently driven by a stepping motor type transport motor (not shown). The print head 22 is guided by a pair of guide rods 24 provided in a posture (position along the main scanning direction) orthogonal to the conveyance direction (sub-conveyance direction) of the recording medium M, and is a stepping motor type. The sublimation ink of the ink cartridge 25 that is supported so as to be reciprocally movable in the main scanning direction by a driving force from a main scanning motor (not shown) and is detachable with respect to the print head 22 is ejected from a piezo element or the like. The mechanism 26 is configured to print image information from a nozzle (not shown).

  The cutting mechanism B includes a blade body 28 that is switchable between a position that protrudes toward the recording medium M with respect to the print head 22 and a position that retreats in a direction away from the recording medium M. A switching motor 29 is provided for switching the position of the blade body 28 via a cam feed or screw feed mechanism (not shown).

  In addition, as the ink of the ink cartridge 25, six colors using two colors of intermediate colors in addition to at least four colors of cyan (C), magenta (M), yellow (Y), and black (K) are used. The sublimation ink used in this embodiment starts sublimation at about 80 ° C., and as described above, the recording medium M having the film-like base material 11 made of PET has a temperature of 180 ° C. An optimum transfer state is obtained by heating for about 2 minutes. This sublimable ink can be easily sublimated at about 170 ° C. to 200 ° C., and can be transferred and fixed by heating for about 1 minute at 200 ° C. and for about 5 minutes at 170 ° C. Become.

  With this configuration, when the printing unit Q1 prints image information on the recording medium M, the print control device 23 operates the transport mechanism A to move the recording medium M to the portion of the print head 22. Next, the print head 22 is controlled to spray sublimation ink onto the permeation layer 13 of the recording medium M to print image information. When printing image information in this way, the print head 22 is operated in the scanning direction with the conveyance of the recording medium M stopped, and sublimation ink is sprayed onto the recording medium M. By this scanning, the print head When 22 reaches the operating end, the front conveyance mechanism A1 and the rear conveyance mechanism A2 are synchronously driven at a constant speed, and the process of conveying the recording medium M by an amount corresponding to the print width in the print head 22 is repeatedly performed. . Next, in the recording medium M on which the image information is printed, when a portion to be cut, such as an intermediate position between the image information, is conveyed to the cutting position of the cutting mechanism B, the blade body 28 is projected to be printed. By operating the head 22, the recording medium M is separated, and thereafter, the post-transport mechanism A2 is operated, and control for feeding the separated recording medium M from the discharge port 20A is executed.

(Loop formation part)
As shown in FIG. 5, the loop forming portion Q2 includes a turn roller 31 having three driven rollers 30 at a central position, and a first loop forming mechanism L1 on the upper side of the conveyance with reference to the turn roller 31. And a second loop forming mechanism L2 on the lower conveyance side with reference to the turn roller 31, and a case 44 for receiving the recording medium M at the lower position thereof.

  The turn roller 31 is configured to be freely driven by a stepping motor type roller motor M31, and the three driven rollers 30 are brought into pressure contact with the outer periphery of the turn roller 31, thereby causing the recording medium M to have a relatively large angle. Thus, it also functions to be able to remove the winding wrinkles of the recording medium M by being wound around the turn roller 31.

  The first loop forming mechanism L1 further guides the recording medium M discharged from the discharge port 20A of the printing unit Q1 downward, and the recording medium M guided downward by the introduction guide 32. A first fixed guide 33 that guides downward and a first movable guide 34 that is disposed opposite to the first fixed guide 33 are provided, and the first movable guide 34 can swing around a swing shaft 34A at the upper end. The output gear 36 of the first motor M34 is engaged with the first sector gear 35 provided on the swing shaft 34A, and the first movable guide 34 is driven by the drive of the first motor M34. It is possible to switch between a closed posture indicated by a solid line and an open posture indicated by a virtual line in the figure.

  The second loop forming mechanism L2 includes a second fixed guide 37 that guides the recording medium M sent from the first loop forming mechanism L1 via the turn roller 31 to the heat fixing portion Q3, and a second fixed guide 37. And a pressure-feed type supply roller 39 for feeding the recording medium M to the heat fixing portion Q3, and the second movable guide 38 is arranged around the swing shaft 38A at the upper end. The output gear 41 of the second motor M38 is engaged with the sector gear 40 provided on the swinging shaft 38A, and the output gear 42 of the supply motor M39 for driving the supply roller 39 is supplied. It is engaged with an input gear 43 provided at the shaft end of the roller 39, and the second movable guide can be switched between a closed posture shown by a solid line and an open posture shown by a virtual line in the drawing by driving a second motor M38. And Rotates the feed roller 39 by driving the feed motor M39, the recording medium M from the loop forming section Q2 be freely supplied to the heat fixing unit Q3.

  In the loop forming portion Q2, sensors (not shown) for determining the presence / absence of the recording medium M are arranged at various locations along the conveyance path of the recording medium M, and a control device (not shown) is provided. The control described below is executed by this control device. That is, when the recording medium M is discharged from the discharge port 20A of the printing unit Q1, the first movable guide 34 is set to the closed posture shown by the solid line in the drawing and the turn roller 31 is rotated at a low speed. When the leading end of the recording medium M is guided from the introduction guide 32 to the turn roller 31 and it is confirmed that the leading end of the recording medium M is held by pressure by the turn roller 31 and the driven roller 30, the turn roller 31. Is stopped, the first movable guide 34 is switched to the open posture shown by the phantom line in the figure, and the recording medium M is stored in the form of hanging down in the space of the first loop forming mechanism L1. Next, when the rear end of the recording medium M sent out from the printing unit Q1 is detected, the turn roller 31 and the supply roller 39 are in a state where the second movable guide 38 is set in the closed posture shown by the solid line in FIG. Driving is started, the leading end of the recording medium M is sent to the supply roller 39 of the second loop forming mechanism L2, and the leading end portion of the recording medium M is pressure-bonded by the supply roller 39 to be recorded on the recording medium M in the heat fixing portion Q3. The second movable guide 38 is switched to the open position shown by the phantom line in the drawing while performing the operation of feeding the heat fixing unit Q3 at a speed equal to the conveying speed of the first loop, and then the turn roller 31 is rotated at a high speed to rotate the first loop. Control is performed to store the recording medium M stored in the forming mechanism L1 in such a manner that the recording medium M hangs down in the space of the second loop forming mechanism L2. As described above, when the recording medium M of the first loop forming mechanism L1 is sent to the second loop forming mechanism L2, the recording medium M from the printing unit Q1 is introduced into the first loop forming mechanism L1 in the same manner as described above. Control begins.

  The loop forming portion Q2 is provided with a manual feed portion composed of a pair of guide plates 45 for directly supplying the recording medium M from the outside to the heat fixing portion Q3. The recording medium M on which the image information is formed can be heated and fixed by a printer or the like set at a position separated from the apparatus Q. The introduction guide 32 can be manually switched to the discharge posture shown by the phantom line in the drawing. By switching to this discharge posture, the recording medium M printed by the printing unit Q1 and the normal ink can be switched. Print paper printed with (non-sublimable ink) can be taken out. In addition, when the recording medium M is being conveyed in the loop forming unit Q2, the manual supply unit is provided with a shutter that is opened and closed by a control signal so that the recording medium M cannot be introduced from the manual supply unit. It is also possible to provide a lamp that indicates to the operator that the recording medium M exists in the forming portion Q2.

(Thermal fixing part)
As shown in FIG. 2 and FIGS. 6 to 9, the heat fixing portion Q <b> 3 has a heating case 51 made of a heat insulating material for heating the recording medium M inside the main body case 50, and heats the heating case 51. A blower case 52 (an example of an air heating unit) made of a heat insulating material disposed at an upper position of the heating case 51 so as to supply air, and the recording medium M sent out from the heating case 51 and in contact with the recording medium M A flattening portion D for flattening and a support leg 53 for supporting the main body case 50 are provided. The heating case 51 and the blower case 52 constitute a heating unit.

  In the heating space R formed inside the heating case 51, a pair of pressure-bonding type introduction rollers 54 is disposed at the position of the introduction portion of the recording medium M, and a lower conveyance side than the introduction rollers 54. A plurality of double-sided contact rollers 55 that contact the upper surface and the lower surface of the recording medium M on the side and apply a conveying force, and a plurality of upper surface contact rollers 56 that contact the upper surface of the recording medium M and apply a conveying force And a flat guide body 57 (of a heating plate) that guides the lower surface of the recording medium M in contact with the lower surface of the conveying path of the recording medium M in the heating conveyance mechanism. One example) is arranged at the transport upper position and the transport lower position, and a sheet heater 58 for heating the guide body 57 is provided on the lower surface side of the guide body 57. The double-sided contact roller 55 includes a pair of upper rollers 55T and a single lower roller 55B in a staggered arrangement as viewed from the side (in the direction along the axis) and along the conveyance direction of the recording medium M. A distance approximately equal to the thickness of the recording medium M is set between the outer peripheral surface of the upper roller 55T and the outer peripheral surface of the lower roller 55B in a direction view, and the upper roller 55T and the lower roller 55B are connected to the recording medium. In this state, the conveying force is applied while lightly contacting M. Since the recording medium M is conveyed in contact with the double-sided contact roller 55, even when the recording medium M is thermally expanded in the width direction, the recording medium M is hardly distorted. Since the contact roller 55 is arranged in a state of lightly contacting the recording medium M, variations in the temperature distribution of the recording medium M are also avoided. The positional relationship between the pair of upper rollers 55T constituting the double-sided contact roller 55 and the single lower roller 55B can be arbitrarily adjusted, thereby favorably adapting to the thickness of various recording media M. It is also possible. Further, the upper surface contact roller 56 is spaced substantially equal to the thickness of the recording medium M between the outer peripheral surface of the upper surface contact roller 56 and the upper surface of the guide body 57 when viewed in the direction along the conveyance direction of the recording medium M. In this arrangement, the upper surface contact roller 56 makes a slight contact with the upper surface of the recording medium M to apply a conveying force to the recording medium M.

The introduction roller 54, the double-sided contact roller 55, and the upper surface contact roller 56 are formed by forming foamed silicon rubber having excellent heat resistance on the outer periphery of the metal shaft members 54A, 55A, and 56A, respectively. Collectively called rollers. In the case of configuring this transport roller, it is also possible to configure the configuration in such a manner that the foamed silicon rubber tube is covered and fixed to the shaft members 54A, 55A, 56A. While lowering the hardness and lowering the pressure per unit area when pressure-bonded to the recording medium M, the frictional force is increased and reliable conveyance is realized. Further, the guide body 57 has a thermal conductivity of 0.02 cal / cm / sec / ° C. or more and a thermal expansion coefficient of 24 × 10 ⁻⁸ cm / ° C. or less, such as stainless steel, aluminum, titanium, etc. Those having a thickness of about 0.8 to 50 mm are used, and each of the pair of seat heaters 58 is configured by embedding a sheathed heater (not shown) in silicon rubber or the like having excellent heat resistance inside. A guide temperature sensor Sa for measuring the temperature of the guide body 57 is provided at the center position of each seat heater 58.

  Inside the blower case 52, a pair of electric heaters 60 formed in a plurality of rods so as to heat the air in the region divided into two in the width direction of the recording medium M, and the heated air to be sent. A pair of cross-flow fans 62 that are supported around an axis that is parallel to the width direction of the recording medium M and that are driven and rotated by the driving force of the fan motor 61 disposed at both ends in the width direction of the recording medium M are provided. Yes. On the lower surface side of the blower case 52, a heated air discharge port E is formed at a position directly below the cross flow fan 62, and a suction port F is formed at the upper transport position in the transport path of the recording medium M in the heating transport mechanism. Yes. A pair of air temperature sensors Sb are provided in the opening of the discharge port E in correspondence with the respective cross flow fans 62. In addition, the electric power supplied to the corresponding electric heater 60 is controlled so that each air temperature sensor Sb measures the temperature of 180 ° C., the temperature of 150 ° C. is measured by the guide temperature sensor Sa of the upper conveyance, and the lower conveyance side is measured. Control means (not shown) is provided for controlling the power supplied to each seat heater 58 so that the temperature of 180 ° C. is measured by the guide temperature sensor Sa.

  When the recording medium M is heated, the two fan motors 61 are driven at the same time, and the two electric heaters 60 are driven at the same time, so that the heated air heated inside the blower case 52 is heated from the discharge port E. The lower side position in the conveyance direction of the recording medium M in the internal space of the case 51 is sent out with a width exceeding the entire width in the width direction of the recording medium M, and this heated air is conveyed in the heating space R. It is made to flow toward the upper conveyance side along the path, sucked from the upper position in the conveyance direction of the recording medium M into the blower case 52 through the suction port F, heated by the electric heater 60, and then passed to the cross flow fan 62. Heating in a form in which air is circulated by supplying is realized. When heating is performed in this way, if a difference occurs in the temperatures measured by the pair of air temperature sensors Sb, the power supplied to the corresponding electric heater 60 is controlled based on the temperature difference, and The drive speed of the fan motor 61 is controlled to reduce the temperature difference.

  The flattening section D is arranged so that the recording medium M discharged from the discharge section is conveyed along the transport direction with respect to the discharge section of the heating transport mechanism (the part of the double-sided contact roller 55 at the transport end position). The curved conveyance path G is curved so that the lower conveyance side is directed downward, and the heating member 70 is in contact with the curved conveyance path G along the width direction of the recording medium M in the conveyance direction. Specifically, as shown in FIGS. 12 and 13, the curved conveyance path G is an extension of the path through which the recording medium M is sent out from the discharge unit so that the recording medium M is directed downward toward the lower conveyance side. On the upper side, the lower side includes a first guide surface 71 that is inclined in a direction away from the discharge unit, and a second guide surface 72 that is vertically oriented so as to feed the recording medium M downward, and a side wall 73 is provided. A guide body 74 that is formed in a space that opens downward by being provided and that adjusts the bending posture of the recording medium M by contacting the recording medium M is provided below the space.

  The heating member 70 is formed at a boundary portion between the upper wall 70a in a posture parallel to the direction in which the recording medium M is discharged from the discharge portion and the rear wall 70b in a vertical posture at a position connected to the upper wall 70a. And an electric heater 70d as a heating body for heating the corner 70c. The heating member 70 is provided with a flat portion temperature sensor Sc for measuring temperature, and the power supplied to the electric heater 70d is controlled so that the temperature measured by the flat portion temperature sensor Sc is maintained at 180 ° C.

  In the flattening section D, the recording medium M that has been heat-fixed inside the heating case 51 and then sent out in a horizontal posture is curved in a form of curling along the conveyance direction in the curved conveyance path G. Simultaneously with feeding downward, the corner 70c of the heating member 70 is positively brought into contact with the lower surface of the recording medium M, so that the force from the corner 70c is concentrated on the lower surface of the recording medium M. Even if the recording medium M is distorted during heating and fixing in the heating case 51 (heating space R), the corner portion 70c that is linear and heated to 180 ° C. is brought into contact with the heating case 51 (heating space R). Thus, the distortion is removed in a form that is corrected by contact with the substrate, and the flat recording medium M is sent out.

  At a position below the flattening portion D, there is provided a cloth stocker 80 in an inclined posture with the leading end side positioned below so as to receive the recording medium M sent out from the flattening portion D. As shown in FIGS. 1 and 2, the stocker 80 is set to have a width wider than the maximum width of the recording medium M that can be processed by the heat fixing unit, and static electricity is applied to the polyester fibers having excellent heat resistance. Conductive carbon fiber is woven to be removed, the upper end of the stocker 80 is supported by a support rod 81 in a horizontal position, the lower end is supported by a lower end rod 82, and both ends of the lower end rod 82 are heat fixing portions. The stocker 80 is supported by a stay 83 extending from the support leg 53, and the stocker 80 is set in an inclined posture in which the stocker 80 is displaced in a direction away from the heat fixing portion Q 3 toward the lower side.

  As shown in FIG. 2, the upper position of the flattening portion D is positioned above the flattening portion D so as to collect the upper position of the curved conveyance path G, the lower end opening, the leaked mist or gas, and the like. On the other hand, a duct 90 that opens downward is disposed, and an electric fan 91 that sucks mist and gas collected in the duct 90 and a removal unit H that removes mist and gas from the electric fan 91 by a removal mechanism 92 are provided. I have. This removal mechanism 92 is assumed to be one that removes odor by adsorbing mist and gas, one that removes odor by chemical reaction, and one that removes odor by the activity of microorganisms. It is considered to employ activated carbon, silica gel, zeolite, calcium silicate, ozone deodorizing device, photocatalytic device, and cleaning deodorizing device.

  A conveying roller excluding the introduction roller 54, a transmission system that transmits a rotational force to these conveying rollers, the guide body 74, and the flattening portion D in the conveying direction of the recording medium M with respect to the main body case 50. It is supported by a slide frame 100 that is configured to be slidable toward the lower side. That is, as shown in FIGS. 6 to 11, the slide frame 100 includes a pair of transmission cases 102 arranged on both sides of the conveyance roller, a bottom wall 101 arranged at a position where the transmission cases 102 are connected to each other, and these. The slide frame 100 is slid between a state where the slide frame 100 is pulled out to the rear side of the main body case 50 (see FIG. 8) and a state where the slide frame 100 is stored and set inside the main body case 50 (see FIG. 7). It is supported so that it can be switched by operation. In order to realize this sliding operation, a pair of guide rails 103 in a posture parallel to the conveyance direction of the recording medium M is supported, and the wheels 104 guided by the guide rails 103 are idle-supported on the transmission case 102. It is.

  A conveyance motor 106 is provided at a lower position of the main body case 50, an intermediate gear 108 meshing with the output gear 107 of the conveyance motor 106 is supported on the main body case side, and an input gear 109 meshing with the intermediate gear 108 is supported by the transmission case. It is supported on one side of 102. The transmission case 102 includes an input sprocket 110 that rotates integrally with the input gear 109, a sprocket 55S provided at the shaft end of the shaft member 55A of the lower roller 55B of the double-sided contact roller 55, and a shaft member of the upper surface contact roller 56. A sprocket 56S provided at the shaft end of 56A, an endless chain 112 that transmits power to these sprockets 110, 55S, and 56S; Built in. Furthermore, an interlocking gear 115 that engages with each other at the shaft end of the shaft member 55A of each roller so as to rotate the double-sided contact roller 55 synchronously with the transmission case 102 and the other transmission case 102 is incorporated. .

  As shown in FIGS. 10 and 14, a gear 120 that rotates integrally with the sprocket 55 </ b> S at the upper conveyance position of the recording medium M is provided, and a transmission gear 121 that meshes with the gear 120 is supported on the slide frame 100 side. The transmission gear 121 is engaged with a transmission gear 122 provided at the shaft end of the shaft member 54A of the introduction roller 54, and an interlocking gear 123 is provided that meshes with each shaft member 54A.

  As shown in FIGS. 7 and 8, a drawer connector 127 is provided between the lower surface position of the slide frame 100 and the frame 50 </ b> F of the main body case 50. The drawer connector 127 includes a fixed connector 127A supported on the frame 50F side of the main body case 50 and a slide connector 127B supported on the slide frame 100 side. The drawer connector 127 is pulled out by pulling out the slide frame 100. By separating and setting the slide frame 100 at the connecting position shown in FIG. The power supply to the seat heater 58 via the drawer connector 127 and the conduction and separation of the signal system to the guide temperature sensor Sa for measuring the temperature of the guide body 57 are possible.

  As shown in FIG. 14, a fitting hole 116 is formed at an upper position in the conveyance direction of the recording medium M in the slide frame 100, and the frame 50 </ b> F of the main body case 50 is formed with respect to the fitting hole 116. A positioning pin 117 that can be freely inserted and removed is projected. As shown in the figure, a lock arm 130 that is swingable around a support shaft 128 with respect to the frame 50F of the main body case 50 and urged in a locking direction by a torsion spring 129 is supported. The lock arm 130 is integrally formed with a lock piece 130 </ b> A and an operation portion 130 </ b> B operated by an operator at a distal end portion, and a contact portion 130 </ b> C is integrally formed with a base end portion of the lock arm 130. is there. The slide frame 100 includes a lock plate 131 having a lock hole 131A that engages with the lock piece 130A. A magnet 132A, a reed switch 132B, and a reed switch 132B are provided at portions facing the lock arm 130 and the lock plate 131. A proximity switch 132 is arranged. The proximity switch 132 is for electrically detecting the state of the lock arm 130 and is not shown in the drawing. However, when the reed switch 132B detects that the lock is released, the proximity switch 132 is connected to the power supply system. Electric power is configured to cut off the electric power supplied from the main body case side to the drawer connector 127 by operating an intervening relay (not shown).

  With this configuration, when the slide frame 100 is pulled out, the lock arm 130 is operated to the unlocking posture shown in FIG. By pressing the end, the slide frame 100 is slightly slid in the pull-out direction. In this state, the relay is activated to cut off the power to the drawer connector 127. In this state, the operator manually pulls out the slide frame 100, so that the drawer connector 127 is completely separated, the intermediate gear 108 and the input gear 109 are separated, and the transmission gear 121 and the driven gear 122 are separated. Thus, the transport system can be easily inspected and repaired, or the jam of the recording medium M can be easily removed. Thereafter, by pushing the slide frame 100 into the main body case, the intermediate gear 108 and the input gear 109 are engaged with each other, and the transmission gear 121 and the driven gear 122 are engaged with each other. Can be transmitted, and the drawer connector 127 can reach a connected state to transmit electric power and signals. The lock piece 130A of the lock arm 130 is connected to the lock hole of the lock plate 131 as shown in FIG. The slide frame 100 is fixed by engaging with 131A and reaching the locked state.

  Since the image forming apparatus Q is configured as described above, when the image forming apparatus Q forms an image on the recording medium M by transfer, the following control is executed. That is, the print head 22 is operated in a state where the transport mechanism A of the print unit Q1 is driven to transport the recording medium M to the position of the print head 22, and the sublimation ink is applied to the permeation layer 13 of the recording medium M. Print image information with. When image information is printed on the recording medium M in this way, if the image information to be printed is large, the leading end of the recording medium M on which the image information is printed is the print unit Q1. It is sent out from the discharge port 20A to the loop forming portion Q2. Further, when the recording medium M on which the image information is printed is cut in the printing unit Q1, the blade 28 is moved at the timing when the position to be cut of the recording medium M reaches the cutting position of the cutting mechanism B. By operating the print head 22 in the main scanning direction in the protruding state, the recording medium M is separated, and the cut portion of the recording medium M that has been sent out becomes the rear end of the recording medium M, and printing is performed. The cutting site inside the portion Q1 is the leading end of the recording medium M to be sent out next.

  When the recording medium M is sent out from the printing unit Q1, the leading end of the recording medium M is sent to the turn roller 31 at the center of the loop forming unit Q2, and the turn roller 31 and the driven roller 30. The recording medium M is stored in the first loop forming mechanism L1 in a state in which the recording medium M is hung down in a state where the recording medium M is pressed and held. An operation of sending the tip of the recording medium M held by pressure bonding to the supply roller 39 of the second loop forming mechanism L2 is performed, and after being held by pressure contact with the supply roller 39, the turn roller 31 is rotated at a high speed to perform the first rotation. The recording medium M stored in the loop forming mechanism L1 is sent to the second loop forming mechanism L2, and the recording medium M is stored in a form that hangs down in the second loop forming mechanism L2.In particular, in the loop forming portion Q2, the recording medium M is conveyed around the turn roller 31 and the winding direction of the recording medium M around the turn roller 31 is set in a roll shape in the printing portion Q1. Since the direction of winding of the recording medium M is opposite, the winding wrinkles of the recording medium M are effectively removed.

  Next, in the heat fixing part Q3, when the recording medium M is supplied from the supply roller 39 of the loop forming part Q2, the recording medium M is sent from the introduction roller 54 to the heating space R inside the heating case 51. In this heating space R, a conveying force is applied by contact with the conveying roller and is sent to the lower side in the conveying direction. In the heating case 51, the upper surface of the recording medium M is heated by contact with the heated air that is sent from the lower side to the upper side in the transport direction so as to reach the full width in the width direction of the recording medium M. At the same time, the lower surface of the recording medium M is heated by coming into contact with the guide body 57. In the heating case 51, the temperature of the heated air is higher at the lower side in the transport direction (180 ° C.) and the temperature of the guide body 57 on the lower side in the transport direction is higher (180 ° C.). , The temperature of the recording medium M is gradually increased, and when it reaches the lower level of the conveyance, the temperature is raised to an appropriate temperature, causing almost no distortion on the substrate 11 and thermal transfer that does not cause unevenness in image information. Is to be realized.

  The recording medium M that has been subjected to the thermal transfer is sent to the flattening portion D, and is curved in a curved conveyance path G having a first guide surface 71 and a second guide surface 72 as shown in FIG. By contacting the corner 70c of the heating member, the straight corner 70c contacts the entire width in the width direction of the recording medium M, so that some distortion is removed, and then received by the stocker 80. It is recovered in the form. It should be noted that the removal mechanism 92 disposed above the flattening portion D removes odors generated during heat fixing to create a comfortable working environment.

[Another embodiment]
In the present invention, in addition to the above-described embodiment, for example, as shown in FIG. 15, a manual feed unit 140 for feeding the recording medium M from the outside is formed on the upper surface of the main body case 50 in the thermal fixing unit Q3. It is also possible to form a supply path 141 that joins the recording medium M from the supply unit 140 to the transport mechanism in the thermal fixing unit Q3 (this alternative embodiment has the same function as the previous embodiment). Those having the same numbers and symbols as those in the embodiment are attached). With this configuration, the recording medium M printed using sublimation ink by a printer other than the printing unit Q1 can be easily supplied to the thermal fixing unit Q3.

Perspective view showing an image processing apparatus and an image forming apparatus Partially cutaway side view showing an image processing apparatus and an image forming apparatus Vertical section of the print section Vertical side view of the recording medium Longitudinal side view of loop forming part Perspective view of heat fixing part Vertical side view of heat fixing part Longitudinal side view of heat fixing part with slide frame slid Longitudinal front view of heat fixing part Perspective view showing an outline of the transmission system of the heating conveyance mechanism Longitudinal front view showing the arrangement of the transmission case of the heating transmission mechanism Longitudinal side view showing the structure of the flat part Perspective view showing structure of flattening portion Vertical side view showing the end of the slide frame at the connection position and the separation position Longitudinal side view showing a heat fixing part of another embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Base material 12 Fixing layer 13 Penetration layer 52 Air heating part 55 Double-sided contact roller 55T Upper roller 55B Lower roller 56 Upper surface contact roller 57 Heating plate 60 Electric heater 62 Crossflow fan M Recording medium

Claims (5)

Image information printed with sublimation ink on a permeation layer by heating a sheet-like recording medium having a base material and a permeation layer on which image information to be transferred to the fixing layer on the surface of the base material is printed A heat fixing device including a heating unit for transferring and fixing the toner to the fixing layer,
The heating unit includes a transport mechanism that transports the recording medium along a transport path, and a heating mechanism that heats the recording medium transported by the transport mechanism. A heating plate disposed in the lower part, and an air heating unit configured to supply heated air from above the conveyance path,
An upper roller that contacts the upper surface of the recording medium, and a lower roller that contacts the lower surface of the recording medium at a position displaced in the transport direction of the recording medium with respect to the upper roller. A thermal fixing device that includes the double-sided contact roller and conveys the recording medium in a non-pressing state by the double-sided contact roller.   The pair of upper rollers and the single lower roller constitute the double-sided contact roller, and the outer peripheral surface of the upper roller and the lower roller of the lower roller as viewed in the direction along the conveyance direction of the recording medium. The thermal fixing device according to claim 1, wherein an interval substantially equal to the thickness of the recording medium is set between the outer peripheral surface and the outer peripheral surface.   The upper surface of the heating plate is formed to be flat, and an upper surface contact roller is provided at the upper position of the heating plate as the transport mechanism and transports in a non-pressure contact state in contact with the upper surface of the recording medium. Item 3. The thermal fixing device according to Item 1 or 2.   4. The gap between the outer peripheral surface of the upper surface contact roller and the heating plate is set to be substantially equal to the thickness of the recording medium when viewed in the direction of conveyance of the recording medium. Thermal fixing device.   The air heating unit includes a cross flow fan for sending out heated air heated by an electric heater, and the heated air sent from the cross flow fan is sent from the downstream side in the transport direction of the recording medium in the transport path. The thermal fixing device according to claim 1, wherein the thermal fixing device is configured to flow toward an upstream side in the transport direction.

Images