Image heating equipment

Abstract

An image heating device includes: a first rotatable member and a second rotatable member configured to form a nip in which a toner image is fixed to a recording material; an air blowing mechanism; a channel configured to guide air from the air blowing mechanism toward one end of the first rotatable member relative to its longitudinal direction; and an opening and closing mechanism configured to open and close an air blowing port of the channel. The opening and closing mechanism includes a plurality of shutter members configured to cooperate with each other to close the air blowing port.

Description

[0001] This application is a divisional application of the invention patent application named "Image Heating Device", filed on November 20, 2018, and with national application number 201811379533.X. Technical Field

[0002] The present invention relates to an image heating device for heating a toner image on a recording material. The image heating device can be used in an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a multifunctional machine having multiple functions of these machines. Background Art

[0003] Conventionally, a fixing device (image heating device) for fixing a toner image formed on a recording material (sheet) under application of heat and pressure is installed in an image forming apparatus.

[0004] In such a fixing device, it is known that when an image is formed on a sheet having a width narrower than the maximum width sheet that can be introduced into the fixing device (hereinafter referred to as small-size paper), the temperature of an area that is part of a rotatable member (a longitudinal end area of ​​the rotatable member for heating the fixing device where the rotatable member does not contact the sheet) excessively rises.

[0005] Therefore, the fixing device disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2015-158600 employs a configuration in which the longitudinal end regions of a rotatable member, which may heat up, are cooled by blowing air. Specifically, a fan, a channel, and a baffle member (a baffle member configuration in which a single baffle member is provided on each side) are provided in each region on one end and the other end of the rotatable member relative to the longitudinal direction.

[0006] However, in the configuration disclosed in (JP-A) 2015-158600, the recent market demand, ie, compatibility with various width sizes, cannot be fully met. Summary of the Invention

[0007] According to one aspect of the present invention, an image heating device is provided, which includes: a first rotatable member and a second rotatable member, the first rotatable member and the second rotatable member being configured to form a clamping portion in which a toner image is fixed on a recording material; a blowing mechanism; a channel, the channel being configured to guide air from the blowing mechanism toward an end portion of the first rotatable member relative to a longitudinal direction of the first rotatable member; an opening and closing mechanism, the opening and closing mechanism being configured to open and close an air blowing port of the channel, wherein the opening and closing mechanism includes a plurality of baffle members configured to cooperate with each other to close the air blowing port.

[0008] According to another aspect of the present invention, there is provided an image heating device, comprising: a first rotatable member and a second rotatable member, the first rotatable member and the second rotatable member being configured to form a nip portion in which a toner image is fixed on a recording material; an air blowing mechanism; a first channel, the first channel being configured to guide air from the air blowing mechanism toward one end portion of the first rotatable member relative to a longitudinal direction of the first rotatable member; a first opening and closing mechanism, the first opening and closing mechanism being configured to open and close a first air blowing port of the first channel, wherein the opening and closing mechanism includes a plurality of baffle members configured to cooperate with each other to close the air blowing port; a second channel, the second channel being configured to guide air from the air blowing mechanism toward the other end portion of the first rotatable member relative to the longitudinal direction of the first rotatable member; and a second opening and closing mechanism, the second opening and closing mechanism being configured to open and close a second air blowing port of the second channel, wherein the second opening and closing mechanism includes a plurality of baffle members configured to cooperate with each other to close the air blowing port.

[0009] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Parts (a) and (b) of FIG. 1 are schematic diagrams respectively showing a fully closed state and a fully open state of a baffle member structure having two baffle members on each side.

[0011] Figure 2 is a schematic cross-sectional view showing the overall structure of the image forming apparatus in Embodiment 1.

[0012] Figure 3 It is a schematic perspective view of the appearance of the fixing device on the rear side, one end side, and the upper surface side.

[0013] Figure 4 It is a schematic perspective view of the appearance of the fixing device on the other end side.

[0014] Figure 5 It shows Figure 3 A schematic perspective view of a state of a fixing device with an air blowing cooling mechanism provided on an upper surface side of a device frame being removed from the fixing device.

[0015] Figure 6 It is along Figure 3 A schematic cross-sectional view of the fixing device taken along line (6)-(6).

[0016] Figure 7 yes Figure 5 A partially cutaway schematic front view of a fixing device.

[0017] Figure 8It is a schematic exploded perspective view of the fixing assembly (fixing member).

[0018] Figure 9 This is a block diagram of the main control system of the fixing device.

[0019] Figure 10 Viewed from the inlet (air intake) port side Figure 3 Exploded perspective view of the air blowing cooling mechanism.

[0020] Figure 11 Viewed from the air port side Figure 3 A perspective view of an inverted air blowing cooling mechanism, wherein the baffle mechanism is in a baffle member closed state.

[0021] Figure 12 yes Figure 11 Exploded perspective view of the air blowing cooling mechanism.

[0022] Figure 13 It is a perspective view showing only the shutter mechanism as viewed from the inside of the shutter mechanism.

[0023] Figure 14 is a perspective view showing the air blowing cooling mechanism portion, which is Figure 11 A portion of the air blowing cooling mechanism is removed from the baffle member, wherein the air blowing cooling mechanism portion is viewed from the air blowing port side.

[0024] Parts (a) and (b) of FIG. 15 are schematic diagrams of the shutter mechanism in a fully closed state and during an opening movement operation, respectively, as viewed from the inlet port side (inside the shutter mechanism).

[0025] Parts (a) and (b) of FIG. 16 are schematic diagrams of the shutter mechanism in a fully closed state and during an opening movement operation, respectively, as viewed from the air blow port side (outside of the shutter mechanism).

[0026] Figure 17 is a schematic diagram showing the relationship between the inner baffle member, the outer baffle member, and the channel.

[0027] Figure 18 Schematic diagram of the shutter mechanism as viewed from the inlet port side (inside the shutter mechanism), wherein the shutter member is in an open position substantially intermediate between the fully closed position and the fully open position.

[0028] Figure 19 Schematic diagram of the shutter mechanism viewed from the air blow port side (outside of the shutter mechanism), in which the shutter member is in an open position substantially intermediate between the fully closed position and the fully open position.

[0029] Parts (a) and (b) of FIG. 20 are schematic diagrams of the main parts of the air blowing cooling mechanism in Example 2 in the fully closed state and the fully open state, respectively.

[0030] Figure 21 This is a diagram of the air blowing cooling mechanism in Example 3.

[0031] Figure 22 It is a diagram of the air blowing cooling mechanism in Example 4 and is a view of the outer surface of the inner baffle member.

[0032] Figure 23 It is a diagram of the air blowing cooling mechanism in Example 4 and is a view of the inner surface of the outer baffle member.

[0033] Figure 24 It is a diagram of the air blowing cooling mechanism in Example 5 and is a view of the outer surface of the inner baffle member.

[0034] Figure 25 It is a diagram of the air blowing cooling mechanism in Example 5 and is a view of the inner surface of the outer baffle member.

[0035] Figure 26 is a diagrammatic representation of the gap between the inner and outer baffle members.

[0036] Parts (a) to (c) of FIG. 27 are diagrams of a jig used in the assembling method of the air blowing cooling mechanism in Example 6. FIG.

[0037] Parts (a) and (b) of Figure 28, Figure 29 、 Figure 30 and Figure 31 This is a perspective view for explaining the assembly process of the air blowing cooling mechanism.

[0038] Figure 32 is a perspective view of the drive pinion.

[0039] Figure 33 Schematic diagram showing the surface of the channel on the air blowing port side (channel lower surface).

[0040] Figures 34 to 40 This is a perspective view for explaining the assembly process of the air blowing cooling mechanism.

[0041] Parts (a) and (b) of Figure 41 are diagrams of reference examples in Embodiments 4 and 5.

[0042] Figure 42 This is a diagram of a reference example in Embodiment 6. DETAILED DESCRIPTION

[0043] The embodiments for implementing the present invention will be described in detail with reference to the accompanying drawings. The sizes, materials, shapes and relative arrangements of the constituent elements described in the following embodiments should be appropriately changed according to the structure and various conditions of the mechanism (device) to which the present invention is applied, and the scope of the present invention is not limited to the following embodiments.

[0044] <Example 1>

[0045] (Imaging equipment)

[0046] Figure 2 1 is a schematic cross-sectional view showing the overall structure of an example of an image forming apparatus A using electrophotography. In this embodiment, the image forming apparatus A is a monochrome printer that prints an image forming product on which a toner image is formed by performing an image forming operation corresponding to a print job input from an external host device 200 (e.g., a personal computer) to a control circuit portion (CPU) 100.

[0047] In the image forming apparatus A, an image forming section A1 for forming a toner image on a sheet-like recording material P (sheet) (as a recording medium) includes a drum-type electrophotographic photosensitive member (drum) 1 as an image bearing member. The drum 1 is driven to rotate at a predetermined circumferential speed in the clockwise direction indicated by the arrow. Furthermore, the image forming section A1 includes a charging roller 1a, a laser scanner 1b, a developing device 1c, a transfer roller 1d, and a cleaning device 1e as processing devices that can act on the drum 1 at the periphery of the drum 1 along the direction of drum rotation. The image forming operation and the electrophotographic method of the image forming section A1 are well known, and therefore description thereof will be omitted.

[0048] The recording material P is a sheet-like recording medium (medium) on which a toner image can be formed by an image forming apparatus. For convenience, sheet (paper)-related terms (e.g., sheet passing, sheet feeding, sheet discharge, sheet passing portion, and non-sheet passing portion) will be used to describe the processing of the recording material (sheet) P, but the recording material is not limited to paper.

[0049] One sheet P from among the plurality of sheets P housed in the sheet cassette 2 is separated and fed at predetermined control timing by the rotation of the feed roller 3. The sheet P passes through a path including a feed path a, a pair of registration rollers 4, and a feed path b, and is introduced into a transfer section (transfer nip) 5, which is the contact portion between the drum 1 and the transfer roller 1d, at predetermined control timing. While being nipped and fed at the transfer section 5, the sheet P then undergoes transfer of the toner image formed on the surface of the drum 1.

[0050] The sheet P emerging from the transfer section 5 is separated from the surface of the drum 1 and passes through a feed path c before being introduced into a fixing device (heating fixing device, image heating apparatus) 6, where the toner image (image) formed on the sheet (recording material) P is fixed to the sheet S under the application of heat and pressure. The sheet P emerging from the fixing device 6 passes through a feed path d and is discharged as an imaged product onto a discharge tray 7. In FIG1 , the direction of arrow Pa is the sheet feeding direction.

[0051] (Fixing device)

[0052] Here, for the fixing device 6, the front surface (side) is the surface (side) located on the side where the sheet P is introduced, the rear surface (side) is the surface (side) opposite the front surface (side), and left and right are left (L) and right (R) as viewed from the front. The longitudinal direction is the axial direction or generatrix direction of the rotatable member, and the short side direction is the direction perpendicular to the longitudinal direction. Top and bottom are top and bottom relative to the direction of gravity. These directions also apply to the components of the fixing device 6.

[0053] In addition, the upstream side and the downstream side are the upstream side and the downstream side with respect to the sheet feeding direction Pa. The one end side and the other end side are the one end side and the other end side with respect to the longitudinal direction. In this embodiment, the left side is the one end side (non-driven side, front side), and the right side is the other end side (driven side (side receiving driving force), rear side). The width of the sheet P is the sheet size on the sheet surface with respect to the direction perpendicular to the sheet feeding direction Pa.

[0054] Figure 3 1 and 2 are schematic perspective views of the outer appearance of the fixing device 6 on the rear side, one end side, and upper surface side. Figure 4 It is a schematic perspective view of the appearance of the fixing device 6 on the other end side. Figure 5 It shows Figure 3 1 is a schematic perspective view of a state of the fixing device 6 , with the air blowing cooling mechanism 30 provided on the upper surface side of the device frame being removed from the fixing device 6 . Figure 6 It is along Figure 3 A schematic cross-sectional view of the fixing device 6 taken along line (6)-(6). Figure 7 yes Figure 5 FIG. 1 is a partially cutaway schematic front view of the fixing device 6 . Figure 8 It is a schematic exploded perspective view of the fixing assembly. Figure 9 FIG. 6 is a block diagram of a main control system of the fixing device 6 .

[0055] The fixing device 6 is a film heating type image heating device. The fixing device 6 generally includes a fixing assembly (fixing member) 10 provided with a fixing film 13, a pressure roller (fixing member) 20 having elasticity, a (fixing) device frame (device housing) 25 accommodating these members 10 and 20, and an air blowing cooling mechanism 30. Hereinafter, the fixing assembly 10 is similarly referred to as the assembly 10. A clamping portion (fixing clamping portion) N ( Figure 6 and 7 ).

[0056] The nip N is a portion where the paper P bearing an unfixed toner image thereon is nipped and fed, whereby the toner image is fixed to the sheet P under application of heat and pressure. In the nip N, a fixing film (fixing belt) 13 contacts the surface of the sheet P bearing the unfixed toner image thereon.

[0057] like Figure 6 As shown, the assembly 10 is an assembly of a cylindrical (annular, endless belt-shaped) fixing film 13, a heater 11, a heat insulating holder 12, a pressing support (metal support) 14, and fixing flanges 15 (L, R). Figure 8 1 is an exploded perspective view of the assembly 10 , and the pressure roller 20 is also shown together with the assembly 10 .

[0058] (1) Fixing film

[0059] The fixing film (fixing belt, flexible sleeve, hereinafter referred to as film) 13 is a thin, annular heat transfer member having flexibility and heat resistance, and assumes a substantially cylindrical shape in its free state by its own elasticity.

[0060] The membrane 13 is a heat-resistant membrane having a thickness of 200 μm or less to enable rapid startup. The membrane 13 is formed of a heat-resistant resin material (e.g., polyimide, polyamide-imide, or PEEK (polyetheretherketone)) as a base material, or a pure metal having heat resistance and high heat conductivity such as SUS (stainless steel), aluminum, nickel, copper, or zinc, or an alloy of these metals.

[0061] When the base layer is made of a resin material, a heat-conducting powder such as boron nitride (BN), aluminum oxide, or aluminum may be mixed into the base layer to improve heat conductivity. Furthermore, to achieve a long-lasting fixing device, film 13 needs to have a total thickness of 100 μm or greater, providing sufficient strength and excellent durability. Therefore, the optimal total thickness of film 13 is 100 μm or greater and 200 μm or less.

[0062] Furthermore, in order to prevent deviation and ensure the separation performance of the sheet material P, a release layer made of a heat-resistant resin material (a fluorine-containing resin material such as PTFE, PFA, FEP, ETFE, CTFE, or PVDF or a silicone resin material) having good release performance is formed as a surface layer, either alone or in combination, and applied to the base layer. In this embodiment, the surface layer is composed of a material containing at least PTFE and PFA.

[0063] Here, PTFE is polytetrafluoroethylene, PFA is tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, FEP is tetrafluoroethylene-hexafluoropropylene copolymer, ETFE is ethylene tetrafluoroethylene copolymer, CTFE is polychlorotrifluoroethylene, and PVDF is poly(vinylidene fluoride).

[0064] As a coating method, after etching, the release layer can be applied to the outer surface of the film 13 by dipping, powder coating, or the like. Alternatively, a method can be employed in which the surface of the film 13 is coated with a resin material formed into a tubular shape. Alternatively, a method can be employed in which the outer surface of the film 13 is sandblasted, an adhesive primer layer is then applied to the sandblasted surface of the film 13, and then a release layer is applied over the primer layer.

[0065] (2) Heater

[0066] The heater 11 is an elongated plate-shaped heating element having an effective heating area width W11 ( Figure 7 ) whose temperature suddenly rises over its entire length due to power supply, and the heater has a relatively low heat capacity. In this embodiment, the heater is a ceramic heater. In this heater 11, the heating element (heating resistor, heating resistor layer when power is supplied) is formed by printing a conductive paste made of silver palladium (Ag-Pd) or the like in a thick film (layer) on a thin, elongated plate-like substrate (ceramic substrate) made of AlN (aluminum nitride) with excellent thermal conductivity.

[0067] Then, on the heating element, a glass coating of about 50-60 μm thick is provided integrally with the heating element as a slidable insulating member, thereby constituting a ceramic heater. In this embodiment, the glass coating side is the heater front surface side, and the ceramic heater contacts the inner surface of film 13 on this side.

[0068] The heating element is formed along the longitudinal direction of the substrate, and its length corresponds to the width of the largest width size sheet available in the fixing device or is longer than the above length by a predetermined distance. The length range of the heating element is the effective heating area width W11 of the heater 11. In the heater 11, a chip-shaped thermistor (first thermistor) 18 ( Figure 6 and8 ), the thermistor is sandwiched between itself and the heating element. The thermistor 18 is fixed to the substrate (heater rear surface) with a predetermined pressure by a pressing device (not shown) such as a spring.

[0069] (3) Thermal insulation retaining parts

[0070] The heat insulating holder (heater holding member, hereinafter referred to as the holder) 12 is an elongated member extending in the longitudinal direction (width direction) of the film 13 and is formed of a heat-resistant resin material such as a liquid crystal polymer, a phenolic resin, PPS or PEEK. As the thermal conductivity decreases, the heat consumption of the heater 11 is less, so that the heat can be effectively conducted to the film 13. Therefore, a filler such as glass balls or silica balls can also be included in the resin layer. In a state where the front surface of the heater 11 faces the inner surface of the film 13, the heater 11 is engaged with a groove 12a ( Figure 8 ) and is held by the groove 12a. In addition, the retaining member 12 also has the function of guiding the film 13 to rotate.

[0071] (4) Pressurized support

[0072] The pressure support 14 is a rigid member extending in the longitudinal direction of the film 13 and receiving the reaction force from the pressure roller 20. Ideally, the pressure support 14 is formed of a material that is resistant to bending even under high pressure. In this embodiment, the support 14 is a metal support and is a molded member made of SUS304 with a U-shaped cross-section. The support 14 is positioned on the upper surface of the holder 12 and contacts the holder 12, thereby suppressing bending and twisting of the entire assembly 10.

[0073] (5)Fixed flange

[0074] The membrane 13 is loosely joined (assembled) to the assembly (assembly member) of the heater 11, the holder 12, and the support 14 on the outside. Both end portions 14a ( Figure 8 ) protrude toward the outside of the membrane 13 through openings formed at both ends of the membrane 13, and fixing flanges 15 (L, R) located on one end side and the other end side, respectively, engage with the relevant end portions 14a of the pillars 14. The membrane 13 is positioned between the opposite end control (stop) surfaces (opposing collar seat portions) 15a of the engaged flanges 15 (L, R).

[0075] The flanges 15 (L, R) are regulating (preventing) members for regulating (preventing) the movement of the membrane 13 in the longitudinal direction and the shape of the membrane 13 with respect to the circumferential direction, and are molded products of a heat-resistant resin material (e.g., PPS, liquid crystal polymer, phenolic resin, etc.). Each flange 15 (L, R) includes an end regulating surface 15a, an inner peripheral regulating surface 15b, and a pressure receiving portion (pressure receiving portion) 15c.

[0076] (6) Pressure roller

[0077] The pressure roller 20 as a rotatable member is an elastic roller, which includes a core metal 21 made of SUS, SUM (free-cutting steel of sulfur and sulfur composite material), aluminum, etc., and includes an elastic layer 22 formed on the outside of the core metal 21, such as an elastic solid rubber layer, an elastic sponge rubber layer or an elastic foam rubber layer.

[0078] Here, the elastic solid rubber layer is formed of a heat-resistant rubber such as silicone rubber or fluororubber. Furthermore, the elastic sponge rubber layer is formed by foaming silicone rubber to impart a thermal insulation effect. Furthermore, the elastic foam rubber layer is formed by dispersing hollow fillers (microballoons, etc.) in the silicone rubber layer, thereby providing a hardened product with a gas portion therein, thereby enhancing the thermal insulation effect. On these layers, a release layer such as perfluoroalkoxy resin (PFA) or polytetrafluoroethylene resin (PTFE) may also be formed.

[0079] The pressure roller 20 is supported between side plates 25 (L, R) on one end side and the other end side of an apparatus frame 25 so as to be rotatable by bearings 23 on one end side and the other end side of a core metal 21 .

[0080] The assembly 10 is placed between the side plates 25 (L, R) in parallel with the pressure roller 20 so that the heater 11 side faces the upper side of the pressure roller 20. The flanges 15 (L, R) in the assembly 10 engage with the guide holes 25 a symmetrically formed in the side plates 25 (L, R) so that the pressed portions 15 c thereof are slidable (movable) in the direction toward the pressure roller 20.

[0081] Then, the flanges 15 (L, R) receive a predetermined pressing force at the pressed portion 15c, applied by the pressing arms 26a of the pressing mechanism 26 on one end and the other end, in the direction toward the pressure roller 20. The flanges 15 (L, R), the support 14, the retaining member 12, and the heater 11 of the assembly 10 are collectively pressed in the direction toward the pressure roller 20 by this pressing force. Consequently, a portion of the heater 11 and a portion of the retaining member 12 are pressed toward the pressure roller 20 by the predetermined pressing force, overcoming the elasticity of the membrane 13. As a result, a nip N having a predetermined width relative to the sheet feeding direction Pa is formed between the membrane 13 and the pressure roller 20.

[0082] See also Figure 3 and 4 Pressing mechanisms 26 (L, R) are provided on the outside of the side plates 25 (L, R) at one end and the other end of the frame 25. These pressing mechanisms 26 (L, R) have mirror-symmetrical structures and have the same structure.

[0083] Each pressing mechanism 26 (L, R) includes a pressing lever (arm) 26a and a pressing spring 26b. The lever 26a is mounted on the base of the side plates 25 (L, R) so that it can swing about a shaft 26c. The lever 26a extends from the shaft 26c to the side opposite the shaft 26c, via the upper side of the corresponding pressure receiving portion 15c of the flange 15 (L, R).

[0084] The spring 26b is an elastic member that, by bringing the rod 26a into contact with the associated pressure-receiving portion 15c of the flange 15 (L, R), rotates the rod 26a about the shaft 26c in a pressing (urging) direction. In this embodiment, the spring 26b extends between a free end 26d and a pin 26e embedded in the associated side plate 25 (L, R). Thus, the rod 26a contacts the associated pressure-receiving portion 15c of the flange 15 (L, R) through the tension of the spring 26b, applying a predetermined pressing force to the associated pressure-receiving portion 15c.

[0085] The rod 26a is rotatably supported relative to an associated side plate 25 (L, R), thereby generating a rotational torque around the shaft portion 26c by the tension of the spring 26b, and thereby pressing an associated flange 15 (L, R) in the direction toward the pressure roller 20 by a pressing force.

[0086] (7) Fixing operation

[0087] On the other end side (driving side) of the core metal 21 of the pressure roller 20, a driving gear 27 ( Figure 4 and 8 ) is provided concentrically and integrally with the core metal 21. By the control circuit part 100 ( Figure 9 The driving force of the fixing motor (driving source) M1 driven by the fixing motor driving circuit 111 controlled by the controller 1 is transmitted to the gear 27 via a driving transmission mechanism (not shown). Figure 6 The motor is driven to rotate at a predetermined speed in the counterclockwise direction of the arrow R20 shown in FIG.

[0088] By rotating the pressure roller 20, a rotational torque acts on the film 13 in the nip portion N through the friction between the film 13 and the pressure roller 20. The pressure roller 20 serves as a rotatable member for rotating the film 13. The pressure roller 20 rotates the film 13. As a result, the film 13 is rotated around the assembly of the heater 11, the holder 12, and the support 14. Figure 6 The film 13 rotates clockwise as indicated by arrow R13 while the inner surface of the film 13 slides in close contact with a portion of the heater 11 and a portion of the holder 12 in the nip N. The peripheral speed of the film 13 is substantially equivalent to that of the pressure roller 20.

[0089] The end regulating (stopping) surface 15a of the flange 15 (L, R) regulates the end surface (edge ​​surface) 13a ( Figure 8 ), thereby preventing the membrane 13 from moving in the longitudinal direction (thrust direction) of the membrane 13. The inner peripheral control surface 15b is a guide surface for supporting the inner peripheral surface of the membrane 13 at the end of the membrane 13 from the inside of the membrane 13 and is provided as an arc-shaped protruding edge portion facing the inner surface side of the flange 15 (L, R). A lubricant such as fluorine-containing or silicone-type heat-resistant grease is interposed between the membrane 13 and the heater 11 to suppress frictional resistance to a low level, thereby allowing the membrane 13 to rotate (move) smoothly.

[0090] The control circuit section 100 controls the heater drive circuit section 112, thereby starting to energize the heater 11. Although the energizing path from the heater drive circuit section 112 to the heater 11 is omitted in the figure, the energization is achieved by connecting the heater drive circuit section 112 to the heater 11 and the connector 28 ( Figure 7 ) is electrically connected. By this energization, the effective heating area W11 ( Figure 7 ) suddenly increases in temperature over its entire length.

[0091] The temperature of the heater 11 is detected by the first thermistor 18 provided on the rear surface of the heater 11, whereby the detected temperature information is input to the control circuit portion 100 via the A / D converter 103. Further, the temperature of the inner surface of the film 13 which is rotated while being heated by the heater 11 is detected by the second and third thermistors 19a and 19b ( Figure 7 and 8 ) detection, whereby a plurality of pieces of detected temperature information are input to the control circuit portion 100 via the A / D converter 103.

[0092] The control circuit portion 100 determines and appropriately controls the duty ratio, wave number, etc. of the voltage applied from the heater drive circuit 112 to the heater 11 based on the plurality of pieces of detected temperature information (output) input from the first to third thermistors 18, 19a, and 19b. As a result, the temperature in the nip portion N increases to a predetermined fixing set temperature, and thus temperature control is performed.

[0093] In the above-described state of the fixing device 6, the sheet P on which the unfixed toner image is formed passes through the introduction port 25b ( Figure 6 ) is introduced into the fixing device 6 from the image forming section A1 and is gripped and fed through the nip N. While the sheet P is gripped and fed through the nip N, heat from the heater 11 is applied to the sheet P through the film 13. The unfixed toner image is melted by the heat of the heater 11 and fixed on the sheet P as a fixed image by the heat and pressure applied to the nip N. The sheet P exiting the nip N is then discharged to the outside of the fixing device 6 through the discharge port 25 c of the device frame 25.

[0094] In addition, within the frame 25, a sheet guide member, a sheet sensor, etc. are provided between the introduction port 25b and the clamping portion N, and a sheet guide member, a discharge roller pair, a sheet sensor, etc. are provided between the clamping portion N and the discharge port 25c, but these members are omitted in the drawings.

[0095] Here, in this embodiment, the sheet P is fed to the fixing device 6 on the basis of so-called center (line) feeding. Here, center (line) feeding refers to a method in which, when feeding sheets of different sizes, the sheets are fed in such a manner that the centers (center lines) of the respective sheets coincide with each other with respect to the width direction of the sheets (perpendicular to the feeding direction of the recording material (sheet)). Figure 7 In FIG. 1 , “O” represents a reference line (center reference line, imaginary line) serving as the center line in center (line) feed.

[0096] exist Figure 7 In the figure, "WPmax" is the width of the sheet passage area for the maximum width sheet available in the device. In this embodiment, the width of the maximum width sheet available in the device is 330 mm. "WPmin" is the width of the sheet passage area for the minimum width sheet available in the device. In this embodiment, the width of the minimum width sheet available in the device is 100 mm, that is, the width of a postcard. When feeding the minimum width sheet on a center (line) feed (sheet pass) basis, non-sheet passage areas exist on both sides (one end and the other end) outside WPmin with respect to the width direction.

[0097] The effective heating area width W11 of the heater 11 is set equal to or greater than the sheet passing area width WPmax by a predetermined width. The first thermistor 18 is provided in contact with the rear surface of the heater 11 at a position substantially corresponding to the center reference line O.

[0098] The second thermistor 19 a detects the film temperature in a position downstream of the nip N with respect to the film rotation direction and substantially corresponding to the center reference line O in a manner in contact with the inner surface of the film 13. The third thermistor 19 b detects the film temperature in a position downstream of the nip N with respect to the film rotation direction and substantially corresponding to an inner position of one end portion of the sheet passing area width WPmax in a manner in contact with the inner surface of the film 13.

[0099] That is, the second thermistor 19a detects the temperature of the film portion corresponding to a portion within the sheet passing area width WPmax, which is a sheet passing portion common to any sheet having a large or small (various) size available in the apparatus. When a sheet having a width narrower than the maximum width passes through the nip portion N ( Figure 7 ), the third thermistor 19b detects the temperature of the film portion corresponding to the non-sheet passing portion.

[0100] The second and third thermistors 19a and 19b are supported at the free ends of the elongated spring members 19c and 19d, respectively ( Figure 8 The bases of the spring members 19c and 19d are fixed to the holder 12. That is, the second and third thermistors 19a and 19b are supported by the spring members 19c and 19d, respectively, so as to elastically contact and slide with the inner surface of the membrane 13. Furthermore, the second and third thermistors 19a and 19b are installed so that, in a free state, their free ends protrude from the convex outer portion of the membrane 13 using their spring properties during installation of the membrane 13.

[0101] Furthermore, the support column 14 made of metal is provided with a grounding member 19e ( Figure 8 ), this grounding member contacts the inner surface of membrane 13 near second thermistor 19a to establish grounding for membrane 13. Grounding member 19e is an elongated spring member, with its base electrically conductive with support 14 and its free end sliding along the inner surface of membrane 13 in elastic contact with the inner surface of the membrane. Grounding member 19e is similarly mounted for the second and third thermistors 19a and 19b, so that in a free state, its free end protrudes beyond the convex portion of membrane 13 during installation, utilizing its spring properties.

[0102] (Air blowing cooling mechanism)

[0103] The air blowing cooling mechanism (also referred to as a cooling mechanism) 30 will now be described. The air blowing cooling mechanism 30 is a cooling device that prevents the temperature of the non-sheet-passing portion of the assembly 10 from rising when sheets narrower than the maximum width of the sheet material available in the apparatus continuously pass through the clamping portion N. The air blowing cooling mechanism 30 includes a channel provided with an air blowing port and a fan for blowing air through the channel toward the air blowing port to cool a predetermined area of ​​the film 13, which serves as the rotatable heating member. Furthermore, the air blowing cooling mechanism 30 includes a first baffle member having a first surface for closing the air blowing port in a closed position, and a second baffle member having a second surface for closing the air blowing port in a closed position, which also closes the air blowing port.

[0104] The air blowing cooling mechanism 30 is supported by a supporting member (not shown) on the upper side of the upper surface plate (plate) 25U of the frame 25 and is arranged in a predetermined manner close to the upper surface plate 25U. The air blowing cooling mechanism 30 has an inlet port surface on its upper side and an air blowing port surface on its lower side, and the air blowing port surface of the air blowing cooling mechanism 30 is arranged in a predetermined manner opposite to and close to the upper surface of the upper surface plate 25U.

[0105] Figure 10 Viewed from the inlet (air intake) port side Figure 3 Exploded perspective view of the air blowing cooling mechanism 30. Figure 11 Viewed from the upward blowing port side Figure 3 FIG. 1 is a perspective view of an inverted air blowing cooling mechanism 30 , wherein a shutter mechanism 34 (L, R) described later is in a shutter member closed state. Figure 12 yes Figure 11 Exploded perspective view of the air blowing cooling mechanism 30. Figure 13 1 and 2 are perspective views showing only the shutter mechanism 34 (L, R) as viewed from the inside of the shutter mechanism 34 (L, R).

[0106] Figure 14 is a perspective view showing the air blowing cooling mechanism portion, which is Figure 11 The air blowing cooling mechanism 30 is obtained by removing a portion of the baffle members 36L, 37L, 36R, and 37R, wherein the air blowing cooling mechanism portion is viewed from the air blowing port side.

[0107] like Figure 5 As shown, the upper surface plate 25U is provided with two elongated windows 38 (L, R), which extend in the left and right directions, respectively, on the left and right half sides, for allowing cooling air to act on the non-sheet passing portion of the assembly 10 through the air blowing cooling mechanism 30. The two windows 38 (L, R) are arranged symmetrically with respect to the reference line of the center (line) base feed of the sheet P.

[0108] like Figure 7 As shown, each window hole 38 (L, R) is positioned opposite to the upper surface portion of the assembly 10, and when the smallest size sheet available in the apparatus passes through the nip portion N, each window hole 38 (L, R) is positioned to correspond to an associated one of the left non-sheet passing area width WL and the right non-sheet passing area width WR. In this embodiment, the width dimension (length dimension) W38 of each window hole 38 (L, R) is 115 mm (= [(330 mm - 100 mm) / 2].

[0109] The air blowing cooling mechanism 30 includes two elongated channels 32 (L, R) extending in the left-right direction on the left and right sides, respectively. The channels 32 (L, R) include air blowing ports (exhaust ports) 31 (L, R) which correspond to the window holes 38 (L, R) of the upper surface plate 25 on their lower surfaces and extend in the left-right direction ( Figure 12 and 14 ). The upper surface of the channel 32 (L, R) is open and serves as an (air) inlet port surface.

[0110] Two left (side) cooling fans 33 (L1, L2) are arranged in the left-right direction within the left (side) channel 32L to blow cooling air into the left channel 32L. Furthermore, the left channel 32L includes a partition located at a position corresponding to the boundary between the cooling fans 33 (L1, L2) to direct the cooling air from the cooling fans 33 (L1, L2) toward the air blowing port 31L. Furthermore, two right (side) cooling fans 33 (R1, R2) are arranged in the right (side) channel 32R to blow cooling air into the right channel 32R. Similarly, the right channel 32R includes a partition located at a position corresponding to the boundary between the cooling fans 33 (R1, R2).

[0111] Furthermore, the air blowing cooling mechanism 30 includes a damper mechanism 34 serving as an opening and closing mechanism. This damper mechanism is used to open and close not only the air blowing port 31L of the left channel 32L but also the air blowing port 31R of the right channel 32R. This damper mechanism 34 also serves as an opening width adjustment mechanism, adjusting the opening widths of the air blowing ports 31L and 31R. The damper mechanism 34 consists of a left damper mechanism 34L and a right damper mechanism 34R. The left damper mechanism 34L is used to limit the cooling range of the cooling air delivered through the left channel 32L, while the right damper mechanism 34R is used to limit the cooling range of the cooling air delivered through the right channel 32R.

[0112] The left fence mechanism 34L, which includes two fence members, is composed of an inner fence member (first fence member) 36L provided on the longitudinal center (inner) side of the assembly 10, and an outer fence member (second fence member) 37L provided on the longitudinal outer side of the assembly 10. In addition, the left fence mechanism 34L includes a fence pinion 35L rotatably supported by the inner fence member 36L, a drive pinion 41, a rack-like portion (rack teeth) 43L formed in the groove 32L, and a fence motor M2.

[0113] The inner baffle member 36L is arranged on the channel 32L and is slidable in the longitudinal direction of the regulating portion 45L in a state where the guide portion 47L provided on the inner baffle member 36L is engaged with the collar-shaped inner baffle member regulating portion 45L formed along the longitudinal direction of the blowing port 31L.

[0114] The outer baffle member 37L is arranged on the channel 32L and is slidable in the longitudinal direction of the regulating portion 46L in a state where the guide portion 48L provided on the outer baffle member 37L is engaged with the collar-shaped outer baffle member regulating portion 46L formed along the longitudinal direction of the blowing port 31L.

[0115] Further, the outer dam member 37L is engaged with a collar-shaped outer dam member regulating portion 49L formed on the inner dam member 36L with respect to the longitudinal direction of the inner dam member 36L.

[0116] Similarly, the right fence mechanism 34R, which includes two fence members, is composed of an inner fence member (first fence member) 36R provided on the longitudinal center (inner) side of the assembly 10, and an outer fence member (second fence member) 37R provided on the longitudinal outer side of the assembly 10. Further, the right fence mechanism 34R includes a fence pinion 35R rotatably supported by the inner fence member 36R, a drive pinion 41, a rack-like portion (rack teeth) 43R formed in the groove 32R, and a fence motor M2.

[0117] The inner baffle member 36R is disposed on the channel 32R and is slidable in the longitudinal direction of the regulating portion 45R in a state where the guide portion 47R provided on the inner baffle member 36R is engaged with the collar-shaped inner baffle member regulating portion 45R formed along the longitudinal direction of the blowing port 31R.

[0118] The outer baffle member 37R is arranged on the groove 32R and is slidable in the longitudinal direction of the regulating portion 46R in a state where the guide portion 48R provided on the outer baffle member 37R is engaged with the collar-shaped outer baffle member regulating portion 46R formed along the longitudinal direction of the blowing port 31R.

[0119] Further, the outer dam member 37R is engaged with a collar-shaped outer dam member regulating portion 49R formed on the inner dam member 36R with respect to the longitudinal direction of the inner dam member 36R.

[0120] The drive pinion 41 and the flap motor 42 are common components of the left and right flap mechanisms 34 (L, R). The flap motor (drive motor) 42, which serves as the drive source for the drive pinion 41 of the flap mechanisms 34 (L, R), is located near the center between the left and right channels 32L and 32R. The inner flap members 36 (L, R) are provided with rack-like portions 42 (L, R), each of which meshes with the drive pinion 41.

[0121] Rack-like portions 43 (L, R) provided on the left and right channels 32 (L, R) are provided so as to engage with the barrier pinions 35 (L, R) rotatably supported by the barrier members 36 (L, R).

[0122] The drive pinion 41 is driven to rotate in both the forward and reverse directions by the output gear MG of the flapper motor (pulse motor) M2. In conjunction with the forward and reverse rotational drive of this gear 41, the inner and outer flapper members 36 (L, R) and 37 (L, R) of the left and right flapper mechanisms 34 (L, R) move as described above to open and close the air blowing ports 31 (L, R) of the left and right channels 32 (L, R). In other words, in this embodiment, the drive pinion 41 is a drive member for transmitting the drive (driving force) of the flapper motor M2 (output gear MG), which serves as the drive source, to the inner and outer flapper members 36 (L, R) and 37 (L, R) of the left and right flapper mechanisms 34 (L, R).

[0123] The inner and outer baffle members 36 (L, R) and 37 (L, R) of the left and right baffle mechanisms 34 (L, R) are controlled to move to positions corresponding to the width of the sheet P passing through the clamping portion N. Therefore, the widths of the air blowing ports 31 (L, R) of the left and right channels 32 (L, R) (i.e., the widths of the left and right window holes 38 (L, R) in the upper surface plate 25U) are adjusted to the optimal opening width corresponding to the width of the sheet passing therethrough, thereby performing air blowing cooling within a range in which a temperature rise occurs in the non-sheet passing region of the assembly 10.

[0124] The opening and closing operation of the shutter member will be described. The outer shutter member 37R of the right shutter mechanism 34R is provided with a plurality of sensor marks 39 ( Figure 3 and 10The sensor marks 39 are determined corresponding to sheets having various width sizes. Furthermore, first and second photoelectric sensors 40A and 40B for detecting the edge portions of the sensor marks 39 are provided so as to be fixed to the right channel 32R. The edge portion detection information of each sensor mark 39 detected by the first and second photoelectric sensors 40A and 40B is input to the control circuit section 100 via the A / D converter 300, as shown in FIG. Figure 9 shown.

[0125] In this embodiment, the sensor mark 39 and the first and second photosensors 40A and 40B are detection means for detecting the position of the opening (portion) of the shutter member. The control circuit portion 100 causes the shutter motor drive circuit 400 to control the shutter motor M2 so that the second photosensor 40B detects the edge portion of the sensor mark 39 corresponding to the width dimension information of the sheet material P being used, which is input from the external host device 200. In other words, the shutter motor M2 is controlled to rotate in the forward direction (CW (clockwise)) or the reverse direction (CCW (counterclockwise)), thereby driving the left and right shutter mechanisms 34L and 34R.

[0126] Then, when the edge portion of the sensor mark 39 corresponding to the width dimension information of the sheet P to be used and passed through the nip portion N is detected, the fence motor M2 is driven for several milliseconds starting from this time and then stops. As a result, the outer edge portions of the outer fence members 37 (L, R) of the left and right fence mechanisms 34 (L, R) move to positions corresponding to the width of the sheet P to be used and passed through the nip portion N.

[0127] The operation of the left and right cooling fans 33 (L1, L2, R1, R2) in the fixing device 6 in this embodiment will be described. During image formation, when a sheet having a width smaller than the maximum width of a sheet P that can be used in the fixing device 6 and pass through the fixing device 6 is continuously fixed by the fixing device 6, the temperature in the non-sheet passing region increases. The third thermistor 19b detects the inner surface temperature of the film portion corresponding to the non-sheet passing region.

[0128] When the third thermistor 19b detects a temperature not lower than a predetermined threshold temperature, the control circuit portion 100 controls the shutter motor control circuit 400 ( Figure 9 That is, the flapper motor M2 moves the inner and outer flapper members 36 (L, R) and 37 (L, R) of the left and right flapper mechanisms 34 (L, R) to positions corresponding to the width of the small-width sheets that continuously pass through the fixing device 6. In addition, the control circuit portion 100 controls the cooling fan drive circuit 500 ( Figure 9 ), so that the cooling fans 33 (L1, L2, R1, R2) in the left and right channels 32 (L, R) start to operate.

[0129] Therefore, the non-sheet-passing portion of the assembly 10 is cooled by the cooling air from the cooling fan, thereby suppressing a rise in the temperature of the non-sheet-passing region of the fixing device 6 .

[0130] Then, when the temperature detected by the third thermistor 19b is lower than the predetermined threshold temperature, the operation of the cooling fan 33 (L1, L2, R1, R2) is stopped. The temperature range of the ON-OFF control of the cooling fan depending on the temperature detected by the third thermistor 19b is controlled to change according to the operating state of the cooling fan.

[0131] When, for example, B4-size sheets (short-edge feed; 257 mm×364 mm) continuously pass through the fixing device 6 , the temperature range of the ON-OFF control of the cooling fans 33 ( L1 , L2 , R1 , R2 ) in this embodiment is controlled as follows.

[0132] That is, during the passage of the sheet, when the temperature detected by the third thermistor 19b reaches 200°C (the operation start temperature), the operation of the cooling fan 33 (L1, L2, R1, R2) is started. Then, the non-sheet-passing portion of the assembly 10 is cooled by the cooling air, and when the temperature detected by the third thermistor 19b drops to 190°C (the operation stop temperature), the operation of the cooling fan is stopped.

[0133] (Structure of shutter member opening and closing operation)

[0134] Next, the characteristic feature of this embodiment, the shutter member opening and closing operation, will be described in detail using Figures 1 and 15 to 19. The shutter member opening and closing operations of the left shutter mechanism 34L and the right shutter mechanism 34R are similar. However, the operating directions of the left and right shutter mechanisms 34 (L, R) are opposite to each other. Below, the shutter member opening and closing operation of the right shutter mechanism 34R will be described in detail as a representative example.

[0135] First, the opening operation of the shutter member will be described.

[0136] Parts (a) and (b) of FIG. 15 are schematic diagrams of the shutter mechanism 34R in the fully closed state and during the opening movement operation, respectively, as viewed from the inlet port side (the inside of the shutter mechanism 34R).

[0137] Parts (a) and (b) of FIG. 16 are schematic diagrams of the shutter mechanism 34R in a fully closed state and during an opening movement operation, respectively, as viewed from the air blow port side (outside of the shutter mechanism 34R).

[0138] Figure 1736R, the outer dam member 37R, and the channel 32R.

[0139] Part (a) of Figure 15 and part (a) of Figure 16 show the fully closed state of the shutter members of the shutter mechanism 34R. In this state, the blowing port 31R of the channel 32R is closed over the entire width by the inner shutter member 36R and the outer shutter member 37R moved to the fully closed position (closed position).

[0140] That is, the air blowing port 31R and the window hole 38R opposite to the air blowing port 31R are kept in a non-connected state across the entire width. When the cooling fan is not required for cooling (for example, when an image is being fixed on a sheet of the maximum width), the shutter mechanism 34R is in the fully closed position to prevent the cooling fans 33 (L1, L2, R1, R2) from malfunctioning (failure) due to radiant heat from the film 13.

[0141] In this embodiment, the air blowing port 31R is fully closed at the fully closed position. However, a state in which a slight opening is formed may be used as the closed position. In other words, the state in which the air blowing port 31R is fully closed within the range in which the inner baffle member 36R and the outer baffle member 37R can be moved by the control circuit portion 100 is defined as the closed position.

[0142] In this fully closed state of the damper member, the damper motor M2 is rotationally driven in the CW direction (clockwise direction) (the direction of arrow D in Figures 15 and 16). The drive pinion 41, which is meshed with the output gear MG of the damper motor M2, then rotates in the direction of arrow E (clockwise direction in Figure 15). The rack-shaped portion 42R, which is meshed with the drive pinion 41 and formed in the inner damper member 36R, then receives the force generated by the rotation of the drive pinion 41.

[0143] like Figure 17 As shown, the guide portion 47R formed on the inner baffle member 36R engages with the collar-shaped inner baffle member regulating portion 45R formed on the channel 32R along the longitudinal direction of the assembly 10. As a result, the inner baffle member 36R moves in the direction of arrow F toward the center side of the assembly 10 with respect to the longitudinal direction, as shown in parts (b) of Figures 15 and 16.

[0144] The inner fence member 36R includes a support portion 361R that rotatably supports the fence pinion 35R, and the support portion 361R also moves together with the inner fence member 36 as the inner fence member 36 moves in the longitudinal direction of the assembly 10. The fence pinion 35R rotatably supported by the support portion 361R of the inner fence member 36R meshes with a rack-like portion 43R formed on the groove 32R.

[0145] The rack-like portion 43R is fixed to the channel 32R, and therefore does not move even when the inner fence member 36R moves in the longitudinal direction of the assembly 10. Therefore, the inner fence member 36R moves in the longitudinal direction of the assembly 10, causing the fence pinion 35R to rotate in the direction of arrow G (counterclockwise in FIG. 15 ), as shown in FIG. Then, the rack-like portion 44R of the outer fence member 37R meshes with the fence pinion 35R.

[0146] Therefore, when the fence pinion 35R rotates while moving together with the inner fence member 36R, the rack-shaped portion 44R receives, via the fence pinion 35R, a force for moving the rack-shaped portion 44R in the longitudinal direction of the assembly 10. As a result, in association with the movement of the inner fence member 36R in the longitudinal direction (F direction), the outer fence member 37R also moves in the same direction (H direction).

[0147] The guide portion 48R formed on the outer dam member 37R engages with the collar-shaped outer dam member control portion 46R formed on the channel 32 with respect to the longitudinal direction of the assembly 10. Furthermore, the outer dam member 37R engages with the collar-shaped outer dam member control portion 49R formed on the inner dam member 36R with respect to the longitudinal direction of the assembly 10. Therefore, in addition to the movement of the inner dam member 36R, the outer dam member 37R also moves in the direction toward the longitudinal center of the assembly 10 (the direction of arrow H) by a certain amount, that is, twice the movement of the inner dam member 36R, due to the rotation of the dam pinion 35R.

[0148] Here, the width of the air blowing port 31R not covered by the outer and inner dam members 37R and 36R with respect to the longitudinal direction of the fixing film 13 is referred to as the opening width.

[0149] Furthermore, when the outer baffle member 37R is in the closed position (the fully closed position in this embodiment), the surface of the outer baffle member 37R covering the air blowing port 31R is referred to as surface α, and when the inner baffle member 36R is in the closed position (the fully closed position in this embodiment), the surface of the inner baffle member 36R covering the air blowing port 31R is referred to as surface β. At this time, the relationship between the opening width, the outer baffle member 37R, and the inner baffle member 36R is as follows.

[0150] When the opening width is a first width, the outer and inner dam members 37R and 36R include an overlapping region. As shown in FIG. 16(b) , when viewing these dam members 37R and 36R from the fixing film side, a portion of surface α and a portion of surface β overlap. Furthermore, when the opening width is a second width greater than the first width, the overlapping region between the outer and inner dam members 37R and 36R increases further. Therefore, when viewing the dam members 37R and 36R from the fixing film side, as shown in FIG. 16(b) , a portion of surface α and a portion of surface β overlap, and the overlapping region therebetween is greater than when viewing the dam members 37R and 36R from the fixing film side.

[0151] In other words, the inner baffle member 36R has a first surface for closing the air blowing port 31R at the closed position, which closes the air blowing port 31R. The outer baffle member 37R has a second surface for closing the air blowing port 31R at the closed position, which closes the air blowing port 31R. Each of the inner baffle member 36R and the outer baffle member 37R is movable to a closed position, a first open position for changing the opening width of the air blowing port 31R to a first width, and a second open position for changing the opening width of the air blowing port 31R to a second width larger than the first width.

[0152] Further, the shutter members 36R and 37R move so that the overlapping area between the first surface and the second surface when the shutter members 36R and 37R are in the first open position is larger than the overlapping area between the first surface and the second surface when the shutter members 36R and 37R are in the second open position.

[0153] By the opening movement operation of the inner and outer baffle members 36R and 37R as described above, the blow port 31R of the channel 32 gradually opens from the longitudinal end side toward the longitudinal center side. The blow port 31R and the window hole 38R communicate with each other corresponding to the opening width.

[0154] When the inner and outer baffle members 36R and 37R are in the fully closed position, the majority of the guide portion 48R of the outer baffle member 37R is controlled by the collar-shaped outer baffle member control portion 46R. As the opening amount of the air blowing port 31R increases due to the opening movement of the inner and outer baffle members 36R and 37R, the portion of the guide portion 48R formed on the outer baffle member 37R that is controlled by the outer baffle member control portion 46R formed on the channel 32R gradually shortens. Furthermore, the portion of the guide portion 48R that is controlled by the collar-shaped outer baffle member control portion 49R formed on the inner baffle member 36R along the longitudinal direction of the assembly 10 gradually lengthens.

[0155] Next, the closing operation of the shutter member will be described. The closing operation of the shutter member is opposite to the opening operation of the shutter member described above. The details of the closing operation of the shutter member will be described.

[0156] Figure 18 Schematic diagram of the shutter mechanism viewed from the inlet port side (inside the shutter mechanism 34R), wherein the shutter member is in an open position substantially intermediate between the fully closed position and the fully open position. Figure 19 3 is a schematic diagram of the shutter mechanism 34R viewed from the air blowing port side (outside of the shutter mechanism 34R), in which the shutter member is in an open position substantially intermediate between the fully closed position and the fully open position, similar to Figure 18 .

[0157] exist Figure 18 and 19 In this open state of the shutter member shown, the shutter motor M2 is rotationally driven in the CCW direction (counterclockwise direction) (the direction of arrow J). Then, the drive pinion 41 meshing with the output gear MG of the shutter motor M2 rotates in the direction of arrow K. Then, the rack-shaped portion 42R, which is meshed with the drive pinion 41 and formed in the inner shutter member 36R, receives the force generated by the rotation of the drive pinion 41.

[0158] The guide portion 47R formed on the inner baffle member 36R engages with the collar-shaped inner baffle member regulating portion 45R formed on the channel 32R in the longitudinal direction of the assembly 10. Therefore, the inner baffle member 36R moves in the direction of arrow L toward the outside of the assembly 10 with respect to the longitudinal direction.

[0159] The support portion 361R of the inner baffle member 36R also moves due to the movement of the inner baffle member 36 in the longitudinal direction of the assembly 10. The baffle pinion 35R, which is rotatably supported by the support portion 361R of the inner baffle member 36R, meshes with the rack-like portion 43R formed on the groove 32R. The rack-like portion 43R is fixed to the groove 32R, so that it does not move even when the inner baffle member 36R moves in the longitudinal direction of the assembly 10. Therefore, the inner baffle member 36R moves in the longitudinal direction of the assembly 10, causing the baffle pinion 35R to rotate in the direction of arrow M ( Figure 18 (clockwise in the direction of rotation).

[0160] Then, the rack-shaped portion 44R of the outer fence member 37R meshes with the fence pinion 35R. Therefore, when the fence pinion 35R rotates, the rack-shaped portion 44R receives a force for moving the rack-shaped portion 44R in the longitudinal direction (L direction) of the assembly 10 via the fence pinion 35R. As a result, in conjunction with the movement of the inner fence member 36R in the longitudinal direction, the outer fence member 36R also moves in the same direction (N direction).

[0161] The guide portion 48R formed on the outer baffle member 37R engages with the collar-shaped outer baffle member regulating portion 46R formed on the channel 32 with respect to the longitudinal direction of the assembly 10. In addition, the outer baffle member 37R engages with the collar-shaped outer baffle regulating portion 49R formed on the inner baffle member 36R with respect to the longitudinal direction of the assembly 10.

[0162] Therefore, in addition to the amount of movement of the inner dam member 36R, the outer dam member 37R is also moved by the rotation of the dam pinion 35R in the direction of the arrow N toward the longitudinal outside of the assembly 10 by a certain amount, that is, twice the amount of movement of the inner dam member 36R. As a result, the outer dam member 37R and the inner dam member 36R are closed so that the overlapping area therebetween is reduced.

[0163] By the closing movement of the inner and outer baffle members 36R and 37R, the blow port 31R of the channel 32 is gradually closed from the longitudinal center side toward the longitudinal end side. The blow port 31R and the window hole 38R communicate with each other corresponding to the gradually decreasing opening width.

[0164] When the inner and outer baffle members 36R and 37R are in the fully open position, the guide portion 48R of the outer baffle member 37R is fully controlled by the collar-shaped outer baffle member control portion 49R formed on the inner baffle member 36R along the longitudinal direction of the assembly 10. As the opening amount of the air blowing port 31R decreases due to the closing movement of the inner and outer baffle members 36R and 37R, the portion of the guide portion 48R formed on the outer baffle member 37R controlled by the outer baffle member control portion 49R formed on the inner baffle member 36R gradually shortens. In addition, the portion of the guide portion 48R controlled by the outer baffle member control portion 46R formed on the channel 32R along the longitudinal direction of the assembly 10 gradually lengthens.

[0165] In this embodiment, when the shutter members of the left and right shutter mechanisms 34L and 34R are fully closed, as shown in Figure 1(a), the range covered by the shutter mechanisms 34L and 35R reaches a width of 330 mm. When the shutter members are fully closed, as shown in Figure 1(b), the shutter mechanisms 34L and 35R can open their left and right openings, reducing the gap between them to a width of 100 mm. Therefore, even when sheets with a width ranging from 330 mm to 100 mm, the width of a postcard, pass through the fixing device 6, the cooling range can be adjusted by appropriately adjusting the positions of the shutter members.

[0166] Therefore, in this embodiment, the air-blowing cooling mechanism 30 employs a configuration in which multiple flap members of the left and right flap mechanisms 34 (L, R), which are movable according to the width of the sheets being used, move while overlapping each other during their opening and closing operations. Consequently, as the flap members open, their cooling control area decreases, thereby expanding the maximum opening width of the flap members and, consequently, the controlled width of the fixing member ends within the cooling range of the cooling fan. Consequently, even when small-sized sheets such as postcards and envelopes pass through the fixing device 6, sheet passage can be achieved without compromising productivity.

[0167] <Example 2>

[0168] Parts (a) and (b) of Figure 20 are schematic diagrams of the main part of the air blowing cooling mechanism in Embodiment 2. Also in this embodiment, similarly to Embodiment 1, the sheet P is fed to the fixing device 6 based on the so-called center (line) feeding using the center (line) of the sheet width. Therefore, similarly to Embodiment 1, Figure 14 The channel 32 is provided with an air blowing port 31L at one end and an air blowing port 31R at the other end relative to the longitudinal direction thereof. Furthermore, a baffle member is provided for changing the opening width of each of the air blowing ports 31 (L, R) according to the lateral length of the sheet P introduced into the fixing device 6.

[0169] In this embodiment, the baffle members on one end side and the other end side are respectively composed of a single baffle member 90L and a single baffle member 90R (a one-side single baffle structure). Part (a) of Figure 20 shows a state in which the baffle members 90 (L, R) are moved to the fully closed position by a moving mechanism (not shown) and the air blowing ports 31 (L, R) are fully closed by the baffle members 90 (L, R).

[0170] Part (b) of Figure 20 shows a state where the shutter member 90 (L, R) located at the fully closed position is moved to the fully open position at the longitudinal center portion of the channel 32 by a moving mechanism (not shown) and the air blowing port 31 (L, R) is fully opened.

[0171] In this embodiment, the two baffle members 90 (L, R) on one end and the other end are operated to overlap each other inside and outside as the baffle members are opened. In part (b) of Figure 20, the baffle members 90 (L, R) on the one end and the other end are overlapped in the fully open position at the longitudinal center of the channel 32, so that the baffle member 90L on the one end is arranged on the outside, and the baffle member 90R on the other end is arranged on the inside.

[0172] Therefore, also in the case of the baffle configuration of Example 2, similar to Example 1, the baffle member opening operation can be performed while the baffle member reduces the cooling control range, so that the channel opening width can be expanded by the baffle member.

[0173] <Example 3>

[0174] In Embodiments 1 and 2, the sheet P is fed to the fixing device 6 based on the so-called center feed using the center of the sheet width. That is, the sheet P passes through the fixing device 6 in such a manner that the sheet passing area is based on the longitudinal center position of the assembly 10. Similarly, in the case where the sheet passing area is based on a single end portion, as in Figure 21 As shown (so-called one-side feed basis, in which the sheet is fed based on one of its ends), similarly to embodiments 1 and 2, the non-sheet passing portion of the assembly 10 is raised in temperature.

[0175] In this case as well, by providing the air blowing cooling mechanism 30 similarly to the embodiments 1 and 2, the temperature rise of the non-sheet passing portion can be suppressed. However, unlike the embodiments 1 and 2, Figure 21 As shown, the channel 32A is required on only one side, and therefore, it is sufficient to provide the shutter mechanism 34A on only one side.

[0176] In this embodiment, similarly to the case of the right shutter mechanism 34R described in Embodiment 1, the shutter mechanism 34A is composed of an inner shutter member 36A and an outer shutter member 37A extending in the longitudinal direction of the assembly 10. Therefore, the size of the air blowing cooling mechanism 30 can be made smaller than in the case of performing the shutter member opening operation using a single shutter structure.

[0177] <Example 4>

[0178] In an air-blowing cooling mechanism, when a baffle structure using a single set of left and right baffle members is employed, friction occurs as the baffle members slide on the channels. Therefore, as a reference example, as shown in FIG41 , to reduce friction between the channels 132 and each of the left and right baffle members 134L and 134R, it is considered to provide the left and right baffle members 134L and 134R with ribs C and D, respectively. Thus, baffle members 134 (L, R) slide only on the surfaces of ribs C and D, along with the air-blowing port surface (surface E) and the channel guide surface (surface F) of the channels 132, thereby reducing sliding resistance.

[0179] On the other hand, in the baffle member configuration of the air-blowing cooling mechanism 30 in Examples 1 to 3, inner and outer baffle members are provided to increase the maximum opening width of the baffle members. As the inner and outer baffle members move while overlapping each other, sliding resistance may occur between them. Therefore, it is desirable to reduce sliding resistance not only between the channel and each baffle member, but also between the inner and outer baffle members.

[0180] However, when ribs are provided between the inner and outer baffle members along the baffle member opening and closing direction, gaps are generated between the inner and outer baffle members due to the ribs, so that air may leak through the gaps and cool the sheet passing area.

[0181] Examples 4 and 5 are examples of countermeasures to prevent air leakage through gaps. When using the air blowing cooling mechanism 30 of Examples 4 and 5, by shaping the inner baffle members as described in the following examples, the contact area between the inner and outer baffle members can be reduced, while simultaneously suppressing air leakage through the gaps between the inner and outer baffle members toward the sheet passage area. Consequently, sliding resistance can be reduced.

[0182] (Structure of inner and outer baffle members)

[0183] The structures of the inner and outer dam members in this embodiment (Embodiment 4) will be described. Figure 13 As shown, in the left and right fence mechanisms 34 (L, R), the inner fence members 36 (L, R) are connected via a drive pinion 41 and a rack (rack-like portion) 42 (L, R). The drive pinion 41 is driven by the fence motor M2 to transmit drive (driving force), thereby moving the inner fence members 36 (L, R).

[0184] Furthermore, the inner baffle members 36 (L, R) are respectively provided with baffle pinions 35 (L, R). These baffle pinions 35 (L, R) are meshed and connected with the racks 44 (L, R) of the outer baffle members 37 (L, R) and the fixed racks 43 (L, R) of the channels 32 (L, R).

[0185] When the inner dam members 36 (L, R) move, the dam pinions 35 (L, R) rotate along the fixed racks 43 (L, R) of the channels 32 (L, R). A configuration is employed in which the racks 44 (L, R) of the outer dam members 37 (L, R) are pushed in the same direction as the direction of movement of the inner dam members 36 (L, R) by the rotation of the dam pinions 35 (L, R).

[0186] Therefore, the outer baffle members 37 (L, R) can move along the blowing ports 31 (L, R) of the channels 32 (L, R) by an amount twice as large as the amount of movement of the inner baffle members 36 (L, R). With this configuration, the outer baffle members 37 (L, R) can move to the outer sides of the blowing ports compared to the inner baffle members 36 (L, R).

[0187] Figure 22 1 shows the state of the inner baffle member 36 (L, R) viewed from the blowing port side of the channel (inner baffle member outer surface view), Figure 23 The state of the outer baffle member 37 (L, R) viewed from the inlet port side of the channel (outer baffle member inner surface view) is shown.

[0188] During opening and closing of the baffle members, the rear sides of the surfaces 50 of the inner baffle members 36 (L, R) and the surfaces 52 of the outer baffle members 37 (L, R) move while sliding against each other. Figure 22 As shown, the area 51 of the inner baffle member 36 (L, R) opposite to the rear side of the surface 52 of the outer baffle member 37 (L, R) is formed in a concave shape relative to the area 60, thereby being separated from the rear side of the surface 52 of the outer baffle member 37 (L, R).

[0189] In this embodiment, the thickness of region 51 of the inner baffle member 36 (L, R) is thinner than the thickness of surface 50 and region 60 on the channel air blowing port side. Therefore, the contact area between region 51 and the rear side of surface 52 of the outer baffle member 37 (L, R) is reduced, thereby reducing sliding friction. Meanwhile, surface 50 and region 60 slide together with the rear side of surface 52 of the outer baffle member 37 (L, R).

[0190] Here, the contact portion (region) 60 may preferably be provided continuously so as to be perpendicular to the direction ( Figure 22 When the contact portion 60 is discontinuous in a direction perpendicular to the opening and closing direction of the inner baffle members 36 (L, R), air from the cooling fans 33 (L1, L2, R1, R2) may leak toward the sheet passing area.

[0191] Further, in the closed position, the contact portion 60 may preferably be provided in an area where the contact portion 60 overlaps with the outer baffle members 37 (L, R), respectively. Figure 22As shown in FIG. 1 , the contact portion 60 may be preferably provided at the outer end portion of the inner dam member 36 (L, R) relative to the longitudinal direction of the film. This is because the contact portion 60 can always contact the outer dam member 37 (L, R) by the opening and closing operation of the inner dam member 36 (L, R) and the outer dam member 37 (L, R).

[0192] Furthermore, not only the contact portion 60 but also the surface 50 is provided as a slidable surface in a direction parallel to the opening and closing direction of the inner and outer dam members 36(L, R). Therefore, during the opening and closing operation, it is possible to suppress the region 51 from sliding together with the outer dam member 37(L, R) due to the inclination of the inner and outer dam members 36(L, R).

[0193] Here, the height of the contact portion 60 and the surface 50 from the region 51 is 0.5 mm or more.

[0194] <Example 5>

[0195] Figures 24 to 26 This is a diagram showing the structure of Example 5.

[0196] Figure 24 1 shows the state of the inner baffle member 36 (L, R) viewed from the blowing port side of the channel (inner baffle member outer surface view), Figure 25 The state of the outer baffle member 37 (L, R) viewed from the inlet port side of the channel (outer baffle member inner surface view) is shown.

[0197] In Example 4, Figure 22 As shown, the thickness of the region 60 provided at the end of the inner dam member 36 (L, R) away from the drive pinion 41 is not reduced. That is, in Example 4, an uneven portion for reducing sliding resistance may not be provided between the region 51 and the region 60 of each inner dam member 36 (L, R).

[0198] In this embodiment, Figure 25 As shown, ribs 53 are provided on surfaces 52 (sliding surfaces) of the outer dam members 37 (L, R) at ends 70 on the drive pinion 41 side. The thickness of the ribs 53 may preferably be equal to the difference in thickness between the surfaces 50 and 51 of each inner dam member 36 (L, R). Here, the height of the ribs 53 from the surfaces 52 is 0.5 mm or more.

[0199] Here, the ribs 53 may preferably be provided continuously so as to extend in a direction perpendicular to the opening and closing direction of the outer baffle members 37 (L, R). Figure 24When the operating portion 60 is discontinuous in a direction perpendicular to the opening and closing direction of the outer baffle members 37 (L, R), air from the cooling fans 33 (L1, L2, R1, R2) may leak toward the sheet passing area.

[0200] Further, in the closed position, the ribs 53 may be preferably provided in the areas where the contact portions 60 overlap with the inner baffle members 36 (L, R), respectively. Figure 25 As shown, it is preferable to provide the ribs 53 at the inner ends of the outer baffle members 37 (L, R) with respect to the longitudinal direction of the membrane. This is because the ribs 53 can always contact the inner baffle members 36 (L, R) by the opening and closing operations of the inner baffle members 36 (L, R) and the outer baffle members 37 (L, R).

[0201] That is, in a case where the mechanism performs an opening and closing operation while a plurality of baffle members (in this embodiment, two baffle members of each of the outer baffle member and the inner baffle member) slide against each other, at least one baffle member has a surface that becomes thinner from the sliding surface on the sliding surface side. The other baffle member opposite to the baffle member has a surface that becomes thicker from the sliding surface on the sliding surface side.

[0202] In the case of the fourth embodiment, the thickness of the end portion 60 of the inner baffle member 36 (L, R) away from the driving pinion 41 is kept thick, thereby filling the gap between the inner baffle member 36L and the outer baffle member 37L and the gap between the inner baffle member 36R and the outer baffle member 37R. Therefore, the air from the cooling fan 33 (L1, L2, R1, R2) is prevented from leaking through the gap between the inner baffle member 36 (L, R) and the outer baffle member 37 (L, R). In other words, the air is prevented from leaking along the gap between the inner baffle member 36 (L, R) and the outer baffle member 37 (L, R). Figure 25 The direction of the arrow S shown causes leakage from the fan to blow air to the non-sheet passing area as well as the sheet passing area of ​​the assembly 10, thereby preventing the temperature from decreasing.

[0203] In the case of Example 5, the thickness of the end portion 60 of the inner baffle member 36 (L, R) away from the drive pinion 41 is thin, and the rib 53 is provided at the end portion 70 on the drive pinion 41 side. By adopting this configuration, the gap between the inner baffle member 36L and the outer baffle member 37L and the gap between the inner baffle member 36R and the outer baffle member 37R are filled. Therefore, the air from the cooling fan 33 (L1, L2, R1, R2) is prevented from passing through the above gaps along the Figure 26 The air leaks in the direction of the arrow S shown, and is prevented from being blown onto the non-sheet passing area and the sheet passing area of ​​the assembly 10, thereby preventing the temperature from decreasing.

[0204] <Example 6>

[0205] In the air blowing cooling mechanism 30, if the positions of the racks 42 (L, R) of the left and right baffle members are offset relative to the drive pinion 41, the opening widths of the channel air blowing ports 31 (L, R) may differ between the left and right baffle members. For example, a situation may arise where one baffle member fully closes the opening while the other baffle member does not. Therefore, it is necessary to assemble the racks 42 (L, R) and the drive pinion 41 so that their phases are aligned with the drive pinion 41.

[0206] Therefore, as a reference example, we will consider Figure 42 The structure shown. The assembly of the left and right fence members 134L and 134R in a single-flap structure having a single left and a single right fence member will be described. The marking 420L provided on the rack 142L of the left fence member 134L and the marking 420R provided on the rack 142R of the right fence member 134R are visually aligned with the markings 410a and 410b provided on the drive pinion 41, respectively (i.e., the positions of the tips (vertices) of the opposing "△" markings are aligned with each other on opposite sides).

[0207] However, in the air blowing cooling mechanism 30 in which a plurality of baffle members are provided on each of the left and right sides to increase the maximum opening width of the baffle members as in the first embodiment, the following situation occurs. That is, when the phase of the innermost baffle member is deviated, the deviation amount of the outer baffle member following the innermost baffle member becomes greater than Figure 42 Furthermore, for the plurality of baffle members on each side, when each phase of the baffle members deviates, gaps may be generated between the baffle members or the baffle members may not be able to completely close the opening.

[0208] Therefore, when the number of baffle members increases, not only the number of positions where phase alignment is required increases, but also the accuracy required. However, when phase alignment is performed by visual observation (such as Figure 42 ), there is a problem that the operability is poor and therefore the opening cannot be completely closed.

[0209] Example 6 (this embodiment) is a construction embodiment of a countermeasure to the above-mentioned problem. In the case of adopting a baffle mechanism construction or a baffle mechanism assembling method as in this embodiment, even in a construction in which a plurality of baffle members are provided on each of the left and right sides, when the left and right baffle members are assembled by aligning their phases with each other, compared to Figure 42According to the configuration (method) of the reference example, operability can be further improved. Furthermore, the shutter mechanism can be assembled while performing phase alignment with high precision.

[0210] (Assembly of a baffle structure having two baffle members on each side)

[0211] The structure and assembly method of the air blowing cooling mechanism 30 in Example 6 will be described. The air blowing cooling mechanism 30 in this embodiment includes left and right baffle mechanisms 34 (L, R) provided with two inner baffle members 36 (L, R) and two outer baffle members 37 (L, R) (a structure with two baffle members on each side). Therefore, it is necessary to align the phases of the four baffle members during assembly to allow them to move to predetermined positions in a bilaterally symmetrical manner relative to the air blowing ports 31 (L, R) of the channels 32 (L, R).

[0212] To facilitate phase alignment during assembly, a jig 101 for baffle assembly, shown in FIG. 27(a), is used. The jig 101 is composed of a base jig 101a and a central jig 101b. As shown in FIG. 27(b), the base jig 101a has a slot 105 at its longitudinal center. The central jig 101b engages with the slot 105 and is thereby removably mounted on the base jig 101a (i.e., it can be attached to and removed from the base jig 101a).

[0213] Four pins 102 (a, b, c, d) are provided on the upper surface (front surface) of the central clamp 101b. As will be described later, the pin 102a is used to align the inner and outer fence members 36L and 37L of the left fence mechanism 34L. As will be described later, the pin 102b is used to align the inner and outer fence members 36R and 37R of the right fence mechanism 34R. The pins 102c and 102d are used to align the rack 42L, drive pinion 41, and groove 32L of the inner fence member 36L, and the rack 42R, drive pinion 41, and groove 32R of the inner fence member 36R, respectively.

[0214] As shown in part (b) of Figure 27, two bosses 103 (a, b) are provided on the surface of the slot portion 105 of the base fixture 101a. Part (c) of Figure 27 is a schematic diagram of the central fixture 101b as viewed from the lower surface side (rear surface side). On the lower surface side of the central fixture 101b, two holes 104 (a, b) corresponding to the bosses 103 (a, b) are provided. When the central fixture 101b is installed in the slot portion 105 of the base fixture 101a, the bosses 103a and the holes 104a engage with each other accordingly, and the bosses 103b and the holes 104b engage with each other accordingly. Therefore, the central fixture 101b is installed in the slot portion 105 in a state that prevents displacement.

[0215] During assembly, as shown in FIG. 28( a ), the inner fence member 36L of the left fence mechanism 34L is engaged within the outer fence member 37L. In this state, the outer fence member regulating portion 49L of the inner fence member 36L slides along the guide member 48L of the outer fence member 37L. Thus, the two fence members 36L and 37L are assembled in a stacked state.

[0216] Furthermore, as shown in FIG. 28( b ), the inner fence member 36R of the right fence mechanism 34R is engaged within the outer fence member 37R. In this state, the outer fence member control portion 49R of the inner fence member 36R slides along the guide member 48R of the outer fence member 37R. Thus, the two fence members 36R and 37R are assembled in a stacked state.

[0217] Referring to the inner baffle members 36 (L, R) and the outer baffle members 37 (L, R) assembled in a stacked state as described above, the inlet port surface side (the baffle member inner surface side) is the upper side, and the air blowing port surface side (the baffle member outer surface side) is the lower side. Further, the assembled left and right members are arranged in a cross state so that Figure 29 As shown, the rack 42L of the inner baffle member 36L is located further up than the inlet port surface side of the inner baffle member 36R, while the rack 42R of the inner baffle member 36R is located further up than the inlet port surface side of the inner baffle member 36L.

[0218] At this time, the positioning hole 352L of the inner dam member 36L and the positioning hole 351L of the outer dam member 37L are substantially concentrically positioned with each other. Further, the positioning hole 352R of the inner dam member 36R and the positioning hole 351R of the outer dam member 37R are substantially concentrically positioned with each other.

[0219] In this state, if Figure 30 As shown, the left and right baffle mechanisms 34L and 34R are mounted on the center jig 101b of the jig 101, wherein the center jig 101b is mounted on the base jig 101a. The mounting method at this time is as follows.

[0220] 1) The pin 102a of the jig 101 is penetrated from bottom to top through the positioning hole 351L of the outer dam member 37L and the positioning hole 352L of the inner dam member 36L.

[0221] 2) The pin 102b of the jig 101 is penetrated from bottom to top through the positioning hole 351R of the outer dam member 37R and the positioning hole 352R of the inner dam member 36R.

[0222] 3) The pin 102c of the jig 101 is penetrated from below to above the positioning hole 353L of the rack 42L for the inner dam member 36L.

[0223] 4) The pin 102d of the jig 101 is penetrated from below to above the positioning hole 353R of the rack 42R for the inner dam member 36R.

[0224] Then, if Figure 31 As shown, the fence pinions 35L and 35R are mounted on fence pinion shafts 354L and 354R of the inner fence members 36L and 36R, respectively.

[0225] The fence pinions 35 (L, R) are respectively meshed with and connected to the racks 42 (L, R) of the outer fence members 37 (L, R). Then, when the inner fence members 36 (L, R) move, the racks 44 (L, R) of the outer fence members 37 (L, R) are pushed in the same direction as the moving direction of the inner fence members 36 (L, R).

[0226] Therefore, the outer baffle members 37 (L, R) can move along the blowing ports 31 (L, R) of the channels 32 (L, R) by twice the amount of movement of the inner baffle members 36 (L, R).

[0227] With this configuration, the outer baffle members 37 (L, R) are moved to the outside of the inner baffle members 36 (L, R) above the air blowing ports 31 (L, R) of the channels 32 (L, R). In other words, the opening width of the air blowing ports 31 (L, R) of the channels 32 (L, R) can be adjusted throughout the entire length of the channels 32 (L, R) by using the two baffle members on the left and the two baffle members on the right.

[0228] Furthermore, if Figure 13 As shown, a driving pinion 41 is installed. Figure 32 As shown, the drive pinion 41 is a stepped gear including a gear 411 meshing with the output gear GM of the fence motor M2, a gear 412 meshing with the rack 42 (L, R) of the inner fence member 36 (L, R), and a center hole 413. Furthermore, the drive pinion 41 is provided with holes 414 (a, b) for respectively allowing the pins 102c and 102d of the center clamp 101b to be inserted.

[0229] When installing the driving pinion 41, the position of the driving pinion 41 is adjusted so that the pins 102c and 102d of the center clamp 101b enter the holes 414c and 414d, and the gear 412 is installed toward the center clamp 101b side. In addition, each of the pins 102c and 102d can be inserted into either of the holes 414a and 414b.

[0230] Then, the channels 32 (L, R) are installed. Figure 33 The surface of the channel 32 (L, R) on the air blowing port side (channel lower surface) is shown. As described above with reference to FIG. 1 and other aspects in Example 1, the channel 32 (L, R) is provided with the air blowing port 31 (L, R), through which air for cooling the assembly 10 passes. Furthermore, the channel 32 (L, R) is provided with an inner baffle member control portion 45L for the inner baffle member 36L, an inner baffle member control portion 45R for the inner baffle member 36R, an outer baffle member control portion 46L for the outer baffle member 37L, and an outer baffle member control portion 46R for the outer baffle member 37R.

[0231] Furthermore, if Figure 33 As shown, the channel 32 (L, R) includes a rack 43L meshing with the flapper pinion 35L, a rack 43R meshing with the flapper pinion 35R, and a drive pinion shaft 80. Furthermore, near the drive pinion shaft 80, holes 81 (a, b) are provided for allowing the pins 102c and 102d of the clamp 101 to be inserted.

[0232] Then, Figure 33 The groove 32 is opposite to the clamp 101 including the central clamp 101b, so that the driving pinion shaft 80 faces the Figure 34 In the illustrated fixture 101, the left and right baffle mechanisms 34 (L, R) are mounted on the central fixture 101b using the procedure and method described in Figures 28 to 32. The relative orientation of the channel 32 and the fixture 101 is then adjusted to connect the racks 43 (L, R) to the baffle pinions 35 (L, R).

[0233] Then, the channel 32 is mounted on the fixture 101 while positioning the components so that the pins 102 c and 102 d of the center fixture 101 enter the holes 81 a and 81 b of the channel 32 respectively, thereby driving the pinion shaft 80 into the center hole 413 of the drive pinion 41 . Figure 35 The state where the channel 32 is mounted on the jig 101 is shown.

[0234] Therefore, after the channel 32 is mounted on the fixture 101, as shown in FIG. Figure 36As shown, the central jig 101 b is detached from the base jig 101 a together with the inner fence member 36 , the outer fence member 37 , the drive pinion 41 and the channel 32 .

[0235] Then, these components are held so that the inner and outer dam members 36, 37, and the drive pinion 41 are sandwiched between the central jig 101b and the channel 32 to prevent the inner and outer dam members 36, 37, and the drive pinion 41 from falling out of the channel 32, and these components are turned upside down. The resulting structure is placed on the base jig 101a so that the central jig 101b and the base jig 101a are positioned on opposite sides relative to the remaining components.

[0236] Then, if Figure 38 As shown, only the center clamp 101 b is removed from the inner fence member 36 , outer fence member 37 , drive pinion 41 and channel 32 by disengaging the pins 102 ( a , b , c , d ) from the channel 32 .

[0237] Then, if Figure 39 As shown, outer baffle members 37(L, R) slide in the direction of arrow Q, closing air ports 31(L, R) of channels 32(L, R). As a result, inner baffle members 36L and 36R move relative to each other, increasing the distance between them. At this point, the distance between inner baffle members 36(L, R) increases to a distance greater than the distance between which baffle member movement control (limiting) member 82, described later, enters the inner baffle members 36(L, R).

[0238] Then, if Figure 40 As shown, a baffle member movement control member 82 is mounted on the drive pinion 41 and secured to the drive pinion shaft 80 of the channel 32 via a fastening member such as a screw. The baffle member movement control member 82 functions to prevent the drive pinion 41 from disengaging from the channel 32. Furthermore, the baffle member movement control member 82 limits the movable areas of the inner baffle members 36 (L, R) and the outer baffle members 37 (L, R). By limiting these areas, the baffle member movement control member 82 prevents the inner baffle members 36 (L, R) and the outer baffle members 37 (L, R) from disengaging from the channel 32 (L, R).

[0239] When the inner and outer baffle members 36(L, R) and 37(L, R) are removed, the baffle member movement regulating member 82 is removed, and then the outer baffle member 37(L, R) is slid to a position inside the position of the fixing member (baffle member movement regulating member) 82. As a result, the inner and outer baffle members 36(L, R) also slide in association with the outer baffle members 37(L, R), so that the guide members 47(L, R) of the inner and outer baffle members 36(L, R) are disengaged from the inner and outer baffle member regulating portions 45(L, R) of the channels 32(L, R), thereby allowing the inner and outer baffle members 36(L, R) and 37(L, R) to be removed.

[0240] The above-described configuration and assembly method of the air blowing cooling mechanism 30 are summarized as follows.

[0241] (1) The air blowing cooling mechanism 30 is used in the fixing device 6, which includes the fixing member 10 for heating the image on the recording material. The air blowing cooling mechanism 30 includes a channel 32 including an air blowing port 31 for cooling a set area of ​​the fixing member 10, a baffle member for changing the opening width of the air blowing port 31 according to the lateral length of the recording material P introduced into the fixing device 6, and a driving member 41 for transmitting drive (driving force) to the baffle member.

[0242] The baffle member is composed of a plurality of baffle members 36 and 37 and has a configuration in which an area of ​​the baffle member surface for changing the opening width of the air blowing port of the baffle member is reduced by movement of the plurality of baffle members as the baffle member opens.

[0243] The channel 32 , the plurality of baffle members 36 and 37 and the driving member 41 are provided with positioning holes 81 , 351 , 352 , 353 and 414 at predetermined positions for aligning the phases of the plurality of baffle members 36 and 37 and the driving member 41 during assembly of the air blowing cooling mechanism 30 .

[0244] (2) In the assembly method of the air blowing cooling mechanism 30 described in (1) above, the plurality of pins 102 are provided at predetermined positions, and a jig 101 is used for positively positioning the channel 32, the plurality of baffle members 36 and 37, and the drive member 41. The channel 32, the plurality of baffle members 36 and 37, and the drive member 41 are positioned by engaging their positioning holes with the associated pins 102, thereby performing phase alignment of the plurality of baffle members 36 and 37 and the drive member 41.

[0245] As described above, in the method for assembling the air blowing cooling mechanism 30, the air blowing cooling mechanism 30 is assembled using the assembly jig 101 while simultaneously aligning the phases of the inner baffle members 36 (L, R) and the outer baffle members 37 (L, R) with the drive pinion 41. Therefore, the phase alignment of the baffle members can be performed more simply than in the method of the reference example shown in FIG.

[0246] <Other embodiments>

[0247] (1) The embodiments of the present invention have been described above. However, the numerical values ​​of dimensions, conditions, etc. mentioned in the above embodiments are examples, and therefore, the present invention is not limited thereto. These numerical values ​​can be appropriately selected within the scope of the application of the present invention. For example, roller fixing type and IH fixing type fixing devices can also be used in combination with the air blowing cooling mechanism of the above embodiments.

[0248] (2) The plurality of baffle members may be three or more baffle members.

[0249] Furthermore, a bellows-type member (foldable member) that can be expanded and folded can also be used as the baffle member. The surface area of ​​these bellows-type baffle members for changing the opening width of the air blowing port 31 of the baffle member also decreases as the baffle member is opened.

[0250] (3) The film 13 in the film heating type fixing device 6 described in the above embodiment is not limited to a film having a configuration in which the inner surface of the film 13 is supported by the heater 11 and the heat insulating holder 12, and the film 13 is driven by the pressure roller 20. For example, the film 13 may also be a unit type in which the film 13 is stretched and extended around a plurality of rollers and is driven by any one of these rollers.

[0251] (4) The pressing member 20 that cooperates with the film 13 to form the nip N is not limited to a roller member. For example, a pressure belt unit (also a fixing member) including a belt stretched and extended around a plurality of rollers may be used.

[0252] (5) As the fixing device 6, the device for fixing the unfixed colorant image formed on the sheet by heating the colorant image t is described as an example, but the present invention is not limited to this. For example, a device for increasing the gloss (glossiness) of the image by heating and re-fixing the colorant image temporarily fixed on the recording paper can also be used (in this case, the device is also called a fixing device). That is, for example, the fixing device 6 can also be a device for fixing the partially fixed colorant image on the sheet or a device for subjecting the fixed image to a heating treatment. Therefore, the fixing device 6 can also be, for example, a surface heating device (equipment) for adjusting the gloss or surface properties of the image.

[0253] (6) The imaging device described using the printer A as an example is not limited to an imaging device for forming monochrome images, but may also be an imaging device for forming color images. Furthermore, by adding necessary devices, equipment, and housing structures, the imaging device can be implemented in various applications, such as a copier, a facsimile machine, and a multifunction machine having the functions of these machines.

[0254] (7) In the above description, for the sake of convenience, the processing of the recording material (sheet) P is described using terms related to paper (sheets) (e.g., sheet (paper) passing, sheet feeding, sheet discharge, sheet passing portion, and non-sheet passing portion, etc.), but the recording material is not limited to paper. The recording material P is a sheet-like recording medium (medium) on which a toner image can be formed by an image forming apparatus. For example, regular or irregular recording media such as plain paper, thin paper, thick paper, high-quality paper, coated paper, envelopes, postcards, seals, resin sheets, overhead projector (OHP) sheets, printing sheets, formatted paper, etc. can be listed.

[0255] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications and equivalent structures and functions.

Claims

1. An image heating device, comprising: a first rotatable member and a second rotatable member configured to form a nip in which a toner image is fixed to a recording material; Blowing mechanism; a channel provided on one end side of the first rotatable member in the longitudinal direction of the first rotatable member and configured to guide air from the air blowing mechanism toward one end portion of the first rotatable member with respect to the longitudinal direction of the first rotatable member; as well as an opening and closing mechanism configured to open and close the blowing port of the channel, wherein the opening and closing mechanism includes a first baffle member and a second baffle member, the first baffle member and the second baffle member being movably provided on the one end side of the first rotatable member in the longitudinal direction of the first rotatable member and cooperatively closing the blowing port of the channel, wherein the first baffle member and the second baffle member are movable to a closed position, a first open state, and a second open state, wherein the closed position is a state in which the air blowing port of the channel is closed, and in the closed position, the first baffle member is located on the center side in the longitudinal direction relative to the second baffle member, wherein in the first open state, the blowing port of the channel is open, and the opening width of the blowing port of the channel is a first width, In the first open state, the first shutter member is located in a first position and the second shutter member is located in a second position, the first position being a position located on the center side in the longitudinal direction relative to the position of the first shutter member in the closed position, and the second position being a position located on the center side in the longitudinal direction relative to the position of the second shutter member in the closed position. In the first open state, the first shutter member is located on the center side in the longitudinal direction relative to the second shutter member, and In the first open state, at least a portion of the first baffle member and the second baffle member overlap each other, and wherein in the second open state, the opening width of the blowing port of the channel is a second width greater than the first width, In the second open state, the first shutter member is located at a third position, and the second shutter member is located at a fourth position, the third position being a position located on the center side in the longitudinal direction relative to the first position, and the fourth position being a position located on the center side in the longitudinal direction relative to the second position. In the second open state, the first shutter member is located on the center side in the longitudinal direction relative to the second shutter member, and In the second open state, an overlapping area between the first baffle member and the second baffle member is larger than that in the first open state.

2. The image heating device according to claim 1, wherein The opening and closing mechanism includes a first gear and a second gear. The first baffle member includes a first rack portion meshing with the first gear and a rotation shaft of the second gear, The channel includes a second rack portion meshing with a second gear, and When the first gear rotates, the first baffle member and the second baffle member are movable along the longitudinal direction.

3. The image heating apparatus according to claim 1, wherein When the air blow port of the channel is open, the opening and closing mechanism moves the second shutter member to be in a positional relationship in which the second shutter member is closer to the first rotatable member than the first shutter member. 4 . The image heating apparatus according to claim 1 , further comprising a common driving motor configured to move the first and second shutter members to open and close the air blowing port of the channel.

5. The image heating apparatus according to claim 1, wherein The air blowing port of the channel includes a first fan and a second fan, the first fan is located on a central portion side of the first rotatable member in a longitudinal direction of the first rotatable member and the second fan is located on the one end side of the first rotatable member in the longitudinal direction of the first rotatable member.

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