JP5493797B2 - Image forming apparatus and fixing device - Google Patents

Description

  The present invention relates to an image forming apparatus and a fixing device.

2. Description of the Related Art As a fixing device used in an image forming apparatus such as a copying machine or a printer, a fixing device including a heating member configured by a belt member (fixing belt) stretched by a plurality of rolls is known.
For example, Patent Document 1 includes a fixing belt stretched between a fixing roller and a heating roller, and a pressure roller that contacts the outer peripheral surface of the fixing belt and forms a nip with the fixing belt. Fixing provided with a fixing member having a shape with a large curvature at the exit separation surface inside the fixing belt at a position corresponding to the exit separation portion of the nip formed by the fixing roller and the pressure roller via the belt An apparatus is described.

Japanese Patent Laid-Open No. 2003-5565

Here, for maintenance and inspection of the image forming apparatus, there is a case where a plurality of unit parts such as a fixing unit incorporated in the image forming apparatus are pulled out from the image forming apparatus main body. When such a unit portion is relatively heavy, if the plurality of unit portions are pulled out, the image forming apparatus main body may be inclined with respect to the floor surface.
SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus and a fixing device that can avoid a state in which a plurality of unit portions are pulled out from an image forming apparatus main body.

According to a first aspect of the present invention, there is provided a main body portion of an image forming apparatus that forms an image on a recording material, a heating member that is arranged so as to be drawable with respect to the main body portion, and that heats the recording material, and the heating member. A pressure member that forms a nip portion between the heating member and the heating member, and a fixing unit that fixes the image formed on the recording material; A cooling unit disposed on the downstream side of the recording material conveyance path of the fixing unit and cooling the image fixed on the recording material, and the fixing unit with respect to the main body unit. An image forming apparatus including: a pull-out exclusive unit that prevents the cooling unit from being pulled out in a pulled-out state and prevents the fixing unit from being pulled out in a state where the cooling unit is pulled out .
According to a second aspect of the present invention, the drawer exclusive means includes a locking member having a locking position for locking with the main body portion and a non-locking position for not locking with the main body portion. A gripping portion disposed to be movable with respect to the main body so as to switch between the locking position and the non-locking position, and the locking member of the gripping portion from the locking position to the non-locking engaging the moving plate to be engaged with said cooling unit to move relative to the body part with to switch to the position, relative to the engaging movement plate relative to the cooling unit along with the said fixing portion is pulled out The image forming apparatus according to claim 1, further comprising a restriction plate that restricts movement.
According to a third aspect of the present invention, the pull-out exclusive means separates the engagement moving plate from the cooling portion when the locking member of the grip portion moves from the non-locking position to the locking position. The image forming apparatus according to claim 2, wherein the image forming apparatus is moved in a moving direction.
According to a fourth aspect of the invention, the extraction exclusion means comprises a biasing member to which the limiting plate urges the restriction plate in a direction to limit the relative movement of the engaging movement plate, fixed to the fixing portion It is, that the restriction plate against the biasing force of the biasing member is further comprising constituting a holding portion for holding the restriction plate in a position which does not restrict the relative movement of the engaging movement plate The image forming apparatus according to claim 2, wherein the image forming apparatus is an image forming apparatus.

Invention of claim 5, a fixing member, the fixing member is disposed so as to press the fixing device having a pressure member to form a nip portion where the recording material passes between the fixing member The cooling device located on the downstream side of the recording material conveyance path of the fixing device main body is pulled out with respect to the main body and the image forming apparatus main body that houses the fixing device main body so that it can be pulled out. And a pull-out exclusion means for blocking and pulling out the fixing device main body in a state where the cooling device is pulled out.
According to a sixth aspect of the present invention, the drawer exclusive means includes a locking member having a locking position for locking with the image forming apparatus main body and a non-locking position for locking with the image forming apparatus main body. A gripping portion disposed movably with respect to the image forming apparatus main body so as to switch between the locking position and the non-locking position of the locking member; and the locking member of the gripping portion is locked An engagement moving plate that moves with respect to the image forming apparatus main body and engages with the cooling apparatus as the position is switched from the position to the non-locking position, and the cooling as the fixing apparatus main body is pulled out. it is the fixing device according to claim 5, characterized in that is configured to include a, a limit plate for limiting the relative movement of the engaging mobile plate with respect to the apparatus.
According to a seventh aspect of the present invention, the pull-out exclusive means separates the engagement moving plate from the cooling device when the locking member of the grip portion moves from the non-locking position to the locking position. The fixing device according to claim 6, wherein the fixing device is moved in a moving direction.
The invention described in claim 8, wherein the drawer exclusion means comprises a biasing member to which the limiting plate urges the restriction plate in a direction to limit the relative movement of the engaging moving plate, the fixing device main body fixed, the limiting plates against the biasing force of the biasing member is further comprising constituting a holding portion for holding the restriction plate in a position which does not restrict the relative movement of the engaging movement plate The fixing device according to claim 6, wherein the fixing device is a fixing device.

According to the first aspect, it is possible to avoid a state in which the plurality of unit portions are pulled out from the image forming apparatus main body.
According to claim 2, it is possible to easily configure the drawer exclusion means as compared with the case where the present invention is not adopted.
According to claim 3, the engagement moving plate can be forcibly moved as compared with the case where the present invention is not adopted.
According to the fourth aspect, the drawer exclusion means can be easily configured as compared with the case where the present invention is not adopted.
According to the fifth aspect, it is possible to avoid a state in which the plurality of unit portions are pulled out from the image forming apparatus main body.
According to the sixth aspect, compared to the case where the present invention is not adopted, the drawer exclusion means can be configured easily.
According to claim 7, the engagement moving plate can be forcibly moved as compared with the case where the present invention is not adopted.
According to the eighth aspect, compared to the case where the present invention is not adopted, the drawer exclusion means can be configured easily.

1 is a diagram illustrating a configuration example of an image forming apparatus to which a fixing device according to an exemplary embodiment is applied. FIG. 3 is a cross-sectional configuration diagram for describing a configuration of a fixing unit of the present embodiment. It is a front view explaining a drawer exclusive mechanism. It is a figure explaining the composition of the handle of a drawer exclusive mechanism. It is a perspective view explaining the structure of a drawer exclusive mechanism more concretely. It is a front view explaining a drawer exclusive mechanism. It is a perspective view explaining the state which the slide plate of a drawer exclusive mechanism is engaging with the cooling unit. It is a fragmentary perspective view of a drawer exclusive mechanism. It is a fragmentary perspective view of a drawer exclusive mechanism. It is a front view explaining a drawer exclusive mechanism. It is a front view explaining a drawer exclusive mechanism. It is a perspective view explaining the state where the slide plate of a drawer exclusive mechanism does not engage with a cooling unit.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
<Description of Image Forming Apparatus>
FIG. 1 is a diagram illustrating a configuration example of an image forming apparatus 1 to which a fixing device (fixing unit) 60 according to the present embodiment is applied. An image forming apparatus 1 shown in FIG. 1 is a so-called “tandem type” color printer, and controls an image forming unit 10 that forms an image based on image data, operation control of the entire image forming apparatus 1, for example, a personal computer (PC). A main control unit 50 that performs communication with the user, image processing performed on image data, and the like, and a user interface (UI) unit 90 that receives operation input from the user and displays various information to the user. ing.

<Description of Image Forming Unit>
The image forming unit 10 is a functional unit that forms an image by, for example, electrophotography, and includes six image forming units 11C, 11M, 11HC, 11HM, 11Y as an example of toner image forming units arranged in parallel. 11K (hereinafter “image forming unit 11”). Each image forming unit 11 functions as a functional member, for example, a photosensitive drum 12 on which an electrostatic latent image is formed and then each color toner image is formed, and the surface of the photosensitive drum 12 is charged with a predetermined potential. A charger 13 that exposes the photosensitive drum 12 charged by the charger 13 based on image data, and development that develops the electrostatic latent image formed on the photosensitive drum 12 with toner of each color. And a cleaner 16 for cleaning the surface of the photosensitive drum 12 after transfer.
Each developing unit 15 of each image forming unit 11 is connected to toner containers 17C, 17M, 17HC, 17HM, 17Y, and 17K (hereinafter referred to as “toner containers 17”) for storing toners of respective colors by toner transport paths (not shown). ing. Each color toner is supplied from the toner container 17 to the developing device 15 by a supply screw (not shown) provided in the toner conveyance path.

  Each of the image forming units 11 is configured in substantially the same manner except for the toner accommodated in the developing device 15, and each of them is C (cyan) color, M (magenta) color, HC (high chroma cyan) color, and HM (high chroma magenta). Color, Y (yellow), and K (black) toner images are formed. The HC color here is a cyan color having a cyan hue, a hue that is brighter and higher in saturation than the C color, and the HM color has a magenta hue, and M color. It is a magenta color with a brighter color tone and a relatively high saturation.

The image forming unit 10 intermediates the intermediate transfer belt 20 to which the respective color toner images formed on the photosensitive drums 12 of the respective image forming units 11 are transferred and the respective color toner images formed by the respective image forming units 11. A primary transfer roll 21 for transferring (primary transfer) to the transfer belt 20. Furthermore, a secondary transfer roll 22 that batch-transfers (secondary transfer) each color toner image transferred onto the intermediate transfer belt 20 onto a sheet that is a recording material (recording paper), and each color toner that has been secondarily transferred. And a fixing unit 60 as an example of a fixing unit (fixing device) for fixing the image on the sheet.
In addition, the image forming unit 10 cools each color toner image fixed on the sheet by the fixing unit 60 and promotes fixing of the color toner image on the sheet, and the sheet is bent (curled). And a curl correction unit 85 for correcting the above. The fixing unit 60 is an example of a first unit part, and the cooling unit 80 is an example of a second unit part. The cooling unit 80 is located downstream of the fixing unit 60 in the paper conveyance path.
In the image forming apparatus 1 of the present embodiment, the intermediate transfer belt 20, the primary transfer roll 21, and the secondary transfer roll 22 constitute a transfer unit. Further, an area where the secondary transfer roll 22 is disposed and each color toner image on the intermediate transfer belt 20 is secondarily transferred to a sheet is hereinafter referred to as a “secondary transfer area Tr”.

<Description of paper transport system>
In addition, the image forming unit 10 feeds out a plurality of (two in the present embodiment) sheet storage containers 40A and 40B that store sheets and a sheet stored in the sheet storage containers 40A and 40B as a sheet transport system. Feeding rolls 41A and 41B, a first transport path R1 for transporting paper from the paper container 40A, and a second transport path R2 for transporting paper from the paper container 40B. Further, the image forming unit 10 includes a third transport path R3 that transports the paper from the paper storage container 40A and the paper storage container 40B toward the secondary transfer region Tr. In addition, the image forming unit 10 conveys the sheet on which the toner image of each color is transferred in the secondary transfer region Tr so as to pass through the fixing unit 60, the cooling unit 80, and the curl correcting unit 85. And a fifth transport path R5 for transporting the sheet from the curl correction unit 85 toward the sheet stacking section 44 provided in the discharge section of the image forming apparatus 1.
From the first conveyance path R1 to the fifth conveyance path R5, conveyance rolls and conveyance belts are arranged along the respective conveyance paths to sequentially convey the fed sheets.

<Description of double-sided conveyance system>
In addition, the image forming unit 10 serves as a double-sided conveyance system in which an intermediate paper storage container 42 that temporarily holds the paper on which the toner images of each color are fixed on the first surface by the fixing unit 60 and the paper from the curl correction unit 85 as intermediate paper. A sixth transport path R6 for transporting toward the storage container 42 and a seventh transport path R7 for transporting the paper stored in the intermediate paper storage container 42 toward the third transport path R3 are provided. Further, the image forming unit 10 is disposed on the downstream side of the curl correction unit 85 in the sheet conveyance direction, and conveys the sheet toward the sheet stacking unit 44 and a sixth conveyance path R5 that conveys the sheet to the intermediate sheet storage container 42. A distribution mechanism unit 43 that selectively distributes the sheet to the path R6 and a feeding roll 45 that feeds the sheet stored in the intermediate sheet storage container 42 toward the seventh transport path R7 are provided.

<Description of image forming operation>
Next, a basic image forming operation in the image forming apparatus 1 according to the present embodiment will be described.
Each of the image forming units 11 of the image forming unit 10 forms toner images of C color, M color, HC color, HM color, Y color, and K color by an electrophotographic process using the above functional members. Each color toner image formed by each image forming unit 11 is primary-transferred sequentially on the intermediate transfer belt 20 by the primary transfer roll 21 to form a composite toner image in which the respective color toners are superimposed. The synthetic toner image on the intermediate transfer belt 20 is conveyed to the secondary transfer region Tr in which the secondary transfer roll 22 is disposed as the intermediate transfer belt 20 moves (in the direction of the arrow).

On the other hand, in the paper transport system, the feeding rolls 41A and 41B rotate in synchronization with the start timing of image formation in each image forming unit 11, and the UI unit 90, for example, out of the paper storage container 40A and the paper storage container 40B. The designated sheet is fed by the feeding rolls 41A and 41B. The sheet fed by the feeding rolls 41A and 41B is transported along the first transport path R1 or the second transport path R2 and the third transport path R3, and reaches the secondary transfer region Tr.
In the secondary transfer region Tr, the composite toner image held on the intermediate transfer belt 20 is secondarily transferred collectively onto the paper by the transfer electric field formed by the secondary transfer roll 22.

Thereafter, the sheet on which the composite toner image is transferred is separated from the intermediate transfer belt 20 and conveyed to the fixing unit 60 along the fourth conveyance path R4. The synthesized toner image on the paper transported to the fixing unit 60 is fixed on the paper after being subjected to a fixing process by the fixing unit 60. Then, the sheet on which the fixed image is formed is cooled by the cooling unit 80, and the curl correction unit 85 corrects the bending of the sheet. Thereafter, the paper passing through the curl correction unit 85 is guided by the distribution mechanism unit 43 to the fifth transport path R5 during single-sided printing and transported toward the paper stacking unit 44.
The toner (primary transfer residual toner) adhering to the photosensitive drum 12 after the primary transfer and the toner (secondary transfer residual toner) adhering to the intermediate transfer belt 20 after the secondary transfer are respectively cleaner 16, And removed by the belt cleaner 26.

On the other hand, during double-sided printing, the paper on which the fixed image is formed on the first surface of the paper by the above-described process passes through the curl correction unit 85 and is then guided to the sixth transport path R6 by the distribution mechanism unit 43. The sixth transport path R6 is transported toward the intermediate paper storage container. Again, the feeding roll 45 rotates in accordance with the start timing of image formation on the second surface by each image forming unit 11, and the sheet is fed out from the intermediate sheet storage container 42. The sheet fed by the feed roll 45 is transported along the seventh transport path R7 and the third transport path R3 and reaches the secondary transfer region Tr.
In the secondary transfer region Tr, as in the case of the first surface, the toner images of the respective colors on the second surface held on the intermediate transfer belt 20 are collectively applied to the sheet by the transfer electric field formed by the secondary transfer roll 22. Second transfer is performed.

Then, the paper on which the toner images are transferred on both sides is fixed by the fixing unit 60 as in the case of the first side, cooled by the cooling unit 80, and further corrected by the curl correction unit 85. Is done. Thereafter, the paper that has passed through the curl correction unit 85 is guided to the fifth transport path R5 by the distribution mechanism unit 43 and transported toward the paper stacking unit 44.
In this way, the image forming process in the image forming apparatus 1 is repeatedly executed for the number of printed sheets.

<Description of fixing unit configuration>
Next, the fixing unit 60 used in the image forming apparatus 1 of the present embodiment will be described.
FIG. 2 is a cross-sectional configuration diagram for explaining the configuration of the fixing unit 60 of the present embodiment. The fixing unit 60 includes a fixing belt module 61 as an example of a heating unit that heats a sheet, and a pressure roll 62 as an example of a pressing member configured to be able to contact and separate from the fixing belt module 61. The part is composed.
The fixing belt module 61 rotates while the fixing belt 610 as an example of a belt member and the fixing belt 610 are stretched, and the fixing belt module 61 and the pressure roll 62 are in pressure contact (contact with each other while being pressed). A fixing roll 611 for heating the fixing belt 610 from the inside at the nip portion N, an internal heating roll 612 as an example of a stretching roll for heating the fixing belt 610 while stretching the fixing belt 610 from the inside, a fixing belt An external heating roll 613 as an example of a stretching roll that heats the fixing belt 610 while stretching the 610 from the outside. The fixing belt module 61 includes a tension roll 614 that stretches the fixing belt 610 between the fixing roll 611 and the internal heating roll 612 (upstream of the nip portion N), and a downstream region in the nip portion N. A peeling pad 64 as an example of a peeling member disposed in the vicinity of the fixing roll 611 and a tension roll 615 for tensioning the fixing belt 610 on the downstream side of the nip portion N are provided.

The fixing belt 610 includes, for example, a base layer formed of a polyimide resin, an elastic layer made of silicone rubber laminated on the surface side (outer peripheral surface side) of the base layer, and a PFA coated on the elastic layer. And a release layer made of (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin). Here, the elastic layer is provided in order to improve the image quality especially for color images. That is, the toner image held on the sheet to be fixed is formed by laminating toners of various colors that are powders. Therefore, in order to supply heat uniformly to the entire toner image at the nip portion N, it is preferable that the surface of the fixing belt 610 be deformed following the unevenness of the toner image on the paper.
The fixing roll 611 is a cylindrical roll formed of, for example, aluminum or SUS, and receives a rotational driving force from a driving motor (not shown) and rotates in the arrow direction in the figure. Then, the fixing roll 611 is heated to a predetermined temperature (for example, 150 ° C.) by, for example, three halogen heaters 71 as heating sources disposed inside the fixing roll 611.

The internal heating roll 612 is a cylindrical roll formed of, for example, aluminum or SUS. The internal heating roll 612 is heated to a predetermined temperature (for example, 190 ° C.) by, for example, four halogen heaters 72 serving as heating sources disposed inside.
The internal heating roll 612 is provided with spring members (not shown) that press the fixing belt 610 from the inside to the outside at both ends, and the tension of the entire fixing belt 610 is set to 15 kgf, for example.
Further, the internal heating roll 612 is provided with a mechanism for controlling the meandering (belt walk) of the fixing belt 610. That is, a belt edge position detection mechanism (not shown) that detects the end position (edge position) of the fixing belt 610 is disposed in the vicinity of the internal heating roll 612. The internal heating roll 612 is provided with a displacement mechanism (not shown) that displaces one end of the internal heating roll 612 in a direction perpendicular to the axial direction of the internal heating roll 612. The displacement mechanism displaces the fixing belt 610 in the axial direction of the internal heating roll 612 by displacing one end of the internal heating roll 612 according to the detection result of the belt edge position detection mechanism. Thereby, the belt walk of the fixing belt 610 is controlled.

The external heating roll 613 is a cylindrical roll formed of, for example, aluminum or SUS. Then, the external heating roll 613 is heated to a predetermined temperature (for example, 190 ° C.) by, for example, three halogen heaters 73 serving as heating sources arranged inside.
As described above, the fixing unit 60 of the present embodiment employs a configuration in which the fixing belt 610 is heated by the fixing roll 611, the internal heating roll 612, and the external heating roll 613.

  The peeling pad 64 is a block member made of a metal such as SUS or a rigid body such as resin and having a substantially arc-shaped cross section. The fixing roll 611 is fixedly disposed over the entire axial direction of the fixing roll 611 at a position near the downstream side of the area where the pressure roll 62 is pressed against the fixing roll 611 via the fixing belt 610 (hereinafter referred to as “roll nip portion N1”). Has been. The peeling pad 64 has a predetermined load (for example, a nip width of 5 mm along the traveling direction of the fixing belt 610) in a predetermined width region (for example, 5 mm along the traveling direction of the fixing belt 610) via the fixing belt 610. For example, it is installed so as to press uniformly at an average of 10 kgf), and a “peeling pad nip portion N2” connected to the roll nip portion N1 is formed.

  Next, the pressure roll 62 is formed by laminating an elastic layer made of silicone rubber and a release layer made of a PFA tube in this order from the substrate side, for example, using a cylindrical roll made of aluminum or SUS as a base. ing. The pressure roll 62 is disposed so as to be in contact with and separated from the fixing belt module 61. When the pressure roll 62 is set so as to contact (pressure contact) while pressing the fixing belt module 61, the fixing roll of the fixing belt module 61 is used. As 611 rotates in the direction of the arrow, it follows the fixing roll 611 and rotates in the direction of the arrow.

<Description of the fixing operation in the fixing unit>
Next, the fixing operation in the fixing unit 60 of the present embodiment will be described.
The sheet on which the composite toner image (unfixed toner image) is electrostatically transferred in the secondary transfer region Tr (see FIG. 1) of the image forming apparatus 1 is fixed along the fourth conveyance path R4 (see FIG. 1). It is conveyed toward the nip portion N (see FIG. 2). The unfixed toner image on the paper surface passing through the nip portion N is fixed to the paper mainly by pressure and heat acting on the roll nip portion N1.

  That is, in the fixing unit 60 of the present embodiment, the heat acting on the roll nip portion N1 is mainly supplied by the fixing belt 610. The fixing belt 610 is supplied with heat supplied from the halogen heater 71 arranged inside the fixing roll 611 via the fixing roll 611 and from the halogen heater 72 arranged inside the internal heating roll 612 via the internal heating roll 612. And the heat supplied from the halogen heater 73 disposed inside the external heating roll 613 through the external heating roll 613. As a result, not only the fixing roll 611 but also the internal heating roll 612 and the external heating roll 613 are replenished with heat energy, so that a sufficient amount of heat is secured at the roll nip portion N1 even if the process speed is high. .

In the fixing unit 60 of the present embodiment, the fixing belt 610 that functions as a direct heating member can be configured to have an extremely small heat capacity. In addition, the fixing belt 610 is configured to come into contact with the fixing roll 611 that is a heat supply member, and the internal heating roll 612 and the external heating roll 613 with a wide lap area (large wrap angle). Therefore, since a sufficient amount of heat is supplied from the fixing roll 611, the internal heating roll 612, and the external heating roll 613 in a short period of one rotation of the fixing belt 610, the fixing belt 610 is returned to the necessary fixing temperature in a short time. It becomes possible. Thereby, a predetermined fixing temperature is maintained in the roll nip portion N1.
As a result, in the fixing unit 60 of the present embodiment, the fixing temperature is maintained substantially constant even when the paper is continuously fed at a high speed. In addition, the phenomenon that the fixing temperature drops at the start of the fixing operation at high speed (so-called “temperature droop phenomenon”) is suppressed. In particular, when fixing to thick paper having a large heat capacity, the maintenance of the fixing temperature and the occurrence of temperature droop are suppressed, and furthermore, the fixing temperature is switched halfway according to the type of paper (both the fixing temperature is increased and decreased). Even if necessary, the fixing belt 610 has a small heat capacity, so that the temperature can be easily switched by adjusting the output of the halogen heater 71, and further, the halogen heater 72 and the halogen heater 73.

  In the fixing unit 60 of the present embodiment, the fixing roll 611 is a hard roll formed of aluminum, SUS, or the like, and the pressure roll 62 is a soft roll that covers an elastic layer. Therefore, in the roll nip portion N1, the fixing roll 611 hardly bends, and the surface of the pressure roll 62 is bent, so that a nip region having a width in the traveling direction of the fixing belt 610 is formed. As described above, in the roll nip portion N1, the fixing roll 611 on the side where the fixing belt 610 is wrapped is hardly deformed. Therefore, the fixing belt 610 passes through the roll nip portion N1 while maintaining the moving speed substantially constant. As a result, the fixing belt 610 is prevented from being wrinkled or distorted at the roll nip portion N1, so that a high-quality fixed image is stably provided.

Subsequently, after passing through the roll nip portion N1, the sheet is conveyed to the peeling pad nip portion N2. The peeling pad nip portion N <b> 2 is configured so that the peeling pad 64 is pressed against the pressure roll 62 and the fixing belt 610 is pressed against the pressure roll 62. Accordingly, the roll nip portion N1 has a curved shape that is convex downward due to the curvature of the fixing roll 611, whereas the peeling pad nip portion N2 has a curved shape that is convex upward due to the curvature of the pressure roll 62. Yes.
Therefore, the traveling direction of the sheet heated and pressed under the curvature of the fixing roll 611 in the roll nip portion N1 is changed to the curvature directed in the opposite direction by the pressure roll 62 in the peeling pad nip portion N2. At that time, a minute micro slip occurs between the toner image on the paper and the surface of the fixing belt 610. As a result, the adhesion between the toner image and the fixing belt 610 is weakened, and a state is formed in which the paper is easily peeled off from the fixing belt 610. As described above, the peeling pad nip portion N2 is also positioned in a preparation process for surely peeling in the final peeling process.

  Since the fixing belt 610 is conveyed so as to be wound around the peeling pad 64 at the exit of the peeling pad nip portion N2, the conveyance direction of the fixing belt 610 changes abruptly there. That is, since the fixing belt 610 moves along the outer surface of the peeling pad 64, the bending of the fixing belt 610 becomes large. Therefore, the paper whose adhesion with the fixing belt 610 is weakened in advance in the peeling pad nip portion N2 is separated from the fixing belt 610 by the stiffness of the paper that the paper itself has.

  The sheet separated from the fixing belt 610 is guided in its traveling direction by a peeling guide plate 69 as an example of a peeling guide member disposed on the downstream side of the peeling pad nip portion N2. The paper guided by the peeling guide plate 69 is then conveyed toward the cooling unit 80 by the paper discharge guide 78 and the paper discharge belt 79, whereby the fixing process in the fixing unit 60 is completed.

Next, a drawer exclusion mechanism 30 as an example of a drawer exclusion unit disposed adjacent to the fixing unit 60 and the cooling unit 80 will be described.
FIG. 3 is a front view illustrating the drawer exclusive mechanism 30. In the state shown in FIG. 3, the cooling unit 80 can be pulled out while the fixing unit 60 cannot be pulled out, as will be described later.
The drawer exclusive mechanism 30 shown in FIG. 3 is a mechanism for allowing only one of the fixing unit 60 and the cooling unit 80 to be pulled out. In other words, the image forming apparatus 1 of the present embodiment is configured such that it is impossible to pull out both the fixing unit 60 and the cooling unit 80 by the action of the pull-out exclusive mechanism 30. That is, the fixing unit 60 and the cooling unit 80 included in the image forming apparatus 1 according to the present embodiment are heavy objects, and the image forming apparatus 1 may be inclined with respect to the floor when both are pulled out. In view of such circumstances, the image forming apparatus 1 of the present embodiment includes a pull-out exclusive mechanism 30 for selectively pulling out either the fixing unit 60 or the cooling unit 80. .
The fixing unit 60 includes a fixing main body 63 as an example of a fixing device main body that holds components for fixing.

The drawer exclusive mechanism 30 includes a handle 100 that is positioned in front of the fixing unit 60 and is rotatably attached to the fixing unit 60, and a fixing plate 200 that is fixed to a frame FL that is an example of an image forming apparatus main body. Yes. The frame FL is an example of a main body portion of the image forming apparatus 1, and the handle 100 is an example of a grip portion.
Further, the pull-out exclusive mechanism 30 includes a slide plate 300 as an example of an engagement moving plate disposed on the fixed plate 200 so as to be slidable with respect to the fixed plate 200 and a fixed plate 200 that is rotatable with respect to the fixed plate 200. And a mounting plate 500 that is fixedly mounted to the fixing unit 60 so as to be engageable with the rotating plate 400.
In other words, the handle 100 and the mounting plate 500 are attached to the fixing unit 60. The fixed plate 200 is attached to the frame FL, and the slide plate 300 and the rotating plate 400 are attached to the frame FL via the fixed plate 200.

FIG. 4 is a diagram illustrating the configuration of the handle 100 of the drawer exclusive mechanism 30. (A) of the figure shows a state where the handle 100 is engaged with the frame FL (locking position of the locking member), and (b) shows a state where the handle 100 is not engaged with the frame FL ( The non-locking position of the locking member) is shown.
As shown in FIG. 4, the handle 100 is gripped by a gripping part 110 that is gripped and rotated when operating, a shaft part 120 connected to the gripping part 110, and fixed to the shaft part 120. Projecting engagement portions 130 and 140 located rearward. In addition, the handle 100 includes a protruding bar 150 as an example of a locking member that is fixed to the shaft portion 120 and is located behind the protruding engaging portions 130 and 140.
The grip portion 110 of the handle 100 rotates around the rotation axis K in the direction perpendicular to the paper surface of FIG. When the grip portion 110 of the handle 100 is rotated with respect to the fixing unit 60, the shaft portion 120, the projecting engagement portions 130 and 140, and the projecting bar 150 are rotated in the same direction.

The shaft portion 120 is disposed so as to extend in the direction perpendicular to the paper surface of FIG. As shown in FIG. 3, the protruding engagement portions 130 and 140 protrude in opposite directions.
As shown in FIG. 4, the protruding rod 150 protrudes in the direction opposite to the gripping part 110. When the fixing unit 60 is housed in the frame FL, the protruding rod 150 can be engaged with the hole FL1 of the frame FL (see FIG. 4A). It cannot be pulled out. Further, by rotating the gripping part 110 around the rotation axis K in the direction of the arrow 101, the protruding rod 150 is removed from the hole FL1 of the frame FL (see FIG. 4B), and the fixing unit 60 is moved by the arrow 102. It becomes possible to pull out in the direction.

FIG. 5 is a perspective view illustrating the configuration of the drawer exclusive mechanism 30 more specifically. In the figure, the configuration of the drawer exclusive mechanism 30 other than the handle 100 and the mounting plate 500 is shown.
As shown in FIG. 5, the fixed plate 200 of the drawer exclusive mechanism 30 holds the slide plate 300 so as to be slidable. That is, the slide plate 300 can slide in the direction of the arrow 301 with respect to the fixed plate 200.
Further, the fixed plate 200 of the drawer exclusive mechanism 30 supports the rotating plate 400 so as to be rotatable. That is, the rotating plate 400 can rotate around the rotation axis L with respect to the fixed plate 200.

Between the fixed plate 200 and the slide plate 300, there is attached a tension coil spring 210 that generates a biasing force in a contraction direction when a load in a direction in which both ends of the hook shape are separated from each other acts. That is, one end of the tension coil spring 210 is attached to the fixed plate 200 and the other end is attached to the slide plate 300 in a state where the tension coil spring 210 is pulled. For this reason, the slide plate 300 is always urged in the direction of the arrow 302 by the action of the tension coil spring 210. When the slide plate 300 is slid in the direction of the arrow 303, it tries to return to the direction of the arrow 302 by the tension coil spring 210.
In addition, a torsion coil spring 220 as an example of an urging member that generates an urging force when receiving a torsional moment is attached between the fixed plate 200 and the rotating plate 400. The rotating plate 400 is always urged in the direction of the arrow 401 by the torsion coil spring 220. More specifically, the rotating plate 400 is arranged around the rotation axis L in the direction of an arrow 401 that is a direction in which the upper side of the rotating plate 400 is separated from the fixed plate 200 and the lower side of the rotating plate 400 is close to the fixed plate 200. It is energized.

  More specifically, the slide plate 300 of the drawer exclusive mechanism 30 is disposed on the upper side, and is disposed on the lower side of the circular member 310 that engages with the handle 100 and the position away from the circular member 310. And an extending piece 320 extending laterally so as to be engaged. The slide plate 300 is disposed between the circular member 310 and the extending piece 320, and is disposed in the vicinity of the circular member 310, the insertion hole 330 formed so as to receive the rotating plate 400, and the handle 100. And a projecting piece 340 projecting upward so as to be engaged. For example, a bearing may be used as the circular member 310.

  Further, the rotary plate 400 of the drawer exclusive mechanism 30 is disposed above the torsion coil spring 220, the engagement piece 410 that engages with the cooling unit 80, and the lower side than the torsion coil spring 220, And an insertion piece 420 to be inserted into the insertion hole 330 of the slide plate 300.

  Here, as to the state of the pull-out exclusive mechanism 30 shown in FIG. Is moving in the direction of Further, the rotating plate 400 rotates in the direction of the arrow 401, and the insertion piece 420 of the rotating plate 400 is inserted into the insertion hole 330 of the slide plate 300. Therefore, in FIG. 5, the slide plate 300 does not move in the direction of the arrow 302 even when the protruding piece 340 of the slide plate 300 and the handle 100 are not engaged.

Returning to FIG. 3, the description will be continued.
When the handle 100 shown in FIG. 3 is rotated in the direction of the arrow 101, the circular member 310 of the slide plate 300 engages with the protruding engagement portion 140 of the handle 100, and then the protruding engagement portion 140 moves the circular member 310 to the arrow. Push in the direction of 303.

  As described above, the attachment plate 500 is attached to the fixing unit 60 and moves together with the fixing unit 60. Such a mounting plate 500 is engaged with the protrusion engaging portion 140 to stop the rotation of the handle 100, and the engaging plate 410 of the rotating plate 400 is engaged with the stopper piece 510 to regulate the posture of the rotating plate 400. And a restricting portion 520 as an example of a holding portion.

Based on the above description, the state of the pull-out exclusive mechanism 30 shown in FIG. 3 will be described. The slide plate 300 is moved and stopped in the direction of the arrow 302 by the urging force of the tension coil spring 210. The rotating plate 400 does not rotate in the direction of the arrow 401 (see FIG. 5) due to the engagement piece 410 and the restricting portion 520 of the mounting plate 500 engaging with each other. For this reason, the insertion piece 420 of the rotating plate 400 is separated from the slide plate 300. The insertion hole 330 of the slide plate 300 is positioned so as to be shifted from the insertion piece 420 of the rotating plate 400.
Further, the handle 100 is engaged with the frame FL (see FIG. 4A). For this reason, the fixing unit 60 cannot be pulled out. On the other hand, the cooling unit 80 is not engaged with the extended piece 320 of the slide plate 300, and thus the cooling unit 80 can be pulled out.

FIG. 6 is a front view illustrating the drawer exclusive mechanism 30, and FIG. 7 is a perspective view illustrating a state in which the slide plate 300 of the drawer exclusive mechanism 30 is engaged with the cooling unit 80. In the state shown in FIG. 6, the fixing unit 60 can be pulled out while the cooling unit 80 cannot be pulled out, as will be described later.
As shown in FIG. 6, when the handle 100 rotates in the direction of the arrow 101, the protruding bar 150 of the handle 100 is not engaged with the frame FL (see FIG. 4B). For this reason, the fixing unit 60 can be pulled out. On the other hand, in the cooling unit 80, the extending piece 320 of the slide plate 300 is engaged with the cooling unit 80, and therefore the cooling unit 80 cannot be pulled out.
Note that the protruding engagement portion 140 of the handle 100 is located between the circular member 310 of the slide plate 300 and the protruding piece 340. In other words, when the handle 100 rotates in the direction of the arrow 101, the projecting engagement portion 140 enters between the circular member 310 and the projecting piece 340 and continues to push the circular member 310 in the direction of the arrow 303.

  More specifically, as shown in FIG. 7, the cooling unit 80 includes an attachment member 81 that is disposed in the lower portion and moves together with the cooling unit 80. The attachment member 81 has a receiving portion 82 that receives the extended piece 320. Therefore, when the slide plate 300 of the pull-out exclusive mechanism 30 moves in the direction of the arrow 303, and thereby the extended piece 320 of the slide plate 300 is received by the receiving portion 82 of the cooling unit 80, the fixing unit is moved in the direction of the arrow 102. It cannot be pulled out.

Next, the operation of the rotating plate 400 of the drawer exclusive mechanism 30 will be described.
8 and 9 are partial perspective views of the drawer exclusive mechanism 30. FIG. In both figures, the handle 100 is rotated in the direction of the arrow 101 (see FIG. 6), and the slide plate 300 is moved in the direction of the arrow 303 (see FIG. 5) by the action of the handle 100. .
As shown in FIG. 8, when the fixing unit 60 is not pulled out (see FIG. 6), the restricting portion 520 of the mounting plate 500 engages with the engaging piece 410 of the rotating plate 400, and the arrow 401 (FIG. 5). (Refer to the direction)).
In this case, the insertion piece 420 of the rotating plate 400 does not enter the insertion hole 330 of the slide plate 300. Therefore, when the handle 100 rotates in the direction opposite to the arrow 101, the slide plate 300 returns to the direction indicated by the arrow 302 (see FIG. 5), and the cooling unit 80 can be pulled out.

  As shown in FIG. 9, when the fixing unit 60 is pulled out, the restricting portion 520 (see FIG. 8) of the mounting plate 500 (see FIG. 8) moves together with the fixing unit 60. In the combined piece 410, the rotating plate 400 rotates in the direction of the arrow 401 (see FIG. 5) by the urging force of the torsion coil spring 220 without engaging with the restricting portion 520. Then, the insertion piece 420 of the rotating plate 400 is inserted into the insertion hole 330 of the slide plate 300. Thus, even when the handle 100 rotates in the direction opposite to the arrow 101, the slide plate 300 (see FIG. 7) does not return in the direction of the arrow 302 (see FIG. 7), and the cooling unit 80 cannot be pulled out.

Next, an operation when the handle 100 of the drawer exclusive mechanism 30 is returned will be described.
FIG. 10 is a front view illustrating the drawer exclusive mechanism 30.
As shown in FIG. 10, when the handle 100 is rotated in the direction of the arrow 103, the protruding engagement portion 140 of the handle 100 comes into contact with the protruding piece 340 of the slide plate 300, and then the slide plate 300 is moved in the direction of the arrow 302. The protruding piece 340 is pushed so as to move to. Thereby, the extended piece 320 of the slide plate 300 comes out of the receiving portion 82 (see FIG. 7) of the mounting member 81 of the cooling unit 80. The extension piece 320 moves in the direction of the arrow 302 by the urging force of the tension coil spring 210 after having come out of the receiving portion 82.
More specifically, when the extended piece 320 of the slide plate 300 bites into the attachment member 81 of the cooling unit 80, the extended piece 320 is received by the receiving portion 82 only by the urging force of the tension coil spring 210 in the direction of the arrow 302. Difficult to get out of. Therefore, in this embodiment, as a countermeasure against such galling, the slide plate 300 is forcibly moved in the direction of the arrow 302 by the projecting engagement portion 140 of the handle 100.

Next, the operation of the pull-out exclusion mechanism 30 when the cooling unit 80 is pulled out will be described.
FIG. 11 is a front view illustrating the drawer exclusive mechanism 30, and FIG. 12 is a perspective view illustrating a state where the slide plate 300 of the drawer exclusive mechanism 30 does not engage with the cooling unit 80. 11 is a drawing corresponding to FIG. 6, and FIG. 12 is a drawing corresponding to FIG.
As shown in FIG. 11, when the handle 100 rotates in the direction of the arrow 101, the protruding engagement portion 140 of the handle 100 engages with the circular member 310 of the slide plate 300, and the slide plate 300 moves in the direction of the arrow 303. Start moving. When the handle 100 further rotates in the direction of the arrow 101, as shown in FIG. 12, since the cooling unit 80 is pulled out in the direction of the arrow 102, the extended piece 320 of the slide plate 300 is attached to the cooling unit 80. It hits the side wall surface of the member 81 and cannot move any further in the direction of the arrow 303. Therefore, the handle 100 cannot be removed from the hole FL1 (see FIG. 4B) of the frame FL, and the fixing unit 60 cannot be pulled out in the direction of the arrow 102.

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 30 ... Drawer exclusion mechanism, 60 ... Fixing unit, 63 ... Fixing main body, 80 ... Cooling unit, 81 ... Mounting member, 82 ... Receiving part, 100 ... Handle, 101, 102, 103, 301, 302 , 303, 401 ... arrows, 130, 140 ... projecting engagement parts, 150 ... projecting rod, 200 ... fixed plate, 210 ... tension coil spring, 220 ... torsion coil spring, 300 ... slide plate, 310 ... circular member, 320 ... Extension piece 330 ... insertion hole 340 ... projection piece 400 ... rotation plate 410 ... engagement piece 420 ... insertion piece 500 ... mounting plate 510 ... stopper portion 520 ... regulation portion FL ... frame FL1 ... Hole, K, L ... Rotating shaft

Claims (8)

A main body of an image forming apparatus for forming an image on a recording material;
A heating member that heats the recording material and a nip portion through which the recording material passes are formed between the heating member and the heating member. A fixing unit including a pressure member, and fixing the image formed on the recording material;
A cooling unit disposed so as to be capable of being pulled out with respect to the main body unit, disposed on the downstream side of the recording material conveyance path of the fixing unit, and cooling the image fixed on the recording material;
A drawing exclusive means for preventing the cooling unit from being pulled out in a state where the fixing unit is pulled out from the main body unit, and preventing the fixing unit from being pulled out in a state where the cooling unit is pulled out ;
An image forming apparatus including: The drawer exclusion means is
A locking member having a locking position for locking with the main body and a non-locking position for locking with the main body, and switching between the locking position and the non-locking position of the locking member A gripping part disposed movably with respect to the main body part;
An engagement moving plate that moves with respect to the main body and engages with the cooling unit as the locking member of the gripper is switched from the locking position to the non-locking position;
A limiting plate that restricts relative movement of the engagement moving plate with respect to the cooling unit as the fixing unit is pulled out;
The image forming apparatus according to claim 1, further comprising: The pull-out exclusive means moves the engagement moving plate in a direction of separating from the cooling portion when the locking member of the gripping portion moves from the non-locking position to the locking position. The image forming apparatus according to claim 2. The drawer exclusion means is
An urging member wherein the limiting plate urges the restriction plate in a direction to limit the relative movement of the engaging movement plate,
Is fixed to the fixing portion, a holding portion for the restriction plate against the biasing force of the biasing member holds the limiting plate in a position that does not restrict the relative movement of the engaging movement plate,
The image forming apparatus according to claim 2, further comprising: A fixing member;
A pressure member which is arranged to press the fixing member and forms a nip portion through which the recording material passes with the fixing member ;
A fixing device body having :
While preventing withdrawal of the cooling device located downstream of the recording material conveying path of the fixing device main body in a state in which the fixing device main body is pulled out to the image forming apparatus body housing can be pulled out of the fixing device main body Drawer exclusive means for preventing the fixing device body from being pulled out in a state where the cooling device is pulled out;
Including a fixing device. The drawer exclusion means is
A locking member having a locking position for locking with the image forming apparatus main body and a non-locking position for locking with the image forming apparatus main body, the locking position of the locking member and the non-locking position; A gripping portion that is movably disposed with respect to the image forming apparatus main body so as to switch between,
An engagement moving plate that moves with respect to the image forming apparatus main body and engages with the cooling device as the locking member of the gripper is switched from the locking position to the non-locking position;
A limiting plate that limits relative movement of the engagement moving plate with respect to the cooling device as the fixing device main body is pulled out;
The fixing device according to claim 5, comprising:. The pulling-exclusion means moves the engagement moving plate in a direction of separating from the cooling device when the locking member of the grip portion moves from the non-locking position to the locking position. The fixing device according to claim 6. The drawer exclusion means is
An urging member wherein the limiting plate urges the restriction plate in a direction to limit the relative movement of the engaging movement plate,
Is fixed to the fixing device main body, and a holding portion for the restriction plate against the biasing force of the biasing member holds the limiting plate in a position that does not restrict the relative movement of the engaging movement plate,
The fixing device according to claim 6, further comprising:

Images