JP4848830B2 - Sheet conveying apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a sheet conveying apparatus that conveys a recording sheet and a printer, a copying machine, a FAX, or a multifunction machine having a plurality of these functions, and particularly fixing an unfixed toner image. The present invention relates to a sheet conveying device disposed on the downstream side of the fixing device and an image forming apparatus including the sheet conveying device.

In a conventional electrophotographic image forming apparatus, an unfixed toner image transferred onto the surface of a recording sheet is heated and fixed by a fixing device, conveyed by a sheet conveying device arranged on the downstream side of the fixing device, and then discharged to a discharge tray. Discharged.
As an image forming apparatus provided with such a sheet conveying apparatus, the following prior art (J01) is known.
(J01) Technology described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2002-3042) Patent Document 1 includes a paper discharge roller disposed on the downstream side of the fixing device and a driven roller pressed against the paper discharge roller. A sheet conveying apparatus is described, and a technique for changing the recording sheet conveying speed according to the type of recording sheet used is described.

JP 2002-3042 A

(Problems of conventional technology)
As shown in the prior art (J01), the sheet conveying device is generally composed of a pair of opposing rolls, and one of the pair of rolls is composed of a rubber roll whose surface is not processed. Often.
When printing images with high glossiness (gloss) such as photographs and solid images, the recording sheet after being heated and fixed by the fixing device is still high in the state where it is conveyed to the downstream sheet conveying device, and the toner Is soft, there is a problem that the portion of the sheet conveying device that is in contact with the roll becomes streaky gloss unevenness.

In order to reduce the gloss unevenness, it is conceivable to reduce the contact pressure (nip pressure) of the roll pair, but there is a problem that the sheet conveying performance is lowered. In particular, when a sheet of paper having a large amount of paper dust or additives attached thereto is transported, the surface of the transport roll becomes slippery and the sheet may not be transported.
Although it is conceivable to adjust the sheet conveying speed as in the technique described in the prior art (J01), it is difficult to improve gloss unevenness even if the speed is adjusted, and the configuration for adjusting the speed is complicated. There is a problem to do.

In view of the above circumstances, the present invention has the following description (O01) as a technical problem.
(O01) Reduce the occurrence of gross unevenness

(Invention)
Next, the present invention that has solved the above problems will be described. In order to facilitate the correspondence between the elements of the present invention and elements of specific examples (examples) of the embodiments described later, Add the code enclosed in parentheses. The reason why the present invention is described in correspondence with the reference numerals of the embodiments described later is to facilitate understanding of the present invention, and not to limit the scope of the present invention to the embodiments.

(First invention)
In order to solve the technical problem, the sheet conveying apparatus of the first invention is:
A sheet conveying member (Rh) disposed downstream in the recording sheet (S) conveyance direction of a fixing device (F) for heating and fixing an unfixed toner image on the surface of the recording sheet (S), Excluding the non-concave portion (82a) disposed on the toner image forming surface side and disposed on the surface at a specific portion in the axial direction and contacting the recording sheet (S ) and the non-concave portion (82a). Concavities and convexities (82b) formed by recesses (42a) formed adjacent to the non-concave portions (82a) in the axial direction and deeper than the thickness of the toner layer on the surface of the recording sheet (S) are integrally formed. A sheet conveying member (Rh) having a provided conveying roll (82) and an opposing roll (47) disposed in opposed contact with the conveying roll (82);
It is provided with.

(Operation of the first invention)
In the sheet conveying apparatus of the first invention having the above-described configuration requirements, the sheet conveying member (Rh) conveys the recording sheet (S) of the fixing device (F) that heat-fixes the unfixed toner image on the surface of the recording sheet (S). It is arranged downstream in the direction. A conveyance roll (82) of the sheet conveyance member (Rh) is disposed on the toner image forming surface side of the recording sheet (S) and is disposed on a surface at a specific portion in the axial direction to contact the recording sheet (S). A non-recessed portion (82a) to be conveyed and an axial portion excluding the non-recessed portion (82a) formed adjacent to the non-recessed portion (82a) and on the surface of the recording sheet (S). constituted by than the thickness deeper depressions (42a) irregularities and (82b), but that provided integrally. The opposing roll (47) is disposed so as to face the transport roll (82).
Therefore, in the sheet conveying apparatus according to the first aspect of the present invention, the non-concave portion (82a) arranged at a specific axial portion formed on the surface of the conveying roll (82) contacts and conveys the recording sheet (S). A dent deeper than the thickness of the toner layer on the surface of the recording sheet (S) is formed adjacent to the non-recessed portion (82a) in the axial direction excluding the non-recessed portion (82a), while ensuring the conveyance force. The unevenness (82b) constituted by 42a) can make the uneven gloss (gross unevenness) inconspicuous and reduce the occurrence of the uneven gloss.
(First Embodiment 1)
The sheet conveying apparatus according to the first aspect of the first invention is the first invention,
The said conveyance roll (82) which has the said non-concavo-convex part (82a) arrange | positioned in the axial direction center part
It is provided with.
(Operation of Form 1 of the First Invention)
In the sheet conveying apparatus according to the first aspect of the present invention having the above-described configuration, the unevenness of gloss (gross unevenness) is made inconspicuous by the unevenness (82b) formed in the axial direction portion excluding the central portion in the axial direction, and the center in the axial direction. The non-recessed portion (82a) of the portion can be reliably conveyed while being in contact with the recording sheet (S).

(Second invention)
In order to solve the technical problem, an image forming apparatus according to a second aspect of the invention includes the sheet conveying apparatus according to any one of the first aspect and the first aspect of the invention.
(Operation of the second invention)
The image forming apparatus according to the second aspect of the present invention having the above-described constituent elements includes the sheet conveying apparatus according to any one of the first aspect and the first aspect of the first aspect of the invention, so that uneven gloss can be reduced.

The above-described present invention has the following effect (E01).
(E01) Generation of gross unevenness can be reduced.

Next, specific examples (examples) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left-right direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X, Y, -Y, The direction indicated by Z and -Z or the indicated side is defined as the front side, the rear side, the right side, the left side, the upper side, the lower side, or the front side, the rear side, the right side, the left side, the upper side, and the lower side, respectively.
In the figure, “•” in “○” means an arrow heading from the back of the page to the front, and “×” in “○” is the front of the page. It means an arrow pointing from the back to the back.

FIG. 1 is an overall explanatory view of an image forming apparatus according to a first embodiment.
FIG. 2 is an explanatory diagram illustrating a state where the cover of the image forming apparatus according to the first exemplary embodiment is opened.
In FIG. 1, a printer U as an image forming apparatus according to the first embodiment of the present invention has a paper feed cassette TR1 in which a recording paper S on which an image is recorded is accommodated in a lower portion, and a discharge tray TRh on the upper surface. Is provided. A user interface UI is provided at the top of the printer U.
1 and 2, the printer U according to the first embodiment includes a printer main body (image forming apparatus main body) U1 and an opening / closing cover U2 that can be opened and closed around a rotation center U2a provided at the lower right end of the printer main body U1. Have. The opening / closing cover U2 includes an open position (see a solid line in FIG. 2) for opening the inside of the printer main body U1 in order to replace the units UY to UK and remove a jammed recording sheet, and a normal time when an image forming operation is performed. It is configured to be movable between the closed position to be held (see the two-dot chain line in FIGS. 1 and 2).

  The printer U includes a controller C constituted by a microcomputer, an IPS (image processing system) whose operation is controlled by the controller C, a laser driving circuit DL, a power supply device E, and the like. The power supply device E applies a bias voltage to charging rollers CRy to CRk, developing rollers G1y to G1k, transfer rollers T1y to T1k, and the like which will be described later.

  The IPS (image processing system) uses print data input from an external client computer or the like as latent images corresponding to four color images of K (black), Y (yellow), M (magenta), and C (cyan). The image data is converted into image data for image formation and output to the laser driving circuit DL at a predetermined timing. The laser drive circuit DL outputs a laser drive signal to the latent image writing device ROS (latent image forming device) according to the input image data of each color. The ROS emits laser beams (image writing light) Ly, Lm, Lc, and Lk for image writing of each color according to a laser drive signal.

FIG. 3 is an explanatory diagram of the detachable unit according to the first embodiment.
In FIG. 1, a toner image forming apparatus (detachable unit) UY that forms toner images of Y (yellow), M (magenta), C (cyan), and K (black) in front of the ROS (+ X direction). , UM, UC, UK are arranged. In FIG. 3, a charging roll CRk as a charger and an electrostatic latent image on the surface of the photosensitive member around the drum-shaped photosensitive member (image holding member) Pk of the K (black) toner image forming apparatus UK are displayed as toner images. A developing unit Gk that develops (visible image), a neutralizing member Jk that neutralizes the surface of the photoreceptor Pk, a photoreceptor cleaner (image carrier cleaner) CLk that removes the developer remaining on the photoreceptor surface, and the like are arranged. .

4 is a cross-sectional view taken along line IV-IV in FIG.
3 and 4, the developing device Gk has a developing container 1 in which a developer is accommodated. The developing container 1 includes a developing roll storage chamber 2 in which a developing roll G1k facing the photosensitive member Pk is supported, a first agitation transport chamber 3 that is adjacent to the left side of the developing roll storage chamber 2 and stores developer. And a second agitating and conveying chamber 4 adjacent to the left side of the first agitating and conveying chamber 3. The first agitation transport chamber 3 and the second agitation transport chamber 4 are partitioned by a partition wall 6, and the developer moves between the first agitation transport chamber 3 and the second agitation transport chamber 4 at both front and rear ends. It is configured to be possible. In the first agitation conveyance chamber 3 and the second agitation conveyance chamber 4, agitation conveyance members 7 and 8 for conveying the developer in opposite directions while agitating the developer are arranged.
The developing container 1 of Example 1 contains a two-component developer containing toner and carrier as the developer.

A cylindrical developer transfer chamber 11 is formed on the left side of the second stirring transfer chamber 4. A developer supply port 11a connected to the second stirring chamber 4 is formed at the front end of the developer transport chamber 11, and a developer inlet 11b is formed at the rear end. In the developer transport chamber 11, a developer supply member 12 that transports the developer in the developer transport chamber 11 toward the developer supply port 11 a is disposed.
A first developer replenishing chamber 16 is formed on the left side of the developer transport chamber 11, and a developer dropping path 17 formed at an end in the front-rear direction is provided above the second developer replenishing chamber 16. A second developer replenishing chamber 18 connected therethrough is arranged. The first developer replenishing chamber 16 includes a first developer conveying member (developer replenishing member) 21 and a second developer conveying member that convey the developer in the second developer replenishing chamber 16 to the developer inflow port 11b. A (developer supply member) 22 is disposed.

The first developer conveying member 21 includes a rotating shaft portion 21a and a conveying film 21b made of a flexible resin film such as PET (polyethylene terephthalate) supported by the rotating shaft portion 21a. The transport film 21b is formed with a cut 21c inclined with respect to the axial direction, and an auxiliary film 23 is attached at a position facing the developer inlet 11b of the transport film 21b. Accordingly, when the first developer conveying member 21 rotates, the developer is conveyed to the developer inlet 11b on the rear side by the conveying film 21b in which the notch 21c is formed, and the developer is developed by the auxiliary film 23. It is transferred to the transfer chamber 11.
The second developer conveying member 22 conveys the developer to the first developer conveying member 21 side. A third developer transport member (developer supply member) 24 and a fourth developer transport member (developer supply member) 26 disposed in the second developer supply chamber 18 are provided in the second developer supply chamber 18. The developer is conveyed to the developer dropping path 17 side.
The developer transport chamber 11, the first developer supply chamber 16, and the second developer supply chamber 18 constitute the developer supply container (11 + 16 + 18) of the first embodiment. The developer supply container (11 + 16 + 18) of Example 1 contains toner as a supply developer.

The photoconductor cleaner CLk is disposed on the right side of the second developer supply chamber 18, and the photoconductor cleaner CLk is contacted with the surface of the photoconductor Pk, and the development scraped off by the cleaning blade 31 is provided. And a recovered developer transport member 33 that transports the developer to the recovered developer storage chamber 32.
The black toner image forming apparatus UK of Example 1 includes a photosensitive member Pk, a charger CRk, a developing device Gk, a charge removing member Jk, a photosensitive member cleaner (image carrier cleaner) CLk, a developer supply container (11 + 16 + 18), and the like. As shown in FIG. 2, the process cartridge UK is configured to be detachable from the printer main body (image forming apparatus main body) U1 with the open / close cover U2 moved to the open position. Yes.
The other color toner image forming apparatuses UY, UM, and UC are configured by process units (detachable units) UY, UM, and UC that can be attached to and detached from the printer main body U1 in the same manner as the black toner image forming apparatus UK. Yes.

  1 and 2, a belt module BM supported by an opening / closing cover U2 is disposed on the right side of the photoreceptors Py to Pk. The belt module BM includes a sheet conveying belt B, a belt support roll (Rd + Rj) including a belt driving roll Rd and a driven roll Rj, and transfer rolls T1y, T1m, T1c arranged to face the respective photoreceptors Py to Pk. , T1k, an image density sensor SN1, a belt cleaner CLb, and a sheet suction roll Rk disposed to face the driven roll Rj. The sheet conveying belt B is rotatably supported by the belt support roll (Rd + Rj).

The recording sheet S in the paper feed tray TR1 disposed below the sheet transport belt B is taken out by the paper feed member Rp and transported to the sheet transport path SH.
The recording sheet S in the sheet conveyance path SH is conveyed by the sheet conveyance roll Ra and is sent to the registration roll Rr. The registration roll Rr conveys the recording sheet S to a sheet suction position Q6 that is a region where the driven roll Rj and the sheet suction roll Rk face each other at a predetermined timing. The recording sheet S conveyed to the sheet adsorption position Q6 is electrostatically adsorbed to the sheet conveyance belt B.
When paper is fed from the manual feed tray TR0, the recording sheet S fed by the manual paper feed member Rp1 is conveyed to the registration roll Rr by the sheet conveyance roll Ra and conveyed to the sheet conveyance belt B.

The recording sheet S adsorbed on the sheet conveying belt B sequentially passes through the transfer areas Q3y, Q3m, Q3c, and Q3k that are in contact with the photoreceptors Py to Pk.
The transfer rolls T1y, T1m, T1c, and T1k disposed on the back side of the sheet conveying belt B in the transfer areas Q3y, Q3m, Q3c, and Q3k are supplied with toner at a predetermined timing from the power supply circuit E controlled by the controller C. A transfer voltage having a polarity opposite to the charging polarity is applied.
In the case of a color image, the toner images on the respective photoreceptors Py to Pk are transferred onto the recording sheet S on the sheet conveying belt B by the transfer rolls T1k, T1y, T1m, and T1c. In the case of a monochrome image, only a K (black) toner image is formed on the photoreceptor Pk, and only this K (black) toner image is transferred to the recording sheet S by the transfer device T1k.
After the toner image is transferred, the photoreceptors Py to Pk are neutralized by the neutralizing members Jy to Jk, and then the toner remaining on the surface is collected and cleaned by the photoreceptor cleaners CLy to CLk, and charged again by the charging rolls CRy to CRk. Is done.

The recording sheet S on which the toner image has been transferred is fixed in a fixing region Q5 formed by press-contacting a heating roll Fh and a pressure roll Fp of the fixing device F, and then guided by a guide roller Rgk to be discharged by a discharge roller. The paper is discharged from Rh to the paper discharge tray TR2.
The sheet conveying belt B after the recording sheet S is separated is cleaned by the sheet conveying belt cleaner CLb.
When double-sided printing is performed, the discharge roll Rh is driven to rotate reversely, the recording sheet S is conveyed to the sheet reversing path SH2 by the switching gate GT1, and retransmitted to the registration roll Rr with the front and back sides reversed.
Note that the fixing device F of the first embodiment, the lower drive roll of the paper discharge roll Rh, the switching gate GT1, and the lower guide surface of the sheet reversing path SH2 are configured by an integrally united fixing unit U3. ing. The driven roll on the upper side of the paper discharge roll Rh is supported by the opening / closing cover U2.

(Description of discharge roller)
FIG. 5 is an explanatory diagram of the discharge roller of the first embodiment.
FIG. 6 is an explanatory diagram of unevenness on the surface of the transport roller of the discharge roller of the first embodiment.
In FIG. 5, the discharge roller Rh according to the first exemplary embodiment includes a drive roll Rh1 disposed on the image forming surface side of the recording sheet S and a driven roll Rh2 disposed to face the drive roll Rh1. The drive roll Rh1 includes a rotary shaft 41 that is rotationally driven, and a transport roll 42 that is supported by the rotary shaft 41. A plurality (only one is shown in FIG. 5) of the transport rolls 42 according to the first embodiment is supported at a predetermined interval in the axial direction of the rotary shaft 41. 5 and 6, the transport roll 42 is composed of a rubber roll, and the surface has irregularities having irregular mottled concave portions 42a. In the transport roll 42 of Example 1, the unevenness is formed in a mold for producing a rubber roll. Further, the depth of the concave portion 42a of the first embodiment is set to about 0.05 mm to 1 mm, and is set to a depth deeper than the thickness of the toner image (about 50 μm at the maximum).

In FIG. 5, the driven roll Rh2 has a driven shaft 46 that is biased toward the drive roll Rh1 by a leaf spring member (not shown). The driven shaft 46 supports a resin-made counter roll 47 that faces the transport roll 42 at a predetermined contact pressure. Further, a sheet bending roll (so-called a convolution roll) 48 is formed on the driven shaft 46. The sheet bending roll 48 is formed to have a larger diameter than the opposing roll 47 and is used for curving the recording sheet S passing therethrough so as to improve straight discharge performance. The roll 47 is supported on both sides in the axial direction.
The sheet discharge device (sheet conveyance device) of the first embodiment is configured by the discharge roller (sheet conveyance member) Rh having the reference numerals 41 to 48, a drive motor (not shown), and the like.

(Operation of Example 1)
FIG. 7 is an operation explanatory view of the first embodiment, FIG. 7A is an enlarged explanatory view of a state before the conventional rubber roll comes into contact with the toner image, and FIG. 7B is an enlarged view after the conventional rubber roll comes into contact with the toner image. 7C is an enlarged explanatory view of the state before the rubber roll of Example 1 contacts the toner image, and FIG. 7D is an enlarged explanatory view of the state after the conventional rubber roll contacts the toner image.
In the printer U as the image forming apparatus of Example 1 having the above-described configuration, the unfixed toner image 50 transferred to the surface of the recording sheet S is fixed by the fixing device F and conveyed to the discharge roller Rh. The recording sheet S conveyed to the discharge roller Rh is conveyed while being sandwiched between the driving roll Rh1 and the driven roll Rh2 of the discharge roller Rh. In FIG. 7, in the discharge roller Rh in which the surface of the conventional rubber roll has no irregularities, as shown in FIG. 7B, a contact portion 51 sandwiched by the recording sheet and a non-contact portion 52 not sandwiched Difference in toner image surface roughness. Therefore, since the surface roughness is different, the light reflectance of the toner image, that is, the glossiness is different between the non-contact portion 52 having a rough surface and the contact portion 51 having a relatively smooth surface at the step 53. There was a problem that gloss unevenness was easily noticeable. On the other hand, as shown in FIGS. 7C and 7D, in the discharge roller Rh of the first embodiment, the concave portions 42a are irregularly formed, so that the contact portion 51 and the non-contact portion 52 are mixed. Accordingly, since the portions having different light reflectances are mixed and hardly noticeable, the gloss unevenness becomes inconspicuous and the gloss unevenness can be reduced.

FIG. 8 is an explanatory diagram of the discharge roller of the second embodiment.
In the description of the second embodiment, components corresponding to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The second embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.
In FIG. 8, in the driving roller Rh1 of the discharge roller Rh of Example 2, a large number of convex portions 62a are regularly formed on the surface of the transport roll 62 along the axial direction and the circumferential direction. The interval between the convex portions 62a is formed to be sufficiently narrower than the width of the contact area with the driven roll Rh2 (so-called nip width), and has a contact area that can sufficiently secure the conveyance force of the recording sheet S. Is set to

(Operation of Example 2)
In the printer U as the image forming apparatus according to the second embodiment having the above-described configuration, since a large number of convex portions 62a are formed, the contact portion 51 that is contacted and pressed by the convex portions 62a and the non-contact portion 52 are provided. Mixed, making uneven gloss less noticeable. As a result, similar to the first embodiment, gloss unevenness can be reduced.

FIG. 9 is an explanatory diagram of the discharge roller according to the third embodiment.
In the description of the third embodiment, components corresponding to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The third embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.
In FIG. 9, in the driving roller Rh1 of the discharge roller Rh of the third embodiment, a large number of grooves 72a are regularly formed along the axial direction on the surface of the transport roll 72. The width of the groove 72a is sufficiently narrower than the width of the contact area with the driven roll Rh2 (so-called nip width).

(Operation of Example 3)
In the printer U as the image forming apparatus according to the third embodiment having the above-described configuration, since a large number of groove portions 72a are formed, the contact portion 51 that is contacted and pressed by the groove portions 72a and the non-contact portion 52 are mixed. , Gross unevenness becomes inconspicuous. As a result, similar to the first and second embodiments, gloss unevenness can be reduced.

FIG. 10 is an explanatory diagram of the discharge roller according to the fourth embodiment.
In the description of the fourth embodiment, components corresponding to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The fourth embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.
In FIG. 10, in the driving roller Rh1 of the discharge roller Rh of the fourth embodiment, the surface of the transport roll 42 ′ is formed with minute and irregular unevenness similar to that of the transport roll 42 of the first embodiment, and in the axial direction. A plurality of effective hardness-reducing grooves 42b are formed along. The effective hardness reducing groove 42b of the fourth embodiment is formed deeper than the depth of the recess 42a formed on the surface.

(Operation of Example 4)
In the printer U as the image forming apparatus of the fourth embodiment having the above-described configuration, the effective hardness reducing groove 42b is formed, so that the effective hardness of the transport roll 42 'is lower than that of the transport roll 42 of the first embodiment. Therefore, the force (contact pressure) sandwiching the recording sheet S is reduced. Therefore, the gloss unevenness is less noticeable, and the gloss unevenness can be reduced.

FIG. 11 is an explanatory diagram of the discharge roller of the fifth embodiment.
In the description of the fifth embodiment, components corresponding to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The fifth embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.
In FIG. 11, in the driving roller Rh1 of the discharge roller Rh of Example 5, the transport roll 82 has a non-recessed portion 82a that is not formed with the unevenness formed at the central portion in the axial direction. And the uneven | corrugated | grooved part 82b in which irregular unevenness | corrugation was formed similarly to the conveyance roll 42 of Example 1 is provided in the axial direction both sides of the non-uneven | corrugated part 82a of the conveyance roll 82.

(Operation of Example 5)
In the printer U as the image forming apparatus of Example 5 having the above-described configuration, gloss unevenness is inconspicuous by the concave and convex portions 82b at both ends in the axial direction, and the recording sheet S is reliably in contact with the non-convex portion 82a at the central portion. Can be transported. As a result, as in the first and second embodiments, it is possible to reduce the gloss unevenness while ensuring a sufficient conveyance force.

(Example of change)
As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example, A various change is performed within the range of the summary of this invention described in the claim. It is possible. Modification examples (H01) to (H06) of the present invention are exemplified below.
(H01) In the above-described embodiments, the present invention is not limited to a printer, but can be applied to an image forming apparatus such as a copying machine, a FAX, or a multifunction peripheral. Further, the present invention is not limited to a color image forming apparatus, and can be applied to a monochrome image forming apparatus. Furthermore, the present invention is not limited to an image forming apparatus that directly transfers from a photosensitive member to a recording sheet, and can also be applied to an image forming apparatus having an intermediate transfer member (intermediate transfer belt or drum).

(H02) In the above embodiment, the unevenness formation pattern, the interval between the convex portions 62a, the groove portions 72a, and the like can be reduced within the gloss unevenness and the conveyance force can be sufficiently secured (preferably, contact with the sheet) The area ratio is 30 to 80%), and can be changed as appropriate according to the design. For example, the convex portions 62a can be formed irregularly, and the groove portions 72a can be formed not in the axial direction but in the circumferential direction or oblique direction (spiral). Further, the depth of the recess 42a can be the same as the thickness of the toner image, or can be formed shallow enough to reduce gloss unevenness.
(H03) In each of the above examples, the unevenness was formed by a mold, but the present invention is not limited to this, and can be manufactured by any manufacturing method of post-processing (such as cutting afterwards).
(H04) In the above-described embodiment, the discharge roll Rh is exemplified as the sheet conveying member, but is not limited thereto, and can be applied to the sheet conveying member arranged downstream of the fixing device, and is arranged immediately after the fixing device downstream. The present invention is not limited to those described above, and can be applied to a plurality of downstream roll pairs.

(H05) The effect of the effective hardness reducing groove 42b described in the third embodiment is not limited to being applied to the minute irregular irregularities similar to the first embodiment, but the second or third embodiment. The same effect can be obtained by applying this together.
(H06) In the fifth embodiment, the non-concave portion 82a is arranged in the central portion in the axial direction so that it can be reliably conveyed by contacting the recording sheet S. However, this position may be changed according to the situation. For example, if the position of occurrence of gloss unevenness is limited in the axial direction due to the shape of the corrugation roll 48 shown in FIG. 5, the non-concave portion 82 a can be arranged at the end in the axial direction accordingly.

FIG. 1 is an overall explanatory view of an image forming apparatus according to a first embodiment. FIG. 2 is an explanatory diagram illustrating a state where the cover of the image forming apparatus according to the first exemplary embodiment is opened. FIG. 3 is an explanatory diagram of the detachable unit according to the first embodiment. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is an explanatory diagram of the discharge roller of the first embodiment. FIG. 6 is an explanatory diagram of unevenness on the surface of the transport roller of the discharge roller of the first embodiment. FIG. 7 is an operation explanatory view of the first embodiment, FIG. 7A is an enlarged explanatory view of a state before the conventional rubber roll comes into contact with the toner image, and FIG. 7B is an enlarged view after the conventional rubber roll comes into contact with the toner image. 7C is an enlarged explanatory view of the state before the rubber roll of Example 1 contacts the toner image, and FIG. 7D is an enlarged explanatory view of the state after the conventional rubber roll contacts the toner image. FIG. 8 is an explanatory diagram of the discharge roller of the second embodiment. FIG. 9 is an explanatory diagram of the discharge roller according to the third embodiment. FIG. 10 is an explanatory diagram of the discharge roller according to the fourth embodiment. FIG. 11 is an explanatory diagram of the discharge roller of the fifth embodiment.

Explanation of symbols

42, 62, 72, 42 ', 82 ... transport rolls,
42a ... recess,
47 ... Opposite roll,
62a ... convex portion,
72a ... groove portion,
82a ... non-concave portion,
F: Fixing device,
Rh: sheet conveying member,
S: Recording sheet.

Claims (3)

A sheet conveying member disposed downstream in the recording sheet conveying direction of a fixing device for heating and fixing an unfixed toner image on the surface of the recording sheet, the sheet conveying member being disposed on a toner image forming surface side of the recording sheet and having an axial direction on the surface A non-concave portion disposed at a specific portion and transported in contact with the recording sheet, and a thickness of a toner layer formed on the recording sheet surface adjacent to the non-concave portion in an axial portion excluding the non-concave portion A sheet conveyance member having a conveyance roll integrally provided with an unevenness constituted by a deeper recess, and an opposing roll disposed in opposed contact with the conveyance roll;
A sheet conveying apparatus comprising: The sheet conveying apparatus according to claim 1, further comprising the conveying roll having the non-concave portion disposed in an axially central portion.   An image forming apparatus comprising the sheet conveying device according to claim 1.

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