JP2021117458A - Image forming unit and image forming apparatus - Google Patents

Abstract

To increase or improve sealability for developer with a simpler configuration.SOLUTION: There is provided an image forming unit comprising: a rotating body having an outer peripheral surface that can carry developer; a seal support part that is provided at least at one end in an axial direction of the rotating body and has a support surface opposite to the outer peripheral surface; and a first sealant that is supported by the support surface, the first sealant having a predetermined length along an outer peripheral surface of the rotating body in its circumferential direction and arranged between the rotating body and the seal support part. The support surface provided on the seal support part has a concave part that reaches the rear end of the first sealant in the direction of rotation of the rotating body.SELECTED DRAWING: Figure 6

Description

The present disclosure relates to an image forming unit and an image forming apparatus.

As an image forming unit provided in the image forming apparatus, Patent Document 1 describes a unit in which measures are taken to suppress leakage of the developer supported on the photoconductor drum from the image forming unit. Specifically, the sealant is placed in contact with the photoconductor drum at the end in the axial direction.

Japanese Unexamined Patent Publication No. 2015-145996

There is still a demand for further improvement or improvement of the sealability for the developer.

It is an object of the present disclosure to provide an image forming unit and an image forming apparatus capable of improving or improving the sealing property against a developer with a simpler configuration.

In one embodiment of the present disclosure, a rotating body having an outer peripheral surface configured to support a developer and a seal support portion provided at at least one end of the rotating body in the axial direction and having a supporting surface facing the outer peripheral surface. A first sealing material supported on the support surface, having a predetermined length in the circumferential direction along the outer peripheral surface of the rotating body, and arranged between the rotating body and the seal support portion. An image forming unit comprising a sealing material is provided. In the present embodiment, the support surface provided on the seal support portion has a concave portion that reaches the rear end of the first seal material in the rotation direction of the rotating body.

In another embodiment of the present disclosure, the image forming unit, a fixing device configured to be able to fix the developer on the medium, and a conveying mechanism configured to be able to convey the medium via the image forming unit and the fixing device. An image forming apparatus comprising, is provided.

According to the image forming unit and the image forming apparatus according to the present disclosure, when the first sealing material is supported on the support surface, the supported first sealing material has a restoring force to return to the original shape. It becomes possible to suppress. Thereby, the sealing property against the developing agent can be improved or improved by a simple structure.

FIG. 1 is a schematic view schematically showing an internal configuration of an image forming apparatus according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional elevation view showing the overall configuration of the image forming unit provided in the same image forming apparatus. FIG. 3 is a perspective view showing the overall configuration of the cleaning unit of the image forming unit. FIG. 4 is a perspective view showing the configuration of the cleaning portion as described above with the cleaning blade removed. FIG. 5 is a perspective view showing the overall configuration of the frame provided in the cleaning portion. FIG. 6 is a cross-sectional view of the same cleaning portion as shown by X-rays shown in FIG. 3, showing a configuration at an axial end portion of the photoconductor drum. FIG. 7 is a cross-sectional view of the same cleaning portion as shown by the YY line shown in FIG. 3, showing a configuration at the center of the photoconductor drum in the axial direction. FIG. 8 is a cross-sectional view of the frame body taken along line XX shown in FIG. 3, FIG. 8 (a) shows the frame body provided in the same cleaning section, and FIG. The frames that can be applied to are shown respectively. 9A and 9B show the structure of the sealing material used for the cleaning portion, FIG. 9A is a perspective view, and FIG. 9B is a plan view and a side view, respectively. FIG. 10 is an enlarged plan view partially showing the configuration of the cleaning portion according to another modified example.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

(Overall configuration of printing apparatus 101)
FIG. 1 is a schematic view schematically showing an internal configuration of a printing device 1 which is an image forming device according to an embodiment of the present disclosure. The printing apparatus 1 according to the present embodiment is not limited to a specific type, and carries a developer on the outer peripheral surface of a printer (for example, an electrophotographic printer), a copier, a multifunction device (MFP), a facsimile, or the like. It may be of any kind, provided with a freely configured rotating body. Further, in the present embodiment, the case where the color image is formed by the printing device 1 will be described as an example, but the printing device 1 modifies the configuration of the image forming unit (specifically, the image forming unit 121). It is also possible to form a monochromatic image.

The printing device 1 can be largely divided into a medium storage unit 11, an image forming unit 12, an image fixing unit 13, and a paper ejection loading unit 14. In the present embodiment, paper (hereinafter referred to as “recording paper”) P is adopted as the recording medium on which the image is formed by the printing apparatus 1. The recording paper P circulates from the medium storage unit 11 to each of the above units via the paper transport path.

The medium storage unit 11 includes a paper feed cassette 111, and the recording paper P, which is a recording medium, is held in the paper feed cassette 111.

The recording paper P is separated from the paper cassette 111 one by one and sent out to the paper transport path based on a printing instruction or the like from the user. The medium storage unit 11 includes a paper feed transport roller 112, and the paper feed transport roller 112 feeds the recording papers P stacked on the paper feed cassette 111 one by one to the paper transport path.

The recording paper P sent out from the paper cassette 111 is composed of a resist roller 113 that corrects skew (that is, inclination or distortion) of the recording paper P and a pressure roller 114 that presses the recording paper P against the resist roller 113. It passes through the space and is supplied to the image forming unit 12 at the timing of development. The resist roller 113, the pressure roller 114, and the discharge rollers 115a and 115b and the dependent rollers 116a and 116b described later correspond to the "conveying mechanism" according to the present embodiment.

The image forming unit 12 includes an image forming unit 121 (121a to 121d) and a transfer device 122.

In the present embodiment, the image forming unit 121 is composed of a plurality of monochromatic units 121a to 121d according to the type of primary color. The image forming unit 121a develops a first color (for example, cyan), the image forming unit 121b develops a second color (for example, magenta), and the image forming unit 121c develops a third color. (For example, yellow) is developed, and the image forming unit 121d develops a fourth color (for example, black). The image forming units 121a to 121d of the first to fourth colors have the same configuration except for the difference in the color to be developed. In the following description, the cyan image forming unit 121a (for convenience, the reference numeral is 121). The explanation will be made on behalf of).

FIG. 2 is a cross-sectional elevation view showing the overall configuration of the image forming unit 121 provided in the printing apparatus 1.

The image forming unit 121 includes a photoconductor drum 1211 which is an electrostatic latent image carrier, and also includes a developing unit A and a cleaning unit B. The photoconductor drum 1211 corresponds to the "rotating body" according to the present embodiment, and an electrostatic latent image is formed on the outer peripheral surface of the photoconductor drum 1211 by irradiating the outer peripheral surface with exposure light according to the image information. The electrostatic latent image carrier is not limited to a drum-shaped one, but may be a belt-shaped one. That is, it is possible to adopt a photoconductor belt instead of the photoconductor drum 1211 as the electrostatic latent image carrier, and the photoconductor belt in this case is the "rotating body" according to the modified example of the present embodiment. Equivalent to.

The developing unit A includes a developer roller 1212 and a supply roller 1213. The developer roller 1212 is arranged in a state where the outer peripheral surfaces of the photoconductor drum 1211 are in contact with each other, and the electrostatic latent image formed on the photoconductor drum 1211 is developed with toner which is a developer. The supply roller 1213 is arranged between the toner container 1214 and the developer roller 1212 in a state where the outer peripheral surfaces of the developer roller 1213 are in contact with each other, and the toner is supplied and supplied from the toner container 1214. The toner is adhered to the outer peripheral surface of the developer roller 1212. The developing unit A further includes a regulating blade 1215 for thinly leveling the toner adhering to the outer peripheral surface of the developer roller 1212.

Returning to FIG. 1, the transfer device 122 is arranged to face the image forming unit 121, and in the transfer region defined with respect to the recording paper P, the developer image formed by the image forming unit 121 is transferred to the recording paper P. Transcribe.

The transfer device 122 includes a pair of guide rollers 1221 and 1222, and also includes an endless transfer belt 1223 spanned between the pair of guide rollers 1221 and 1222. Here, the range in which the photoconductor drum 1211 of the image forming unit 121 and the transfer belt 1223 of the transfer device 122 face each other is the transfer region.

When the recording paper P is supplied to the image forming unit 12, the image forming unit 121 charges the outer peripheral surface of the photoconductor drum 1211 by the charging roller 1216 (FIG. 2). After charging the photoconductor drum 1211, the outer peripheral surface is irradiated with light from an exposure device (not shown), and an electrostatic latent image corresponding to the image information is formed on the outer peripheral surface. Then, this electrostatic latent image is developed by a developer to form a developer image (sometimes called a toner image). The developer image formed on the photoconductor drum 1211 is transferred to the recording paper P carried on the transfer belt 1233. After the transfer, the developer remaining on the photoconductor drum 1211 is removed in the cleaning unit B, which will be described in more detail later, and the photoconductor drum 1211 is then used for the next development and transfer. After the above steps are performed for colors other than cyan, that is, magenta, yellow, and black, and the transfer of all the developing agents necessary for forming the desired image is completed, the recording paper P is transferred to the transfer device 122. Is transported to the image fixing unit 13.

The image fixing unit 13 includes a fixing device 131, and fixes the developer image transferred to the recording paper P by a high-temperature and high-pressure fixing process.

The fixing paper P is further conveyed via the first discharge roller 115a and the first dependent roller 116a paired thereto, and the second discharge roller 115b and the second dependent roller 116b cover the upper part from the discharge port 117. It is discharged to the paper discharge loading unit 14 formed in. The paper discharge loading unit 14 is a place where the recording paper P on which the target image is formed is temporarily loaded.

As described above, in the cleaning unit B, the image forming unit 121 removes the toner remaining on the photoconductor drum 1211 after transfer to the recording paper P from the photoconductor drum 1211, and the removed toner (hereinafter, "" It has a configuration for collecting (sometimes referred to as "waste toner").

The configuration of the cleaning unit B according to the present embodiment will be described below with reference to FIGS. 3 to 8 as appropriate.

FIG. 3 is a perspective view showing the overall configuration of the cleaning unit B, FIG. 4 is a perspective view showing the configuration of the cleaning unit B with the cleaning blade 1218 removed, and FIG. 5 is a perspective view showing the cleaning unit B. It is a perspective view which shows the overall structure of the frame body 1217 provided in B. Further, FIG. 6 is a cross-sectional view of the cleaning portion B by the XX line shown in FIG. 3, and FIG. 7 is a cross-sectional view of the cleaning portion B by the YY line shown in FIG. FIG. 6 shows the configuration of the cleaning portion B at the axial end of the photoconductor drum 1211, and FIG. 7 shows the configuration of the cleaning portion B at the axial center of the photoconductor drum 1211. FIG. 8 is a cross-sectional view of the frame body 1217 by X-rays shown in FIG. 3, FIG. 8 (a) shows a frame body provided in the cleaning portion B according to the present embodiment, and FIG. The frame bodies applicable to the cleaning unit B according to the modified example are shown respectively.

The cleaning unit B includes a frame body 1217, a cleaning blade 1218, and a discharge spiral 1219 as a basic configuration.

The frame body 1217 supports the photoconductor drum 1211 with respect to the main body of the printing device 1, extends over the entire axial direction of the photoconductor drum 1211, and as shown in FIG. Support arms 1217a that rotatably support the photoconductor drum 1211 are provided at both ends in the axial direction.

The cleaning blade 1218 removes the toner remaining on the outer peripheral surface of the photoconductor drum 1211, and supports the elastic material 1218a and the elastic material 1218a in contact with the photoconductor drum 1211. And. The cleaning blade 1218 is attached to the frame body 1217 by attaching the elastic material 1218a to the support surface formed on the sheet metal portion 1218b with an adhesive and screwing the sheet metal portion 1218b to the frame body 1217. ing. In the present embodiment, the cleaning blade 1218 removes the toner by contacting the outer peripheral surface of the photoconductor drum 1211 over the entire axial direction of the photoconductor drum 1211. The cleaning blade 1218 corresponds to the "cleaning material" according to the present embodiment.

The discharge spiral 1219 sends the toner removed by the cleaning blade 1218 to the outside of the frame body 1217, that is, the image forming unit 121 as waste toner. As shown in FIG. 4, the discharge spiral 1219 is composed of a wire rod formed in a spiral shape, and is housed in a first waste toner discharge path H formed in the frame body 1217 (FIG. 5). Then, the discharge spiral 1219 is rotated by a drive source (for example, an electric motor) (not shown) to urge the waste toner to the outside and sequentially deliver the waste toner. The waste toner sent out to the outside of the image forming unit 121 is conveyed through the second waste toner transport path R, and is collected in the waste toner container 15 provided inside the main body of the apparatus.

In the present embodiment, leakage of toner (including waste toner removed from the photoconductor drum 1211) from the image forming unit 121 is suppressed by a plurality of sealing materials 201 to 204.

In the present embodiment, such a sealing material includes a first sealing material 201, a second sealing material 202, a third sealing material 203, and a fourth sealing material 204. All of these sealing materials 201 to 204 are attached or joined with an adhesive to a support surface or a joint surface formed on the frame body 1217. The first sealing material 201 corresponds to the "first sealing material", the "first end sealing material" and the "second end sealing material" according to the present embodiment, and the second sealing material 202 is the present embodiment. Corresponds to the "second sealing material" according to.

As shown in FIG. 4, the third sealing material 203 is interposed between the elastic material 1218a of the cleaning blade 1218 and the frame body 1217 at both ends in the axial direction of the photoconductor drum 1211, and the elastic material 1218a and the frame are interposed. It suppresses the leakage of toner through the body 1217. On the other hand, as shown in FIG. 7, the fourth sealing material 204 is provided over the entire axial direction of the photoconductor drum 1211 and holds the sheet metal portion 1218b and the frame body 1217 of the cleaning blade 1218 that holds the elastic material 1218a. It is interposed between the sheet metal portion 1218b and the frame body 1217 to suppress the leakage of toner.

The third sealing material 203 and the fourth sealing material 204 can be the same as those generally provided in the frame body in order to secure the sealing property against the toner.

When the first sealing material 201 represents the direction of approaching the center of the photoconductor drum 1211 in the axial direction as the inner side and the direction away from the center of the photoconductor drum 1211 as the outer side, the toner in the axial direction of the photoconductor drum 1211 is outward. It mainly suppresses leakage. In the present embodiment, as shown in FIG. 5, the frame body 1217 has support surfaces SF1 and SF1 formed so as to face each end of the photoconductor drum 1211 in the axial direction, and is a first sealing material. 201 is attached to these support surfaces SF1 and SF1, respectively. That is, in the present embodiment, the "seal support" on which the "first seal material" is supported is configured as a portion of the frame body 1217. As a material applicable to the first sealing material 201, a foaming material can be exemplified. Further, in the present embodiment, of the pair of support surfaces SF1 and SF1, for example, the support surface SF1 on the right side facing the paper surface of FIG. 5 corresponds to the "first support surface", and the support surface SF1 on the opposite left side corresponds to the "first support surface". Corresponds to the "second support surface". The first sealing material supported by the first support surface SF1 corresponds to the "first end sealing material", and the first sealing material supported by the second supporting surface SF1 is the "second end sealing material". Corresponds to. In the present embodiment, the names of the first and second end sealing materials 201 are unified with the first sealing material.

The second sealing material 202 mainly suppresses toner leakage to the rear in the circumferential direction of the photoconductor drum 1211 when the rotation direction of the photoconductor drum 1211 is the front and the opposite direction is the rear. .. In the present embodiment, the frame body 1217 has a support surface SF2 formed over the entire axial direction of the photoconductor drum 1211 (FIG. 5), and the second sealing material 202 has a sheet shape and supports the support surface SF2. It is attached to the surface SF2. An elastic material can be exemplified as a material applicable to the second sealing material 202.

Here, in a general frame, no consideration is given to the shape of the support surface of the sealing material for the purpose of suppressing toner leakage. Assuming that the support surface of the sealing material (that is, the end sealing material) provided at the end in the axial direction has a shape that is convex toward the outer peripheral surface of the photoconductor drum, the sealing material is actually attached. In that case, as a result of the restoring force that tries to return the sealing material to the original shape after sticking, the end portion of the sealing material is separated from the frame body, and a gap is generated between the end portion of the sealing material and the frame body. Is a concern. This gap serves as a passage for toner, especially waste toner removed from the photoconductor drum by the cleaning blade, and may cause toner leakage. Therefore, in order to effectively prevent toner leakage, the sealing material and the frame are separated from each other. In between, it is necessary to add a special member or element for closing the gap. This leads to an increase in the number of parts, and it is desirable to avoid the increase in the number of parts because there is a concern that the manufacturing process becomes complicated and the cost increases. In this embodiment, such a problem is considered.

9A and 9B show the configuration of the first sealing material 201, FIG. 9A is a perspective view of the first sealing material 201, and FIG. 9B is a plan view of the first sealing material 201 (paper right). ) And the side view (left side of the paper).

The first sealing material 201 forms a rectangle in the plan view of FIG. 9B in a natural state (that is, no load) before being attached to the frame body 1217, and forms a substantially rectangular shape as a whole (FIG. FIG. (A)). Then, in the side view, the first sealing material 201 has a tapered surface 201a whose starting point is a position separated from one short side by a predetermined distance d, and as the first sealing material 201 approaches the short side from the starting point, the first sealing material 201 The thickness is gradually reduced.

Here, as best shown in FIG. 6, the diameter of the photoconductor drum 1211 is attached to the support surface (hereinafter referred to as “support surface of the end seal material”) SF1 of the frame body 1217 to which the first seal material 201 is attached. A portion having an increasing depth, that is, a concave portion C is formed on the outer side in the direction. In the present embodiment, the concave portion C extends to a position reaching the rear end 201e of the first sealing material 201 in the rotation direction of the photoconductor drum 1211 (indicated by an arrow in FIG. 6), and the concave portion C of the first sealing material 201. It is connected to the support surface SF2 of the second sealing material 202 with the portion corresponding to the rear end 201e as a boundary. Further, in the present embodiment, the concave portion C has a curved surface shape, and has a center of curvature thereof on the central axis of the outer peripheral surface of the photoconductor drum 1211, in other words, on the rotation center axis AX of the photoconductor drum 1211. .. FIG. 6 shows the radius of curvature of the support surface SF1 in the concave portion C by the reference numeral r.

The first sealing material 201 is attached to the support surface SF1 with one surface (that is, the upper surface) 201b having the tapered surface 201a facing the outer peripheral surface of the photoconductor drum 1211. The elastic material 1218a of the above is in contact with the photoconductor drum 1211 at each end in the axial direction (FIG. 3).

On the other hand, the second sealing material 202 has an elongated rectangular shape in a plan view and has a uniform thickness as a whole. The second sealing material 202 is attached to the frame body 1217 by being attached to the support surface SF2, and in the state after the attachment, as shown in FIG. 6, at the front end in the rotation direction of the photoconductor drum 1211 in the axial direction. The entire surface of the photoconductor drum 1211 is in contact with the outer peripheral surface of the photoconductor drum 1211. That is, the second sealing material 202 is attached to the support surface SF2 at the rear end portion of the photoconductor drum 1211 in the rotation direction.

Further, in the present embodiment, with the first sealing material 201 and the second sealing material 202 attached to the frame body 1217, the second sealing material 202 is located near the front end thereof at the axial end portion of the photoconductor drum 1211. The portion of the first sealing material 201, specifically, the portion of the first sealing material 201 on which the tapered surface 201a is formed overlaps. Then, by attaching the photoconductor drum 1211 to the frame body 1217, both the first sealing material 201 and the second sealing material 202 are compressed by the photoconductor drum 1211, and the first sealing material is formed with respect to the outer peripheral surface of the photoconductor drum 1211. The repulsive force due to the compression of the sealing material 201 acts through the second sealing material 202. FIG. 6 shows a part of the second sealing material 202 (indicated by the alternate long and short dash line) in a state of being buried in the first sealing material 201, which is the elasticity of the first sealing material 201 and the second sealing material 202. This is due to the difference in power.

Here, of the first sealing material 201, the angle formed by the upper surface 201b parallel to the lower surface 201c attached to the support surface SF1 and the tapered surface 201a is α (FIG. 9B), and the first seal material 201 is formed. When the angle formed by the tangent line at the end of the concave portion C and the support surface SF2 of the second sealing material 202 in the support surface SF1 of the sealing material 201 is represented as β (FIG. 8A), the angles α and The relationship of the following equation (1) is established between β.
α> β… (1)

As a result, a gap is formed between the tapered surface 201a of the first sealing material 201 and the lower surface of the second sealing material 202 facing the tapered surface 201a in a state where the photoconductor drum 1211 is removed from the frame body 1217. Then, when the photoconductor drum 1211 is attached to the frame body 1217, the outer peripheral surface of the photoconductor drum 1211 comes into contact with the second sealing material 202, the second sealing material 202 is bent, and the second sealing material 202 is first. By pressing the sealing material 201 together with the frame body 1217, this gap is eliminated and the sealing property is exhibited.

(Explanation of action and effect)
The printing apparatus 1 according to the present embodiment and the image forming unit 121 provided therein are configured as described above, and the main effects obtained by the present embodiment are summarized below.

First, a support surface SF1 on which the first seal material 201 is supported is formed on the frame body 1217, and the support surface SF1 has a concave shape that reaches the rear end 201e of the first seal material 201 in the rotation direction of the photoconductor drum 1211. By providing the portion C, when the first sealing material 201 is actually supported (joined in the present embodiment) on the support surface SF1, the first sealing material 201 after the support tends to return to the original shape. It is possible to suppress the generation of restoring force. As a result, the end portion (rear end 201e) of the first sealing material 201 is separated from the frame body 1217, so that a gap is suppressed between the end portion of the first sealing material 201 and the frame body 1217, and the gap is suppressed. It is not necessary to add a special member or element for closing the toner (that is, while suppressing an increase in the number of parts), and the sealability to the toner can be improved or improved by a simple configuration.

Secondly, by making the concave portion C of the support surface SF1 curved, the support strength of the first sealing material 201 with respect to the support surface SF1, that is, the bonding strength by the adhesive is secured, and the first seal after support is secured. It is possible to appropriately suppress the restoring force generated in the material 201.

Thirdly, when the concave portion C of the support surface SF1 is curved, the center of curvature of the concave portion C is set on the rotation center axis AX of the photoconductor drum 1211, so that the first sealing material 201 after support However, since it extends along the outer peripheral surface of the photoconductor drum 1211 in the rotation direction of the photoconductor drum 1211, the first sealing material 201 exhibits a substantially uniform sealing property over the entire concave portion C. It is possible to suppress the leakage of toner.

Fourth, a tapered surface 201a that reduces the thickness of the first sealing material 201 as it approaches the rear end 201e is formed on one surface of the first sealing material 201 toward the outer peripheral surface of the photoconductor drum 1211. It is possible to set the repulsive force exerted by the sealing material 201 on the photoconductor drum 1211 to an appropriate magnitude and prevent the rotation of the photoconductor drum 1211 from being excessively hindered.

Fifth, the second sealing material 202 makes it possible to more reliably suppress the leakage of toner from the image forming unit 121.

Sixth, the end portion of the second sealing material 202 is sandwiched between the axial end portion of the photoconductor drum 1211 and the tapered surface 201a portion of the first sealing material 201. The sealing material 201 suppresses toner leakage in the axial direction (particularly outward) of the photoconductor drum 1211, while the second sealing material 202 suppresses toner leakage in the circumferential direction (particularly behind the photoconductor drum 1211). It is possible to suppress leakage.

Seventh, the angle α of the tapered surface 201a of the first sealing material 201 is set, and this is set between the first sealing material 201 and the second sealing material 202 with the photoconductor drum 1211 removed from the frame body 1217. By setting the angle at which a gap is formed in the photoconductor, the repulsive force exerted by the first sealing material 201 on the photoconductor drum 1211 when the photoconductor drum 1211 is attached to the frame body 1217 is appropriately suppressed, and the photoconductor is formed. The resistance force (mainly due to frictional force) exerted by the second sealing material 202 sandwiched between the drum 1211 and the first sealing material 201 against the rotation of the photoconductor drum 1211 is suppressed, and the photoconductor drum 1211 rotates smoothly. It is possible to encourage.

In the above description, the concave portion C of the support surface SF1 of the first sealing material 201 is formed by a curved surface that is uniform to the extent that the center of curvature can be determined. However, the shape applicable to the concave portion C is not limited to this. For example, it is also possible to form the concave portion C by a curved surface in which one center of curvature cannot be determined, specifically, a plurality of continuous curved surfaces having different radii of curvature. Further, as a shape applicable to the concave portion C, a shape composed of a plurality of surfaces intersecting with each other can be exemplified.

FIG. 8B shows, as the frame body 1217 according to the modified example of the present embodiment, the configuration of the frame body 1217 having the concave portions C composed of a plurality of surfaces intersecting with each other is the same as that of FIG. It is shown by a cross section by a line. In this modification, the concave portion C is formed by two surfaces intersecting each other, and the angle γ formed on the side of these two surfaces facing the photoconductor drum 1211 is set so as to satisfy the following conditions.
90 ° <γ <180 °… (2)

By forming the concave portion C of the support surface SF1 from a plurality of surfaces that intersect with each other in this way, not only the choices regarding the shape of the concave portion C are increased and the degree of freedom in design is increased, but also the support surface SF1 is formed. The repulsive force exerted on the photoconductor drum 1211 by the supported first sealing material 201 is changed in the rotation direction of the photoconductor drum 1211, and it becomes easy to optimize the sealing property. For example, in this modification, a relatively strong repulsive force is generated at both ends of the first sealing material 201 in the rotation direction of the photoconductor drum 1211, while the outer periphery of the support surface SF1 and the photoconductor drum 1211 is in the middle between them. Since it is separated from the surface, a relatively weak repulsive force can be generated.

Further, in the above description, the support surface SF1 of the first sealing material 201 and the support surface SF2 of the second sealing material 202 are formed to be continuous with each other in a state where the frame body 1217 is viewed in the axial direction of the photoconductor drum 1211. However, the present invention is not limited to this, and it is also possible to form the two so as to overlap each other. As an example of such a case, FIG. 10 partially shows the configuration of the cleaning unit according to another modification of the present embodiment by an enlarged plan view. FIG. 10A shows the above example, and FIG. 10B shows another modification.

As shown in FIG. 10B, the support surface SF1 of the first sheet material 201 is projected so as to be closer to the support surface SF2 of the second sealing material 202 than in the example shown in FIG. 10A. Both support surfaces SF1 and SF2 overlap each other in the axial direction of the photoconductor drum 1211. FIG. 10B shows a recessed portion formed on the support surface SF2 of the frame body 1217 to the second sealing material 202 by projecting the support surface SF1 of the first sheet material 201 by reference numeral D.

As a result, the toner transmitted through the edge portion 1217e of the frame body 1217 defining the first waste toner discharge path H is effectively blocked by the first sealing material 201, and the toner leaks through the first sealing material 201 more reliably. It can be suppressed.

Further, what can be applied as a rotating body is not limited to an electrostatic latent image carrier such as a photoconductor drum 1211, but by having an outer peripheral surface configured to support a developer such as toner. It may be any rotating body arranged at a site where leakage of the developer is a concern. A developer roller can be exemplified as a rotating body other than the photoconductor drum 1211.

Although the embodiments of the present disclosure have been described above, these embodiments show only a part of the examples to which the present disclosure is applied, and the technical scope of the present disclosure is shown as specific examples. It is not intended to be limited to the composition. It is possible to make various changes and amendments to the disclosed embodiments within the scope of the matters described in the claims.

1 ... Printing device, 11 ... Medium storage unit, 111 ... Paper cassette, 112 ... Separation roller, 12 ... Image forming unit, 121 ... Image forming unit, 1211 ... Photoreceptor drum, 1217 ... Frame body, 1218 ... Cleaning blade, 13 ... Image fixing part, 131 ... Fixing device, 14 ... Paper discharge loading part, 201 ... First sealing material, first end sealing material, second end sealing material, 201a ... Tapered surface, 202 ... Second sealing material , C ... concave portion, H ... first waste toner non-exit path, P ... recording paper, SF1, SF2 ... support surface.

Claims (15)

A rotating body having an outer peripheral surface configured to support a developer, and
A seal support portion provided at at least one end in the axial direction of the rotating body and having a support surface facing the outer peripheral surface, and a seal support portion.
A first seal material supported on the support surface, having a predetermined length in the circumferential direction along the outer peripheral surface, and arranged between the rotating body and the seal support portion. Wood and
With
The support surface has a concave portion that reaches the rear end of the first sealing material in the rotation direction of the rotating body.
Image forming unit. The concave portion has a curved surface shape.
The image forming unit according to claim 1. The concave portion has a center of curvature on the rotation center axis of the rotating body.
The image forming unit according to claim 2. The concave portion is composed of a plurality of surfaces that intersect with each other.
The image forming unit according to claim 1. The first sealing material has a tapered surface on one surface toward the rotating body that reduces the thickness of the first sealing material as it approaches the rear end.
The image forming unit according to any one of claims 1 to 4. A frame body extending in the axial direction of the rotating body and configured to support the rotating body at both ends in the axial direction is further provided.
The seal support portion is provided on the frame body, and has a first support surface and a second support surface facing each of the axially end portions of the rotating body as the support surface.
The first sealing material includes a first end sealing material supported by the first supporting surface and a second end sealing material supported by the second supporting surface.
The image forming unit according to any one of claims 1 to 5. A second sealing material supported by the frame body, which extends between the axial ends of the rotating body and can come into contact with the outer peripheral surface of the rotating body at the front end in the rotating direction of the rotating body. Further equipped with a second sealing material arranged in,
The image forming unit according to claim 6. The first end sealing material and the second end sealing material have a tapered surface on one surface toward the rotating body that reduces the thickness of the first and second end sealing materials as it approaches the rear end. Have each
The second sealing material has an end portion sandwiched between the axial end portion of the rotating body and the tapered surface of the first or second end portion sealing material.
The image forming unit according to claim 7. The tapered surface is set at an angle at which a gap is formed between the first or second end sealing material and the end of the second sealing material in a state where the rotating body is detached from the frame. rice field,
The image forming unit according to claim 8. The frame has a supporting surface of the second sealing material in which the second sealing material is supported at a portion other than the front end.
The support surface of the first sealing material and the support surface of the second sealing material are formed so as to overlap each other in the axial direction of the rotating body.
The image forming unit according to any one of claims 7 to 9. It extends between the first end sealing material and the second end sealing material, contacts the outer peripheral surface of the rotating body at the rear end in the rotation direction of the rotating body, and is supported by the rotating body. A cleaning material is further provided so that the developer can be removed from the rotating body.
The frame has a discharge path for the developer, which is formed so that the developer removed by the cleaning material can be guided to the outside of the image forming unit.
The image forming unit according to any one of claims 6 to 10. The rotating body is an electrostatic latent image carrier.
The image forming unit according to any one of claims 1 to 11. The rotating body is a photoconductor drum.
The image forming unit according to claim 12. The image forming unit according to any one of claims 1 to 13, wherein the developing agent supported on the rotating body can be transferred to a medium.
A fixing device configured to fix the developer on the medium, and a fixing device.
A transport mechanism configured to transport the medium via the image forming unit and the fixing device, and
An image forming apparatus. A rotating body having an outer peripheral surface configured to support a developer, and
A frame body that extends in the axial direction of the rotating body and is configured to support the rotating body at both ends in the axial direction.
A first sealing material arranged between the rotating body and the frame body, the first sealing material having a predetermined length in the circumferential direction along the outer peripheral surface, and the first sealing material.
With
The frame body has a support surface on which the first sealing material is supported at at least one end in the axial direction of the rotating body.
The support surface has a concave portion that reaches the rear end of the first sealing material in the rotation direction of the rotating body.
Image forming unit.

Images