Developing device

Abstract

To provide a developing device that can prevent leakage of toner even when increasing the rotation speed of a developing roller.SOLUTION: A developing device comprises: a lower seal (6) that is in contact with a peripheral surface of a developing roller; and side seals (5). The side seals (5) each include a surface layer (5A) having a plurality of fibers and a base sheet having the plurality of fibers implanted therein. On the surface layer (5A), a downstream side end in a rotation direction of the developing roller is attached to a blade body (4A) to be adjacent to one end of a rubber part (4B), and an upstream side end in the rotation direction is adjacent to one end of the lower seal (6).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a development device. [Background technology]

[0002] Image forming devices such as electrophotographic printers are equipped with a developing device that includes a developing roller that carries toner as a developer on its surface. It is known that such developing devices are provided with a seal to prevent toner leakage from around the developing roller, as described in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-134298 A Summary of the Invention [Problem to be solved by the invention]

[0004] In image forming apparatuses, increasing the rotation speed of the developing roller is being considered to meet the demand for faster image forming processes and improved image quality of printed matter resulting from the image forming processes.

[0005] However, in the above-described conventional technology, when the rotation speed of the developing roller is increased, there is a risk of the toner leaking out of the developing device.

[0006] An object of the present disclosure is to provide a developing device that can suppress toner leakage even when the rotation speed of the developing roller is increased. [Means for solving the problem]

[0007] In order to solve the above problem, a developing device of a first aspect of the present disclosure comprises a developing roller that carries toner, a developing frame that rotatably supports the developing roller, a layer thickness regulating blade that is provided on the developing frame and has a rubber portion that contacts the peripheral surface of the developing roller and a blade that supports the rubber portion, a side seal that is arranged between the developing frame and an axial end of the developing roller so as to contact the peripheral surface of the developing roller, and a lower seal that is provided on the developing frame upstream of the rotational direction of the developing roller relative to the layer thickness regulating blade and extends in the axial direction, and contacts the peripheral surface of the developing roller, wherein the side seal has a surface layer that has a plurality of fibers that contact the peripheral surface of the developing roller and a base sheet in which the plurality of fibers are implanted, and the surface layer of the side seal has a downstream end in the rotational direction that is adjacent to one end of the rubber portion in the axial direction, and is configured so that the upstream end in the rotational direction is adjacent to one end of the lower seal in the axial direction.

[0008] According to the above configuration, the surface layer has a base sheet with multiple fibers embedded therein, and the long side seals are integrally formed, so the sealing performance of the side seals can be easily improved, and as a result, toner leakage can be suppressed even when the rotation speed of the developing roller is increased.

[0009] A second aspect of the present disclosure is the developing device of the first aspect, which may further include a lower side seal provided between an end of the lower seal in the axial direction and the developing frame.

[0010] According to the above configuration, the lower side seal can support the axial end of the lower seal on the developing frame, thereby preventing the axial end of the lower seal from separating from the developing roller.

[0011] A third aspect of the present disclosure is the developing device of the second aspect, wherein the lower side seal may be configured using an elastic body.

[0012] According to the above configuration, the lower seal can be in elastic contact with the developing roller, and even when the rotation speed of the developing roller is increased, the sealing properties of the lower seal can be ensured while facilitating smooth rotation of the developing roller.

[0013] A fourth aspect of the present disclosure is a developing device according to any one of the first to third aspects, wherein the side seal further comprises a lower layer that supports the surface layer, and the lower layer may be constructed using an elastic material.

[0014] According to the above configuration, the side seal can elastically contact the axial end of the developing roller, and even when the rotation speed of the developing roller is increased, the sealing properties of the side seal can be ensured while facilitating smooth rotation of the developing roller.

[0015] A fifth aspect of the present disclosure is a developing device according to any one of the first to fourth aspects, which may further include a side edge seal that is constructed using an elastic body and is provided on the developing frame so as to be adjacent to the rubber portion with its axial end face facing the axial end face of the rubber portion.

[0016] With the above configuration, the side edge seals can prevent toner leakage from the rubber portion. Even if the rubber portion wears, the side edge seals are pressed by the developing roller and elastically deform, preventing gaps from forming between the side edge seals and the developing roller, ensuring sealing performance.

[0017] A sixth aspect of the present disclosure is a developing device according to any one of the first to fifth aspects, wherein the plurality of fibers may be configured to transport the toner from the outside to the inside in the axial direction as they move from the upstream side to the downstream side in the rotation direction of the developing roller.

[0018] According to the above configuration, the toner can be easily sent inward in the axial direction in the side seal, and therefore the sealing performance of the side seal can also be easily improved. [Effects of the Invention]

[0019] According to one aspect of the present disclosure, a developing device can be realized that can suppress toner leakage even when the rotation speed of the developing roller is increased. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 2 is a front view of a developing device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a side view showing a configuration of a main part of the developing device. [Figure 3] (A) is an enlarged plan view showing the main configuration of the developing device, (B) is a cross-sectional view along line BB in Figure 3(A), and (C) is an enlarged plan view showing an example of the configuration of the side seal and lower seal included in the developing device. [Figure 4] 4A is a front view of the layer thickness regulating blade included in the developing device, (B) is an exploded perspective view showing the surface layer and side edge seal of the side seal attached to the layer thickness regulating blade, (C) is a perspective view of the side seal shown in Fig. 4A when viewed from the back side of the layer thickness regulating blade, and (D) is an enlarged cross-sectional view showing the relationship between the surface layer of the side seal, the side edge seal, and the rubber part when a cross section is taken in a direction perpendicular to the paper surface of Fig. 4A. [Figure 5] FIG. 2 is a perspective view showing the lower layer of the side seal. [Figure 6] (A) is a diagram illustrating a specific example of the movement of the surface and lower layers of the side seal when the developing roller included in the developing device is assembled, and (B) is a diagram illustrating a specific example of the movement of the toner on the surface layer of the side seal when the developing roller rotates. [Figure 7] 4 is a flowchart showing a method for assembling the developing device. DETAILED DESCRIPTION OF THE INVENTION

[0021] An embodiment of the present disclosure will be described below with reference to Figures 1 to 7. In this embodiment, a developing device 1 including a developing roller 3 that carries toner, which is an example of a developer, on its peripheral surface 3A will be described. The developing device 1 of this embodiment is installed in an image forming apparatus such as an electrophotographic printer including a laser printer or an LED printer.

[0022] [Overall configuration of developing device 1] Fig. 1 is a front view of a developing device 1 according to an embodiment of the present disclosure. Fig. 2 is a side view showing the main configuration of the developing device 1. In Fig. 1, the developing device 1 of this embodiment includes a developing frame 2, a developing roller 3, and a layer thickness regulating blade 4. The developing device 1 also includes a side seal 5, a lower seal 6, a lower side seal 8, and a side edge seal 9 as sealing members that prevent toner from leaking from the inside to the outside of the developing frame 2.

[0023] The developing frame 2 constitutes an outer container of the developing device 1 and houses the main components of the developing device 1 therein. The developing frame 2 rotatably supports the developing roller 3 by supporting the rotation shaft 3B of the developing roller 3. Referring to FIG. 2, the developing frame 2 rotatably supports the supply roller 7, whose axial direction is arranged parallel to the axial direction of the developing roller 3. In FIG. 2, the developing roller 3 and the supply roller 7 are each driven to rotate counterclockwise by a driving mechanism such as a motor (not shown).

[0024] The thickness-regulating blade 4 is provided on the developing frame 2 and has, for example, a blade main body 4A formed in a substantially L-shape and a rubber portion 4B that contacts the circumferential surface 3A of the developing roller 3. The blade main body 4A is an example of a blade that supports the rubber portion 4B and is made of, for example, metal. The rubber portion 4B is made of a rubber material such as silicone rubber or urethane rubber and regulates the thickness of the toner carried on the circumferential surface 3A of the developing roller 3 to a predetermined value. The thickness-regulating blade 4 is fixed to the developing frame 2 by, for example, screws such as bolts and / or fixing members such as double-sided tape.

[0025] The blade body 4A may be a metal plate pressed into an approximately L-shape to which a flat metal plate supporting the rubber part 4B is joined by welding or screwing, or it may be a single metal plate pressed into an approximately L-shape.

[0026] In the developing frame 2, a toner storage unit such as a toner cartridge or toner tank (not shown) that stores toner is detachably connected to the upper side of the supply roller 7, and toner from the toner storage unit is supplied onto the circumferential surface 3A of the developing roller 3 via the supply roller 7. At this time, the toner is frictionally charged, for example, to a positive polarity, between the supply roller 7 and the developing roller 3. The toner supplied onto the circumferential surface 3A of the developing roller 3 is further frictionally charged by the rubber portion 4B of the layer thickness regulating blade 4, and is regulated to a thin layer having the above-mentioned predetermined thickness and carried on the circumferential surface 3A.

[0027] The toner used in this embodiment is, for example, a positively charged, non-magnetic single-component toner. This single-component toner is, for example, a styrene-acrylic resin formed into a spherical shape by suspension polymerization, to which a well-known colorant such as carbon black and a charge control agent such as a quaternary ammonium salt are added. Furthermore, this single-component toner uses toner base particles with an average particle size of 5 μm to 10 μm, and silica, for example, is added as an external additive to the surface. Note that the use of fine toner base particles with an average particle size of 5 μm to 7 μm makes it possible to improve the image quality of printed matter after image formation processing in the image forming apparatus.

[0028] 1 and 2, the side seals 5 are disposed between the developer frame 2 and the axial ends of the developing roller 3 so as to contact the circumferential surface 3A of the developing roller 3. In other words, the side seals 5 are provided in contact with the developer frame 2 at both ends of the axial direction, which is the longitudinal direction of the circumferential surface 3A of the developing roller 3, thereby enhancing the sealing performance against the toner at each of the left and right ends of the developing roller 3 and suppressing leakage of the toner. As shown in FIG. 2, the side seals 5 include a surface layer 5A provided on the developing roller 3 side and a lower layer 5B provided on the developing frame 2 side and supporting the surface layer 5A.

[0029] 1 and 2, the lower seal 6 is provided on the developing frame 2 so as to extend in the axial direction, upstream of the layer thickness regulating blade 4 in the rotation direction of the developing roller 3, and is adapted to come into contact with the peripheral surface 3A of the developing roller 3. The lower seal 6 is made of a synthetic resin such as PET (polyethylene terephthalate), and is fixed to the developing frame 2 via fixing members such as double-sided tape or bolts (not shown). The lower seal 6 improves the sealing performance against toner in the lower portion of the developing roller 3, thereby suppressing leakage of the toner.

[0030] 2, the lower side seals 8 are provided between the axial ends of the lower seal 6 and the developing frame 2. That is, two lower side seals 8 are provided at the left and right axial ends of the developing roller 3, axially inward of the side seals 5, between the lower surface of the lower seal 6 and the surface of the developing frame 2.

[0031] [Main components of developing device 1] The configuration of the main parts of the developing device 1 of this embodiment will be described in detail with reference to Figures 3 to 5. Figure 3(A) is an enlarged plan view showing an example of the configuration of the main parts of the developing device 1, Figure 3(B) is a cross-sectional view taken along line BB in Figure 3(A), and Figure 3(C) is an enlarged plan view showing an example of the configuration of the side seal 5 and lower seal 6 included in the developing device 1. Figure 4(A) is a front view of the layer-thickness regulating blade 4 included in the developing device 1, Figure 4(B) is an exploded perspective view showing the surface layer 5A and side edge seal 9 of the side seal 5 attached to the layer-thickness regulating blade 4, Figure 4(C) is a perspective view of the side seal 5 shown in Figure 4(A) as seen from the back side of the layer-thickness regulating blade 4, and Figure 4(D) is an enlarged cross-sectional view showing the relationship between the surface layer 5A of the side seal 5, the side edge seal 9, and the rubber portion 4B when a cross section is taken in a direction perpendicular to the plane of Figure 4(A). FIG. 5 is a perspective view showing the lower layer 5B of the side seal 5. As shown in FIG.

[0032] Since the main configuration of the developing device 1 of this embodiment is substantially symmetrical in the left-right direction of Fig. 1, the following description will be made by illustrating, for example, the left side of Fig. 1. Also, in Fig. 3(A), the developing roller 3 is omitted from illustration in order to simplify the drawing.

[0033] As shown in Figure 3(A), the upper end of the surface layer 5A of the side seal 5, i.e., the downstream end in the rotation direction of the developing roller 3, is attached to the blade body 4A of the layer thickness regulating blade 4 with a side edge seal 9 interposed therebetween. Also, the lower end of the surface layer 5A of the side seal 5, i.e., the upstream end in the rotation direction of the developing roller 3, is provided so as to be movable relative to the lower layer 5B assembled to the developing frame 2. The developing roller 3 has its rotation shaft 3B rotatably supported by a bearing 2A provided in the developing frame 2, and is driven to rotate in a direction from the bottom to the top of Figure 3(A).

[0034] 3(A), the lower side seal 8 is configured, for example, in a rectangular shape, and is fixed to the developing frame 2 so as to support the axial end of the lower seal 6. In this way, the lower side seal 8 can support the axial end of the lower seal 6 on the developing frame 2, thereby preventing the axial end of the lower seal 6 from separating from the developing roller 3. As a result, the sealing performance of the lower seal 6 can be maintained.

[0035] The lower side seal 8 is made of an elastic material such as sponge, which allows the lower seal 6 to make elastic contact with the developing roller 3, ensuring the sealing performance of the lower seal 6 even when the rotation speed of the developing roller 3 is increased, and facilitating smooth rotation of the developing roller 3.

[0036] As shown in Fig. 3(B), the surface layer 5A of the side seal 5 includes a base sheet 5AA and a plurality of fibers 5AB implanted in the base sheet 5AA. The fibers 5AB come into contact with the peripheral surface 3A of the developing roller 3. Note that, in Fig. 3(B), the side edge seal 9 and other components are omitted for simplicity.

[0037] The base sheet 5AA is made of a flexible material such as cloth. The fibers 5AB are made of ultra-high molecular weight polyethylene, polyparaphenylene benzobisoxadol (PBO) fibers, etc. In the surface layer 5A, as will be described in detail later, the fibers 5AB are planted in a state of being aligned in a predetermined direction relative to the base sheet 5AA.

[0038] 3A, the surface layer 5A of the side seal 5 is attached to the blade main body 4A via the side edge seal 9 so that the downstream end in the rotation direction of the developing roller 3 is adjacent to one end of the rubber part 4B in the axial direction of the developing roller 3. In addition, the upstream end in the surface layer 5A of the side seal 5 in the rotation direction of the developing roller 3 is adjacent to one end of the lower seal 6 in the axial direction of the developing roller 3.

[0039] More specifically, as shown in Fig. 3(C), in the surface layer 5A of the side seal 5, the end surface 5AA1 of the base sheet 5AA faces the end surface 6A of the lower seal 6 in the axial direction of the developing roller 3. "Facing" here refers to a state in which the end surface 5AA1 and the end surface 6A are arranged side by side with a small space between them, as exemplified in Fig. 3(C), or a state in which the end surface 5AA1 and the end surface 6A are in contact with each other without such a space between them. "Facing" here does not include a state in which one of the end surface 5AA1 and the end surface 6A overlaps the other in the thickness direction.

[0040] In addition, in the surface layer 5A of the side seal 5, some of the fibers 5AB protrude from the end surface 5AA1 of the base sheet 5AA toward the end surface 6A of the lower seal 6 and overlap with the end of the lower seal 6, as illustrated in Figure 3(C).

[0041] As shown in FIG. 4(A), the blade body 4A of the layer thickness regulating blade 4 is configured to be assembled to the developing frame 2 with the surface layer 5A of the side seal 5 attached to each end in the left and right directions of the figure.

[0042] 4(B), the side edge seal 9 is fixed to the blade body 4A via, for example, double-sided tape T1. The side edge seal 9 is made of, for example, an elastic material such as sponge, and elastically supports the surface layer 5A of the side seal 5.

[0043] As shown in FIG. 4(B), the surface layer 5A of the side seal 5 includes a portion 5A1 and a portion 5A2. The portion 5A1 has a rectangular base sheet 5AA and fibers 5AB that are arranged along the circumferential surface 3A of the developing roller 3. The portion 5A2 is made of fibers 5AB that protrude from the portion 5A1 toward the lower seal 6. The portion 5A1 is configured to be longer than the length of the side edge seal 9. The surface layer 5A is fixed to the side edge seal 9 via, for example, double-sided tape T2.

[0044] As shown by "L" in FIG. 4(C), the double-sided tape T2 is attached to the side edge seal 9 in a state where it protrudes from the blade main body 4A by a predetermined distance, for example, about 6 mm. The surface layer 5A of the side seal 5 is fixed to the blade main body 4A in a state where it protrudes from the blade main body 4A by a predetermined distance, for example, about 15 mm. When the layer thickness regulating blade 4 is assembled to the developing frame 2, the surface layer 5A of the side seal 5 is fixed to the lower layer 5B of the side seal 5 via the protruding portion of the double-sided tape T2. Furthermore, the protruding portion of the surface layer 5A, including the upstream end portion, other than the protruding portion of the double-sided tape T2, is assembled movably to the lower layer 5B.

[0045] As shown in FIG. 4(D), in the layer thickness regulating blade 4, the side edge seal 9 is fixed to the blade body 4A so that its axial end face faces the axial end face of the rubber portion 4B and is adjacent to the rubber portion 4B, and the side edge seal 9 is provided on the developing frame 2. This makes it possible for the side edge seal 9 to prevent toner leakage from the rubber portion 4B. Furthermore, because the side edge seal 9 is made of an elastic material, even if the rubber portion 4B wears, the side edge seal 9 is pressed by the developing roller 3 and elastically deforms, preventing a gap from forming between the side edge seal 9 and the developing roller 3. This ensures the sealing performance of the side edge seal 9.

[0046] Furthermore, when the layer thickness regulating blade 4 is assembled to the developing frame 2, as shown in Figure 4(D), the side edge seal 9 is positioned on the blade body 4A so that its end face faces the end face of the base sheet 5AA of the surface layer 5A of the side seal 5.

[0047] 5, the lower layer 5B of the side seal 5 is integrally formed using an elastic material such as a porous sponge. The lower layer 5B is attached to the developer frame 2 by fitting into a mounting portion (not shown), such as a recess, provided at a predetermined position on the developer frame 2. The lower layer 5B also has a non-through recess included in the porous structure on the surface facing the developing roller 3, and even if toner leaks out, the recess can retain the toner, improving the sealing performance of the side seal 5.

[0048] Furthermore, in the side seal 5, the surface layer 5A is elastically supported by the lower layer 5B, so the side seal 5 can elastically contact the axial end of the developing roller 3. As a result, in the developing device 1 of this embodiment, even when the rotation speed of the developing roller 3 is increased, the developing roller 3 can easily rotate smoothly while ensuring the sealing performance of the side seal 5.

[0049] [Example of side seal 5 operation] Figure 6(A) is a diagram illustrating a specific example of the operation of the surface layer 5A and lower layer 5B of the side seal 5 when the developing roller 3 included in the developing device 1 is assembled, and Figure 6(B) is a diagram illustrating a specific example of the operation of the toner TN on the surface layer 5A of the side seal 5 when the developing roller 3 rotates.

[0050] As shown in FIG. 6A, when the developing roller 3 is assembled to the developing frame 2 while being moved in the direction of arrow P, the peripheral surface 3A of the developing roller 3 abuts against the surface layer 5A of the side seal 5 while applying a pressing force in the direction P. At this time, the upstream end of the surface layer 5A is not fixed to the lower layer 5B and is movable relative to the lower layer 5B, so it moves in response to the pressing force as shown by arrow M in the figure. As a result, the occurrence of deformation such as wrinkles in the surface layer 5A and lower layer 5B of the side seal 5 is suppressed, and deterioration of the sealing performance of the side seal 5 due to deformation can be suppressed.

[0051] As shown in Figure 6(B), in the surface layer 5A of the side seal 5, the fibers 5AB are grafted onto the base sheet 5AA shown in Figure 4(B) with the fibers 5AB aligned diagonally upward and to the right of the figure. Therefore, even if the toner TN is superimposed on the fibers 5AB, when the developing roller 3 rotates in the direction of arrow T in the figure, a force in the direction of arrow K in the figure acts on the toner TN from the fibers 5AB as the developing roller 3 rotates. As a result, the toner TN that has leaked onto the fibers 5AB from the inside of the developing frame 2 is returned to the inside of the developing frame 2 as the developing roller 3 rotates.

[0052] In this way, in the developing device 1 of this embodiment, the multiple fibers 5AB are configured to send the toner TN from the outside to the inside in the axial direction as they move from the upstream side to the downstream side in the rotation direction of the developing roller 3. As a result, in the developing device 1 of this embodiment, the toner TN can be easily sent to the inside in the axial direction in the side seal 5, and therefore the sealing performance of the side seal 5 can also be easily improved.

[0053] [Method of assembling the main components of the developing device 1] Fig. 7 is a flowchart showing a method for assembling the developing device 1. Fig. 7 mainly explains a method for assembling the main components of the developing device 1 of this embodiment.

[0054] 7, in step S1, the supply roller 7 is assembled to a predetermined position on the developing frame 2. Next, in step S2, the lower side seals 8 are attached to the developing frame 2 in correspondence with the positions of the left and right ends of the axial direction of the developing roller 3. That is, in step S2, prior to the attaching step described below, a lower side seal attaching step is performed in which the lower side seals 8 are attached so as to be positioned between the axial ends of the lower seal 6 and the developing frame 2.

[0055] Subsequently, in step S3, the lower layer 5B of the side seal 5 is assembled to the mounting portion of the developing frame 2. Next, in step S4, the lower seal 6 is attached to the developing frame 2 so as to cover the left and right lower side seals 8. That is, in step S4, a lower seal attaching step is performed in which the lower seal 6 is attached onto the lower side seals 8 before the attaching step described below.

[0056] Subsequently, in step S5, the layer thickness regulating blade 4 is assembled. Specifically, the double-sided tape T1, side edge seal 9, double-sided tape T2, and surface layer 5A of the side seal 5 shown in Fig. 4(B) are attached to the left and right ends of the blade main body 4A having the rubber portion 4B. That is, in step S5, an attachment process is performed in which the surface layer 5A is attached to the blade main body 4A of the layer thickness regulating blade 4 so that the downstream end of the surface layer 5A in the rotation direction is adjacent to one end of the rubber portion 4B in the axial direction.

[0057] In addition, in the bonding process, as shown in Figure 3(A), the downstream end of the surface layer 5A is bonded to the blade body 4A with the axial end face facing the axial end face of the rubber portion 4B, with the side edge seal 9 adjacent to the rubber portion 4B interposed therebetween.

[0058] Subsequently, in step S6, the layer thickness regulating blade 4 is assembled. Specifically, the layer thickness regulating blade 4 assembled in step S5 is fixed to the developing frame 2 by the fixing member. In this step S6, a first assembly process and a second assembly process are performed sequentially. In the first assembly process, the layer thickness regulating blade 4 is assembled to the developing frame 2. In the second assembly process, the surface layer 5A of the side seal 5 is assembled to the developing frame 2 so that the upstream end of the surface layer 5A in the rotational direction of the surface layer 5A is adjacent to one end of the lower seal 6 in the axial direction.

[0059] In the second assembling step, the surface layer 5A is assembled to the developing frame 2 so that the end surface 5AA1 of the base sheet 5AA faces the end surface 6A of the lower seal 6 in the axial direction, as shown in FIG. 3(C).

[0060] Furthermore, in the second assembly process, as shown in Figure 3(C), the surface layer 5A is assembled to the developing frame 2 so that some of the fibers 5AB protrude from the end surface 5AA1 of the base sheet 5AA toward the end surface 6A of the lower seal 6 and overlap with the end of the lower seal 6.

[0061] Furthermore, in the second assembling step, the upstream end of the surface layer 5A is movably attached to the developing frame 2 as shown in FIG. 6(A).

[0062] As described above, in the method for assembling the developing device 1 of this embodiment, the pasting step is performed before the first assembly step, and the second assembly step is performed after the first assembly step. As a result, in the method for assembling the developing device 1 of this embodiment, even when assembling a long side seal 5 that is integrally formed with the developing frame 2 and has a surface layer 5A having a base sheet 5AA with a plurality of fibers 5AB implanted therein, the side seal 5 can be easily and accurately assembled. As a result, in this embodiment, it is possible to easily assemble the developing device 1 that can suppress toner leakage even when the rotation speed of the developing roller 3 is increased.

[0063] Subsequently, in step S7, the developing roller 3 is assembled to the developing frame 2, completing the assembly of the main components of the developing device 1 of this embodiment.

[0064] As described above, in the developing device 1 of this embodiment, the end surface 5AA1 of the base sheet 5AA and the end surface 6A of the lower seal 6 face each other in the axial direction of the developing roller 3. Therefore, the base sheet 5AA and the lower seal 6 can be provided without creating a step due to one of the base sheet 5AA and the lower seal 6 overlapping the other. This eliminates gaps due to the step, thereby reliably preventing toner leakage through the gap. Furthermore, because some of the fibers 5AB overlap the end of the lower seal 6, even if a space is created between the end surface 5AA1 of the base sheet 5AA and the end surface 6A of the lower seal 6, toner accumulation in the space and toner leakage from the space are significantly reduced. As a result, the developing device 1 of this embodiment can prevent toner leakage even when the rotation speed of the developing roller 3 is increased. Furthermore, even when a highly fluid toner, i.e., a toner having fine toner base particles with a small average particle size, is used to improve the image quality of printed materials or increase the rotation speed of the developing roller 3, the developing device 1 of this embodiment can prevent toner leakage.

[0065] If the lower seal 6 is placed on top of the side seal 5, when the developing roller 3 is assembled, the thickness of the lower seal 6 will push the end of the side seal 5 away from the surface of the developing roller 3, making it easier for toner to leak. On the other hand, if the side seal 5 is placed on top of the lower seal 6, when the developing roller 3 is assembled, the thickness of the side seal 5 will push the end of the lower seal 6 away from the surface of the developing roller 3, making it easier for toner to leak. By not placing the side seal 5 and the lower seal 6 on top of each other, as in the product of this embodiment, the above problem does not occur.

[0066] Furthermore, when the side seal 5 and the lower seal 6 are assembled so that they do not overlap, a small space may be formed between them, but this space is blocked by the fibers 5AB of the surface layer 5A of the side seal 5, so toner does not leak out from the space.

[0067] Furthermore, the developing device 1 of this embodiment includes the surface layer 5A having the base sheet 5AA in which the plurality of fibers 5AB are implanted, and uses the integrally formed long side seals 5, which easily improves the sealing performance of the side seals 5. As a result, the developing device 1 of this embodiment can prevent toner leakage even when the rotation speed of the developing roller 3 is increased.

[0068] In the above explanation, an example is given of the present disclosure being applied to a developing device, but the present disclosure is not limited to this, and for example, the present disclosure can also be applied to a developing cartridge that is configured so that a user can replace it as needed from an image forming device, etc.

[0069] [Additional information] The present disclosure includes an invention relating to a developing device comprising: a developing roller that carries toner; a developing frame that rotatably supports the developing roller; a layer thickness regulating blade that is provided on the developing frame and has a rubber portion that contacts the peripheral surface of the developing roller and a blade that supports the rubber portion; a side seal that is arranged between the developing frame and an axial end of the developing roller so as to contact the peripheral surface of the developing roller; and a lower seal that is provided on the developing frame upstream of the rotational direction of the developing roller relative to the layer thickness regulating blade and extends in the axial direction, and contacts the peripheral surface of the developing roller, wherein the side seal has a surface layer that has a plurality of fibers that contact the peripheral surface of the developing roller and a base sheet in which the plurality of fibers are implanted, and in the side seal, an end face of the base sheet faces an end face of the lower seal in the axial direction, and some of the plurality of fibers protrude from the end face of the base sheet toward the end face of the lower seal and overlap with the end of the lower seal.

[0070] According to the above configuration, the end face of the base sheet and the end face of the lower seal face each other in the axial direction of the developing roller. Therefore, the base sheet and the lower seal can be provided without creating a step due to one of them overlapping the other. This eliminates the formation of a gap due to the step, thereby reliably preventing toner leakage through the gap. Furthermore, because some of the multiple fibers overlap the end face of the lower seal, even if a space is created between the end face of the base sheet and the end face of the lower seal, toner accumulation in the space and toner leakage from the space are significantly reduced. As a result, toner leakage can be reduced even when the rotation speed of the developing roller is increased.

[0071] Furthermore, the present disclosure provides a developing roller that carries toner, a developing frame that rotatably supports the developing roller, a layer thickness regulating blade that is provided on the developing frame and has a rubber portion that contacts the circumferential surface of the developing roller and a blade that supports the rubber portion, a side seal that is disposed between the developing frame and an end of the developing roller in the axial direction so as to contact the circumferential surface of the developing roller, and has a surface layer that has a plurality of fibers that contact the circumferential surface of the developing roller and a base sheet in which the plurality of fibers are implanted, and a developing roller that extends in the axial direction, upstream of the layer thickness regulating blade in the rotation direction of the developing roller. The invention includes an invention relating to a method for assembling a developing device that includes a lower seal that is attached to a frame and contacts the peripheral surface of the developing roller, the method including: a bonding step for bonding the surface layer of the layer thickness regulating blade to the blade so that the downstream end of the surface layer in the rotational direction is adjacent to one end of the rubber portion in the axial direction; a first assembly step for assembling the layer thickness regulating blade to the developing frame; and a second assembly step for assembling the surface layer to the developing frame so that the upstream end of the surface layer in the rotational direction is adjacent to one end of the lower seal in the axial direction.

[0072] According to the above configuration, the pasting process is performed before the first assembling process, and the second assembling process is performed after the first assembling process. This allows the side seal to be easily and accurately assembled to the developing frame, even when the long side seal has a surface layer with a base sheet having multiple fibers woven therein and is integrally formed with the developing frame. As a result, it is possible to easily assemble a developing device that can suppress toner leakage even when the rotation speed of the developing roller is increased.

[0073] In the method for assembling the developing device, in the second assembling step, the surface layer may be assembled to the developing frame so that an end face of the base sheet faces an end face of the lower seal in the axial direction.

[0074] According to the above configuration, the end face of the base sheet and the end face of the lower seal face each other in the axial direction of the developing roller, so that the base sheet and the lower seal can be provided without creating a step caused by one of the base sheet and the lower seal overlapping the other, thereby preventing a gap caused by the step and reliably preventing toner leakage through the gap.

[0075] Furthermore, in the above-mentioned developing device assembling method, in the second assembly process, the surface layer may be assembled to the developing frame so that some of the fibers protrude from the end face of the base sheet toward the end face of the lower seal and overlap with the end of the lower seal.

[0076] According to the above configuration, because some of the fibers overlap with the end of the lower seal, even if a space is formed between the end face of the base sheet and the end face of the lower seal, toner accumulation in the space and toner leakage from the space can be significantly suppressed, and as a result, toner leakage can be suppressed even when the rotation speed of the developing roller is increased.

[0077] In addition, in the above-mentioned method for assembling the developing device, before the attaching step, a lower side seal attaching step of attaching a lower side seal so that it is positioned between the axial end of the lower seal and the developing frame, and a lower seal attaching step of attaching the lower seal onto the lower side seal may be carried out sequentially.

[0078] According to the above configuration, the lower side seal can support the axial end of the lower seal on the developing frame, thereby reliably preventing the axial end of the lower seal from separating from the developing roller.

[0079] Furthermore, in the above-described method for assembling the developing device, in the attaching step, the downstream end portion may be attached to the blade with a side edge seal adjacent to the rubber portion interposed therebetween, with the axial end surface facing the axial end surface of the rubber portion.

[0080] With this configuration, the side edge seals can prevent toner leakage from the rubber portion. Even if the rubber portion wears, the side edge seals are pressed by the developing roller and elastically deform, preventing gaps from forming between the side edge seals and the developing roller, ensuring sealing performance.

[0081] In the method for assembling the developing device, the upstream end may be movably assembled to the developing frame in the second assembly step.

[0082] According to the above configuration, the upstream end of the surface layer of the side seal is movably attached to the developing frame, so that when the developing roller is attached to the developing frame, deformation such as wrinkles on the surface layer of the side seal due to pressure from the developing roller side can be suppressed, and the sealing properties of the side seal can be prevented from decreasing.

[0083] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Configurations obtained by appropriately combining the technical means disclosed in the respective embodiments are also included in the technical scope of the present disclosure. [Explanation of symbols]

[0084] 1. Developing device 2 Developing Frame 3 Developing roller 4-layer thickness regulation blade 4A Blade Body 4B rubber part 5 Side seal 5A Surface layer 5AA base sheet 5AA1 End face 5AB Fiber 5B Lower layer 6 Lower Seal 8 Lower side seal 9 Side edge seal TN Toner

Claims

1. a developing roller that carries toner; a developing frame that rotatably supports the developing roller; a layer thickness regulating blade provided on the developing frame and having a rubber portion that contacts the peripheral surface of the developing roller and a blade that supports the rubber portion; a side seal disposed between the developing frame and an end of the developing roller in the axial direction so as to come into contact with the peripheral surface of the developing roller; a side edge seal formed using an elastic body and provided on the developing frame so as to be adjacent to the rubber portion with an end surface in the axial direction facing the end surface in the axial direction of the rubber portion; a lower seal provided on the developing frame to extend in the axial direction and upstream of the layer thickness regulating blade in the rotation direction of the developing roller, and in contact with the circumferential surface of the developing roller; The side seal is a surface layer having a plurality of fibers that contact the peripheral surface of the developing roller and a base sheet in which the plurality of fibers are implanted; and a lower layer that is attached to the developing frame and supports the surface layer, the surface layer is attached to the blade with the side edge seal interposed therebetween so that a downstream end portion in the rotation direction is adjacent to one end portion of the rubber portion in the axial direction, an upstream end of the surface layer in the rotational direction adjacent to one end of the lower seal in the axial direction; In the surface layer, some of the plurality of fibers protrude inward in the axial direction from an end surface of the base sheet, a downstream end of the surface layer in the axial direction attached to the side edge seal with double-sided tape; the double-sided tape has a protruding portion that protrudes upstream of the side edge seal in the axial direction, The surface layer is fixed to the lower layer via the protruding portion.

2. a developing roller that carries toner; a developing frame that rotatably supports the developing roller; a layer thickness regulating blade provided on the developing frame and having a rubber portion that contacts the peripheral surface of the developing roller and a blade that supports the rubber portion; a side seal disposed between the developing frame and an end of the developing roller in the axial direction so as to come into contact with the peripheral surface of the developing roller; a side edge seal formed using an elastic body and provided on the developing frame so as to be adjacent to the rubber portion with an end surface in the axial direction facing the end surface in the axial direction of the rubber portion; a lower seal provided on the developing frame to extend in the axial direction and upstream of the layer thickness regulating blade in the rotation direction of the developing roller, and in contact with the circumferential surface of the developing roller; The side seal is a surface layer having a plurality of fibers that contact the peripheral surface of the developing roller and a base sheet in which the plurality of fibers are implanted; the surface layer is attached to the blade with the side edge seal interposed therebetween so that a downstream end portion in the rotation direction is adjacent to one end portion of the rubber portion in the axial direction, an upstream end of the surface layer in the rotational direction adjacent to one end of the lower seal in the axial direction; In the surface layer, some of the plurality of fibers protrude inward in the axial direction from an end surface of the base sheet, The developing device has an upstream end of the surface layer in the rotation direction movably attached to the developing frame.

3. 3. The developing device according to claim 1, wherein the portion of the fibers protruding inward in the axial direction from the end face of the base sheet is disposed between the rubber portion and the lower seal in the rotational direction.

4. a lower side seal formed of an elastic material and provided between an end of the lower seal in the axial direction and the developing frame, 4. The developing device according to claim 1, wherein the lower side seal is attached to the developing frame, and the lower seal is attached onto the lower side seal.

5. 2. The developing device according to claim 1, wherein the lower layer is made of an elastic material.

6. 6. The developing device according to claim 1, wherein the plurality of fibers are configured to transport the toner from the outside to the inside in the axial direction as they move from the upstream side to the downstream side in the rotation direction of the developing roller.

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