JP2018151559A - Development apparatus, process unit, image forming apparatus, and method of manufacturing development apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a development apparatus which can prevent an abnormal image from being formed due to leakage of filler.SOLUTION: A development apparatus includes: a regulation member having a regulation unit with one end held by an attachment unit and the other end extended toward a developing roller; sponge 37 arranged between the attachment unit and a developing case 30 to fill a gap; and end seal 38 arranged in contact with a circumferential surface of the developing roller on an axial end side, to fill a gap between the developing roller and the developing case 30. A gap W2 is formed between the sponge 37 and the end seal 38. The gap W2 is filled with silicon sealant 39 for filling the gap W2. The developing case 30 includes a convex body 40 which is extended from the side of the sponge 37 toward the end seal 38 in the gap W2, to be in contact with at least one of the sponge 37 and the end seal 38, and projecting with respect to a filling space to be filled with the silicon sealant 39.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a developing device, a process unit including the developing device, an image forming apparatus including the developing device, and a method for manufacturing the developing device.

  The developing device carries a developer on its surface and supplies it to a latent image carrier such as a photoconductor, or a regulation that regulates the layer thickness of the developer on the surface of the developer carrier to a certain level or less. A member, a housing of a developing device for holding these members, and the like.

  In order to prevent the developer from leaking to the outside of the developing device, it is generally provided that a seal member such as a sponge is provided between the developer carrier or the regulating member and the housing, and the gap is sealed. Has been made.

  For example, in the developing device of Patent Document 1 (Japanese Patent Application Laid-Open No. 2014-174462), an end seal member is attached to the developing case at the end in the longitudinal direction of the developing roller. To prevent toner leakage.

  Further, in this developing device, in order to relieve the contact pressure between the regulating blade and the developing roller, the regulating blade is not fixed to the developing case on the end side in the longitudinal direction of the developing roller but is set as a free end. Then, a silicone sealant is applied to a gap generated between the free end of the regulating blade and the developing case, thereby preventing toner leakage from this portion.

  Due to component tolerances, assembly errors, etc., an error occurs in the gap between the housing of the developing device and the developer carrier or the regulating member. For this reason, as in Patent Document 1, in order to apply a filler such as silicon sealant and close the gap, it is necessary to set a sufficient application amount in consideration of the above-described error.

  On the other hand, however, if the amount of filler applied becomes too large, the filler overflowing from the gaps will leak and mix with the developer, causing problems such as abnormal images.

  Under such circumstances, an object of the present invention is to provide a developing device that can prevent formation of an abnormal image due to the outflow of the filler.

  In order to solve the above-described problems, the present invention provides a housing, a developer carrier that is rotatably provided on the housing and carries a developer on a surface thereof, and an attachment portion that is attached to the housing. A regulating portion that holds one end of the developer on the surface of the developer carrying body by holding the one end side of the mounting portion and extending the other end to the developer carrying body. A first sealing member that is provided between the mounting portion and the housing and fills the gap, and is provided in contact with the peripheral surface on the axial end portion side of the developer carrier. And a second seal member that fills a gap between the developer carrying member and the housing in the portion, wherein a gap between the seals is provided between the first seal member and the second seal member. A gap is provided, and a filler for filling the gap between the seals is provided between the seal gaps. The casing is filled and extends in the gap between the seals from the first seal member side to the second seal member side, and is at least one of the first seal member and the second seal member A convex body provided so as to protrude with respect to the filling space filled with the filler, the convex body being in the axial center of the developer carrier more than the filling space and the filling space It is characterized by partitioning the side space.

  In the present invention, the convex body provided between the seal gaps can block the flow of the filler from the filling space to the inner side in the axial direction of the developer carrier, and an abnormal image caused by the outflow of the filler. Can be prevented.

1 is a schematic configuration diagram of an image forming apparatus. FIG. 2 is a schematic cross-sectional view illustrating a developing device and a peripheral structure thereof. It is a perspective view of the axial direction edge part side of a developing device. It is sectional drawing of a developing device. It is A1-A1 sectional drawing of FIG. It is a perspective view which shows the attachment part of a developing roller and a control blade. It is a perspective view explaining the assembly procedure of a developing device. FIG. 5 is a perspective view showing a mounting portion of a developing roller and a regulating blade of the developing device of the present embodiment. It is a perspective view of the developing device of this embodiment. It is A2-A2 sectional drawing of FIG. It is sectional drawing of the image development apparatus of different embodiment.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified or abbreviate | omitted suitably.

  In the center of the color image forming apparatus 1 shown in FIG. 1, an image forming unit 2 in which four process units 9Y, 9M, 9C, 9Bk are detachably provided is arranged. Each process unit 9Y, 9M, 9C, 9Bk contains developers of different colors of yellow (Y), magenta (M), cyan (C), and black (Bk) corresponding to the color separation components of the color image. The configuration is the same except that.

  Specifically, each process unit 9 includes a photosensitive member (latent image carrier) 10 which is a drum-like rotating member capable of carrying toner as a developer on the surface, and the surface of the photosensitive member 10 is uniformly charged. And a developing device 12 having a developing roller (developer carrying member) 13 for supplying toner to the surface of the photoreceptor 10. The photoreceptor 10 is formed by applying a photosensitive layer to an aluminum base tube.

  An exposure unit 3 is disposed above the process unit 9. The exposure unit 3 is configured to emit laser light based on the image data.

  A transfer unit 4 is disposed immediately below the image forming unit 2. The transfer unit 4 has an endless intermediate transfer belt 16 that is stretched around the drive roller 14 and the driven roller 15 so as to be able to run around, and a position facing the photoreceptor 10 of each process unit 9 with the intermediate transfer belt 16 in between. The primary transfer roller 17 and the like arranged in Each primary transfer roller 17 presses the inner peripheral surface of the intermediate transfer belt 16 at each position, and a primary transfer nip is formed at a place where the pressed portion of the intermediate transfer belt 16 and each photoconductor 10 are in contact with each other. ing.

  A secondary transfer roller 18 is disposed at a position opposite to the drive roller 14 of the intermediate transfer belt 16 and the drive roller 14 across the intermediate transfer belt 16. The secondary transfer roller 18 presses the outer peripheral surface of the intermediate transfer belt 16, and a secondary transfer nip is formed at a location where the secondary transfer roller 18 and the intermediate transfer belt 16 are in contact with each other.

  The paper feed unit 5 is located below the image forming apparatus 1 and includes a paper feed cassette 19 that stores paper P as a recording medium, a paper feed roller 20 that carries the paper P out of the paper feed cassette 19, and the like. ing.

  The conveyance path 6 is a conveyance path that conveys the paper P carried out from the paper feeding unit 5, and the conveyance roller pair is located in the middle of the conveyance path 6 until it reaches the paper discharge unit 8 described later in addition to the pair of registration rollers 21. Are appropriately arranged.

  The fixing unit 7 includes a fixing roller 22 that is heated by a heating source, a pressure roller 23 that can press the fixing roller 22, and the like.

  The paper discharge unit 8 is provided on the most downstream side of the conveyance path 6 of the image forming apparatus 1. The paper discharge unit 8 is provided with a pair of paper discharge rollers 24 for discharging the paper P to the outside and a paper discharge tray 25 for stocking the discharged paper P.

  The basic operation of the image forming apparatus 1 will be described below with reference to FIG.

  When the image forming operation is started in the image forming apparatus 1, an electrostatic latent image is formed on the surface of the photoconductor 10 of each process unit 9Y, 9C, 9M, 9Bk. The image information exposed to each photoconductor 10 by the exposure unit 3 is single-color image information obtained by separating a desired full-color image into color information of yellow, cyan, magenta, and black. An electrostatic latent image is formed on each photoconductor 10, and toner stored in each developing device 12 is supplied to the photoconductor 10 by a drum-shaped developing roller 13, whereby the electrostatic latent image is visualized. A visible image is formed as a toner image (developer image).

  In the transfer unit 4, the intermediate transfer belt 16 is driven to run in the direction of arrow A in the figure by the rotational drive of the drive roller 14. Further, each primary transfer roller 17 is applied with a constant voltage or a constant current-controlled voltage having a polarity opposite to the charging polarity of the toner. As a result, a transfer electric field is formed in the primary transfer nip, and the toner images formed on the respective photoconductors 10 are sequentially superimposed and transferred on the intermediate transfer belt 16 in the primary transfer nip.

  On the other hand, when the image forming operation is started, the sheet P stored in the sheet feeding cassette 19 is moved to the transport path 6 by rotating the sheet feeding roller 20 of the sheet feeding unit 5 below the image forming apparatus 1. Sent out. The sheet P sent to the conveyance path 6 is timed by the registration roller 21 and is sent to the secondary transfer nip between the secondary transfer roller 18 and the drive roller 14. At this time, a transfer voltage having a polarity opposite to the toner charging polarity of the toner image on the intermediate transfer belt 16 is applied, and a transfer electric field is formed in the secondary transfer nip. The toner images on the intermediate transfer belt 16 are collectively transferred onto the paper P by the transfer electric field formed in the secondary transfer nip.

  The sheet P on which the toner image is transferred is conveyed to the fixing unit 7, and the sheet P is heated and pressed by the fixing roller 22 and the pressure roller 23, and the toner image is fixed on the sheet P. Then, the paper P on which the toner image is fixed is separated from the fixing roller 22, transported by a pair of transport rollers, and discharged to the paper discharge tray 25 by the paper discharge roller 24 in the paper discharge unit 8.

  The above description is an image forming operation when a full color image is formed on the paper P. A single color image can be formed using any one of the four process units 9Y, 9C, 9M, and 9Bk. It is also possible to form two or three color images using two or three process units 9.

Next, a more detailed configuration of the developing device 12 will be described.
As shown in FIG. 2, the developing device 12 includes a developing case 30 as a housing of the developing device, a first screw 31 and a second screw 32 that convey toner, a supply roller 33 as a developer supply member, A developing roller 13 and a developing blade 34 as a regulating member are provided.

The developing roller 13 is composed of a metal core and conductive rubber disposed on the outer periphery of the core. In this embodiment, the outer diameter of the metal core is set to Φ6, the outer periphery of the conductive rubber is set to Φ12, and the rubber hardness Hs75. The conductive rubber has a volume resistance adjusted to about 10 ⁵ to 10 ⁷ Ω. As the conductive rubber, for example, conductive urethane rubber or silicone rubber can be generally used. The developing roller 13 is rotatably installed in the developing case 30 and rotates in the clockwise direction of FIG. 2 by a printing operation to convey the toner held on the surface to a position facing the photoreceptor 10.

  As the supply roller 33, a sponge roller or the like is generally used. As the sponge roller, it is appropriate that the foamed polyurethane mixed with carbon and made semiconductive is attached to the outer periphery of a metal core. In this embodiment, the outer diameter of the metal core is set to φ6, and the outer diameter of the sponge portion is set to φ12. The supply roller 33 is in contact with the developing roller 13. The nip portion formed by contact between the supply roller 33 and the developing roller 13 can be set to about 1 mm to 3 mm, and is set to 2 mm in this embodiment. Further, the supply roller 33 can efficiently supply the toner in the developing case 30 to the surface layer of the developing roller 13 by rotating in the counter direction (the clockwise direction in FIG. 2) with respect to the developing roller 13. In this embodiment, a good toner supply function is ensured by setting the rotation speed ratio between the developing roller 13 and the supply roller 33 to 1.

  The developing blade 34 is brought into contact with the developing roller 13 at a predetermined pressure at its end side to form a nip portion. Thereby, the thickness of the toner layer formed on the surface of the developing roller 13 can be regulated to be equal to or less than a certain level and uniformized. In the present embodiment, the developing blade 34 is made of a SUS material having a thickness of 0.1 mm, and the calculated contact pressure obtained from the bending calculation formula is set to 45 N / m. Further, the nip portion was set at a position 0.2 mm from the tip of the developing blade 34, and the length (free length) from the holding end portion to the free end of the developing blade 34 was set to 14 mm. A thin layer of toner can be formed.

  Inside the developing case 30, a first toner containing portion 30b for containing toner and a second toner containing portion 30c are provided.

  The first toner storage portion 30b and the second toner storage portion 30c are partitioned by a partition member 35 and communicate with each other via a communication port 35a. Thus, by dividing the toner container in the developing case 30 by the partition member 35, it is possible to suppress the toner powder pressure from being concentrated on the supply roller 33 and causing a large load.

  A first screw 31 is provided in the first toner containing portion 30b, and a second screw 32 is provided in the second toner containing portion 30c. By these screws, the toner in the respective storage units is conveyed. The toner in each storage unit is transported through the storage unit by each screw, and also travels between the storage units via the communication port 35 a and circulates in the developing case 30.

  The second toner container 30c is provided with an opening 30c1 that opens toward the photoreceptor 10, and toner leakage from the developing roller 13, the developing blade 34, and an opening 30c1 described later is provided in the opening 30c1. A sealing member or the like for closing the door is provided.

  A toner cartridge 50 is provided above the developing case 30. The toner cartridge 50 is connected to the developing case 30 via the replenishing ports 30a and 50a, and is detachably attached to the developing case 30. The toner cartridge 50 is provided with a stirring member 51 that stirs the toner in the toner cartridge 50. Note that the configurations of the developing device 12, the photosensitive member 10, and the toner cartridge 50 are not limited to the above, and may be configured such that they are integrally provided.

  The developing case 30 is provided with a toner remaining amount detecting mechanism that detects the remaining amount of toner in the developing case 30. When the toner remaining amount detection mechanism detects that the amount of toner in the developing case 30 has become below a certain level, the toner cartridge 50 is driven, and the toner in the toner cartridge 50 passes through the replenishing ports 50a and 30a. The toner is supplied to 30 toner storage units.

  Next, a specific configuration of the developing blade 34 and a mounting structure thereof will be described with reference to FIGS. In the following description, the axial direction of the developing roller is also simply referred to as the axial direction. Further, the axially central side of the developing roller is referred to as “axially inner side”, and the axially end portion side of the developing roller is referred to as “axially outer side”.

  As shown in FIG. 3, the developing blade 34 is in contact with the developing roller 13, holds a regulating portion 34 a that regulates the thickness of the toner layer on the surface of the developing roller 13 to a certain level, and a regulating portion 34 a. It consists of a mounting part 34b to be mounted.

  By inserting the positioning boss 30 d provided in the developing case 30 into the positioning hole 34 b 1, the mounting portion 34 b is positioned with respect to the developing case 30. In this state, as shown in FIG. 4, the mounting portion 34 b is fixed to the developing case 30 by the screw 36 being fastened to the fastening boss 30 e via the fixing hole 34 b 2 of the mounting portion 34 b.

  The restricting portion 34a is formed of a thin metal plate and abuts against the developing roller 13 in the axial direction. As shown in FIG. 5, the regulating portion 34 a has one end fixed to the mounting portion 34 b and is in contact with the developing roller 13 with the other end being a free end. As a method for fixing the restricting portion 34a to the mounting portion 34b, a necessary method such as welding, caulking, screwing, or the like can be selected as appropriate.

  With the developing blade 34 attached to the developing case 30, the section between the attaching portion 34b of the developing blade 34 and the developing case 30 is substantially L-shaped along the shape of the opposing portion of the developing case 30 and the attaching portion 34b. Shaped gaps are formed. In order to fill this gap and prevent the toner from flowing out of the developing device, a sponge 37 as a first seal member is provided between the developing case 30 and the mounting portion 34b.

  The sponge 37 is affixed to the mounting portion 34b of the developing blade 34 in advance. In this state, the sponge 37 has a substantially L-shaped cross section along the outer surface shape of the mounting portion 34b. Then, by assembling the developing blade 34 to the developing case 30, the sponge 37 is sandwiched between the developing case 30 and the attaching portion 34 b and is compressed, and the gap between the developing case 30 and the attaching portion 34 b is filled.

  By attaching the sponge 37 to the attachment portion 34b, the workability of the attaching operation of the sponge 37 is improved as compared with the case of attaching to the developing case 30. In other words, the portion of the developing case 30 that contacts the sponge 37 has a shape that is recessed inward, so that the sponge 37 is attached to the mounting portion 34b in advance rather than sticking the sponge 37 in place while visually confirming this portion. It is easier to apply the sponge 37.

  The sponge 37 is affixed to the attachment portion 34b such that the lower end surface 37a coincides with the lower end surface 34b3 of the attachment portion 34b. On the other hand, when the lower end surface 37a of the sponge 37 protrudes downward from the lower end surface 34b3, the protruding portion may ride on an end seal 38 described later. This embodiment is preferable because the above configuration can prevent this ride-up. Here, the lower end surface 37a and the lower end surface 34b3 are end surfaces on the side where the developing roller 13 is provided on the opening side of the developing device.

  Further, the lower end surface 34b3 of the attachment portion 34b is provided so as to coincide with the opening end 30c2 (see FIG. 7a) of the developing case 30. Thereby, it is possible to suppress toner regulated by the developing blade 34 and peeled off from the developing roller from adhering to the opening end 30c2 of the developing case 30 or the upper portion of the developing case 30.

  Next, the relationship between the width of the gap W1 in which the sponge 37 and the sponge 37 are provided will be described. As shown in FIG. 5, the gap W <b> 1 is a gap formed between the developing case 30 and the attaching portion of the attaching portion 34 b to the developing case 30. The gap W1 is a gap formed between the developing case 30 and the mounting portion 34b by providing a portion of the seating surface 30e1 (see FIG. 4) of the fastening boss 30e. Therefore, the gap width is provided to be substantially the same as the height H1 of the seating surface 30e1.

The sponge 37 is provided with a thickness equal to or greater than the width H1 of the gap W1 in order to fill the gap W1. Then, by attaching the developing blade 34 to the developing case 30, the sponge 37 is sandwiched between the developing case 30 and the attaching portion 34b and is compressed until the thickness thereof becomes the same as the width H1 of the gap W1. Therefore, when the thickness of the sponge 37 before compression is H0, the compression rate Ta is
Compression rate Ta (%) = ((H0−H1) / H0) * 100
Can be defined as For example, when the thickness H0 of the sponge 37 is 3 mm and the width H1 of the gap W1 is 1 mm, the compression rate is ((3-1) / 3) * 100, which is about 67%. In order to sufficiently seal the gap W1 and prevent the toner from flowing out, the compression rate of the sponge 37 is desirably 40% or more. On the other hand, if the compression ratio becomes too large, the repulsive force of the compressed sponge 37 against the developing case 30 and the developing blade 34 increases, and there is a possibility that the developing case 30 and the developing blade 34 may be deformed. The rate is desirably 80% or less.

  FIG. 6 is a perspective view showing a mounting portion of the developing roller and the regulating blade on one end side in the axial direction of the developing roller, and the developing roller and the regulating blade are not shown.

  As shown in FIG. 6, the developing case 30 is provided with an end seal 38 as a second seal member at a position corresponding to the axial end portion of the developing roller. The end seal 38 is formed in a two-layer structure including a felt 38 a that contacts the peripheral surface of the developing roller and a sponge 38 b that is attached to the developing case 30.

  By constituting the sliding surface side of the end seal 38 with felt having excellent wear resistance, the end seal 38 can be made less likely to be worn by sliding with the developing roller. On the other hand, since felt has a strong repulsive force against the developing roller, if the end seal 38 is composed only of felt, the frictional force generated between the end seal 38 and the developing roller increases when the developing roller rotates. Cheap. For this reason, in this embodiment, the sponge 38b is provided on the sticking surface side of the end seal 38. Thereby, the repulsive force of the end seal 38 against the developing roller due to the compression of the sponge can be reduced, and the frictional force generated between the end seal 38 and the developing roller can be prevented from becoming excessively large.

  Further, an inter-seal gap W2 having a width L1 (hereinafter also simply referred to as a gap W2) is provided between the sponge 37 and the end seal 38. Then, by filling the gap W2 with the silicon sealant 39 as a filler, the toner is prevented from flowing out of the developing device from the gap W2.

  Silicone sealants are viscous liquids and have the property of solidifying over time. Due to such a property, the silicon sealant 39 filled in the gap W2 can be solidified after being spread in the gap W2 due to its viscosity, so that the toner flows out from the gap W2. Can be prevented. In this embodiment, the silicon sealant is used as the filler to fill the gap W2. However, the present invention is not limited to this, and any material that has the same properties as the above and spreads in the gap W2 and solidifies can be used as the filler. Can be used.

  In addition, unlike the configuration of the present embodiment, a configuration in which no gap is set between the sponge 37 and the end seal 38 and no filler is applied may be considered. However, in this case, a gap may be generated between the sponge 37 and the end seal 38 due to component tolerances, attachment errors, or the like. There is a possibility that a gap may be formed between 37 and the developing case 30. Therefore, in this embodiment, the gap W2 is set in advance between the sponge 37 and the end seal 38, and the silicon sealant 39 is applied to the gap to prevent the toner from flowing out.

  The order of assembling these end seals 38, the developing blade, etc. to the developing case 30 (the order in manufacturing the developing device) is as follows. First, as shown in FIG. 7A, an end seal 38 is attached to the developing case 30. Then, as shown in FIG. 7B, a silicon sealant 39 is applied at a position corresponding to the gap W2. Thereafter, the developing blade 34 to which the sponge 37 is attached is assembled to the developing case 30 and fixed with screws 36, and then the developing roller 13 is assembled to the developing case 30 (see FIG. 3).

  As described above, the silicon sealant 39 is applied in a state where the developing blade 34 is not assembled to the developing case 30. In this state, the sponge 37 is not disposed in the developing case 30, and the gap W2 is not formed. Therefore, with such a configuration, an appropriate amount of the silicon sealant 39 cannot be applied according to the size of the gap W2.

  In this case, in order to reliably close the gap W2 with the silicon sealant 39, it is necessary to apply a large amount of the silicon sealant 39 with a margin. However, if a large amount of the silicon sealant 39 is applied, the amount of the applied silicon sealant 39 becomes excessive and overflows from the gap W2 when the size of the gap W2 becomes smaller than the width set by the component tolerance or the like. The silicon sealant 39 spreads more than expected. Then, when the silicon sealant 39 flows inward in the axial direction, it mixes with the toner in the developing case 30 to be filled thereafter, or adheres to the surface of the developing roller to be attached and solidifies to become foreign matter, and white This may cause abnormal image formation such as streaks.

  On the other hand, it is also conceivable that the developing blade 34 is assembled to the developing case 30 and a gap W2 is provided between the sponge 37 and the end seal 38, and then an appropriate amount of silicon sealant 39 is applied to the gap W2. In this case, an injection hole is provided at a predetermined position of the developing blade 34 so that the gap W2 can be visually recognized in a state where the developing blade 34 is assembled to the developing case 30, and an appropriate amount of silicon sealant 39 is injected. A method of injecting into the gap W2 from the hole can be adopted. However, in such a configuration, when the developing blade 34 is assembled to the developing case 30, the sponge 37 and the end seal 38 are crushed and spread by the developing roller and the gap W2 is narrowed. Yes. In this state, even if the silicon sealant 39 is injected into the gap W2, the gap W2 is not sufficiently reached until the silicon sealant 39 is solidified, and the gap W2 cannot be sealed. From the above, in this embodiment, a configuration in which the silicon sealant 39 is filled before the developing blade 34 is assembled to the developing case 30 is employed.

  Next, based on the above problems, the configuration of the present embodiment for preventing the silicon sealant 39 from flowing out in the axial direction will be described with reference to FIGS. 8 to 10 below. In FIG. 8, the developing roller, the developing blade, and the sponge are not shown, and in FIG. 9, the developing roller and the developing blade are not shown.

  As shown in FIG. 8, in the present embodiment, the convex body 40 is provided at a position corresponding to the gap W <b> 2 of the developing case 30 and facing the inner side in the axial direction of the end seal 38. As shown in FIG. 9, the convex body 40 extends from the sponge 37 toward the end seal 38 and contacts the sponge 37 and the end seal 38. As shown in FIG. 10, the convex body 40 is a convex portion provided so as to protrude from the filling space M filled with the silicon sealant 39, and protrudes in the thickness direction of the sponge 37 and the end seal 38. Provided. In the present embodiment, the convex body 40 is formed by a part of the developing case 30. However, the convex body 40 may be formed of a member separate from the developing case 30. In the developing device assembly process, the protruding direction of the convex body 40 (upward in FIG. 10) is the upper side in the direction of gravity.

  By providing the convex body 40, the filling space M and the space on the inner side in the axial direction (right side in the drawing) from the filling space M are partitioned. Thereby, the convex body 40 becomes a wall with respect to the silicon sealant 39 filled in the filling space M, and the silicon sealant 39 flows out from the convex body 40 to the inner side in the axial direction (side in the arrow direction in the drawing). Can be prevented. In particular, as described above, the convex body 40 abuts on the sponge 37 and the end seal 38 and is provided over the entire width of the gap W2, so that the silicon sealant 39 flowing inward in the axial direction can be dammed without gaps.

  As described above, the convex body 40 is preferably provided in contact with the sponge 37 and the end seal 38. On the other hand, if the width of the convex body 40 is set too long, the sponge riding on the convex body 40 is provided. The range of 37 and the end seal 38 is enlarged, and the seal pressure to the developing roller is excessively increased. Therefore, in the present embodiment, the width of the convex body 40 is set to an appropriate width in consideration of component tolerances and the like. For example, if the pasting errors of the sponge 37 and the end seal 38 are ± 0.5 mm, and the component tolerances of the sponge 37 and the end seal 38 are ± 0.5 mm, respectively, the tolerance of the width L1 of the gap W2 is ± 2. 0 mm. When the width L1 of the gap W2 is set to 3.0 mm, the actual width L1 varies in the range of 1.0 to 5.0 mm. At this time, for example, considering that the above-described riding width is not excessively increased, the width of the convex body 40 is preferably set to about 3 to 5 mm.

  Further, when the end seal 38 is affixed to the developing case 30, the affixing error of the end seal 38 can be reduced by affixing the end seal 38 with reference to the end position in the longitudinal direction of the convex body 40. ,preferable. In addition, this makes it possible to suppress the end seal 38 from riding on the convex body 40.

  Further, the height H3 of the convex body 40 is preferably set as high as possible in order to prevent the silicon sealant 39 from getting over the convex body 40 and flowing out in the axial direction. On the other hand, if the height of the convex body 40 is increased too much, it interferes with the mounting portion 34b of the developing blade 34, presses the mounting portion 34b, and deforms the developing blade 34. Therefore, the convex body 40 needs to be set to a height that does not interfere with the developing blade 34. For example, when the flatness of the mounting portion 34b is 0.2 mm, the height of the convex body 40 is set to a height of H1-0.2 (mm) or less. Further, the flatness of the surface facing the mounting portion 34b of the developing case 30 and the tolerance of the height of the convex body 40 may be taken into consideration.

As described above, the convex body 40 is provided in contact with the sponge 37 and the end seal 38, and a part of the sponge 37 and the end seal 38 rides on the convex body 40. The sponge 37 riding on the convex body 40 is compressed between the mounting portion 34b and the convex body 40, and the width is a width obtained by subtracting the height of the convex body 40 from the width H1 of the gap W1. H2. Therefore, the compression rate of the sponge 37 in this part is
Compression rate Tb (%) = ((H0−H2) / H0) * 100
Can be defined as
For example, if the thickness H0 of the sponge 37 is 3 mm, the width H1 of the gap W1 is 1 mm, and the height H3 of the convex body 40 is 0.5 mm, the width H2 is 0.5 (= 1−0.5) mm. The compression rate is (3-0.5) / 3 * 100, which is about 83%. As described above, it is a part of the sponge 37 that rides on the convex body 40, and its range is limited. However, it is preferable that the repulsive force of the sponge 37 in the riding portion is not excessively increased. It is preferable to set the compression rate to be 90% or less.

  The convex body 40 has an R chamfer at the tip in the height direction. As a result, the sponge 37 and the end seal 38 riding on the convex body 40 can be brought into contact with each other on the R surface instead of the corners. Thereby, when the sponge 37 and the end seal 38 ride on the convex body 40, the pressure applied to the sponge 37 and the end seal 38 can be reduced, and the developing case 30 of the sponge 37 and the end seal 38 can be reduced. The repulsive force with respect to etc. can be reduced. The chamfering provided on the convex body 40 may be C chamfering.

Next, an embodiment different from the above developing device will be described with reference to FIG.
As shown in FIG. 11, in the present embodiment, a recess 30 g is provided in the filling portion 30 f of the developing case 30 where the silicon sealant 39 is filled. As in the above-described embodiment, in the developing device assembly process, the protruding direction of the convex body 40 (the upward direction in FIG. 10) is the upper side in the gravity direction, and the silicon sealant 39 filled in the filling portion 30f has its own weight. Can spread toward the concave portion 30g.

  The concave portion 30g is provided with an inclined surface 30g1 whose depth increases from the inner side in the axial direction (side on which the convex body 40 is provided) to the outer side in the axial direction.

  By providing the convex body 40 as in the above-described embodiment, the flow of the silicon sealant 39 in the axial direction inner side than the convex body 40 can be blocked, and the silicon sealant 39 is mixed with toner and abnormal. It can be prevented from causing an image. However, on the other hand, by providing the convex body 40 and blocking the flow of the silicon sealant 39, the filling amount of the silicon sealant 39 on the axially outer side from the convex body 40 is increased, and the sponge 37, the end seal 38, etc. There is a risk of spreading.

  By providing the recess 30g, it is possible to increase the capacity of the silicon sealant 39 that can be filled in the filling part 30f, and to prevent the silicon sealant 39 from spreading on the sponge 37 and the end seal 38.

  Further, by providing the inclined surface 30g1 in the concave portion 30g, the silicon sealant 39 dammed by the convex body 40 can be smoothly filled into the concave portion 30g down the inclined surface 30g1.

  By the way, if the concave portion 30g is too far from the convex body 40, a lot of the silicon sealant 39 spreads on the sponge 37 and the end seal 38 before reaching the concave portion 30. Therefore, it is preferable to provide the recessed part 30g in the range of 10 mm or less from the convex body 40 to an axial direction outer side, and is provided in the distance of 5-10 mm from the convex body 40 in this embodiment.

  In addition, by providing the R surface 30g3 between the inclined surface 30g1 and the bottom surface 30g2, it becomes easier to fill the silicon sealant 39 in this portion than in the case of forming the corner portion.

  The embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the gist of the present invention.

  The image forming apparatus according to the present invention is not limited to the color image forming apparatus shown in FIG. 1, but may be a monochrome image forming apparatus, a copying machine, a printer, a facsimile, or a complex machine thereof.

  Recording media include paper P (plain paper), thick paper, postcards, envelopes, thin paper, coated paper (coated paper, art paper, etc.), tracing paper, OHP sheet, plastic film, prepreg, copper foil, etc. included.

  In the above embodiment, the second seal member is an end seal having a two-layer structure of felt and sponge. However, the present invention is not limited to this, and, for example, a single-layer structure including only a felt or a three-layer structure or more can be employed depending on the sealing property required for the second seal member and the allowable repulsive force.

  Moreover, in the above embodiment, sponge was used as a member on the sticking surface side of the first seal member or the second seal member. However, the present invention is not limited to this, and a member having appropriate elasticity can be used. Further, the member used on the sliding surface side of the second seal member is not limited to the felt of this embodiment, and a member having excellent wear resistance can be appropriately employed.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 12 Developing apparatus 13 Developing roller (developer carrier)
30 Developing case (housing)
30f Filling part 30g Concave part 30g1 Inclined surface 30g2 Bottom surface 34 Developing blade (regulating member)
34a Restriction part 34b Mounting part 37 Sponge (first seal member)
38 End seal (second seal member)
39 Silicone sealant (filler)
40 Convex body W1 Gap W2 Seal gap M Filling space

JP 2014-174462 A

Claims (10)

A housing,
A developer carrying member rotatably provided on the housing and carrying a developer on a surface thereof;
An attachment portion attached to the housing, and one end side of the developer that is held by the attachment portion, and the other end side of the developer carrying member is extended to the developer carrying member side and carried on the surface of the developer carrying member. A regulating member having a regulating part that regulates the layer thickness to a certain level or less;
A first seal member provided between the mounting portion and the housing, and filling the gap;
A developing device provided with a second seal member provided in contact with the circumferential surface on the axial end side of the developer carrying member and filling a gap between the developer carrying member and the housing in the portion. ,
A gap between the seals is provided between the first seal member and the second seal member,
Between the seal gaps, a filler for filling the gaps between the seals is filled,
The casing extends from the first seal member side to the second seal member side in the gap between the seals and contacts at least one of the first seal member and the second seal member. , Having a convex body provided protruding from the filling space filled with the filler,
The developing device according to claim 1, wherein the convex body partitions the filling space and a space closer to an axially central side of the developer carrying body than the filling space.   The developing device according to claim 1, wherein an R chamfering or a C chamfering is performed on a tip portion of the convex body.   The developing device according to claim 1, wherein a gap width between the convex body and the attachment portion is provided with a size equal to or greater than the flatness of the attachment portion. The thickness of the first seal member before assembly to the developing device is H0,
The gap width of the gap between the mounting portion on which the first seal member is provided and the housing is H1,
The compression rate Ta of the first seal member in the part,
Ta (%) = ((H0−H1) / H0) * 100
Defined as
The developing device according to claim 1, wherein the compression rate Ta is set to 40% or more and 80% or less. The thickness of the first seal member before assembly to the developing device is H0,
The gap width between the mounting portion on which the first seal member is provided and the convex body is H2,
The compression rate of the first seal member in the part is
Tb (%) = ((H0−H2) / H0) * 100
Defined as
The developing device according to claim 1, wherein the compression rate Tb is set to 90% or less.   The developing device according to claim 1, wherein the casing is provided with a concave portion in a filling portion of the filler.   The developing device according to claim 6, wherein the concave portion has an inclined surface that descends from the convex body side toward the bottom surface of the concave portion. A latent image carrier for carrying a latent image;
A developing device according to any one of claims 1 to 7,
A process unit in which the housing holds the latent image carrier.   An image forming apparatus comprising the developing device according to claim 1. A housing,
A developer carrying member rotatably provided on the housing and carrying a developer on a surface thereof;
An attachment portion attached to the housing, and one end side of the developer that is held by the attachment portion, and the other end side of the developer carrying member is extended to the developer carrying member side and carried on the surface of the developer carrying member. A regulating member having a regulating part that regulates the layer thickness to a certain level or less;
A first seal member provided between the mounting portion and the housing, and filling the gap;
A developing device manufacturing method comprising: a second seal member provided in contact with a circumferential surface on an axial end portion side of the developer carrier, and filling a gap between the developer carrier and the housing in the portion. Because
A gap between the seals is provided between the first seal member and the second seal member,
Between the seal gaps, a filler for filling the gaps between the seals is filled,
The casing extends from the first seal member side to the second seal member side in the gap between the seals and contacts at least one of the first seal member and the second seal member. , Having a convex body provided protruding from the filling space filled with the filler,
The convex body is a method for manufacturing a developing device that partitions the filling space and the space on the axially central side of the developer carrier from the filling space,
Filling the filling space with the filler;
And a step of assembling the regulating member to which the first seal member is attached to the housing after the step.

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