JP2016161584A - Development device, development cartridge, and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a development device, a development cartridge, and a process cartridge having a seal configuration capable of being stably manufactured while reducing the number of components to constitute without enlarging the device.SOLUTION: A development device 4 includes: an end part seal 141 for sealing a gap between a first development frame body 131 and a developer carrier 25 in an end part in a longitudinal direction of the developer carrier 25 when the development carrier 25 is arranged so as to overlap with an opening 133. The development device 4 is integrally formed with the first development frame body 131, and includes a seal member 144 connected to an end part seal 141 that seals between the first development frame body 131 and a second development frame body 132.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a developing device for developing an electrostatic latent image, a developing cartridge that can be attached to and detached from an image forming apparatus, and a process cartridge.

  2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic image forming process, a cartridge system in which a cartridge such as a developing cartridge or a process cartridge is detachable from an image forming apparatus main body has been adopted. In such a cartridge system, a configuration is adopted in which a plurality of seal members are used to seal between frames and parts constituting the cartridge so that the developer stored in the cartridge does not leak to the outside.

  As the sealing member, an elastic body such as urethane foam, soft rubber, or elastomer resin is often used. And the sealing member is provided in the junction part between frames and between components, and the method of compressing and deforming and sealing with a predetermined amount of crushing is generally used.

  In the developing device (developing unit) in the developing cartridge or process cartridge, a configuration is adopted in which the developer carrying member (developing roller) carrying and carrying the developer is exposed at the developer supply opening of the developing frame. . At both ends of the longitudinal direction of the developer supply opening, there is a flexible end seal member having a surface that is rubbed against the developing roller formed of felt or the like to seal a gap between the developing roller and the developing frame. The toner is disposed with a predetermined intrusion amount with respect to the developing roller. Further, at the developer supply opening, a sheet member (hereinafter referred to as a blow-off preventing sheet) that abuts against the developing roller and prevents the developer from being blown to the outside is provided by a sticking means such as a double-sided tape. It is attached to the sheet pasting surface which constitutes a part. The blowout prevention sheet is disposed so as to overlap with the end seal member, thereby preventing leakage of the developer between the developing roller, the end seal member, and the blowout prevention sheet.

  On the other hand, the gap formed between the blowout prevention sheet, the end seal member, and the developing frame may be separately sealed with another seal member.

  On the other hand, the development frame is often configured by joining a plurality of frames by means such as welding for reasons such as manufacturing shape restrictions. In particular, since the vicinity of the developer supply opening has a complicated shape, it is often composed of a plurality of frames, and the frame to which the blowout prevention sheet is attached and the frame to which the end seal member is attached May be different. In the case of such a developing frame, since a gap is generated between the frames in a place where they cannot be joined by means such as welding, it is necessary to separately seal the gap between the frames with another sealing member. is there. Therefore, conventionally, an elastic sealing member such as foamed urethane foam is sandwiched between the frames that cannot be sealed by means such as welding and sealed.

  As described above, it is necessary to further seal the gap formed between the blowout prevention sheet, the end seal member, the developing frame, the elastic seal member, and the like with another seal member. The gap formed between these parts becomes very complicated due to the mounting position and shape variation of each part, so it is difficult to seal with only sealing members such as urethane foam. It is. Therefore, as a means for sealing such a complicated gap, a method of applying and sealing a coating material such as hot melt in the gap is generally used (see Patent Document 1).

JP 2004-126003 A

  In a method of sealing a gap having a complicated shape by applying a coating material such as hot melt in the gap, the coating hole of the coating device is brought close to the coating portion to stabilize the coating material. It is applied. However, if it is difficult to get close enough due to shape restrictions, etc., it will be difficult to apply non-rigid devices to manufacture non-defective products because variations in application position and thread-like application material will easily adhere to places other than the desired location. Management was necessary. On the other hand, since the number of parts constituting the process cartridge is large, the volume of the gap is likely to fluctuate due to the influence of assembly accuracy. Since it is necessary to increase the coating amount of the coating agent in consideration of the variation in the volume of the gap, the buffer portion for escaping unnecessary coating material becomes large, and as a result, the developing device, the developing device, and the process cartridge It was the cause of increasing the volume.

  The present invention is a further development of the above-described prior art, and a developing device, a developing cartridge, and a process having a seal configuration that enables stable production while reducing the number of components without increasing the size of the device To provide a cartridge.

  In order to achieve the above object, a developing device used in the image forming apparatus according to the present application is provided with a developer carrier for supplying a developer to the image carrier and an opening for supplying the developer to the developer carrier. When the first developing frame, the second developing frame fixed to the fixing surface of the first developing frame, and the developer carrying member are arranged so as to overlap the opening, the longitudinal direction of the developer carrying member And an end seal that seals a gap between the first developing frame and the developer carrier at the end. The developing device is a seal member that is formed integrally with the first developing frame and is connected to the end seal, and a seal member that seals between the first developing frame and the second developing frame. Furthermore, it is characterized by having.

  As described above, according to the present invention, it is possible to provide a developing device, a developing cartridge, and a process cartridge having a seal configuration capable of stable production while reducing the number of components without increasing the size of the device. It is possible.

It is a figure which shows the seal structure under the blowing prevention sheet | seat which concerns on an Example. 1 is a diagram illustrating a configuration of an image forming apparatus equipped with a process cartridge according to an embodiment. FIG. It is a figure explaining the process cartridge which concerns on an Example. It is a figure explaining the external appearance of the developing unit which concerns on an Example. It is a figure explaining the state which removed the developing roller of the developing unit which concerns on an Example. FIG. 6 is a diagram illustrating a configuration around a toner supply opening according to an exemplary embodiment. It is a figure explaining the 1st image development frame body of the state which carried out the mold clamping which concerns on an Example. It is a figure explaining the 1st image development frame with which the seal member concerning an example was fabricated. It is a figure explaining the 2nd image development frame before welding concerning an example. It is a figure explaining the developing device frame after welding concerning an example. It is a figure explaining the protrusion amount of the sealing member which concerns on an Example. It is a figure explaining height optimization of the sealing member which concerns on an Example. It is a figure explaining the protrusion amount after optimization of the sealing member which concerns on an Example. It is a figure explaining the contact | adherence method of the sealing member which concerns on an Example, and a blowing prevention sheet | seat.

  Hereinafter, an image forming apparatus and a process cartridge according to the present invention will be described with reference to the drawings. An electrophotographic image forming apparatus (hereinafter, image forming apparatus) forms an image on a recording medium using an electrophotographic image forming process. Examples of the image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (for example, a laser beam printer, an LED printer), a facsimile machine, and a word processor.

  The developing device is a device for developing the electrostatic latent image formed on the electrophotographic photosensitive drum with a developer. The developing unit, the developing frame that supports the developing unit, and components related to the developing unit. Etc. are constituted. Examples of developing means include a developing roller, a coating roller, and a developing blade. The developing cartridge is a cartridge in which the developing unit, the developing frame that supports the developing unit, and parts related to the developing unit are integrated into a cartridge so that the developing unit can be attached to and detached from the image forming apparatus main body. It is a kind.

  The process cartridge is a cartridge in which the developing means, the electrophotographic photosensitive drum, and the process means acting on the developing means are integrated into a cartridge that is detachable from the main body of the image forming apparatus. Examples of the process means include a charging means, a developing means, and a cleaning means that act on the electrophotographic photosensitive drum. As a typical process cartridge configuration, a developing unit (developing device) having a developing unit and a cleaning unit having a photosensitive drum, a cleaning unit, a charging unit, and the like are rotatably coupled. .

(Overall configuration of image forming apparatus)
First, the overall configuration of the image forming apparatus 100 will be described with reference to FIG. As shown in FIG. 2, four detachable process cartridges 70 (70a, 70b, 70c, 70d) are mounted by mounting members (not shown). Further, the upstream side in the mounting direction of the image forming apparatus 100 of the process cartridge 70 is defined as the front side surface, and the downstream side in the mounting direction is defined as the back side surface side. In FIG. 2, the process cartridge 70 is provided in the apparatus main body 100 so as to be inclined with respect to the horizontal direction.

  Each process cartridge 70 has a photosensitive drum (image carrier) 1 (1a, 1b, 1c, 1d), a charging roller 2 (2a, 2b, 2c, 2d) and process means around the photosensitive drum 1. They are arranged integrally. Examples of the process means include a developing roller (developer carrier) 25 (25a, 25b, 25c, 25d) and a cleaning member 6 (6a, 6b, 6c, 6d). The charging roller 2 uniformly charges the surface of the photosensitive drum 1, and the developing roller 25 develops a latent image formed on the photosensitive drum 1 with a developer (hereinafter referred to as toner) to form a visible image. It is to become. The cleaning member 6 removes the toner remaining on the photosensitive drum 1 after the toner image formed on the photosensitive drum 1 is transferred to a recording medium.

  A scanner unit 3 for selectively exposing the photosensitive drum 1 based on image information and forming a latent image on the photosensitive drum 1 is provided below the process cartridge 70.

  A cassette 17 containing a recording medium S is attached to the lower part of the apparatus main body 100. A recording medium conveying unit is provided so that the recording medium S passes through the secondary transfer roller 69 and the fixing unit 74 disposed above the apparatus main body 100 and is conveyed above the apparatus main body 100. That is, the feeding roller 54 for separating and feeding the recording medium S in the cassette 17 one by one, the conveying roller pair 76 for feeding the fed recording medium S, and the latent image and the recording medium formed on the photosensitive drum 1. A registration roller pair 55 for synchronizing with S is provided. Further, intermediate transfer as intermediate transfer means for transferring the toner image formed on each photosensitive drum 1 (1a, 1b, 1c, 1d) above the process cartridge 70 (70a, 70b, 70c, 70d). A unit 5 is provided. The intermediate transfer unit 5 has a driving roller 56, a driven roller 57, a primary transfer roller 58 (58 a, 58 b, 58 c, 58 d) that faces the photosensitive drum 1 of each color, and a position that faces the secondary transfer roller 69. The transfer belt 9 is stretched over the counter roller 59. Then, the transfer belt 9 circulates and moves in the direction A in FIG. 2 so as to face and be in contact with all the photosensitive drums 1 and apply a voltage to the primary transfer rollers 58 (58a, 58b, 58c, 58d). Thus, primary transfer is performed from the photosensitive drum 1 onto the transfer belt 9. The toner on the transfer belt 9 is transferred to the recording medium S by applying a voltage to the opposing roller 59 and the secondary transfer roller 69 disposed in the transfer belt 9.

  When forming an image, each photosensitive drum 1 is rotated, and the photosensitive drum 1 uniformly charged by the charging roller 2 is selectively exposed from the scanner unit 3. Thereby, an electrostatic latent image is formed on the photosensitive drum 1. The latent image is developed by the developing roller 25. As a result, each color toner image is formed on each photosensitive drum 1. Next, in the intermediate transfer unit 5, primary transfer of each color toner image is performed from the photosensitive drum 1 onto the transfer belt 9 circulating in the direction A in FIG. In synchronization with image formation, the registration roller pair 55 conveys the recording medium S to the secondary transfer position where the opposing roller 59 and the secondary transfer roller 69 are in contact with each other with the transfer belt 9 interposed therebetween. At the secondary transfer position, each color toner image on the transfer belt is secondarily transferred to the recording medium S by applying a transfer bias voltage to the secondary transfer roller 69. As a result, a color image is formed on the recording medium S. The recording medium S on which the color image is formed is heated and pressed by the fixing unit 74 to fix the toner image. Thereafter, the recording medium S is discharged to the discharge unit 75 by the discharge roller 72.

(Overall configuration of process cartridge)
Next, a process cartridge 70 embodying the present invention will be described with reference to FIG. FIG. 3 is a main cross section of a process cartridge 70 containing toner. The cartridge 70a containing yellow toner Y, the cartridge 70b containing magenta M toner, the cartridge 70c containing cyan C toner, and the cartridge 70d containing black Bk toner have the same configuration. .

  The process cartridge 70 (70a, 70b, 70c, 70d) has a cleaning unit 26 (26a, 26b, 26c, 26d) and a developing unit 4 (4a, 4b, 4c, 4d). The cleaning unit 26 includes a photosensitive drum 1 (1a, 1b, 1c, 1d), a charging roller 2 (2a, 2b, 2c, 2d), a cleaning member 6 (6a, 6b, 6c, 6d), and a cleaning frame. And a body 27. The developing unit 4 includes a developing roller 25 and a developing frame 31.

  A charging roller 2 and a cleaning member 6 are disposed on the circumference of the photosensitive drum 1. The cleaning member 6 includes an elastic member 7 formed of a rubber blade and a cleaning support member 8. The tip 7 a of the rubber blade 7 is disposed in contact with the rotation direction of the photosensitive drum 1 in the counter direction. The residual toner removed from the surface of the photosensitive drum 1 by the cleaning member 6 falls into the removed toner chamber 27a. In addition, a squeeze sheet 21 that prevents the removed toner in the removed toner chamber 27 a from leaking is in contact with the photosensitive drum 1. Then, by transmitting the driving force of a main body driving motor (not shown) as a driving source to the cleaning unit 26, the photosensitive drum 1 is rotationally driven according to the image forming operation. The charging roller 2 is rotatably attached to the cleaning unit 26 via the charging roller bearing 28, and is pressurized toward the photosensitive drum 1 by the charging roller pressing member 46 and is rotated following the photosensitive drum 1. .

  The cleaning unit 26 and the developing unit 4 can be rotated by press-fitting support pins 14 and 15 into holes formed in the cleaning frame 27 of the cleaning unit 26 and the developing bearings 12 and 13 of the developing unit 4. It is said that. The cleaning unit 26 and the developing unit 4 are biased by a contact spring 38 so that the photosensitive drum 1 of the cleaning unit 26 and the developing roller 25 of the developing unit 4 are in contact with each other. At the time of non-image formation, the pressing portion 31b of the developing frame 31 is pressed so as to compress the contact spring 38, and the photosensitive drum 1 and the developing roller 25 are separated from each other with the support pins 14 and 15 as rotational centers. Has been able to let you.

(Development unit configuration)
Next, the developing unit 4 as a developing device will be described with reference to FIGS. 4 is an external view of the developing unit 4, and FIG. 5 is a view showing a state in which the developing roller 25 and the developing bearings 12 and 13 are removed. The developing unit 4 includes a developing roller 25 that contacts the photosensitive drum 1 and rotates in the direction of arrow B, and a developing frame 31 that supports the developing roller 25. The developing roller 25 is rotatably supported by the developing frame 31 via developing bearings 12 and 13 attached to both sides of the developing frame 31, respectively. A toner supply roller 34 that rotates in contact with the developing roller 25 and a developing blade 35 that regulates the toner layer on the developing roller 25 are disposed on the circumference of the developing roller 25.

  As shown in FIG. 5, the developing frame 31 is composed of a first developing frame 131 and a second developing frame 132, and is in a state of being integrally coupled by means such as welding. Further, the developing frame 31 is provided with a toner supply opening (opening) 133 for supplying the toner carried by the developing roller 25 to the photosensitive drum 1, and the developing roller 25 has a toner supply opening 133. It is supported so as to be exposed to the outside. Further, as shown in FIG. 3, the toner storage chamber 31 a of the developing frame 31 is provided with a toner transport member 36 for stirring the stored toner and transporting the toner to the toner supply roller 34.

(Seal configuration around the toner supply opening)
Next, a seal configuration around the toner supply opening 133 will be described with reference to FIGS. 5 and 6.

  First, the configuration of the toner supply opening 133 provided in the developing frame 31 will be described. As shown in FIG. 6, the toner supply opening 133 includes a developing blade mounting portion 131 a of the first developing frame 131, end seal mounting portions 131 b disposed at both longitudinal ends of the first developing frame 131, and a second A space surrounded by the sheet pasting surface 132a of the developing frame 132. As described above, the developing roller 25 is disposed so as to be exposed and overlapped with the toner supply opening 133. The developing frame 31 is filled with toner used for development. A plurality of seal members are provided around the toner supply opening 133 so as to contact the developing roller 25 so that the filled toner does not leak to the outside.

  First, end seals 141 for sealing between the developing frame 31 and the developing roller 25 are provided at the end seal attaching portions 131b provided at both ends of the toner supply opening 133 in the longitudinal direction. The surface layer 141a of the end seal 141 in contact with the developing roller 25 is made of felt, pile, woven fiber, knitted fabric, or the like, and rubs against the surface of the developing roller 25 to prevent the toner from leaking. Further, if necessary, a cushion layer 141b such as a sponge is provided in the lower layer to optimize the contact pressure against the developing roller 25. The lowermost layer 141c of the end seal 141 is provided with an attaching means such as a double-sided tape, and is attached to the end seal attaching portion 131b by this.

  Next, as described above, the developing blade 35 is in contact with the circumference of the developing roller 25. As shown in FIG. 5, the developing blade 35 is disposed so as to overlap the end seals 141 disposed at both ends in the longitudinal direction. As shown in FIG. 4, when the developing roller 25 is attached, the developing blade 35 is pressed against the end seal 141 by the developing roller 25, and from the boundary between the end seal 141 and the developing blade 35. This prevents toner from leaking.

  As shown in FIG. 6, a lower blade seal 142 such as urethane foam is provided on the lower side of the developing blade 35, and is sandwiched between the developing blade 35 and the first developing frame 131, thereby lowering the developing blade 35. This prevents toner leakage from the toner. At this time, the gap 143 generated between the blade lower seal 142 and the end seal 141 is sealed by applying an application material (not shown) such as hot melt from the blade application hole 35a shown in FIG. .

  Further, as shown in FIG. 5, the blowout prevention sheet 20 is in contact with the circumference of the developing roller 25 for the purpose of preventing toner leakage from the toner supply opening 133. The blowout prevention sheet 20 is attached to the sheet sticking surface 132a of the second developing frame 132 by a sticking means 120 such as a double-sided tape. Similar to the developing blade 35, the blowout prevention sheet 20 is disposed so as to overlap the end seals 141 disposed at both longitudinal ends. As shown in FIG. 4, when the developing roller 25 is attached, the blowing prevention sheet 20 is pressed against the end seal 141 by the developing roller 25, and the boundary between the end seal 141 and the blowing prevention sheet 20. The toner is prevented from leaking from the part.

  Next, the seal configuration of the gap generated between the end seal 141, the blowout prevention sheet 20, the first developing frame 131, and the second developing frame 132 will be described. Hereinafter, the gap will be described as a seal configuration under the blowing prevention sheet.

(Seal configuration under the blowout prevention sheet)
Next, the seal configuration under the blowout prevention sheet according to the present embodiment will be described. In addition, since it is the same structure on both sides in the longitudinal direction, the configuration of the seal will be described by taking one of the end portions in the longitudinal direction as an example.

  FIG. 1 is a cross-sectional view showing the XX cross section shown in FIG. 5, and shows a configuration in which the developing blade 35 is removed in order to explain the seal member 144. FIG. 7 shows a mold 145 for molding a seal member 144 made of a thermoplastic elastomer on the first developing frame 131 before the first developing frame 131 and the second developing frame 132 are welded. It is the figure which showed the state fastened. FIG. 7 is a cross-sectional view of the same portion as the XX cross-section for explaining the formation process of the seal member 144. As shown in FIG. 7, an end seal 141 is attached in advance to the first developing frame 131 before welding. In this state, a mold 145 is clamped on the first developing frame 131, and a seal member 144 is formed on the seal molding portion 131d. The first developing frame 131, the end seal 141, and the seal The member 144 is integrated. That is, the seal member 144 sticks to the first developing frame 131 and the seal member 144 penetrates and is connected to the end seal 141. At this time, the mold 145 is in close contact with the developing device frame 131 to prevent leakage of the elastomer resin, and at the same time, enters the end seal 141 by a predetermined amount to prevent the elastomer resin from leaking onto the surface layer 141a. It is preventing. The seal member 144 formed in this manner is in close contact with the first developing frame 131 and the surface layer 141a of the end seal 141 from the lowermost layer 141c, and toner leaks from the boundary between these parts. Can be prevented. That is, one end of the seal member 144 is sealed by being sandwiched between the welded portions. On the other hand, at the other end of the seal member 144 on the end seal 141 side, there is a gap between the blowing prevention sheet 20, the end seal 141, the first developing frame 131, and the second developing frame 132. .

  Here, FIG. 8 is a view showing the first developing frame 131 in which the seal member 144 is formed. Since the seal member 144 is molded using a mold, variations in shape are less likely to occur. The volume of the space to be molded varies somewhat depending on the position where the end seal 141 is attached, but conventionally, the blowing prevention sheet 20, the end seal 141, the first developing frame 131, There is no large variation like the gap formed by the two developing frame bodies 132. Therefore, it is not necessary to prepare a large buffer for applying the coating material as in the prior art, and the space of the buffer 144a can be saved.

  On the other hand, as shown in FIG. 9, the second developing frame 132 is provided with ribs 132d. Specifically, the rib 132d is formed on a surface that is brought into contact with the fixed surface 131c of the first developing frame 131. In the second developing frame 132 and the first developing frame 131, the rib 132d is in contact with the fixed surface 131c, and a horn is applied to the surface of the second developing frame 132 that faces the surface on which the rib 132d is formed. Then, heat is generated by ultrasonic waves, and the rib 132d is melted to be fixed. That is, the second developing frame 132 is fixed to the fixing surface 131c of the first developing frame 131 by the melted rib 132d. Further, the rib 132d is continuously formed so as to extend to the sheet sticking surface 132a through a position facing the seal member 144 when the first developing frame 131 and the second developing frame 132 are welded. Yes. As a result, when the first developing frame 131 and the second developing frame 132 are welded, the rib 132d comes into contact with the seal member 144 with a predetermined penetration amount. That is, in the rib 132d, the portion facing the fixed surface 131c functions as a welding rib to weld the first developing frame 131 and the second developing frame 132, and the portion facing the seal member 144 functions as a seal crushing rib. doing.

  In the switching portion where the functions of the welding rib and the seal crushing rib are switched, the seal member 144 is arranged with respect to the fixed surface 131c of the first developing frame 131 as shown in FIGS. Are formed so as to have substantially the same surface. That is, one end of the seal member 144 is embedded in the fixed surface 131c. As a result, the seal member 144 is not sandwiched between the first developing frame 131 and the second developing frame 132 at a high pressure, so that stable welding of the first developing frame 131 and the second developing frame 132 is maintained. I can do it. Further, the rib 132d facing the seal member 144 is provided in the recess in the second developing frame 132, and is configured to allow the seal member 144 to have a certain thickness. For this reason, even if the rib 132d enters the seal member 144, stable welding of the first developing frame 131 and the second developing frame 132 can be maintained without receiving an excessive repulsive force.

  With the above configuration, the gap between the first developing frame 131 and the second developing frame 132 is sealed, and toner leaks from between the first developing frame 131 and the second developing frame 132. Can be prevented.

  Next, the sealing of the gap between the blowout prevention sheet 20 and the seal member 144 will be described. 10 is a view showing a state after the first developing frame 131 and the second developing frame 132 are welded, and FIG. 11 is a view showing an XX cross section in FIG. As shown in FIGS. 10 and 11, the welded seal member 144 is arranged with a predetermined protrusion amount h from the seal application surface 132 a in a direction perpendicular to the seal application surface 132. Here, the predetermined protrusion amount h is set in consideration of the dimensional variation of each component, the molding dimensional variation of the seal member 144, seal deformation at the time of frame welding, and the like. As for the protrusion amount h, there are harmful effects when the value is too small and when it is too large. For example, when the protrusion amount h is too small, when the blowout prevention sheet 20 is attached, the blowout prevention sheet 20 and the seal member 144 may not be in close contact with each other and a gap may be opened. Therefore, the lower limit value of the protrusion amount h is preferably set to about 0.3 mm as a value for obtaining good adhesion, but if stable adhesion can be obtained even if it is 0.3 mm or less. However, it is not limited to this value. On the other hand, when the protrusion amount h is too large, when the blowout prevention sheet 20 is attached, the blowout prevention sheet 20 may be wavy from the close contact portion with the seal member 144 as a starting point. When undulation occurs in the blowout prevention sheet 20, a gap may be generated at a contact portion with the developing roller 25, and toner may leak. Therefore, it is desirable to set the upper limit value of the protrusion amount h to about 0.6 mm as a value that can be suppressed to a wavy level that does not generate a gap, but even if it is 0.6 mm or more, the waviness can be suppressed to an allowable level. If there is, it is not limited to this value.

  Thus, it is desirable that the protruding amount h of the seal member 144 be within a range of about 0.3 to 0.6 mm. However, in consideration of all the dimensional variations of each component, the molding dimensional variations of the seal member 144, seal deformation at the time of frame welding, and the like, the actual protrusion amount h may not be within this range. Therefore, in this embodiment, the seal member 144 is melted by applying heat to the portion protruding from the sheet application surface, and the protrusion amount h from the sheet application surface 132a is smaller than before the heat is applied. The amount h is within an appropriate range. Specifically, as shown in FIG. 12, the horn 146 is penetrated to a predetermined height with respect to the seal member 144, heated by ultrasonic waves, and the surface is melted. The amount of protrusion h2 is adjusted. When the blowout prevention sheet 20 is attached in this state, as shown in FIG. 1, the blowout prevention sheet 20 is in a stable contact with the seal member 144 having an appropriate protrusion amount h2 without being greatly undulated. Become.

(Adhesion between the blowout prevention sheet and the seal member)
Here, the blowout prevention sheet 20 is in contact with the seal member 144, and even in this state, toner leakage from between the blowout prevention sheet 20 and the seal member 144 can be prevented to some extent. However, the surface of the seal member 144 has irregularities, the boundary between the end seal 141 and the seal member 144, and the double-faced tape 120 for attaching the blowout prevention sheet 20 has a step or the like. In this way, there are cases where factors that prevent good adhesion remain, and there is a possibility that the toner may slightly leak from a minute gap generated by such factors. Therefore, in this embodiment, in order to further improve the toner sealing performance, the sealing member 144 is melted by applying heat to the sealing member 144 via the blowing prevention sheet 20, thereby sealing the minute gap due to the above-described factors. And close contact. Specifically, as shown in FIG. 14, the horn 147 is pressed from the boundary between the seal member 144 and the end seal 141 onto the sheet application surface 132a from above the blowing prevention sheet 20, and an ultrasonic wave is applied to generate heat. . As a result, the blowout prevention sheet 20 and the seal member 144 are more closely attached, and at the same time, the molten resin flows into a minute step generated at the boundary between the seal member 144 and the end seal 141 to seal the gap. In addition, the molten resin flows into even a minute step with the double-sided tape 120 and the gap is sealed, and at the same time, the adhesion of the double-sided tape 120 to the sheet sticking surface 132a is also improved, so the toner sealing property is improved. To do.

  As described above, the seal structure using the seal member 144 seals the gaps generated between the end seal 141, the blowout prevention sheet 20, the first developing frame 131, and the second developing frame 132, and causes toner leakage. Can be prevented. And according to the structure which concerns on a present Example, since application materials, such as the conventional sponge seal | sticker and hot melt, can be replaced by the sealing member 144, it is possible to reduce the number of parts. In addition, this makes it possible to reduce the process of assembling a soft object such as a sponge seal, which has conventionally required strict device management, and thus improves productivity. In addition, since the process of applying hot melt and other coating materials has been abolished, the phenomenon of hot melt and the like becoming thread-like and sticking to the product does not occur. Eliminates the need to improve productivity. Furthermore, in the configuration using the seal member 144 formed by molding with a mold, the buffer 144a can be made smaller than the configuration using the conventional coating material, so that the space of the product can be saved.

  As described above, it is possible to provide a developing device having a seal configuration capable of stable production, a developing cartridge having the same, and a process cartridge while reducing the number of parts and saving space.

1, 1a, 1b, 1c, 1d Photosensitive drum 2, 2a, 2b, 2c, 2d Charging roller 4, 4a, 4b, 4c, 4d Developing unit 6, 6a, 6b, 6c, 6d Cleaning member 7 Elastic member 8 Cleaning Support member 10, 11 Drum bearing 12, 13 Developing bearing 20 Blowing prevention sheet 25, 25a, 25b, 25c, 25d Developing roller 26, 26a, 26b, 26c, 26d Cleaning unit 27 Cleaning frame body 28 Charging roller bearing 31 Developing frame body 35 Development blade 70, 70a, 70b, 70c, 70d Process cartridge 100 Image forming apparatus 120 Double-sided tape 131 First development frame body 132 Second development frame body 133 Toner supply opening 141 End seal 142 Blade lower seal 143 Gap 144 Seal member 144a Ffa 145 mold 146, 147 horn

Claims (10)

A developing device used in an image forming apparatus,
A developer carrier for supplying a developer to the image carrier;
A first developing frame provided with an opening for supplying a developer to the developer carrying member;
A second developing frame fixed to a fixed surface of the first developing frame;
When the developer carrier is disposed so as to overlap the opening, an end that seals a gap between the first developer frame and the developer carrier at the longitudinal end of the developer carrier Part seal,
With
A seal member formed integrally with the first developing frame and connected to the end seal, wherein the sealing member seals between the first developing frame and the second developing frame;
A developing device comprising: The first developing frame further includes a blowing prevention sheet having one end fixed to the sheet sticking surface of the second developing frame and the other end in contact with the developer carrier.
2. The development according to claim 1, wherein the seal member is formed so as to protrude from the sheet sticking surface in a direction perpendicular to the sheet sticking surface before the blowing prevention sheet is attached. apparatus. The sealing member seals a gap formed between the first developing frame, the second developing frame, the end seal, and the blowout prevention sheet;
The developing device according to claim 2. Before attaching the blowout prevention sheet, the seal member is melted by applying heat to the portion protruding from the sheet application surface, and the amount of protrusion from the sheet application surface is smaller than that before applying heat. ,
The developing device according to claim 2, wherein:   5. The developing device according to claim 1, wherein the blowout prevention sheet and the seal member are brought into close contact with each other by applying heat through the blowout prevention sheet to melt the seal member.   The developing device according to claim 1, wherein the second developing frame has a rib that enters the seal member.   The developing device according to claim 6, wherein the rib is continuously formed up to a surface facing the fixed surface.   The developing device according to claim 7, wherein the fixing surface of the first developing frame and the second developing frame are integrated by melting the rib.   A developing cartridge comprising the developing device according to claim 1.   A process cartridge comprising the developing device according to claim 1.

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