Developing device and image forming apparatus

Abstract

The present invention provides a developer and an image forming apparatus. The developer includes: a housing for containing developer; a cover member covering an opening in the upper part of the housing; a developer holding member supported by the housing and holding the developer on an outer surface for rotation; a limiting member disposed opposite to the developer holding member and limiting the amount of developer on the outer surface; a first discharge path inclined toward the interior of the housing and discharging air from the interior of the housing to the exterior of the cover member; and a second discharge path connecting the first discharge path and a filter member disposed on the cover member starting from the first discharge path, the filter member preventing the passage of developer while allowing air to pass through.

Description

Technical Field

[0001] This invention relates to a developer and an image forming apparatus. Background Technology

[0002] An image forming apparatus is known, comprising: an image carrier having a latent image on its surface; and a developer for developing the latent image, wherein the developer has: a developer container having a developer inside; a developer carrier having a surface bearing the developer in the developer container; an opening in the developer container being provided in the developer container to expose a portion of the surface of the developer carrier to the outside of the developer container; and a developer carrier driving device for moving the surface of the developer carrier between the inside and the outside of the developer container, and in an image forming apparatus configured such that the developer carrier is movable between a developing position opposite to the image carrier and a non-developing position other than the developing position, an internal pressure rise prevention device is provided to prevent the internal pressure in the developer container from rising (Patent Document 1).

[0003] Another known developer includes: a developer carrier that carries developer on a surface and the surface moves to supply developer to a latent image on the surface of the latent image carrier in a developing area opposite to the latent image carrier; a developer delivery member that applies a delivery force to developer in a developer container that contains developer supplied to the developer carrier by rotation; a pressure relief opening that discharges gas in the developer container to the outside of the device and suppresses the rise of gas pressure in the developer container; and a filter member disposed at the pressure relief opening to suppress the discharge of developer from the pressure relief opening. The developer further includes a developer movement path blocking member that blocks the movement path of developer bounced up by the rotation of the developer delivery member toward the filter member (Patent Document 2).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2004-045942

[0007] Patent Document 2: Japanese Patent Application Publication No. 2014-178661 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] This invention saves space, suppresses the accumulation of turbid toner in the airflow path, and stabilizes the internal pressure in the developer container.

[0010] Methods for solving problems

[0011] A first aspect of the present invention is a developer comprising:

[0012] The casing, which contains the developer;

[0013] A cover component that covers the opening at the top of the housing;

[0014] A developer holding component, which is supported by the housing and holds the developer on the outer surface and rotates;

[0015] A limiting component, which is configured opposite to the developer holding component, and limits the amount of developer on the outer surface;

[0016] A first discharge path, inclined toward the interior of the housing, discharges air from inside the housing to the exterior of the cover member; and

[0017] A second discharge path connects the first discharge path and a filter component disposed on the cover component starting from the first discharge path. The filter component prevents the developer from passing through while allowing air to pass through.

[0018] The second aspect of the present invention is a developer according to the first aspect, characterized in that,

[0019] The limiting member includes: a limiting portion opposite to the developer holding member, having a predetermined gap between the limiting portion and the developer holding member; a mounting portion intersecting the limiting portion and extending from the limiting portion; a guide portion intersecting the mounting portion and extending obliquely toward the interior of the housing; and the first discharge path being the gap between the upper surface of the guide portion and the inner surface of the cover member, which are opposite to each other.

[0020] The third aspect of the present invention is a developer according to the second aspect, characterized in that,

[0021] The first discharge path is inclined at an angle greater than the angle of repose of the toner contained in the developer.

[0022] The fourth aspect of the present invention is a developer according to the third aspect, characterized in that,

[0023] The upper surface of the guide portion is surface treated to prevent the toner from adhering to the upper surface of the guide portion.

[0024] The fifth aspect of the present invention is a developer according to any one of the first to fourth aspects, characterized in that,

[0025] The second discharge path is the gap between the outer surface of the cover component and the inner surface of the filter component, which is inclined along the first discharge path.

[0026] The sixth aspect of the present invention is a developer according to the fifth aspect, characterized in that,

[0027] The second discharge path is inclined at an angle greater than the angle of repose of the toner contained in the developer.

[0028] The seventh aspect of the present invention is a developer according to the fifth or sixth aspect, characterized in that,

[0029] The second discharge path is configured such that the gap between the outer surface of the cover component and the inner surface of the filter component is widened at an angle.

[0030] The eighth aspect of the present invention is a developer according to any one of the fifth to seventh aspects, characterized in that,

[0031] The outer surface of the cover component is surface treated to prevent the toner from adhering to the outer surface of the cover component.

[0032] The ninth aspect of the present invention is a developer according to any one of the first to eighth aspects, characterized in that,

[0033] The filter component is configured at an angle to close the second discharge path.

[0034] The tenth aspect of the present invention is a developer according to the ninth aspect, characterized in that,

[0035] The filter component is attached to the cover component with double-sided tape.

[0036] The eleventh aspect of the present invention is a developer according to any one of the second to tenth aspects, characterized in that,

[0037] A first sealing member is disposed between the mounting portion of the limiting member and the cover member to cut off the air flowing in from the first discharge path.

[0038] The twelfth aspect of the present invention is a developer according to the eleventh aspect, characterized in that,

[0039] Between the mounting portion of the limiting member and the cover member, a second sealing member is disposed to cut off the airflow generated by the rotation of the developer holding member. On the cover member, an opening for connection to the outside is provided in the area surrounded by the first sealing member and the second sealing member.

[0040] The thirteenth aspect of the present invention is a developer according to any one of the first to twelfth aspects, characterized in that...

[0041] The housing includes: a first circulation path that conveys the received developer while stirring; and a second circulation path that conveys the stirred developer to the developer holding member while conveying it, and the first discharge path is connected to the second circulation path.

[0042] The fourteenth aspect of the present invention is a developer according to the thirteenth aspect, characterized in that,

[0043] The first discharge path is formed on the terminal side of the conveying direction of the second circulation path.

[0044] To address the aforementioned problems, a fifteenth aspect of the present invention provides an image forming apparatus, characterized by comprising:

[0045] An image holder having an electrostatic latent image formed on its surface; and a developer according to any one of the first to fourteenth aspects, which supplies toner to the electrostatic latent image formed on the surface of the image holder to develop the electrostatic latent image.

[0046] Invention Effects

[0047] According to the first and fifteenth aspects, space can be saved, the accumulation of turbid toner in the airflow path can be suppressed, and the internal pressure in the developer container can be stabilized.

[0048] According to the second aspect, it is possible to suppress the temperature rise of the limiting component.

[0049] According to the third and fourth aspects, it is possible to suppress the accumulation of turbid toner in the airflow path.

[0050] According to the fifth aspect, it is possible to expand the surface area of ​​the filter in contact with air to effectively capture turbid toner and inhibit the accumulation of turbid toner.

[0051] According to the sixth aspect, it can suppress the accumulation of turbid toner in the airflow path.

[0052] According to the seventh aspect, it is capable of storing turbid toners.

[0053] According to the eighth aspect, it is possible to suppress the accumulation of turbid toner in the airflow path.

[0054] According to the ninth aspect, space in the developer unit can be saved.

[0055] According to the tenth aspect, it can save space in the developer and is easy to assemble.

[0056] According to aspects eleven and twelfth, it is possible to suppress the intake and discharge of air containing turbid toner from the first discharge path.

[0057] According to aspects thirteen and fourteen, the amount of turbid toner discharged can be reduced. Attached Figure Description

[0058] The embodiments of the present invention will be described in detail with reference to the following accompanying drawings, wherein:

[0059] Figure 1 This is a cross-sectional schematic diagram showing an example of the general structure of an image forming apparatus.

[0060] Figure 2 This is a cross-sectional schematic diagram showing the main part of the image forming section, which includes the photoreceptor unit and the developer.

[0061] Figure 3 This is a top-view cross-sectional diagram showing the ABC line illustrating the delivery of developer in the developer tank.

[0062] Figure 4 This is a cross-sectional schematic diagram showing the structure of the developer.

[0063] Figure 5A yes Figure 4 The enlarged view of the part represented by symbol A shows the structure of the discharge path and labels the symbols associated with the first discharge path.

[0064] Figure 5B yes Figure 4 The enlarged view of the part represented by symbol A shows the structure of the discharge path and labels the symbols related to the second discharge path.

[0065] Figure 6 It is a schematic cross-sectional diagram illustrating the flow of air and the movement of turbid toner in the developer.

[0066] Figure 7 This is a plan view schematically showing the configuration of the first discharge path and opening in the developer using dashed lines.

[0067] Figure 8 This is a schematic cross-sectional view showing the airflow and movement of turbid toner in a comparative example developer in which no opening for connection to the outside is provided on the cover component. Detailed Implementation

[0068] The present invention will now be described in more detail with reference to the accompanying drawings, embodiments, and specific examples, but the present invention is not limited to these embodiments and specific examples.

[0069] Additionally, it should be noted that the accompanying drawings are schematic in the following explanation of their use, and the scale of each dimension may differ from the actual figures. For ease of understanding, some parts other than those required for the explanation have been omitted.

[0070] Furthermore, for ease of understanding of the following explanation, in the accompanying drawings, the front-back direction is set as the X-axis direction, the left-right direction as the Y-axis direction, and the up-down direction as the Z-axis direction.

[0071] (1) Overall structure and operation of the image forming apparatus

[0072] (1.1) Overall structure of the image forming apparatus

[0073] Figure 1 This is a cross-sectional schematic diagram showing an example of the general structure of the image forming apparatus 1 of this embodiment.

[0074] The image forming apparatus 1 includes an image forming unit 10, a paper feeding device 20 disposed at one end of the image forming unit 10, a paper discharge unit 30 disposed at the other end of the image forming unit 10 and discharging printed paper, and an image processing unit 40 (not shown) that generates image information based on printing information sent from a host device.

[0075] The image forming unit 10 includes a system control device 11 (not shown), an exposure device 12, a photosensitive unit 13, a developer 14, a transfer device 15, paper feeding devices 16a, 16b, 16c, a fixing device 17, and a driving device 18 (not shown). It forms the image information received from the image processing unit 40 as a toner image on the paper P fed from the paper feeding device 20.

[0076] The paper feeding device 20 supplies paper to the image forming unit 10. That is, the paper feeding device 20 has multiple paper loading units for accommodating different types of paper (e.g., material, thickness, paper size and texture), and is configured to supply paper P delivered from any of the paper loading units to the image forming unit 10.

[0077] The paper discharge unit 30 discharges the paper from which the image is output by the image forming unit 10. Therefore, the paper discharge unit 30 has a paper discharge receiving unit for discharging the paper after image output. The paper discharge unit 30 may also have the function of post-processing such as cutting and binding (stitching) the bundle of paper output from the image forming unit 10.

[0078] (1.2) Structure and operation of the image forming unit

[0079] In the image forming apparatus 1 with this configuration, paper delivered from the paper loading section of the paper feeding device 20, which is designated for each printed page in the printing job, is fed into the image forming section 10 according to the time of image formation.

[0080] The photosensitive units 13 are arranged parallel to each other below the exposure device 12, and each has a photosensitive drum 31 that serves as an image holder driven by rotation. The charging roller 32, the exposure device 12, the developer 14, the primary transfer roller 52, and the cleaning blade 34 are arranged along the rotation direction of the photosensitive drum 31.

[0081] The developer unit 14 has a developing housing 41 that contains developer. A developing roller 42 (an example of a developer holding member) is disposed inside the developing housing 41 opposite to the photosensitive drum 31. A limiting member 45 (see reference) is disposed near the developing roller 42 to limit the thickness of the developer layer. Figure 2 ).

[0082] Apart from the developer contained in the developer housing 41, each developer 14 has a substantially identical construction, and each of them produces toner images in yellow (Y), magenta (M), cyan (C), and black (K).

[0083] Above the developer 14 are replaceable toner cartridges T for containing developer (toner containing a carrier) and a developer supply device 100 for supplying developer from each toner cartridge T to the developer 14. In this embodiment, the yellow (Y), magenta (M), and cyan (C) toner cartridges Ty, Tm, and Tc, and the two black (K) toner cartridges Tk are removable.

[0084] The surface of the rotating photosensitive drum 31 is charged by the charging roller 32, and the electrostatic latent image is formed by latent image forming light emitted from the exposure device 12. The electrostatic latent image formed on the photosensitive drum 31 is developed into a toner image by the developing roller 42.

[0085] The transfer apparatus 15 includes: an intermediate transfer belt 51 that performs multiple transfers of toner images formed on the photosensitive drums 31 of each photosensitive unit 13; a primary transfer roller 52 that sequentially transfers (primarily transfers) the toner images formed on each photosensitive unit 13 onto the intermediate transfer belt 51; and a secondary transfer roller 53 that transfers (secondarily transfers) the toner images superimposed on the intermediate transfer belt 51 onto the paper P, which serves as the recording medium.

[0086] The toner images formed on the photosensitive drums 31 of each photosensitive unit 13 are electrostatically transferred (single transfer) onto the intermediate transfer belt 51 by a primary transfer roller 52, which is subjected to a specified transfer voltage by a power supply device (not shown) controlled by the system control device 11, to form an overlapping toner image with various toners.

[0087] The overlapping toner image on the intermediate transfer belt 51 is conveyed to the secondary transfer section TR as the intermediate transfer belt 51 moves. In the secondary transfer section TR, the secondary transfer roller 53 is pressed onto the support roller 65 via the intermediate transfer belt 51.

[0088] When the overlay toner image is conveyed to the secondary transfer section TR, paper is supplied to the secondary transfer section TR from the paper feeder 20 at the same time. Then, a preset secondary transfer voltage is applied from the power supply device controlled by the system control device 11 to the support roller 65, which is opposite to the secondary transfer roller 53 via the intermediate transfer belt 51, thereby transferring the multiple toner images on the intermediate transfer belt 51 onto the paper.

[0089] Residual toner on the surface of the photosensitive drum 31 is removed by the cleaning scraper 34 and recycled in a waste toner container (not shown). The surface of the photosensitive drum 31 is then recharged by the charging roller 32.

[0090] The fixing device 17 has an annular fixing belt 17a that rotates in one direction and a pressure roller 17b that contacts the peripheral surface of the fixing belt 17a and rotates in one direction. An engagement portion (fixing area) is formed by the pressing area of ​​the fixing belt 17a and the pressure roller 17b.

[0091] In the transfer device 15, the paper with the toner image transferred is fed to the fixing device 17 via the paper feed device 16a while the toner image is not fixed. The paper fed to the fixing device 17 is fixed with the toner image by a pair of fixing belts 17a and pressure rollers 17b under the action of pressing and heating.

[0092] The fixed paper is fed into the paper output section 30 via the paper feed device 16b.

[0093] In the case of double-sided image output on paper, the paper is flipped by the paper feed device 16c and fed back into the secondary transfer unit TR in the image forming unit 10. Then, after the toner image is transferred and the transferred image is fixed, the paper is fed into the paper discharge unit 30. The paper fed into the paper discharge unit 30 is then discharged into the paper discharge receiving unit after post-processing such as cutting and binding (stitching) as needed.

[0094] (2) Structure and movement of the main parts

[0095] Figure 2 This is a cross-sectional schematic diagram showing the main part of the image forming section 10, which includes the photoreceptor unit 13 and the developer 14. Figure 3 This is a top-view cross-sectional diagram showing the transport of developer in developer 14 along line ABC. Figure 4This is a cross-sectional schematic diagram showing the structure of the developer 14. Hereinafter, the structure and operation of the main parts of the image forming unit 10 will be described with reference to the accompanying drawings.

[0096] (2.1) Structure of the photoreceptor unit

[0097] In the photosensitive unit 13, the photosensitive drum 31 is rotatably supported on the unit housing 35. Inside the unit housing 35 are arranged a charging roller 32, a cleaning roller 33, a cleaning scraper 34, and a screw conveyor 36 that conveys the toner removed by the cleaning scraper 34 to a waste toner recycling container (not shown).

[0098] (2.2) Structure and operation of the developer

[0099] like Figure 2 As shown, in the developer 14, the developing roller 42 is rotatably supported on the developing housing 41. A stirring screw pusher 43A, a supply screw pusher 43B, and a limiting member 45 are disposed within the developing housing 41. The stirring screw pusher 43A and the supply screw pusher 43B within the developing housing 41 are surrounded by developer and are sealed by a cover member 44.

[0100] The developing roller 42 is disposed opposite to the outer peripheral surface of the photosensitive drum 31 through an opening 41a formed in the developing housing 41. The developing roller 42 is formed in a cylindrical shape and extends along the direction from the front to the rear of the image forming apparatus 1. Figure 4 (As shown) Extension. In addition, the developing roller 42 includes: a cylindrical developing sleeve 42A, which is rotatably supported relative to the developing housing 41; and a magnet 42B, which is a cylindrical magnet component, disposed in the internal space of the developing sleeve 42A and fixed relative to the developing housing 41.

[0101] The developing sleeve 42A is configured to hold the developer on its outer peripheral surface using the magnetic force of the magnet 42B, and the developer is held in place by the rotation of the developing sleeve 42A. Figure 2 (As indicated by arrow B) the developer is delivered and supplied to the electrostatic latent image of the photosensitive drum 31.

[0102] In addition, the developer 14 is provided with a stirring screw pusher 43A and a supply screw pusher 43B that simultaneously stirs and delivers developer. Figure 3 This is a cross-sectional schematic diagram taken horizontally along line ABC to illustrate the delivery (movement) of the developer in the developer unit 14. Inside the developer housing 41, a partition wall 41b is erected between the stirring screw pusher 43A and the supply screw pusher 43B, dividing the developer housing 41 into two developer receiving portions 41A and 41B, and openings 41C and 41D are formed at the longitudinal ends of the partition wall 41b, respectively.

[0103] The stirring screw pusher 43A and the supply screw pusher 43B receive rotational force from a drive source (not shown) and rotate along the inner wall of the developer containers 41A and 41B to deliver the developer in the developer containers 41A and 41B in a predetermined direction.

[0104] Specifically, the stirring screw pusher 43A stirs the developer in the developer container 41A while conveying the developer in the direction of arrow (-Y) (front side), which is the first circulation path. The supply screw pusher 43B conveys the developer in the developer container 41B while conveying the developer in the direction of arrow (Y) (rear side), which is the second circulation path. The developer conveyed in the direction of arrow (-Y) moves from the opening 41C to the developer container 41B, and the developer conveyed in the direction of arrow (Y) moves from the opening 41D to the developer container 41A.

[0105] As a result, the developer inside the developing housing 41 circulates while being agitated by the stirring screw pusher 43A and the supply screw pusher 43B. The toner in the developer becomes charged through this agitation.

[0106] like Figure 4 As shown, in the developer 14, a limiting member 45 is provided above the developing roller 42.

[0107] The limiting member 45 has a predetermined gap with the developing roller 42, which restricts the movement of a portion of the developer held on the surface of the developing roller 42, thereby setting the thickness of the developer held on the surface of the developing roller 42 to a predetermined thickness.

[0108] Next, the magnet 42B disposed inside the developing sleeve 42A will be described. The magnet 42B has five magnetic poles arranged along its circumference: N1 to N3 (N poles), S1, and S2 (S poles). Magnetic pole N2 (pickup pole) attracts the developer delivered by the supply screw pusher 43B and attaches it to the surface of the developing sleeve 42A. Magnetic pole S2 (trimming pole) is opposite to the limiting member 45, holding the developer trimmed to a predetermined layer thickness by the limiting member 45. Magnetic poles N3 and N1 act as transport poles, causing the developer on the developing sleeve 42A to move downstream in the rotational direction of the developing sleeve 42A.

[0109] Magnetic pole S1 is positioned opposite to the photosensitive drum 31, and the developer supplied from magnetic pole N1 is held in place by the rotation of the developing sleeve 42A. An electric field is created by applying a developing bias voltage between the developing sleeve 42A and the photosensitive drum 31, causing the toner in the developer to move towards the photosensitive drum 31. The carrier in the developer is held by magnetic pole S1, inhibiting its adhesion to the photosensitive drum 31. The stripping pole, together with adjacent magnetic poles N2 and N3 of the same polarity, forms a repulsive magnetic field, causing the developer on the developing sleeve 42A, where the toner has been consumed during development, to detach from the developing sleeve 42A.

[0110] (2.3) Structure and function of the discharge path

[0111] Figure 5A and 5B yes Figure 4 The enlarged view of the part represented by symbol A shows the structure of the discharge path. Figure 6 This is a schematic cross-sectional view showing the flow of air and the movement of the turbid toner ct in the developer 14. Figure 5A Label the symbols related to the first row of road 46. Figure 5B Label the symbols associated with the second discharge path 47 to show the structure of the discharge path.

[0112] In the developer 14, an air discharge path is provided on the cover member 44 for discharging air from the inside of the developer housing 41 to the outside of the developer housing 41. In addition, a filter member 48 is provided at the part of the discharge path that connects to the outside, which captures the cloudy toner ct in the air flowing in the discharge path and being discharged.

[0113] In this embodiment, the discharge route is configured as follows: a first discharge route 46, which is formed at an angle toward the interior of the developing housing 41 and discharges air from the interior of the developing housing 41 to the exterior of the developing housing 41; and a second discharge route 47, which is connected to the first discharge route 46 and connected to a filter component 48 disposed on the cover component 44 starting from the first discharge route 46 (see reference). Figure 4 ).

[0114] A portion of the limiting member 45 is configured to be opposed to the inner wall surface 44a of the cover member 44 with a gap between them, the gap being the first discharge path 46.

[0115] like Figure 5A As shown, the limiting member 45 comprises: a limiting portion 45A, which is opposite to the developing roller 42 with a predetermined gap; a mounting portion 45B, which intersects with and extends from the limiting portion 45A; and a guide portion 45C, which intersects with the mounting portion 45B and extends obliquely toward the interior of the developing housing 41. The first discharge path 46 is the gap G between the upper surface 45Ca of the guide portion 45C and the inner wall surface 44a of the cover member 44 that closes the opening at the upper part of the developing housing 41.

[0116] The first discharge path 46 is formed obliquely toward the developer container 41B, which is provided with the developer housing 41 and the supply screw pusher 43B. The air inlet 46a of the first discharge path 46 is located above the developer container 41B. In the developer unit 14, while stirring the developer supplied from the toner cartridge T via the developer supply device 100 in the developer container 41A, it is conveyed to and circulated to the developer container 41B, so the amount of cloudy toner in the developer container 41B is less than the amount of cloudy toner in the developer container 41A. Therefore, in this embodiment, by arranging the air inlet 46a toward the developer container 41B, the amount of cloudy toner ct contained in the air discharged from the first discharge path 46 is reduced.

[0117] Additionally, the guide portion 45C in the first discharge path 46 has an angle Θ greater than the angle of repose of the toner contained in the developer. Figure 5A (As shown) They are arranged at an angle, forming a descending slope. The angle of repose of the toner varies depending on the type of developer, temperature, humidity, and other environmental factors.

[0118] Therefore, as Figure 6 As shown, even if the cloudy toner ct adheres to the upper surface 45Ca of the guide portion 45C of the limiting member 45, the toner adhering to it will slide off (see reference). Figure 6 (Middle arrow R2), thus it is possible to suppress the accumulation of toner on the upper surface 45Ca of the guide portion 45C.

[0119] The upper surface 45Ca of the guide portion 45C can be surface-treated to prevent the toner from adhering to the upper surface 45Ca. Examples of surface treatments include flame treatment, corona treatment, plasma treatment, polishing treatment, roughening treatment, active energy ray irradiation treatment, ozone treatment, surfactant treatment, silane coupling treatment, etc. These treatments can also be combined. In addition, fluororesin tape can be adhered to the upper surface 45Ca. This suppresses the accumulation of toner on the upper surface 45Ca of the guide portion 45C.

[0120] The airflow direction of the first row of outlet 46 (refer to) Figure 6 The outlet 46b on the downstream side of the middle arrow (R0) is connected to the second discharge outlet 47.

[0121] like Figure 5B As shown, the outer surface 44b of the cover member 44 and the inner surface 48a of the filter member 48 are positioned opposite each other with a gap, which forms a second discharge path 47 that slopes along the first discharge path 46. That is, like the first discharge path 46, the outer surface 44b faces each other at an angle Θ greater than the angle of repose of the toner contained in the developer. Figure 5B(As shown) It is arranged at an angle in a descending slope manner. As a result, it is possible to suppress the accumulation of toner on the outer surface 44b of the cover member 44.

[0122] The outer surface 44b of the cover member 44 constituting the second discharge path 47 can be surface-treated to prevent toner from adhering to the outer surface 44b of the cover member 44. Examples of surface treatments include surfactant treatment and application of fluoropolymer-based adhesive tape. This suppresses the accumulation of toner on the upper surface 45Ca of the guide portion 45C.

[0123] like Figure 5B As shown, the second discharge path 47 is formed such that the gap between the outer surface 44b and the inner surface 48a is widened at an angle, and a bag-shaped space S is formed at the lower end of the second discharge path 47. This allows the storage of cloudy toner ct that slides off the outer surface 44b of the cover member 44. The space S is sized such that the stored toner dose will not become full during the replacement interval of the developer 14.

[0124] The air inlet 47a of the second discharge path 47 is connected to the outlet 46b of the first discharge path 46. The outlet 47b of the second discharge path 47 is opposite to the filter component 48, which is provided on the cover component 44 and prevents the passage of developer while allowing air to pass through. Thus, as Figure 6 As shown, the air inside the developer unit 14 flows from the developer container 41B through the first discharge path 46 to the second discharge path 47 (see reference). Figure 6 (middle arrow R0), and discharged to the outside of the developer 14 through the filter component 48 (see reference). Figure 6 (Middle arrow R1).

[0125] The filter component 48 is directly adhered to the upper surface 44a of the cover component 44 using double-sided tape (not shown) to seal the outlet 47b of the second discharge path 47 at the top of the cover component 44. This saves space in the developer 14 and facilitates assembly.

[0126] There are no particular limitations on the material of the filter component 48; polyolefins (PE, PP, etc.), polyamides, polyesters (PET, etc.), aromatic polyamides, or composites of these materials can be used. For example, by using a porous material with a capture efficiency of 25% (particle size of 0.3 to 0.5 micrometers) and a pressure loss of approximately 3 Pa at 10 cm / s, it is possible to prevent the passage of turbid toner ct generated in the developing housing 41 while allowing air to pass through, thereby suppressing the pressure rise in the developing unit 14.

[0127] Figure 8 The diagram schematically illustrates the airflow and movement of the turbid toner ct in a comparative example developer 14A where the cover component does not have an opening for connection to the outside.

[0128] like Figure 8 As shown, in the developer unit 14A, the rotation of the developing roller 42 generates a strong rotating airflow R around the developing roller 42. Due to this rotating airflow R, a negative pressure is generated in the gap between the limiting member 45 and the cover member 44 above the developing roller 42, allowing air flowing in the first discharge path 46 to potentially enter the gap between the limiting member 45 and the cover member 44 (see reference). Figure 8 Middle arrow f).

[0129] In the developer 14 of this embodiment, as Figure 5A and 5B As shown, a first sealing member 49A is disposed between the mounting portion 45B of the limiting member 45 and the cover member 44 to cut off the flow of air from the first discharge passage 46. An example of the first sealing member 49A is a foam sponge. This suppresses the flow of air from the first discharge passage 46.

[0130] In addition, such as Figure 5A and 5B As shown, a second sealing member 49B is disposed between the mounting portion 45B of the limiting member 45 and the cover member 44 to cut off the flow of air of the rotating airflow R generated with the rotation of the developing roller 42. On the cover member 44, an opening 44c for connecting to the outside is provided in the area surrounded by the first sealing member 49A and the second sealing member 49B. A plurality of openings 44c are provided in the axial direction of the developing roller 42.

[0131] Thus, after sealing the space between the mounting portion 45B of the limiting member 45 and the cover member 44 using the first sealing member 49A, an opening 44c is provided on the cover member 44 to connect to the outside and open to the atmosphere (see reference). Figure 6 (Center arrow F) thereby inhibits the air containing the turbid toner ct from being drawn out from the first exhaust path 46.

[0132] Figure 7 The configuration of the first discharge path 46 and the opening 44c in the developer 14 is schematically shown with dashed lines.

[0133] like Figure 7 As shown, the first discharge path 46 is connected to the developer container 41B of the second circulation path, which serves as a supply spiral pusher 43B that conveys the developer backward (in the direction of arrow (Y)) while stirring. The first discharge path 46 is formed at the terminal side (rear side) of the developer container 41B in the conveying direction of the second circulation path. That is, air is discharged from an area where less cloudy toner ct is generated in the developer 14. This reduces the amount of cloudy toner ct discharged.

[0134] In addition, such as Figure 7As shown, the opening 44c is provided at two positions above the developing roller 42, on the front and rear sides. This suppresses the negative pressure generated by the rotation of the developing roller 42 in the axial direction of the developing roller 42.

[0135] In this embodiment, the case where the limiting member 45 is disposed above the developing roller 42 is described as an example, but the limiting member 45 may also be disposed below the developing roller 42. In this case, for forming the first discharge path 46, a portion of the limiting member 45 is not used, but instead a plate member (not shown) that can be disposed to have a gap with the inner surface of the cover member 44 is disposed.

[0136] The description of the above-described embodiments of the invention has been provided for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations will obviously be apparent to those skilled in the art. The above-described embodiments were chosen and described in order to best explain the principles of the invention and its practical application, thereby enabling others skilled in the art to understand the various embodiments of the invention and various modifications suitable for the intended particular use. The scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A developer characterized by comprising: have: The casing, which contains the developer; A cover component that covers the opening at the top of the housing; A developer holding component, which is supported by the housing and holds the developer on the outer surface and rotates; A limiting component, which is configured opposite to the developer holding component, and limits the amount of developer on the outer surface; The first discharge path is inclined toward the interior of the housing and discharges air from the interior of the housing to the exterior of the cover component; as well as A second discharge path connects the first discharge path and a filter component disposed on the cover component starting from the first discharge path. This filter component prevents the developer from passing through while allowing air to pass through. The limiting member includes: a limiting portion opposite to the developer holding member, having a predetermined gap between the limiting portion and the developer holding member; a mounting portion intersecting the limiting portion and extending from the limiting portion; and a guiding portion intersecting the mounting portion and extending obliquely toward the interior of the housing. The first discharge path is the gap between the upper surfaces of the guide portions and the inner surfaces of the cover components, which are opposite to each other. The second discharge path is the gap between the outer surface of the cover component and the inner surface of the filter component, and it is inclined along the first discharge path.

2. The developer according to claim 1, characterized in that, The first discharge path is inclined at an angle greater than the angle of repose of the toner contained in the developer.

3. The developer according to claim 2, characterized in that, The upper surface of the guide portion is surface treated to prevent the toner from adhering to the upper surface of the guide portion.

4. The developer according to claim 1, characterized in that, The second discharge path is inclined at an angle greater than the angle of repose of the toner contained in the developer.

5. The developer according to any one of claims 1 to 4, characterized in that, The second discharge path is configured such that the gap between the outer surface of the cover component and the inner surface of the filter component is widened at an angle.

6. The developer according to any one of claims 2 to 4, characterized in that, The outer surface of the cover component is surface treated to prevent the toner from adhering to the outer surface of the cover component.

7. The developer according to claim 1, characterized in that, The filter component is configured at an angle to close the second discharge path.

8. The developer according to claim 7, characterized in that, The filter component is attached to the cover component with double-sided tape.

9. The developer according to claim 1, characterized in that, A first sealing member is disposed between the mounting portion of the limiting member and the cover member to cut off the air flowing in from the first discharge path.

10. The developer according to claim 9, characterized in that, Between the mounting portion of the limiting member and the cover member, a second sealing member is disposed to cut off the airflow generated by the rotation of the developer holding member. On the cover member, an opening for connection to the outside is provided in the area surrounded by the first sealing member and the second sealing member.

11. The developer according to claim 1, characterized in that, The housing includes: a first circulation path that conveys the received developer while stirring; and a second circulation path that conveys the stirred developer to the developer holding member while conveying it, and the first discharge path is connected to the second circulation path.

12. The developer according to claim 11, characterized in that, The first discharge path is formed on the terminal side of the conveying direction of the second circulation path.

13. An image forming apparatus characterized by comprising: have: An image holder having an electrostatic latent image formed on its surface; and a developer according to any one of claims 1 to 12, which supplies toner to the electrostatic latent image formed on the surface of the image holder to develop the electrostatic latent image.

Images