Developing cartridge

Abstract

A developing cartridge (2) includes a housing (21), a developing roller (22), a first agitator (25), a supply roller (23), and a second agitator (26). The housing (21) is configured to house toner. The developing roller (22) is rotatable about a developing roller rotation axis (22A) extending in a first direction. The first agitator (25) is configured to agitate the toner. The first agitator (25) is rotatable about a first agitator rotation axis (25A) extending in the first direction. The supply roller (23) is located between the first agitator (25) and the developing roller (22). The supply roller (23) is rotatable about a supply roller rotation axis (23A) extending in the first direction. The second agitator (26) is located between the supply roller and the first agitator (25). The second agitator (26) is rotatable about a second agitator rotation axis (26A) extending in the first direction. A rotation locus of the second agitator (26) is located outside a rotation locus of the first agitator (25).

Description

[0001] This application is a divisional application of the following patent application:

[0002] Application Number: 201980001524.3

[0003] Application date: July 1, 2019

[0004] Invention Title: Developing Box Technical Field

[0005] This disclosure relates to a developing cartridge. Background Technology

[0006] Electrophotographic image forming apparatuses, such as LED printers, are conventionally known. These apparatuses typically include a frame housing a photosensitive drum and a developing cartridge that is attached to and detachable from the frame. For example, Japanese Patent Application Publication No. 2018-66973 discloses a conventional image forming apparatus that includes a developing cartridge.

[0007] The developing cartridge disclosed in Japanese Patent Application Publication No. 2018-66973 includes a housing, a developing roller, an agitator, and a supply roller. The housing can contain toner. The developing roller is rotatable about a rotation axis extending in a first direction. The agitator rotates about the rotation axis extending in the first direction to agitate the toner contained in the housing. The agitator is spaced apart from the developing roller in a second direction. The supply roller rotates about the rotation axis extending in the first direction to supply toner to the developing roller. The supply roller is located between the developing roller and the agitator in the second direction.

[0008] [Citation List]

[0009] [Patent Documents]

[0010]

PTL1

[0011] Japanese Patent Application Publication No. 2018-66973. Summary of the Invention

[0012] [Technical Issues]

[0013] However, in the developing cartridge disclosed in Japanese Patent Application Publication No. 2018-66973, there are areas within the housing where the toner cannot be adequately agitated by the rotation of the stirrer alone. For example, when the residual amount of toner in the housing is low, toner stagnation may occur in the area around the supply roller.

[0014] In view of the above, the object of this disclosure is to provide a developing cartridge capable of fully agitating the toner in the internal space of the housing.

[0015] Solution to the problem

[0016] (First Aspect) To achieve the above and other objectives, according to one aspect, this disclosure provides a developing cartridge, comprising: a housing, a developing roller, a first agitator, a supply roller, and a second agitator. The housing is configured to contain toner. The developing roller is rotatable about a developing roller rotation axis extending in a first direction. The first agitator is configured to agitate the toner. The first agitator is rotatable about a first agitator rotation axis extending in the first direction. The supply roller is located between the first agitator and the developing roller. The supply roller is rotatable about a supply roller rotation axis extending in the first direction. The second agitator is located between the supply roller and the first agitator. The second agitator is rotatable about a second agitator rotation axis extending in the first direction. The rotation path of the second agitator is outside the rotation path of the first agitator.

[0017] (Second aspect) In the developing cartridge according to the first aspect, preferably, the outer peripheral surface of the developing roller is in contact with the outer peripheral surface of the supply roller.

[0018] (Third aspect) In the developing cartridge according to the first or second aspect, preferably, the supply roller is located between the first agitator and the developing roller in a second direction connecting the rotation axis of the first agitator and the rotation axis of the developing roller.

[0019] (Fourth aspect) In the developing cartridge according to the third aspect, preferably, the second agitator is located in the second direction between the supply roller and the first agitator.

[0020] (Fifth aspect) In the developing cartridge according to the fourth aspect, preferably, the second agitator is positioned closer to the supply roller in the second direction than the first agitator is closer to the supply roller.

[0021] (Sixth aspect) In a developing cartridge according to any one of the first to fifth aspects, preferably, the rotation direction of the second stirrer is the same as that of the first stirrer.

[0022] (Seventh Aspect) In a developing cartridge according to any one of the first to sixth aspects, preferably: the housing has an end portion in a first direction; the end portion has an outer surface; and the developing cartridge further includes a connector, a developing roller gear, a supply roller gear, a first agitator gear, a second agitator gear, an idler gear, a first drive gear, and a second drive gear. The connector is located at the outer surface. The connector is rotatable about a connector axis extending in the first direction. The connector includes a connector gear portion. The developing roller gear is located at the outer surface. The developing roller gear is rotatable with the developing roller according to the rotation of the connector. The supply roller gear is located at the outer surface. The supply roller gear is rotatable with the supply roller according to the rotation of the connector. The first agitator gear is positioned at the outer surface. The first agitator gear is rotatable with the first agitator. The second agitator gear is located at the outer surface. The second agitator gear is rotatable with the second agitator. The second agitator gear is positioned closer to the outer surface in the first direction than the connector is. At least a portion of the second agitator gear is positioned in the first direction between the connector and the outer surface. The idler gear is rotatable according to the rotation of the connector. The idler gear includes: a first idler gear portion that meshes with a coupling gear portion; and a second idler gear portion positioned in a first direction closer to the outer surface than the first idler gear portion. A first drive gear meshes with the second idler gear portion. The second drive gear meshes with both the first drive gear and the second agitator gear.

[0023] (Eighth Aspect) In a developing cartridge according to any one of the first to sixth aspects, preferably: the housing has an end portion in a first direction; the end portion has an outer surface; and the developing cartridge further includes a connector, a developing roller gear, a supply roller gear, a first agitator gear, a second agitator gear, an idler gear, and an even number of drive gears. The connector is located at the outer surface. The connector is rotatable about a connector axis extending in the first direction. The connector includes a connector gear portion. The developing roller gear is located at the outer surface. The developing roller gear is rotatable with the developing roller according to the rotation of the connector. The supply roller gear is located at the outer surface. The supply roller gear is rotatable with the supply roller according to the rotation of the connector. The first agitator gear is positioned at the outer surface. The first agitator gear is rotatable with the first agitator. The second agitator gear is located at the outer surface. The second agitator gear is rotatable with the second agitator. The second agitator gear is positioned closer to the outer surface in the first direction than the connector is. At least a portion of the second agitator gear is positioned between the connector and the outer surface in the first direction. The idler gear is rotatable according to the rotation of the connector. The idler gear includes: a first idler gear portion that meshes with a coupling gear portion; and a second idler gear portion positioned in a first direction closer to the outer surface than the first idler gear portion. An even number of drive gears are configured to transmit driving force from the second idler gear portion to the second agitator gear.

[0024] (Ninth aspect) In the developing cartridge according to the seventh or eighth aspect, preferably, the connector is rotatable about the connector axis in response to receiving a driving force.

[0025] (Tenth aspect) In the developing cartridge according to any one of the seventh to ninth aspects, it is preferred that: the developing roller includes a developing roller shaft extending in a first direction; and the developing roller gear is attached to the developing roller shaft and rotates together with the developing roller shaft.

[0026] (Eleventh aspect) In the developing cartridge according to any one of the seventh to tenth aspects, it is preferred that: the supply roller includes a supply roller shaft extending in a first direction; and the supply roller gear is attached to the supply roller shaft and is rotatable with the supply roller shaft.

[0027] (Twelfth aspect) In the developing cartridge according to any one of the seventh to eleventh aspects, it is preferred that: the first stirrer includes a first stirrer shaft extending in a first direction; and the first stirrer gear is attached to the first stirrer shaft and is rotatable with the first stirrer shaft.

[0028] (Thirteenth aspect) In the developing cartridge according to any one of the seventh to twelfth aspects, it is preferred that: the second stirrer includes a second stirrer shaft extending in a first direction; and the second stirrer gear is attached to the second stirrer shaft and is rotatable together with the second stirrer shaft.

[0029] (Fourteenth aspect) In the developing cartridge according to any one of the seventh to thirteenth aspects, it is preferred that: the developing cartridge further includes a support member having a flat plate shape extending in both a second direction and a third direction, the third direction intersecting both the first and second directions; the support member having a side portion and a side portion opposite to each other in the first direction, the side portion being positioned further from the outer surface than the other side portion; a coupling is rotatably supported on one side portion of the support member; a developing roller gear and a supply roller gear are located on one side portion of the support member; and a drive gear and a second agitator gear are located on the other side portion of the support member.

[0030] (Fifteenth aspect) In the developing cartridge according to any one of the seventh to fourteenth aspects, it is preferred that: the outer surface has a recessed portion that is recessed in a first direction from one end portion of the housing to the other end portion; and the drive gear and the second agitator gear are accommodated in the recessed portion.

[0031] (Sixteenth aspect) In the developing cartridge according to any one of the first to fifteenth aspects, preferably, the rotational frequency of the second stirrer is greater than the rotational frequency of the first stirrer.

[0032] (Seventeenth aspect) In the developing cartridge according to any one of the first to sixteenth aspects, preferably, the circumferential speed of the second agitator is greater than or equal to the circumferential speed of the supply roller.

[0033] (Eighteenth aspect) In the developing cartridge according to any one of the first to seventeenth aspects, it is preferred that: the first agitator includes a first agitator fin rotatable about a first agitator rotation axis; the second agitator includes a second agitator fin rotatable about a second agitator rotation axis; and the first agitator fin and the second agitator fin do not contact each other.

[0034] (Nineteenth aspect) In the developing cartridge according to the eighteenth aspect, preferably, the first agitator fins are sheet-like films.

[0035] (Twentieth aspect) In the developing cartridge according to the eighteenth or nineteenth aspect, preferably, the second agitator has a polygonal columnar shape, with each of its corner portions serving as a second agitator fin.

[0036] (Twenty-first aspect) In the developing cartridge according to the eighteenth or nineteenth aspect, it is preferred that the second agitator fins include a rotating body and a plurality of fin portions. The rotating body is rotatable about the rotation axis of the second agitator. Each of the plurality of fin portions extends radially outward from the outer peripheral surface of the rotating body.

[0037] (Twenty-second aspect) In a developing cartridge according to any one of aspects eighteen to twenty-first, preferably, the diameter of the second agitator fin relative to the axis of rotation of the second agitator is smaller than the diameter of the first agitator fin relative to the axis of rotation of the first agitator.

[0038] (Twenty-third aspect) In a developing cartridge according to any one of the first to twenty-second aspects, preferably, the supply roller is configured to supply toner to the outer peripheral surface of the developing roller.

[0039] [Beneficial effects of the invention]

[0040] According to the first to twenty-third aspects of this disclosure, the toner can be thoroughly stirred within the internal space of the casing.

[0041] According to a first aspect of the invention, within the internal space of the housing, the toner located in a region where sufficient mixing of the toner cannot be achieved by the rotation of the first stirrer alone can be stirred by the rotation of the second stirrer. Therefore, even if the remaining amount of toner in the internal space of the housing becomes low, sufficient mixing of the toner can still be achieved.

[0042] According to a fifth aspect of this disclosure, the toner retained around the supply roller can be agitated by rotating the second agitator. Therefore, retention of the toner flow within the internal space of the housing can be suppressed.

[0043] According to a sixth aspect of this disclosure, the toner stream formed by the rotation of the second stirrer can be easily incorporated into the toner stream formed by the rotation of the first stirrer. As a result, retained toner can be introduced into the stirring zone of the first stirrer, thereby achieving thorough overall stirring of the toner.

[0044] According to the seventh or eighth aspect of this disclosure, the first agitator and the second agitator can rotate at a constant speed ratio. Furthermore, the first agitator and the second agitator rotate in the same direction of rotation as viewed in the first direction. Therefore, the toner stream formed by agitation with the second agitator can be easily merged with the toner stream formed by agitation with the first agitator. On the other hand, in the region where the outer peripheral surfaces of the second agitator and the supply roller face each other, the rotation directions of the second agitator and the supply roller are the same when viewed in the first direction. As a result, the toner can be easily supplied to the outer peripheral surface of the supply roller by the rotation of the second agitator.

[0045] According to the fourteenth aspect of this disclosure, the developing roller gear, the supply roller gear, the first drive gear, the drive gear, and the second agitator gear can be divided into a side portion and a side portion in a first direction of the support member, and each is disposed at a corresponding side portion of the two side portions. As a result, a high gear layout density can be achieved in a limited space, thereby making the developing cartridge compact.

[0046] According to a fifteenth aspect of the invention, the drive gear and the second agitator gear can be additionally housed in a gearbox with almost no change to the conventional gear layout, such as the layout of the coupling, developing roller gear, and supply roller gear. Therefore, the second agitator of this disclosure can be readily used in a developing cartridge.

[0047] According to a sixteenth aspect of the invention, by rotating the second stirrer, the toner retained in the internal space of the housing can be easily introduced into the stirring zone of the first stirrer.

[0048] According to the seventeenth aspect of this disclosure, insufficient supply of toner to the supply roller can be prevented.

[0049] According to the eighteenth aspect of this disclosure, complex toner flow in the internal space of the housing can be prevented due to interference between the first and second agitator fins, thereby promoting uniform mixing of the toner.

[0050] According to the nineteenth aspect of this disclosure, the tip portion of the first stirrer fins can be bent while acting on the inner surface of the housing due to the rotation of the first stirrer. Therefore, the toner adhering to the inner surface of the housing can be scraped off. As a result, the toner in the housing can be further mixed more evenly.

[0051] According to the twentieth aspect of this disclosure, a second agitator fin with high rigidity can be realized.

[0052] According to aspect twenty-one of this disclosure, the surface area of ​​the second agitator fins can be increased. As a result, the toner retained in the internal space of the housing can be thoroughly agitated by the second agitator fins. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of an image forming apparatus.

[0054] Figure 2 This is a perspective view of a developing cartridge according to an embodiment of the present disclosure.

[0055] Figure 3 This is a view of the developing chamber viewed from a third-party perspective.

[0056] Figure 4 This is a view of the developing chamber as seen from the first direction.

[0057] Figure 5 It is a cross-sectional view of the developing cartridge taken along a plane perpendicular to the first direction.

[0058] Figure 6 This is an exploded stereoscopic view of a part of the developing chamber.

[0059] Figure 7 This is a view of the developing cartridge when viewed in the first direction and with the gearbox removed.

[0060] Figure 8 When observed in the first direction and from Figure 7 The view of the developing cassette with the connector, developing roller gear, and supply roller gear removed.

[0061] Figure 9 When observed in the first direction and from Figure 8 The view of the developing cartridge in the state of removing the idling gear and the first agitator gear.

[0062] Figure 10 When observed in the first direction and from Figure 9 The view of the developing cassette in the state where the support member has been removed.

[0063] Figure 11 When observed in the first direction and from Figure 10 The view of the developing cassette with the first drive gear, second drive gear, and second stirrer gear removed. Detailed Implementation

[0064] Embodiments of this disclosure will be described with reference to the accompanying drawings.

[0065] The developing cartridge 2 according to this embodiment includes a developing roller 22 and a first agitator 25, which will be described in detail later. Here, as... Figure 2 , 3 As shown in Figure 6, the direction in which the developing roller rotation axis 22A of the developing roller 22 extends will be referred to as the "first direction". Furthermore, the direction connecting the developing roller rotation axis 22A and the first agitator rotation axis 25A of the first agitator 25 will be referred to as the "second direction". The second direction intersects the first direction and, preferably, is perpendicular to the first direction. A direction that intersects both the first and second directions will be referred to as the "third direction". Preferably, the third direction is perpendicular to both the first and second directions.

[0066] <1. Image forming apparatus>

[0067] Figure 1This is a schematic diagram of an image forming apparatus 100. The image forming apparatus 100 is an electrophotographic printer. Examples of the image forming apparatus 100 include laser printers and LED printers. Figure 1 As shown, the image forming apparatus 100 includes a main housing 101, a controller 102, a drum unit 1, and four developing cartridges 2. The four developing cartridges 2 can be individually attached to the drum unit 1. Furthermore, the drum unit 1, to which the four developing cartridges 2 are attached, can be attached to the main housing 101 and can be detached from the main housing 101.

[0068] Four developing cartridges 2 contain different colors of developer (e.g., cyan, magenta, yellow, and black) (e.g., toner in this embodiment). The image forming apparatus 100 uses the toner supplied from the four developing cartridges 2 to form an image on the recording surface of the printed sheet. However, the number of developing cartridges 2 to be attached to the drum unit 1 is not limited. One to three developing cartridges 2 or no less than five developing cartridges 2 can be used.

[0069] Figure 1 The controller 102 shown is located within the main housing 101. The controller 102 is constructed, for example, from a circuit board. The controller 102 includes a processor such as a CPU and various memories. The controller 102 is configured to perform various processes of the image forming apparatus 100 via the processor operating according to a program.

[0070] <2. Drum Unit>

[0071] Figure 1 The drum unit 1 shown includes four photosensitive drums 11 and a frame 12. The photosensitive drums 11 are configured to transfer toner supplied from the developing cartridge 2 onto a printing sheet. The four photosensitive drums 11 are arranged at intervals. Each photosensitive drum 11 has a cylindrical outer peripheral surface extending in a first direction. The outer peripheral surface of the photosensitive drum 11 is coated with a photosensitive material. Each photosensitive drum 11 is rotatable about a drum rotation axis extending in the first direction.

[0072] The frame 12 is configured to hold four photosensitive drums 11. The frame 12 includes four cartridge holding portions 120. The four cartridge holding portions 120 are arranged at intervals. Each of the four developing cartridges 2 is attached to a corresponding cartridge holding portion 120.

[0073] <3. Detailed information about the developing cartridge>

[0074] Figure 2 This is a three-dimensional view of developer cartridge 2. Figure 3 This is a view of the developing chamber 2 when viewed from a third-party upward perspective. Figure 4 This is a view of the developing chamber 2 when viewed from one side in the first direction. Figure 5This is a cross-sectional view of the developing cartridge 2 taken along a plane perpendicular to the first direction. For example... Figure 2 and 3 As shown, the developing cartridge 2 includes a housing 21, a developing roller 22, a gearbox 32, and a connector 24. Figure 4 and 5 As shown, the developing cartridge 2 also includes a supply roller 23, a first agitator 25, and a second agitator 26.

[0075] Figure 2 and 3 The casing 21 shown is a container for holding toner. Figure 3 As shown, the housing 21 extends in a first direction between a first outer surface 211 and a second outer surface 212. That is, the housing 21 has one end portion and another end portion in the first direction; the one end portion is located on one side of the first direction and has the first outer surface 211, while the other end portion is located on the other side of the first direction and has the second outer surface 212. The toner can be contained within the internal space of the housing 21. The housing 21 has an opening 214. The opening 214 is located at one end portion of the housing 21 in a second direction. The internal space of the housing 21 communicates with the outside of the housing 21 through the opening 214.

[0076] like Figures 2 to 4 As shown, gearbox 32 is attached to a first outer surface 211 from one side in a first direction to cover the first outer surface 211. Gearbox 32 is secured to the first outer surface 211 by fastening members such as screws. Specifically, a space is defined between the first outer surface 211 and the inner surface of gearbox 32 (i.e., the surface on the other side in the first direction), and this space accommodates the developing roller gear 223, supply roller gear 233, first agitator gear 254, second agitator gear 264, connector 24, idler gear 27, first drive gear 28, and second drive gear 29, which will be described later. Gearbox 32 has a through-hole 32a through which connector 24 is exposed. As described later, connector 24 exposed through through-hole 32a is configured to connect to the drive shaft of image forming apparatus 100.

[0077] The developing roller 22 is rotatable about a developing roller rotation axis 22A extending in the first direction. For example... Figure 2 As shown, the developing roller 22 is located at the opening 214 of the housing 21. That is, the developing roller 22 is located at one end portion of the housing 21 in the second direction.

[0078] The developing roller 22 includes a developing roller body 221 and a developing roller shaft 222. The developing roller body 221 is a hollow cylindrical member extending in a first direction. The developing roller body 221 is made of an elastic material such as rubber. The developing roller shaft 222 extends through the developing roller body 221 and is a solid cylindrical member extending along the developing roller rotation axis 22A. The developing roller shaft 222 is made of metal or conductive resin.

[0079] The developing roller body 221 is fixed to the developing roller shaft 222 so as not to rotate relative to the developing roller shaft 222. The developing roller shaft 222 has one end portion in a first direction; this end portion is located on one side in the first direction. The one end portion of the developing roller shaft 222 in the first direction is fixed to the developing roller gear 223 so as not to rotate relative to the developing roller gear 223. With this structure, when the developing roller gear 223 rotates, the developing roller shaft 222 also rotates, and the developing roller body 221 can rotate together with the developing roller shaft 222. Figure 1 As shown, with the developing cartridge 2 attached to the drum unit 1, the outer peripheral surface of the developing roller 221 is in contact with the outer peripheral surface of the photosensitive drum 11.

[0080] Figure 5 The supply roller 23 shown is rotatable about a supply roller rotation axis 23A extending in a first direction. Within the housing 21, the supply roller 23 is positioned further than the developing roller 22 in a direction from one side to the other in a third direction. The supply roller 23 is positioned in a second direction between the first agitator rotation axis 25A of the first agitator 25 and the developing roller rotation axis 22A of the developing roller 22. The supply roller 23 includes a supply roller body 231 and a supply roller shaft 232. The supply roller body 231 is made of an elastic material such as rubber. The supply roller shaft 232 is a solid cylindrical member extending along the supply roller rotation axis 23A. The supply roller shaft 232 extends through the supply roller body 231. The supply roller shaft 232 is made of metal or conductive resin.

[0081] The supply roller body 231 is fixed to the supply roller shaft 232 so as not to rotate relative to the supply roller shaft 232. The supply roller shaft 232 has one end portion in a first direction; this one end portion is located on one side in the first direction. The one end portion of the supply roller shaft 232 in the first direction is fixed to the supply roller gear 233 so as not to rotate relative to the supply roller gear 233. With this structure, when the supply roller gear 233 rotates, the supply roller shaft 232 also rotates, and the supply roller body 231 can rotate together with the supply roller shaft 232.

[0082] like Figure 5As shown, the outer peripheral surface of the supply roller body 231 of the supply roller 23 is in contact with the outer peripheral surface of the developing roller body 221 of the developing roller 22. When the developing roller 22 and the supply roller 23 rotate, the toner in the housing 21 is supplied to the outer peripheral surface of the developing roller 22 through the supply roller 23. At this time, the toner undergoes triboelectric charging between the supply roller 23 and the developing roller 22. In addition, a bias voltage is applied to the developing roller shaft 222 and the supply roller shaft 232. Therefore, by the electrostatic force acting between the toner and the outer peripheral surfaces of the supply roller body 231 and the developing roller 221, the toner is attracted and carried on the outer peripheral surfaces of the supply roller body 231 and the developing roller 221.

[0083] Figure 5 The first stirrer 25 shown is configured to stir a toner contained in a housing 21. The first stirrer 25 is rotatable about a first stirrer rotation axis 25A extending in a first direction. The first stirrer 25 includes a first stirrer shaft 251 and first stirrer fins 253. The first stirrer shaft 251 extends along the first stirrer rotation axis 25A. The first stirrer shaft 251 has an end portion in the first direction; this end portion is located on one side in the first direction. The end portion of the first stirrer shaft 251 in the first direction is fixed to a first stirrer gear 254 so as not to rotate relative to the first stirrer gear 254. The first stirrer gear 254 is positioned outside a first outer surface 211 of the housing 21.

[0084] like Figure 5 As shown, the first agitator shaft 251 includes a fin support portion 252, which is generally plate-shaped. The fin support portion 252 is positioned within the housing 21 and extends in a first direction. First agitator fins 253 are fixed to the fin support portion 252. The first agitator fins 253 extend in the first direction and also extend radially outward relative to the first agitator rotation axis 25A. The first agitator fins 253 are, for example, flexible membranes.

[0085] The tip of the first agitator fin 253 contacts the inner surface of the housing 21. When the first agitator gear 254 rotates clockwise when viewed from one side in the first direction, the first agitator shaft 251 also rotates, and the first agitator fin 253 also rotates together with the fin support portion 252 about the first agitator rotation axis 25A. During the rotation of the first agitator fin 253, the tip of the first agitator fin 253 bends and deforms by contacting the inner surface of the housing 21.

[0086] The second stirrer 26 is configured to stir the toner contained in the housing 21. The second stirrer 26 is rotatable about a second stirrer rotation axis 26A extending in the first direction. Figure 5 As shown, the second agitator 26 is located between the supply roller 23 and the first agitator 25 in the second direction. Figure 10 As shown, the second stirrer 26 includes a second stirrer shaft 261. The second stirrer shaft 261 is a columnar member extending along the rotation axis 26A of the second stirrer.

[0087] like Figure 5 As shown, the second stirrer shaft 261 includes a stirring portion 262 having a polygonal cylindrical shape. In other words, the second stirrer 26 has a polygonal cylindrical shape rotatable about the second stirrer rotation axis 26A. The stirring portion 262 is located in the housing 21 and extends in a first direction. In this embodiment, the stirring portion 262 has a triangular prism shape, with its three corner portions (i.e., three ridge portions) each serving as a second stirrer fin 263.

[0088] The second stirrer shaft 261 has one end portion in a first direction; this end portion is located on one side in the first direction. The one end portion of the second stirrer shaft 261 in the first direction is fixed to the second stirrer gear 264 so as not to rotate relative to the second stirrer gear 264. When the second stirrer gear 264 rotates, the second stirrer shaft 261 also rotates, and the second stirrer fins 263 also rotate together with the stirring portion 262 about the second stirrer rotation axis 26A.

[0089] Figure 6 This is an exploded stereoscopic view of a portion of developing cartridge 2. (Example) Figure 6 As shown, the developing cartridge 2 also includes a connector 24, a freewheeling gear 27, a first drive gear 28, a second drive gear 29, and a support member 31. Figure 7 The developing cartridge 2 is shown when viewed from one side in the first direction and in the state where the gearbox 32 has been removed. Figure 8 It shows from Figure 7 Remove the state of connector 24, developing roller gear 223 and supply roller gear 233. Figure 9 It shows from Figure 8 Remove the state of the idling gear 27 and the first agitator gear 254. Figure 10 It shows from Figure 9 The state of removing support member 31.

[0090] like Figure 7 , Figure 8 and Figure 10 As shown, the first drive gear 28, the second drive gear 29, the first stirrer gear 254, and the second stirrer gear 264 are directly positioned at the first outer surface 211. On the other hand, as... Figure 7 As shown, the developing roller gear 223, the supply roller gear 233, and the connector 24 are attached to the first outer surface 211 via the support member 31.

[0091] The idler gear 27 includes a first idler gear portion 27a, a second idler gear portion 27b, and a third idler gear portion 27c. For example... Figure 8 As shown, the first idler gear portion 27a and the third idler gear portion 27c are positioned further than the support member 31 in the direction from one side to the other side of the first direction. Figure 9 As shown, the second idler gear portion 27b is positioned further than the support member 31 in the direction from one side to the other in the first direction.

[0092] exist Figures 6 to 11 In this diagram, the developing roller gear 223, the supply roller gear 233, the first agitator gear 254, the second agitator gear 264, the connector 24, the idler gear 27, the first drive gear 28, and the second drive gear 29 are not depicted. Although these gears transmit rotational force through their meshing engagement, they can be replaced with gears that transmit rotational force through friction. For example, these gears could have an outer circumferential surface made of rubber instead of gear teeth.

[0093] Figure 6 and 7 The connector 24 shown is a gear that first receives driving force supplied from the drive shaft of the image forming apparatus 100. The connector 24 is positioned in a first direction at a first outer surface 211 of the housing 21. The connector 24 is rotatable about a connector axis 241 extending in the first direction. The connector 24 includes a connector gear portion that meshes with a freewheeling gear 27. The connector 24 also meshes with both the developing roller gear 223 and the supply roller gear 233. With this configuration, when the connector 24 rotates about the connector axis 241 in response to the driving force from the drive shaft, the freewheeling gear 27, the developing roller gear 223, and the supply roller gear 233 meshing with the connector 24 also rotate. The connector 24 is rotatably supported by a support member 31.

[0094] Figures 6 to 8 The idler gear 27 shown is configured to transmit the rotation of the coupling 24 to the first agitator gear 254. The idler gear 27 is rotatable about an idler axis 271 extending in a first direction. The idler gear 27 includes a first idler gear portion 27a and a second idler gear portion 27b arranged in the first direction (see...). Figure 9 and 10 ) and the third idler gear section 27c.

[0095] The first idler gear portion 27a, the second idler gear portion 27b, and the third idler gear portion 27c have different diameters. The second idler gear portion 27b is positioned closer to the first outer surface 211 of the housing 21 in a first direction than both the first idler gear portion 27a and the third idler gear portion 27c. Specifically, the second idler gear portion 27b is received in a recess 211a of the first outer surface 211 of the housing 21. The third idler gear portion 27c is located between the first idler gear portion 27a and the second idler gear portion 27b in a first direction. The third idler gear portion 27c engages with the first agitator gear 254. The first idler gear portion 27a engages with the connector gear portion of the connector 24. The second idler gear portion 27b engages with the first drive gear 28.

[0096] Figure 10 The first drive gear 28 and the second drive gear 29 shown are configured to transmit the rotation of the idler gear 27 to the second agitator gear 264. The first drive gear 28 is rotatable about a first drive axis 281 extending in a first direction. The first drive gear 28 meshes with a second idler gear portion 27b of the idler gear 27. The first drive gear 28 is housed in a recessed portion 211a of the first outer surface 211 of the housing 21. The second drive gear 29 is rotatable about a second drive axis 291 extending in the first direction. The second drive gear 29 meshes with the first drive gear 28. The second drive gear 29 is housed in a recessed portion 211a of the first outer surface 211 of the housing 21.

[0097] Figure 8 and 9 The support member 31 shown rotatably supports the connector 24. The support member 31 has an approximately flat plate shape extending in both the second and third directions. Figure 6 As shown, the support member 31 includes a hollow cylindrical portion 31a. The support member 31 has a side portion and a side portion opposite to each other in a first direction; the side portion is located on one side of the first direction, and the side portion is located on the other side of the first direction. The hollow cylindrical portion 31a protrudes from a flat surface located at one side portion of the support member 31 in the first direction. The hollow cylindrical portion 31a is inserted into the connector 24. Using this structure, the connector 24 is rotatably supported by one side portion of the support member 31 in the first direction.

[0098] The support member 31 divides the internal space of the gearbox 32 into a side space and a side space in a first direction; the side space is located on one side of the first direction, and the side space is located on the other side of the first direction. Specifically, the connector 24, the developing roller gear 223, and the supply roller gear 233 are positioned in the side space of the support member 31 in the first direction. The support member 31 has a circular hole for allowing the developing roller shaft 222 and the supply roller shaft 232 to extend through the support member 31. On the other hand, the first drive gear 28, the second drive gear 29, and the second stirrer gear 264 are positioned in the other side space of the support member 31 in the first direction. Specifically, with the first drive gear 28, the second drive gear 29, and the second stirrer gear 264 accommodated in a recessed portion 211a of the first outer surface 211 of the housing 21, the recessed portion 211a is partially covered by the support member 31 from one side of the first direction. The recessed portion 211a is recessed in the direction from one side to the other in the first direction. The second idler gear portion 27b of the idler gear 27 is also accommodated in the recessed portion 211a.

[0099] Figure 11 It shows from Figure 10 The states of the first drive gear 28, the second drive gear 29, and the second stirrer gear 264 are removed. For example... Figure 6 and 11 As shown, the support shaft for rotatably supporting the idler gear 27, the first drive gear 28, and the second drive gear 29 protrudes from the bottom surface of the recessed portion 211a in a direction from one side to the other in the first direction. Furthermore, the bottom portion of the recessed portion 211a has a through-hole for filling the internal space of the housing 21 with toner. A sealing member 266 is accommodated in the through-hole. The sealing member 266 has a side portion in the first direction; this side portion is located on one side in the first direction. A second stirrer gear 264 is disposed at the side portion of the sealing member 266 in the first direction. With this structure, since the second stirrer gear 264 is positioned at the through-hole via the sealing member 266, leakage of toner from the housing 21 is prevented.

[0100] In the image forming apparatus 100 constructed as described above, when the connector 24 rotates about the connector axis 241 in response to a driving force from the drive shaft, the developing roller gear 223, the supply roller gear 233, and the idler gear 27, which mesh with the connector 24, also rotate. Due to the rotation of the idler gear 27, the first agitator gear 254, which meshes with the idler gear 27, also rotates. Furthermore, due to the rotation of the idler gear 27, the first drive gear 28, which meshes with the idler gear 27, rotates. When the first drive gear 28 rotates, the second drive gear 29, which meshes with the first drive gear 28, rotates. According to the rotation of the second drive gear 29, the second agitator gear 264, which meshes with the second drive gear 29, also rotates.

[0101] With the gears engaged as described above, the second agitator gear 264 rotates at a frequency greater than that of the first agitator gear 254, depending on the number of teeth on the gears. In this embodiment, the rotational frequency of the second agitator gear 264 is approximately three to four times that of the first agitator gear 254. However, the number of teeth and the diameter of the gears are set such that the circumferential speed of the second agitator 26 is greater than or equal to the circumferential speed of the supply roller 23.

[0102] Note that no gear is provided between the idler gear 27 and the first agitator gear 254. On the other hand, an even number of gears (in this embodiment, the first drive gear 28 and the second drive gear 29) are provided between the idler gear 27 and the second agitator gear 264. Therefore, the first agitator gear 254 and the second agitator gear 264 rotate in the same direction of rotation (in this embodiment, clockwise when viewed from one side of the first direction).

[0103] In the printing process of the image forming apparatus 100, the outer peripheral surface of the photosensitive drum 11 is uniformly charged and then exposed by a laser beam or an LED beam, thereby forming an electrostatic latent image based on input image data on the outer peripheral surface of the photosensitive drum 11. Furthermore, while the toner in the housing 21 is stirred by a rotating first agitator 25 and a rotating second agitator 26, the toner is supplied to the outer peripheral surface of the supply roller 23, and then from the outer peripheral surface of the supply roller 23 to the outer peripheral surface of the developing roller 22. Subsequently, by the rotation of the developing roller 22, a thin layer of toner is formed on the outer peripheral surface of the developing roller body 221.

[0104] Toner carried on the outer peripheral surface of the developing roller 22 is supplied to an electrostatic latent image formed on the outer peripheral surface of the photosensitive drum 11. Thus, the electrostatic latent image becomes a visible toner image on the outer peripheral surface of the photosensitive drum 11. The toner image is transferred onto the recording surface of the printed sheet, and then the toner image is thermally fixed, thereby terminating the printing process.

[0105] As described above, the developing cartridge 2 according to the embodiment includes a housing 21, a developing roller 22, a first agitator 25, a supply roller 23, and a second agitator 26. Here, the rotation path of the second agitator fins 263 of the second agitator 26 is located outside the rotation path of the first agitator fins 253 of the first agitator 25. Therefore, within the internal space of the housing 21, the toner located in areas where sufficient toner mixing cannot be achieved by the rotation of the first agitator 25 alone can be mixed by the rotation of the second agitator 26. Thus, even if the remaining amount of toner in the internal space of the housing 21 becomes low, sufficient toner mixing can still be achieved.

[0106] Furthermore, in the developing cartridge 2 according to the embodiment, the second agitator 26 is closer to the supply roller 23 in the second direction than the first agitator 25 is. Therefore, the toner retained around the supply roller 23 can be agitated by the rotation of the second agitator 26. Thus, the retention of toner flow around the supply roller 23 in the internal space of the housing 21 can be suppressed.

[0107] Furthermore, in the developing cartridge 2 according to the embodiment, the first stirrer 25 and the second stirrer 26 rotate in the same direction of rotation. Therefore, the toner stream formed by the rotation of the second stirrer 26 can be easily merged into the toner stream formed by the rotation of the first stirrer 25. As a result, the toner retained in the housing 21 can be introduced into the stirring area of ​​the first stirrer 25, thereby ensuring thorough overall stirring of the toner.

[0108] Furthermore, the developing cartridge 2 according to this embodiment includes a connector 24, a developing roller gear 223, a supply roller gear 233, a first agitator gear 254, a second agitator gear 264, an idler gear 27, a first drive gear 28, and a second drive gear 29. Thus, the developing cartridge 2 includes an even number of drive gears, namely the first drive gear 28 and the second drive gear 29. Therefore, the first agitator 25 and the second agitator 26 can rotate at a constant speed ratio. Furthermore, when viewed in the first direction, the first agitator 25 and the second agitator 26 rotate in the same direction of rotation. Therefore, the toner flow formed by the agitation of the second agitator 26 can easily merge with the toner flow formed by the agitation of the first agitator 25. On the other hand, in the region between the outer peripheral surface of the second agitator 26 and the outer peripheral surface of the supply roller 23, when viewed in the first direction, the rotation directions of the second agitator 26 and the supply roller 23 are the same. As a result, the rotation of the second agitator 26 can easily supply toner to the outer peripheral surface of the supply roller 23.

[0109] Furthermore, in the developing cartridge 2 according to the embodiment, the developing roller gear 223 and the supply roller gear 233 are located on one side of the support member 31 in the first direction, while the first drive gear 28, the second drive gear 29, and the second stirrer gear 264 are located on the other side of the support member 31 in the first direction. With this structure, the developing roller gear 223, the supply roller gear 233, the first drive gear 28, the second drive gear 29, and the second stirrer gear 264 can be divided into one side and one side in the first direction of the support member 31, and each is located on a corresponding side of the two side portions. As a result, a high gear layout density can be achieved within a limited space, making the developing cartridge 2 compact.

[0110] Furthermore, in the developing cartridge 2 according to this embodiment, the first outer surface 211 of the housing 21 has a recessed portion 211a that is recessed in the direction from one side to the other in a first direction. The first drive gear 28, the second drive gear 29, and the second stirrer gear 264 are accommodated in the recessed portion 211a. With this structure, the first drive gear 28, the second drive gear 29, and the second stirrer gear 264 can be additionally accommodated in the gearbox 32 with almost no change to the conventional gear layout, such as the layout of the connector 24, the developing roller gear 223, and the supply roller gear 233. Therefore, the second stirrer 26 can be easily used in the developing cartridge 2.

[0111] Furthermore, in the developing cartridge 2 according to the embodiment, the rotation frequency of the second stirrer 26 is greater than that of the first stirrer 25. Additionally, the diameter of the second stirrer fins 263 about the second stirrer rotation axis 26A is smaller than the diameter of the first stirrer fins 253 about the first stirrer rotation axis 25A. Therefore, by rotating the second stirrer 26, which is smaller than the first stirrer 25 and rotates at a higher speed, the toner retained in the internal space of the housing 21 can be easily introduced into a wider stirring area of ​​the first stirrer 25.

[0112] Furthermore, in the developing cartridge 2 according to this embodiment, the circumferential speed of the second agitator 26 (i.e., the moving speed of the second agitator fins 263) is greater than or equal to the circumferential speed of the supply roller 23 (i.e., the moving speed of the outer peripheral surface of the supply roller body 231). Therefore, insufficient supply of toner to the supply roller 23 can be prevented.

[0113] Furthermore, in the developing cartridge 2 according to the embodiment, the first agitator fin 253 and the second agitator fin 263 do not contact each other. This structure prevents complex toner flow within the housing 21 due to interference between the first agitator fin 253 and the second agitator fin 263, thereby promoting uniform mixing of the toner.

[0114] Furthermore, in the developing cartridge 2 according to this embodiment, the first agitator fin 253 is a sheet-like film. Therefore, by rotating the first agitator 25, the tip portion of the first agitator fin 253 can be bent while contacting the inner surface of the housing 21. Thus, the toner adhering to the inner surface of the housing 21 can be scraped off. As a result, the toner in the housing 21 can be further mixed more evenly. In other words, toner retention can be suppressed throughout the entire internal space of the housing 21.

[0115] Furthermore, in the developing cartridge 2 according to the embodiment, the second stirrer 26 has a polygonal column shape, with each of its corner portions serving as a second stirrer fin 263. Therefore, a second stirrer fin 263 with high rigidity can be achieved.

[0116] <4. Modified Example>

[0117] Although detailed descriptions have been made with reference to specific embodiments, it will be apparent to those skilled in the art that many modifications and variations can be made thereto. Various modifications to the above embodiments will now be briefly described.

[0118] Although in the above embodiment the second stirrer 26 has a triangular prism shape that can rotate about the second stirrer rotation axis 26A, the shape of the second stirrer 26 is not limited to a triangular prism shape. For example, the second stirrer 26 may have a pentagonal prism shape or a hexagonal prism shape instead of a triangular prism shape.

[0119] Furthermore, the shape of the second stirrer 26 is not limited to any polygonal prism shape. For example, the second stirrer fins 263 of the second stirrer 26 may include: a rotating member rotatable about the rotation axis 26A of the second stirrer; and a plurality of fin portions, each extending radially outward from the rotating member. The fin portions may have a flat or curved shape. With this modification, the surface area of ​​the second stirrer fins 263 can be increased. As a result, the toner retained in the internal space of the housing 21 can be thoroughly stirred by the second stirrer fins 263.

[0120] In the above embodiment, the first agitator fin 253 is a sheet-like membrane. However, a plastic sheet can also be used as the first agitator fin 253.

[0121] The developing roller gear 223, the supply roller gear 233, the first agitator gear 254, the second agitator gear 264, the connector 24, the idler gear 27, the first drive gear 28 and the second drive gear 29 can be positioned at the second outer surface 212, which is the outer surface of the housing 21 on the other side in the first direction.

[0122] Furthermore, the detailed configuration of the developing cartridge can be modified appropriately. Additionally, various features appearing in the above embodiments and their modifications can be appropriately combined, provided no contradictions arise.

[0123] Reference Symbol List

[0124] 1: Drum Unit

[0125] 2: Developing box

[0126] 11: Photosensitive drum

[0127] 12: Framework

[0128] 21: Shell

[0129] 22: Developing roller

[0130] 23: Supply Roller

[0131] 24: Connector

[0132] 25: First mixer

[0133] 26: Second mixer

[0134] 27: Idle gear

[0135] 27b: Second idler gear section

[0136] 28: First drive gear

[0137] 29: Second drive gear

[0138] 31: Supporting Components

[0139] 32: Gearbox

[0140] 32a: Through hole

[0141] 100: Image forming apparatus

[0142] 101: Main body shell

[0143] 102: Controller

[0144] 120: Box holding section

[0145] 211: First outer surface

[0146] 211a: Depressed portion

[0147] 212: Second outer surface

[0148] 214: Opening

[0149] 221: Developing roller body

[0150] 222: Developing roller shaft

[0151] 223: Developing roller gear

[0152] 231: Supply roller body

[0153] 232: Supply rollers

[0154] 233: Supply of roller gears

[0155] 241: Connector axis

[0156] 251: First stirrer shaft

[0157] 252: Fin support section

[0158] 253: First agitator fins

[0159] 254: First agitator gear

[0160] 261: Second stirrer shaft

[0161] 262: Stirring section

[0162] 263: Second agitator fins

[0163] 264: Second agitator gear

[0164] 266: Sealing component

Claims

1. A developing cartridge, characterized in that, include: A housing configured to contain a toner, the housing having an end portion in a first direction, the end portion having an outer surface; A developing roller, which is rotatable about a developing roller rotation axis extending in the first direction; A first stirrer, configured to stir the toner, is rotatable about a first stirrer rotation axis extending in the first direction. A second stirrer, the second stirrer being rotatable about a second stirrer rotation axis extending in the first direction; A connector located on the outer surface, the connector being rotatable about a connector axis extending in the first direction, the connector including a connector gear portion; A first agitator gear is located on the outer surface and is capable of rotating together with the first agitator. A second agitator gear is located on the outer surface and is rotatable with the second agitator. The second agitator gear is positioned closer to the outer surface in the first direction than the connector is to the outer surface. At least a portion of the second agitator gear is located between the connector and the outer surface in the first direction. and A freewheeling gear, rotatable in response to the rotation of the coupling, the freewheeling gear comprising: The first idler gear portion meshes with the coupling gear portion; The second idler gear portion is positioned closer to the outer surface in the first direction than the first idler gear portion is closer to the outer surface. A first drive gear, which partially meshes with a second idler gear; and The second drive gear meshes with both the first drive gear and the second agitator gear.

2. The developing cartridge according to claim 1, characterized in that, Further includes: A support member, which is flat in shape, has a side portion and a side portion opposite to each other in the first direction, wherein the side portion is positioned further away from the outer surface than the side portion is positioned further away from the outer surface. The connector is located at one side portion of the support member, and The second agitator gear is located on the other side of the support member.

3. The developing cartridge according to claim 2, characterized in that, in, The first drive gear and the second drive gear are located on the other side portion of the support member.

4. The developing cartridge according to claim 3, characterized in that, The outer surface has a recessed portion that is recessed in the first direction from one end portion of the housing to the other end portion. The first drive gear, the second drive gear, and the second stirrer gear are housed in the recessed portion.

5. A developing cartridge, characterized in that, include: A housing configured to contain a toner, the housing having an end portion in a first direction, the end portion having an outer surface; A developing roller, which is rotatable about a developing roller rotation axis extending in the first direction; A first stirrer, configured to stir the toner, is rotatable about a first stirrer rotation axis extending in the first direction. A second stirrer, the second stirrer being rotatable about a second stirrer rotation axis extending in the first direction; A connector located on the outer surface, the connector being rotatable about a connector axis extending in the first direction, the connector including a connector gear portion; A first agitator gear is located on the outer surface and is capable of rotating together with the first agitator. A second agitator gear is located on the outer surface and is rotatable with the second agitator. The second agitator gear is positioned closer to the outer surface in the first direction than the connector is to the outer surface. At least a portion of the second agitator gear is located between the connector and the outer surface in the first direction. And a freewheeling gear, the freewheeling gear being rotatable in response to the rotation of the coupling, the freewheeling gear comprising: The first idler gear portion meshes with the coupling gear portion; The second idler gear portion is positioned closer to the outer surface in the first direction than the first idler gear portion is closer to the outer surface; and An even number of drive gears, the even number of drive gears being configured to transmit driving force from the second idler gear portion to the second agitator gear.

6. The developing cartridge according to claim 5, characterized in that, Further includes: A support member, which is flat in shape, has a side portion and a side portion opposite to each other in the first direction, wherein the side portion is positioned further away from the outer surface than the side portion is positioned further away from the outer surface. The connector is located at one side portion of the support member, and The second agitator gear is located on the other side of the support member.

7. The developing cartridge according to claim 6, characterized in that, in, The drive gear is located on the other side portion of the support member.

8. The developing cartridge according to claim 7, characterized in that, The outer surface has a recessed portion that is recessed in the first direction from one end portion of the housing to the other end portion. The drive gear and the second agitator gear are housed in the recessed portion.

9. A developing cartridge, characterized in that, include: A housing configured to contain a toner, the housing having an end portion in a first direction, the end portion having an outer surface; A developing roller, which is rotatable about a developing roller rotation axis extending in the first direction; A first stirrer, configured to stir the toner, is rotatable about a first stirrer rotation axis extending in the first direction. A second stirrer, the second stirrer being rotatable about a second stirrer rotation axis extending in the first direction; A connector located on the outer surface, the connector being rotatable about a connector axis extending in the first direction, the connector including a connector gear portion; A first agitator gear is located on the outer surface and is capable of rotating together with the first agitator. A second agitator gear is located on the outer surface and is rotatable with the second agitator. The second agitator gear is positioned closer to the outer surface in the first direction than the connector is to the outer surface. At least a portion of the second agitator gear is located between the connector and the outer surface in the first direction. and A support member, which is flat in shape, has a side portion and a side portion opposite to each other in the first direction, wherein the side portion is positioned further away from the outer surface than the side portion is positioned further away from the outer surface. The connector is located at one side portion of the support member, and The second agitator gear is located on the other side of the support member.

10. The developing cartridge according to any one of claims 1 to 9, characterized in that, Further includes: A developing roller gear, located on the outer surface, is capable of rotating together with the developing roller according to the rotation of the connector.

11. The developing cartridge according to claim 10, characterized in that, The developing roller includes a developing roller shaft extending in the first direction, and The developing roller gear is attached to the developing roller shaft and is capable of rotating together with the developing roller shaft.

12. The developing cartridge according to any one of claims 1 to 9, characterized in that, Further includes: A supply roller is located between the first agitator and the developing roller, and the supply roller is rotatable about a supply roller rotation axis extending in the first direction.

13. The developing cartridge according to claim 12, characterized in that, Further includes: A supply roller gear is located on the outer surface and is capable of rotating together with the supply roller according to the rotation of the connector.

14. The developing cartridge according to claim 13, characterized in that, The supply roller includes a supply roller shaft extending in the first direction, and The supply roller gear is attached to the supply roller shaft and is capable of rotating together with the supply roller shaft.

15. The developing cartridge according to claim 12, characterized in that, The circumferential speed of the second agitator is greater than or equal to the circumferential speed of the supply roller.

16. The developing cartridge according to claim 12, characterized in that, The supply roller is configured to supply the toner to the outer peripheral surface of the developing roller.

17. The developing cartridge according to claim 12, characterized in that, The outer peripheral surface of the developing roller is in contact with the outer peripheral surface of the supply roller.

18. The developing cartridge according to claim 12, characterized in that, The supply roller is located between the first stirrer and the developing roller in a second direction connecting the rotation axis of the first stirrer and the rotation axis of the developing roller.

19. The developing cartridge according to claim 18, characterized in that, The second agitator is located between the supply roller and the first agitator in the second direction.

20. The developing cartridge according to claim 19, characterized in that, The second agitator is positioned closer to the supply roller in the second direction than the first agitator is.

21. The developing cartridge according to any one of claims 1 to 9, characterized in that, The second stirrer rotates in the same direction as the first stirrer.

22. The developing cartridge according to any one of claims 1 to 9, characterized in that, The connector is capable of rotating about its axis in response to receiving a driving force.

23. The developing cartridge according to any one of claims 1 to 9, characterized in that, The first stirrer includes a first stirrer shaft extending in the first direction, and The first agitator gear is attached to the first agitator shaft and is capable of rotating together with the first agitator shaft.

24. The developing cartridge according to any one of claims 1 to 9, characterized in that, The second stirrer includes a second stirrer shaft extending in the first direction, and The second agitator gear is attached to the second agitator shaft and is capable of rotating together with the second agitator shaft.

25. The developing cartridge according to any one of claims 1 to 9, characterized in that, The rotational frequency of the second stirrer is greater than that of the first stirrer.

26. The developing cartridge according to any one of claims 1 to 9, characterized in that, The first agitator includes first agitator fins capable of rotating about the first agitator rotation axis. The second agitator includes second agitator fins capable of rotating about the axis of rotation of the second agitator, and The first agitator fins and the second agitator fins do not contact each other.

27. The developing cartridge according to claim 26, characterized in that, The first agitator fin is a sheet-like membrane.

28. The developing cartridge according to claim 26, characterized in that, The second stirrer has a polygonal columnar shape, and the corner portions of the polygonal columnar shape are each used as fins of the second stirrer.

29. The developing cartridge according to claim 26, characterized in that, in, The second agitator fins include: A rotating body, the rotating body being rotatable about the rotation axis of the second stirrer; and Multiple fin portions, each of which extends radially outward from the outer peripheral surface of the rotating body.

30. The developing cartridge according to claim 26, characterized in that, The diameter of the second agitator fin relative to the rotation axis of the second agitator is smaller than the diameter of the first agitator fin relative to the rotation axis of the first agitator.

Images