JP2022075877A - Developing cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing cartridge that can satisfactorily stir toner.

SOLUTION: A housing 21 stores a toner. A developing roller 22 is rotatable about a developing roller rotary shaft extending in a first direction. A first agitator 25 can stir the toner and is rotatable about a first agitator rotary shaft extending in the first direction. A supply roller 23 is located between the first agitator 25 and developing roller 22, is rotatable about a supply roller rotary shaft extending in the first direction, and can supply the toner to an outer peripheral surface of the developing roller 22. A second agitator 26 is located between the supply roller 23 and first agitator 25 and rotatable about a second agitator rotary shaft extending in the first direction. In the developing cartridge 2, the rotation locus of the second agitator 26 is located outside the rotation locus of the first agitator 25.

SELECTED DRAWING: Figure 5

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present disclosure relates to a developing cartridge.

Conventionally, an electrophotographic image forming apparatus such as an LED printer is known. This type of image forming apparatus has a frame having a photoconductor drum and a developing cartridge that can be attached to and detached from the frame. A conventional image forming apparatus having a developing cartridge is described in, for example, Patent Document 1.

The developing cartridge described in Patent Document 1 includes a housing, a developing roller, an agitator, and a supply roller. The housing can accommodate toner. The developing roller is rotatable about a rotation axis extending in the first direction. The agitator agitates the toner in the housing by rotating about a rotation axis extending in the first direction. The agitator is spaced apart from the developing rollers in the second direction. The supply roller supplies toner to the developing roller by rotating about a rotation axis extending in the first direction. The supply roller is located between the developing roller and the agitator in the second direction.

Japanese Unexamined Patent Publication No. 2018-66973

However, in the cartridge described in Patent Document 1, there is a region in the internal space of the housing where the toner cannot be agitated only by the rotation of the agitator. For example, when the remaining amount of toner in the housing is low, toner may stay in the area around the supply roller.

It is an object of the present disclosure to provide a developing cartridge that enables good stirring of toner in the internal space of a housing.

In the first aspect of the present application, a developing cartridge including a housing, a developing roller, a first agitator, a supply roller, and a second agitator is provided. The housing can accommodate toner. The developing roller is rotatable about a developing roller rotation axis extending in the first direction. The first agitator is a first agitator capable of stirring the toner, and is rotatable about a rotation shaft of the first agitator extending in the first direction. The supply roller is a supply roller located between the first agitator and the developing roller, and is a supply roller rotatable about the supply roller rotating shaft extending in the first direction on the outer peripheral surface of the developing roller. The toner can be supplied. The second agitator is a second agitator located between the supply roller and the first agitator, and is rotatable about a second agitator rotation axis extending in the first direction. In this developing cartridge, the rotation locus of the second agitator is located outside the rotation locus of the first agitator.

In the second aspect of the present application, in the developing cartridge of the first aspect, the outer peripheral surface of the supply roller comes into contact with the outer peripheral surface of the developing roller.

From the third aspect of the present application, in the developing cartridge according to the first aspect or the second aspect, the supply roller is the said in the second direction connecting the first agitator rotating shaft and the developing roller rotating shaft. It is located between the first agitator and the developing roller.

In the fourth aspect of the present application, in the developing cartridge according to the third aspect, the second agitator is located between the supply roller and the first agitator in the second direction.

From the fifth aspect of the present application, in the developing cartridge according to the fourth aspect, the second agitator is closer to the supply roller than the first agitator in the second direction.

In the sixth aspect of the present application, in any one of the developing cartridges from the first aspect to the fifth aspect, the first agitator and the second agitator rotate in the same direction.

From the seventh aspect of the present application, in any one of the developing cartridges from the first aspect to the sixth aspect, the coupling, the developing roller gear, the supply roller gear, the first agitator gear, and the second agitator gear , An idle gear, a first drive gear, and a second drive gear. The coupling is a coupling that is located on the outer surface of one side of the housing in the first direction and is rotatable about a coupling shaft extending in the first direction, and has a coupling gear portion. The developing roller gear is a developing roller gear that can rotate together with the developing roller according to the rotation of the coupling, and is located on the outer surface of the housing. The supply roller gear is a supply roller gear that can rotate with the supply roller according to the rotation of the coupling, and is located on the outer surface of the housing. The first agitator gear is a first agitator gear that can rotate together with the first agitator and is located on the outer surface of the housing. The second agitator gear is a second agitator gear that can rotate together with the second agitator, and is a second agitator gear located on the outer surface of the housing, in the first direction, more than the coupling. A second agitator gear located near the outer surface of the housing, wherein at least a portion of the second agitator gear in the first direction comprises the coupling and the outer surface of the housing. Located in between. The idle gear can rotate according to the rotation of the coupling. The idle gear includes a first idle gear portion and a second idle gear portion. The first idle gear portion meshes with the coupling gear portion. The second idle gear portion is located closer to the outer surface of the housing than the first idle gear portion in the first direction. The first drive gear meshes with the second idle gear portion. The second drive gear is a second drive gear that meshes with the first drive gear, and meshes with the second agitator gear.

From the eighth aspect of the present application, in any one of the developing cartridges from the first aspect to the sixth aspect, the coupling, the developing roller gear, the supply roller gear, the first agitator gear, and the second agitator gear , An idle gear and an even number of drive gears. The coupling is a coupling that is located on the outer surface of one side of the housing in the first direction and is rotatable about a coupling shaft extending in the first direction, and has a coupling gear portion. The developing roller gear is a developing roller gear that can rotate together with the developing roller according to the rotation of the coupling, and is located on the outer surface of the housing. The supply roller gear is a supply roller gear that can rotate with the supply roller as the coupling rotates, and is located on the outer surface of the housing. The first agitator gear is a first agitator gear that can rotate together with the first agitator and is located on the outer surface of the housing. The second agitator gear is a second agitator gear that can rotate together with the second agitator, and is a second agitator gear located on the outer surface of the housing, in the first direction, more than the coupling. A second agitator gear located near the outer surface of the housing, wherein at least a portion of the second agitator gear in the first direction comprises the coupling and the outer surface of the housing. Located in between. The idle gear can rotate according to the rotation of the coupling. The idle gear includes a first idle gear portion and a second idle gear portion. The first idle gear portion meshes with the coupling gear portion. The second idle gear portion is located closer to the outer surface of the housing than the first idle gear portion in the first direction. The even number of drive gears transmit a driving force from the second idle gear portion to the second agitator gear.

In the ninth aspect of the present application, in the developing cartridge of the seventh aspect or the eighth aspect, the coupling is rotatable about the coupling shaft in response to receiving a driving force.

In the tenth aspect of the present application, in any one of the developing cartridges from the seventh aspect to the ninth aspect, the developing roller includes a developing roller shaft extending in the first direction. The developing roller gear is mounted on the developing roller shaft and can rotate together with the developing roller shaft.

In the eleventh aspect of the present application, in any one of the developing cartridges from the seventh aspect to the tenth aspect, the supply roller includes a supply roller shaft extending in the first direction. The supply roller gear is mounted on the supply roller shaft and is rotatable together with the supply roller shaft.

In the twelfth aspect of the present application, in any one of the developing cartridges from the seventh aspect to the eleventh aspect, the first agitator includes a first agitator shaft extending in the first direction. The first agitator gear is mounted on the first agitator shaft and is rotatable together with the first agitator shaft.

In the thirteenth aspect of the present application, in any one of the developing cartridges from the seventh aspect to the twelfth aspect, the second agitator includes a second agitator shaft extending in the first direction. The first agitator gear is mounted on the second agitator shaft and is rotatable together with the second agitator shaft.

In the fourteenth aspect of the present application, the support member is further provided in any one of the developing cartridges from the seventh aspect to the thirteenth aspect. The support member is a planar support member that extends in the second direction and a third direction that intersects the first direction and the second direction, and the support member is the support member in the first direction. The coupling is rotatably supported on one side. The developing roller gear and the supply roller gear are arranged on one side of the support member in the first direction. The drive gear and the second agitator gear are arranged on the other side of the support member in the first direction.

In the fifteenth aspect of the present application, in any one of the developing cartridges from the seventh aspect to the fourteenth aspect, the outer surface of the housing has a recess recessed on the other side in the first direction. The drive gear and the second agitator gear are housed in the recess.

From the 16th viewpoint of the present application, in any one of the developing cartridges from the 1st viewpoint to the 15th viewpoint, the rotation speed of the second agitator is higher than the rotation speed of the first agitator.

From the 17th aspect of the present application, in any one of the developing cartridges from the 1st aspect to the 16th aspect, the peripheral speed of the second agitator is equal to or faster than the peripheral speed of the supply roller.

In the eighteenth aspect of the present application, in any one of the developing cartridges from the first aspect to the seventeenth aspect, the first agitator has a first agitator blade that rotates about the first agitator rotation axis. The second agitator has a second agitator blade that rotates about the second agitator rotation axis. The first agitator blade and the second agitator blade do not come into contact with each other.

From the 19th aspect of the present application, in the developing cartridge of the 18th aspect, the first agitator blade is a sheet-like film.

From the twentieth aspect of the present application, in the developing cartridge according to the eighteenth aspect or the nineteenth aspect, the second agitator is a polygonal prism that rotates about the second agitator rotation axis. The second agitator blade is a plurality of corners of the polygonal prism.

From the 21st aspect of the present application, in the developing cartridge according to the 18th aspect or the 19th aspect, the second agitator blade projects radially outward from the outer peripheral portion of the rotating body rotating about the second agitator rotation axis. It has a plurality of blades.

From the 22nd viewpoint of the present application, in any one of the developing cartridges from the 18th viewpoint to the 21st viewpoint, the diameter of the second agitator blade about the second agitator rotation axis is the diameter of the first agitator rotation. It is smaller than the diameter of the first agitator blade centered on the shaft.

According to the first aspect to the 22nd aspect of the present application, there is provided a developing cartridge capable of satisfactorily stirring toner in the internal space of the housing.

According to the first aspect of the present application, the region of the internal space of the housing where the toner cannot be agitated only by the rotation of the first agitator can be agitated by rotating the second agitator. .. Therefore, even when the amount of toner remaining in the internal space of the housing is low, the toner can be satisfactorily agitated.

According to the fifth aspect of the present application, the toner staying around the supply roller can be agitated by rotating the second agitator. Therefore, it is possible to suppress the stagnation of the toner flow in the internal space of the housing.

According to the sixth aspect of the present application, the toner flow formed by the rotation of the second agitator is likely to join the toner flow formed by the rotation of the first agitator. As a result, the retained toner can be taken into the stirring region of the first agitator, and the entire toner can be well stirred.

According to the seventh aspect or the eighth aspect of the present application, it is possible to rotate the first agitator and the second agitator at a constant speed ratio. Further, the first agitator and the second agitator rotate in the same direction when viewed in the first direction. Therefore, the flow of the toner formed by being agitated by the second agitator is likely to join the flow of the toner formed by being agitated by the first agitator. From another point of view, in the region where the outer peripheral surface of the second agitator and the outer peripheral surface of the supply roller face each other when viewed in the first direction, the rotation direction of the second agitator and the rotation direction of the supply roller are different. It will be in the same direction. As a result, by rotating the second agitator, it becomes easy to supply the toner to the outer peripheral surface of the supply roller.

According to the fourteenth aspect of the present application, the developing roller gear, the supply roller gear, the drive gear, and the second agitator gear can be arranged on one side and the other side in the first direction of the support member. As a result, many gears can be laid out in a narrow space. Therefore, the size of the developing roller can be reduced.

According to the fifteenth aspect of the present application, the drive gear and the second agitator gear may be additionally housed in the gear case without substantially changing the arrangement of the conventional coupling, the developing roller gear, the supply roller gear, and the like. can. Therefore, it is possible to easily introduce the second agitator having the present configuration into the developing cartridge.

According to the sixteenth aspect of the present application, the toner staying in the internal space of the housing can be easily guided to the stirring region of the first agitator by the rotation of the second agitator.

According to the seventeenth aspect of the present application, it is possible to prevent the amount of toner supplied to the supply roller from becoming insufficient.

According to the eighteenth aspect of the present application, it is possible to prevent a complicated toner flow from occurring in the internal space of the housing due to the interference between the first agitator blade and the second agitator blade. As a result, it becomes easy to uniformly stir the toner.

According to the nineteenth aspect of the present application, by rotating the first agitator, the tip of the first agitator blade acts on the inner surface of the housing to bend it, and the toner adhering to the inner surface of the housing is scraped off. be able to. As a result, it becomes possible to mix the toner more uniformly in the housing.

According to the twentieth aspect of the present application, it is possible to realize a second agitator blade having high rigidity.

According to the 21st aspect of the present application, the surface area of the second agitator blade is increased. As a result, the toner retained in the internal space of the housing can be satisfactorily agitated by the second agitator blade.

It is a schematic diagram of an image forming apparatus. It is a perspective view of the development cartridge. It is a figure when the development cartridge is seen in the 3rd direction. It is a figure when the development cartridge is seen in the 1st direction. It is sectional drawing when the development cartridge is cut in the plane perpendicular to the 1st direction. It is a partially disassembled perspective view of a developing cartridge. It is a figure when the developing cartridge is seen in the 1st direction, and is the figure which shows the state when the gear case is removed. It is a figure which shows the state when the coupling, the developing roller gear, and the supply roller gear are removed from the state of FIG. 7. It is a figure which shows the state when the idle gear and the 1st agitator gear are removed from the state of FIG. It is a figure which shows the state when the support member is removed from the state of FIG. It is a figure which shows the state when the 1st drive gear, the 2nd drive gear, and the 2nd agitator gear are removed from the state of FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

In the following description, the direction in which the development roller rotation axis of the development roller of the development cartridge extends is referred to as the "first direction". Further, when viewed in the first direction, the direction connecting the developing roller rotation axis and the first agitator rotation axis of the first agitator is defined as the "second direction". The first direction and the second direction intersect each other, and more preferably orthogonal to each other. Further, a direction that intersects with and more preferably orthogonal to the first direction and the second direction is referred to as a "third direction".

<1. About image forming equipment>
FIG. 1 is a schematic view of an image forming apparatus 100. The image forming apparatus 100 is an electrophotographic printer. Examples of the image forming apparatus 100 include a laser printer or an LED printer. As shown in FIG. 1, the image forming apparatus 100 includes a main body casing 101, a control unit 102, a drum unit 1, and four developing cartridges 2. The four developing cartridges 2 can be individually attached to the drum unit 1. Further, the drum unit 1 to which the four developing cartridges 2 are mounted is removable from the main body casing 101.

The four developing cartridges 2 contain developing agents (toners in this embodiment) having different colors (for example, cyan, magenta, yellow, and black). The image forming apparatus 100 forms an image on the recording surface of the printing paper by the toner supplied from the four developing cartridges 2. However, the number of developing cartridges 2 mounted on the drum unit 1 may be 1 to 3, or 5 or more.

The control unit 102 shown in FIG. 1 is located inside the main body casing 101. The control unit 102 is composed of, for example, a circuit board. The control unit 102 has a processor such as a CPU and various types of memory. The control unit 102 executes various processes in the image forming apparatus 100 by operating the processor according to the program.

<2. About the drum unit>
The drum unit 1 shown in FIG. 1 includes four photoconductor drums 11 and a frame 12. The photoconductor drum 11 is a member for transferring the toner supplied from the developing cartridge 2 to the printing paper. The four photoconductor drums 11 are arranged at intervals. Each photoconductor drum 11 has a cylindrical outer peripheral surface extending in the first direction. The outer peripheral surface of the photoconductor drum 11 is covered with a photosensitive material. Further, each photoconductor drum 11 is rotatable about a drum rotation axis extending in the first direction.

The frame 12 is a frame body that holds the four photoconductor drums 11. The frame 12 has four developing cartridge holders 120. The four developing cartridge holding units 120 are arranged at intervals. A developing cartridge 2 is attached to each developing cartridge holding portion 120.

<3. About developing cartridges>
FIG. 2 is a perspective view of the developing cartridge 2. FIG. 3 is a view when the developing cartridge 2 is viewed from one side in the third direction. FIG. 4 is a view when the developing cartridge 2 is viewed from one side in the first direction. FIG. 5 is a cross-sectional view of the developing cartridge 2 cut along a plane perpendicular to the first direction. As shown in FIGS. 2 and 3, the developing cartridge 2 includes a housing 21, a developing roller 22, a gear case 32, and a coupling 24. As shown in FIGS. 4 and 5, the developing cartridge 22 further includes a supply roller 23, a first agitator 25, and a second agitator 26.

The housing 21 shown in FIGS. 2 and 3 is a housing capable of accommodating toner. As shown in FIG. 3, the housing 21 extends in the first direction between the first outer surface 211 and the second outer surface 212. Toner is housed inside the housing 21. Further, the housing 21 has an opening 214. The opening 214 is located at one end of the housing 21 in the second direction. The internal space of the housing 21 and the external space of the housing 21 communicate with each other through the opening 214.

The gear case 32 shown in FIGS. 2 to 4 is attached to the first outer surface 211 from one side in the first direction so as to cover the first outer surface 211 of the housing 21. The gear case 32 is fixed to the first outer surface 211 by using a fastening member such as a screw. Specifically, between the first outer surface 211 of the housing 21 and the other side surface (inner surface) of the gear case 32 in the first direction, a developing roller gear 223, a supply roller gear 233, and a first agitator, which will be described later, are used. There is space for accommodating the gear 254, the second agitator gear 264, the coupling 24, the idle gear 27, the first drive gear 28, and the second drive gear 29. The gear case 32 is provided with a through hole 32a for exposing the coupling 24 described later. As will be described in detail later, the drive shaft of the image forming apparatus 100 is connected to the coupling 24 exposed in the through hole 32a.

The developing roller 22 is a roller that can rotate about the developing roller rotation axis extending in the first direction. As shown in FIG. 2, 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 of the housing 21 in the second direction. The developing roller 22 has a developing roller main body 221 and a developing roller shaft 222. The developing roller body 221 is a cylindrical member extending in the first direction. For example, elastic rubber is used as the material of the developing roller main body 221. The developing roller shaft 222 is a member that penetrates the developing roller main body 221 and extends in a columnar shape along the developing roller rotation axis. As the material of the developing roller shaft 222, a metal or a resin having conductivity is used.

The developing roller body 221 is fixed to the developing roller shaft 222 so as to be non-rotatable relative to the developing roller shaft 222. Further, one end of the developing roller shaft 222 in the first direction is mounted on the developing roller gear 223 so as to be non-rotatable relative to the developing roller gear 223. Therefore, when the developing roller gear 223 rotates, the developing roller shaft 222 also rotates, and the developing roller main body 221 can rotate together with the developing roller shaft 222. As shown in FIG. 1, when the developing cartridge 2 is mounted on the drum unit 1, the outer peripheral surface of the developing roller main body 221 comes into contact with the outer peripheral surface of the photoconductor drum 11.

The supply roller 23 shown in FIG. 5 is a roller that can rotate about the supply roller rotation shaft extending in the first direction. The supply roller 23 is located on the other side of the housing 21 in the third direction from the developing roller 22. Further, the supply roller 23 is located in the second direction between the first agitator rotation shaft of the first agitator 25, which will be described later, and the development roller rotation shaft of the development roller 22. The supply roller 23 has a supply roller main body 231 and a supply roller shaft 232. For example, elastic rubber is used as the material of the supply roller main body 231. The supply roller shaft 232 is a member that penetrates the supply roller main body 231 and extends in a columnar shape along the supply roller rotation axis. As the material of the supply roller shaft 232, a metal or a resin having conductivity is used.

The supply roller main body 231 is fixed to the supply roller shaft 232 so as to be non-rotatable relative to the supply roller shaft 232. Further, one end of the supply roller shaft 232 in the first direction is mounted so as not to rotate relative to the supply roller gear 233. Therefore, when the supply roller gear 233 rotates, the supply roller shaft 232 also rotates, and the supply roller main body 231 can rotate together with the supply roller shaft 232.

As shown in FIG. 5, the outer peripheral surface of the supply roller main body 231 of the supply roller 23 comes into contact with the outer peripheral surface of the developing roller main 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 via the supply roller 23. At that time, the toner is triboelectrically charged between the supply roller 23 and the developing roller 22. Further, a bias voltage is applied to the developing roller shaft 222 and the supply roller shaft 232, respectively. Therefore, the toner is attracted to and held on the outer peripheral surface of the supply roller main body 231 and the outer peripheral surface of the developing roller main body 221 by the electrostatic force between the toner and the toner.

The first agitator 25 shown in FIG. 5 is a portion capable of stirring the toner contained in the housing 21. The first agitator 25 is rotatable about a first agitator rotation axis extending in the first direction. The first agitator 25 has a first agitator shaft 251 and a first agitator blade 253. The first agitator shaft 251 is a member extending along the first agitator rotation axis. One end of the first agitator shaft 251 in the first direction is non-rotatably mounted on the first agitator gear 254 located outside the first outer surface 211 of the housing 21. As shown in FIG. 5, the first agitator shaft 251 has a substantially plate-shaped blade support portion 252. The blade support portion 252 is located in the housing 21 and extends in the first direction. The first agitator blade 253 is fixed to the blade support portion 252. The first agitator blade 253 extends radially outward with respect to the first agitator rotation axis and extends in the first direction. The first agitator blade 253 is, for example, a flexible film. The tip of the first agitator blade 253 comes into contact with 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 blade 253 also rotates with respect to the first agitator rotation shaft together with the blade support portion 252. At this time, the tip of the rotating first agitator blade 253 bends and deforms when it comes into contact with the inner surface of the housing 21.

The second agitator 26 is a portion capable of stirring the toner contained in the housing 21. The second agitator 26 is rotatable about a second agitator rotation axis extending in the first direction. As shown in FIG. 5, the second agitator 26 is located between the supply roller 23 and the first agitator 25 in the second direction. As shown in FIG. 10, the second agitator 26 has a second agitator shaft 261. The second agitator shaft 261 is a columnar member extending along the second agitator rotation axis. The second agitator shaft 261 includes a polygonal columnar (in the present embodiment) stirring unit 262. That is, the second agitator 26 is a polygonal prism that rotates about the second agitator rotation axis. The stirring unit 262 is located inside the housing 21 and extends in the first direction. In the present embodiment, the three corners of the triangular prism of the stirring unit 262 are the second agitator blades 263. One end of the second agitator shaft 261 in the first direction is mounted so as not to rotate relative to the second agitator gear 264, which will be described later. When the second agitator gear 264 rotates, the second agitator shaft 261 also rotates, and the second agitator blade 263 also rotates with respect to the second agitator rotation shaft together with the stirring unit 262.

FIG. 6 is a partially disassembled perspective view of the developing cartridge 2. As shown in FIG. 6, the developing cartridge 2 includes a coupling 24, an idle gear 27, a first drive gear 28, a second drive gear 29, and a support member 31. FIG. 7 is a view when the developing cartridge 2 is viewed from one side in the first direction, and shows a state when the gear case 32 is removed. FIG. 8 is a diagram showing a state when the coupling 24, the developing roller gear 223, and the supply roller gear 233 are removed from the state of FIG. 7. FIG. 9 is a diagram showing a state when the idle gear 27 and the first agitator gear 254 are removed from the state of FIG. FIG. 10 is a diagram showing a state when the support member 31 is removed from the state of FIG. As shown in FIGS. 7, 8 and 10, the first drive gear 28, the second drive gear 29, the first agitator gear 254, and the second agitator gear 264 are directly connected to the first outer surface 211. To position. On the other hand, as shown in FIG. 7, the developing roller gear 223, the supply roller gear 233, and the coupling 24 are attached to the first outer surface 211 via the support member 31. As shown in FIG. 8, the first idle gear portion 27a and the second idle gear portion 27c of the idle gear 27 are arranged on one side of the support member 31 in the first direction. Further, as shown in FIG. 9, the second idle gear portion 27b of the support member 31 is arranged on the other side of the support member 31 in the first direction.

6 to 11 show the development roller gear 223, the supply roller gear 233, the first agitator gear 254, the second agitator gear 264, the coupling 24, the idle gear 27, the first drive gear 28, and the second drive gear 29. The illustration of the teeth is omitted. In addition, each of these gears may transmit the rotational force by the meshing of teeth, or may transmit the rotational force by friction. For example, each of the above gears may have a rubber outer peripheral surface instead of teeth.

The coupling 24 shown in FIGS. 6 and 7 is a gear that first receives the driving force supplied from the drive shaft of the image forming apparatus 100. The coupling 24 is located on the first outer surface 211 of the housing 21 in the first direction. The coupling 24 is rotatable about a coupling shaft 241 extending in the first direction. The coupling 24 has a coupling gear portion that meshes with an idle gear 27 described later. Further, the coupling 24 also meshes with the above-mentioned developing roller gear 223 and the supply roller gear 233, respectively. With such a configuration, when the coupling 24 rotates about the coupling shaft 241 according to the driving force from the drive shaft, the idle gear 27, the developing roller gear 223, and the supply roller gear 233 that mesh with the coupling shaft 241 also rotate. The coupling 24 is rotatably supported by a support member 31 described later.

The idle gear 27 shown in FIGS. 6 to 8 is a gear for transmitting the rotation of the coupling 24 to the first agitator gear 254. The idle gear 27 is rotatable about an idle shaft 271 extending in the first direction. The idle gear 27 has a first idle gear portion 27a, a second idle gear portion 27b (see FIGS. 9 and 10), and a third idle gear portion 27c arranged in the first direction. The first idle gear portion 27a, the second idle gear portion 27b, and the third idle gear portion 27c have different radial dimensions from each other. The second idle gear portion 27b is located closer to the first outer surface 211 of the housing 21 than the first idle gear portion 27a and the third idle gear portion 27c in the first direction. Strictly speaking, the second idle gear portion 27b is housed in the recess 211a of the first outer surface 211 of the housing 21. The third idle gear portion 27c is located between the first idle gear portion 27a and the second idle gear portion 27c in the first direction. The third idle gear portion 27c meshes with the first agitator gear 254. The first idle gear portion 27a meshes with the coupling gear portion of the coupling 24. The second idle gear portion 27b meshes with the first drive gear 28 described later.

The drive gears 28 and 29 shown in FIG. 10 are gears for transmitting the rotation of the idle gear 27 to the second agitator gear 264. The first drive gear 28 is rotatable about a first drive shaft 281 extending in the first direction. The first drive gear 28 meshes with the second idle gear portion 27b of the idle gear 27. The first drive gear 28 is housed in the recess 211a of the first outer surface 211 of the housing 21. The second drive gear 29 is rotatable about a second drive shaft 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 the recess 211a of the first outer surface 211 of the housing 21.

The support member 31 shown in FIGS. 8 and 9 is a member that rotatably supports the coupling 24. The support member 31 has a substantially planar shape extending in the second direction and the third direction. As shown in FIG. 6, the support member 31 has a cylindrical portion 31a. The cylindrical portion 31a is a cylindrical portion that protrudes in the first direction from the plane on one side in the first direction of the support member 31. The cylindrical portion 31a is inserted into the coupling 24. As a result, the coupling 24 is rotatably supported on one side of the support member 31 in the first direction. The support member 31 partitions an area within the gear case 32. Specifically, the above-mentioned developing roller gear 223 and supply roller gear 233 are arranged together with the coupling 24 in the region on one side of the support member 31 in the first direction. The support member 31 is provided with a circular hole for passing the developing roller shaft 222 and the supply roller shaft 232, respectively. On the other hand, in the region on the other side of the support member 31 in the first direction, the first drive gear 28, the second drive gear 29, and the second agitator gear 264 are arranged. Specifically, in a state where the drive gears 28, 29 and the second agitator gear 264 are housed in the recess 211a of the first outer surface 211 of the housing 21, the recess 211a is a support member 31 from one side in the first direction. Partially covered with. The recess 211a is recessed from the first outer surface 211 to the other side in the first direction. The second idle gear portion 27b of the idle gear 27 is also housed in the recess 211a.

FIG. 11 shows a state when the drive gears 28 and 29 and the second agitator gear 264 are removed from the state of FIG. As shown in FIGS. 6 and 11, from the bottom surface of the recess 211a, a support shaft for rotatably supporting each of the idle gear 27, the first drive gear 28, and the second drive gear 29 is in the first direction. It protrudes to one side. Further, the bottom of the recess 211a is provided with a through hole for filling the inside of the housing 21 with toner. A seal member 266 is housed in this through hole, and a second agitator gear 264 is arranged on one side of the seal member 266 in the first direction. In this way, by arranging the second agitator gear 264 on the hole portion via the seal member 266, leakage of toner from the inside of the housing 21 is prevented.

In the image forming apparatus 100 having the above configuration, when the coupling 24 rotates with respect to the coupling shaft 241 according to the driving force from the drive shaft, the developing roller shaft 222, the supply roller shaft 232, and the idle gear 27 that mesh with the coupling shaft 241 are used. Rotates. Further, as the idle gear 27 rotates, the first agitator gear 254 that meshes with the idle gear 27 also rotates. Further, as the idle gear 27 rotates, the first drive gear 28 that meshes with the idle gear 27 also rotates. When the first drive gear 28 rotates, the second drive gear 29 that meshes with the first drive gear 28 rotates, and the second agitator gear 264 that meshes with the second drive gear 29 also rotates with the rotation of the second drive gear 29. When each of the above gears meshes, the second agitator gear 264 rotates at a rotation speed higher than that of the first agitator gear 254, depending on the number of teeth of each gear. In the present embodiment, the rotation speed of the second agitator gear 264 is about 3 to 4 times the rotation speed of the first agitator gear 254. However, the number of teeth and the diameter dimension of each gear are set so that the peripheral speed of the second agitator 26 is the same as or faster than the peripheral speed of the supply roller 23.

No gear is interposed between the idle gear 27 and the first agitator gear 254. On the other hand, an even number of drive gears 28 and 29 are interposed between the idle 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 (in the present embodiment, clockwise when viewed from one side of the first direction).

At the time of printing processing in the image forming apparatus 100, first, the outer peripheral surface of the photoconductor drum 11 is uniformly charged and then exposed by laser light or LED light, so that an input image is input to the outer peripheral surface of the photoconductor drum 11. An electrostatic latent image based on the data is formed. Further, the toner in the housing 21 is first supplied to the outer peripheral surface of the supply roller 23 while being agitated by the rotating first agitator 25 and the second agitator 26, and then from the outer peripheral surface of the supply roller 23 to the developing roller 22. It is supplied to the outer peripheral surface. Then, as the developing roller 22 rotates, the toner is supported in a thin layer on the outer peripheral surface of the developing roller main body 221 of the developing roller 22.

The toner carried on the outer peripheral surface of the developing roller 22 is supplied from the outer peripheral surface of the developing roller 22 to the electrostatic latent image formed on the outer peripheral surface of the photoconductor drum 11. As a result, the electrostatic latent image is made into a visible image, and a toner image is formed on the outer peripheral surface of the photoconductor drum 11. After this toner image is transferred to the recording surface of the printing paper, it is heat-fixed and the printing process is completed.

As described above, the developing cartridge 2 of the present 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 locus of the second agitator blade 263 of the second agitator 26 is located outside the rotation locus of the first agitator blade 253 of the first agitator 25. As a result, the toner in the region of the internal space of the housing 21 in which the toner cannot be agitated only by the rotation of the first agitator 25 can be agitated by rotating the second agitator 26. Therefore, even when the amount of toner remaining in the internal space of the housing 21 is low, the toner can be satisfactorily agitated.

Further, in the developing cartridge 2 of the present embodiment, as shown in FIG. 5, the second agitator 26 is closer to the supply roller 23 than the first agitator 25 in the second direction. As a result, the toner staying around the supply roller 23 can be agitated by rotating the second agitator 26. Therefore, it is possible to suppress the stagnation of the toner flow around the supply roller 23 in the internal space of the housing 21.

Further, in the developing cartridge 2 of the present embodiment, the first agitator 25 and the second agitator 26 rotate in the same direction. This makes it easier for the toner flow formed by the rotation of the second agitator 26 to join the toner flow formed by the rotation of the first agitator 25. As a result, the toner staying in the housing 21 can be taken into the stirring region of the first agitator 25, and the entire toner can be well stirred.

Further, the developing cartridge 2 of the present embodiment includes a coupling 24, a developing roller gear 223, a supply roller gear 233, a first agitator gear 254, a second agitator gear 264, an idle gear 27, and a first drive gear 28. And a second drive gear 29. The developing cartridge 2 includes an even number of drive gears 28 and 29. This makes it possible to rotate the first agitator 25 and the second agitator 26 at a constant speed ratio. Further, the first agitator 25 and the second agitator 26 rotate in the same direction when viewed in the first direction. Therefore, the flow of toner formed by being agitated by the second agitator 26 is likely to join the flow of toner formed by being agitated by the first agitator 25. From another point of view, the rotation direction of the second agitator 26 and the rotation of the supply roller 23 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 direction is the same. As a result, by rotating the second agitator 26, it becomes easy to supply toner to the outer peripheral surface of the supply roller 23.

Further, in the developing cartridge 2 of the present embodiment, the developing roller gear 223 and the supply roller gear 233 are arranged on one side in the first direction of the support member 31. On the other hand, the drive gears 28 and 29 and the second agitator gear 264 are arranged on the other side of the support member 31 in the first direction. As a result, the developing roller gear 223, the supply roller gear 233, the drive gears 28, 29, and the second agitator gear 264 can be arranged by distributing the support member 31 to one side and the other side in the first direction. As a result, many gears can be laid out in a narrow space. Therefore, the size of the developing cartridge 2 can be reduced.

Further, in the developing cartridge 2 of the present embodiment, the first outer surface 211 of the housing 21 has a recess 211a recessed on the other side in the first direction. The drive gears 28 and 29 and the second agitator gear 264 are housed in the recess 211a. As a result, the drive gears 28 and 29 and the second agitator gear 264 are additionally housed in the gear case 32 with almost no change in the arrangement of the conventional coupling 24, the developing roller gear 223, the supply roller gear 233, and the like. Can be done. Therefore, the second agitator 26 having the present configuration can be easily introduced into the developing cartridge 2.

Further, in the developing cartridge 2 of the present embodiment, the rotation speed of the second agitator 26 is higher than the rotation speed of the first agitator 25. Further, the diameter of the second agitator blade 263 centered on the second agitator rotation axis is smaller than the diameter of the first agitator blade 253 centered on the first agitator rotation axis. As a result, the toner retained in the internal space of the housing 21 can be easily guided to a wide stirring region of the first agitator 25 by the rotation of the second agitator 26 which rotates smaller and faster than the first agitator 25. ..

Further, in the developing cartridge 2 of the present embodiment, the peripheral speed of the second agitator 26 (moving speed of the second agitator blade 263) is the peripheral speed of the supply roller 23 (moving speed of the outer peripheral surface of the supply roller main body 231). Same or faster. This makes it possible to prevent the amount of toner supplied to the supply roller 23 from becoming insufficient.

Further, in the developing cartridge 2 of the present embodiment, the first agitator blade 253 and the second agitator blade 263 do not come into contact with each other. As a result, it is possible to prevent a complicated toner flow from occurring in the internal space of the housing 21 due to interference between the first agitator blade 253 and the second agitator blade 263. As a result, it becomes easy to uniformly stir the toner.

Further, in the developing cartridge 2 of the present embodiment, the first agitator blade 253 is a sheet-shaped film. As a result, by rotating the first agitator 25, the tip of the first agitator blade 253 can be brought into contact with the inner surface of the housing 21 to be bent, and the toner adhering to the inner surface of the housing 21 can be scraped off. .. As a result, the toner can be mixed more uniformly in the housing 21. In other words, toner retention can be suppressed in the entire internal space of the housing 21.

Further, in the developing cartridge 2 of the present embodiment, the second agitator 26 is a polygonal prism, and the second agitator blade 263 is a plurality of corners of the polygonal prism. Thereby, the second agitator blade 263 having high rigidity can be realized.

<4. Modification example>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. In the following, some modifications will be briefly described.

In the above embodiment, the second agitator 26 is a triangular columnar shape that rotates about the second agitator rotation axis, but the shape of the second agitator 26 is not limited to this. Instead of the above, for example, the second agitator may be a pentagonal column or a hexagonal column.

Furthermore, the shape of the second agitator is not limited to the polygonal columnar shape. For example, the second agitator blade of the second agitator may have a plurality of blade portions protruding radially outward from the outer peripheral portion of the rotating body that rotates about the second agitator rotation axis. The blade portion may be flat or curved. With such a configuration, the surface area of the second agitator blade increases. As a result, the toner retained in the internal space of the housing 21 can be satisfactorily agitated by the second agitator blade.

In the above embodiment, the first agitator blade 253 is a sheet-like film. However, instead of this, the first agitator blade may be a thin plastic plate.

The development roller gear 223, the supply roller gear 233, the first agitator gear 254, and the second agitator gear 264 are coupled to the second outer surface 212, which is the outer surface on the other side of the housing 21 in the first direction. 24, an idle gear 27, a first drive gear 28, and a second drive gear 29 may be arranged.

Further, the details of the configuration of the developing cartridge may be appropriately changed as long as the gist of the present invention is not deviated. Further, the elements appearing in the above-described embodiments and modifications may be appropriately combined as long as there is no contradiction.

1 Drum unit 2 Development cartridge 11 Photoreceptor drum 12 Frame 21 Housing 22 Development roller 23 Supply roller 24 Coupling 25 1st agitator 26 2nd agitator 27 Idle gear 27b 2nd idle gear part 28 1st drive gear 29 2nd drive gear 31 Support member 32 Gear case 32a Through hole 100 Image forming device 101 Main body casing 102 Control unit 120 Development cartridge holding part 211 First outer surface 211a Recessed 212 Second outer surface 214 Opening 221 Development roller body 222 Development roller shaft 223 Development roller gear 231 Supply Roller body 232 Supply roller shaft 233 Supply roller gear 241 Coupling shaft 251 1st agitator shaft 252 Blade support 253 1st agitator blade 254 1st agitator gear 261 2nd agitator shaft 262 Stirring part 263 2nd agitator blade 264 2nd agitator gear 266 Seal member

Claims (22)

A housing that can store toner and
A developing roller that can rotate about the axis of rotation of the developing roller that extends in the first direction,
A first agitator capable of stirring the toner, and a first agitator rotatable about a rotation axis of the first agitator extending in the first direction.
A supply roller located between the first agitator and the developing roller, which is rotatable about a supply roller rotating shaft extending in the first direction, can supply the toner to the outer peripheral surface of the developing roller. Supply rollers and
A second agitator located between the supply roller and the first agitator, which is rotatable about a second agitator rotation axis extending in the first direction, and a second agitator.
Equipped with
A developing cartridge characterized in that the rotation locus of the second agitator is located outside the rotation locus of the first agitator. The developing cartridge according to claim 1.
A developing cartridge characterized in that the outer peripheral surface of the supply roller is in contact with the outer peripheral surface of the developing roller. The developing cartridge according to claim 1 or 2.
The supply roller is a developing cartridge characterized in that it is located between the first agitator and the developing roller in a second direction connecting the first agitator rotating shaft and the developing roller rotating shaft. The developing cartridge according to claim 3.
The second agitator is a developing cartridge characterized in that it is located between the supply roller and the first agitator in the second direction. The developing cartridge according to claim 4.
A developing cartridge, characterized in that, in the second direction, the second agitator is closer to the supply roller than the first agitator. The developing cartridge according to any one of claims 1 to 5.
The first agitator and the second agitator are development cartridges characterized in that they rotate in the same direction. The developing cartridge according to any one of claims 1 to 6.
A coupling that is located on the outer surface of one side of the housing in the first direction and is rotatable about a coupling shaft extending in the first direction and has a coupling gear portion.
A developing roller gear that can rotate together with the developing roller according to the rotation of the coupling, and a developing roller gear located on the outer surface of the housing.
A supply roller gear that can rotate together with the supply roller according to the rotation of the coupling, and is a supply roller gear located on the outer surface of the housing.
A first agitator gear that can rotate with the first agitator, and a first agitator gear located on the outer surface of the housing.
A second agitator gear that is rotatable together with the second agitator and is located on the outer surface of the housing. In the first direction, the outer surface of the housing is more than the coupling. A second agitator gear located in the vicinity of, wherein at least a portion of the second agitator gear is located between the coupling and the outer surface of the housing in the first direction. With gears
An idle gear that can rotate according to the rotation of the coupling.
The first idle gear portion that meshes with the coupling gear portion and
A second idle gear portion located closer to the outer surface of the housing than the first idle gear portion in the first direction.
With idle gear and
The first drive gear that meshes with the second idle gear portion and
A second drive gear that meshes with the first drive gear, and a second drive gear that meshes with the second agitator gear.
A developing cartridge characterized by being equipped with. The developing cartridge according to any one of claims 1 to 6.
A coupling that is located on the outer surface of one side of the housing in the first direction and is rotatable about a coupling shaft extending in the first direction and has a coupling gear portion.
A developing roller gear that can rotate together with the developing roller according to the rotation of the coupling, and a developing roller gear located on the outer surface of the housing.
A supply roller gear that can rotate with the supply roller as the coupling rotates, and is a supply roller gear located on the outer surface of the housing.
A first agitator gear that can rotate with the first agitator, and a first agitator gear located on the outer surface of the housing.
A second agitator gear that is rotatable together with the second agitator and is located on the outer surface of the housing. In the first direction, the outer surface of the housing is more than the coupling. A second agitator gear located in the vicinity of, wherein at least a portion of the second agitator gear is located between the coupling and the outer surface of the housing in the first direction. With gears
An idle gear that can rotate according to the rotation of the coupling.
The first idle gear portion that meshes with the coupling gear portion and
A second idle gear portion located closer to the outer surface of the housing than the first idle gear portion in the first direction.
With idle gear and
An even number of drive gears that transmit driving force from the second idle gear portion to the second agitator gear,
A developing cartridge characterized by being equipped with. The developing cartridge according to claim 7 or 8.
The development cartridge is characterized in that the coupling is rotatable about the coupling shaft in response to receiving a driving force. The developing cartridge according to any one of claims 7 to 9.
The developing roller includes a developing roller shaft extending in the first direction.
The developing roller gear is a developing cartridge that is mounted on the developing roller shaft and can rotate together with the developing roller shaft. The developing cartridge according to any one of claims 7 to 10.
The supply roller comprises a supply roller shaft extending in the first direction.
The developing cartridge, wherein the supply roller gear is mounted on the supply roller shaft and can rotate together with the supply roller shaft. The developing cartridge according to any one of claims 7 to 11.
The first agitator includes a first agitator shaft extending in the first direction.
The first agitator gear is a developing cartridge that is mounted on the first agitator shaft and is rotatable together with the first agitator shaft. The developing cartridge according to any one of claims 7 to 12.
The second agitator includes a second agitator shaft extending in the first direction.
The second agitator gear is a developing cartridge that is mounted on the second agitator shaft and is rotatable together with the second agitator shaft. The developing cartridge according to any one of claims 7 to 13.
A planar support member extending in the second direction and a third direction intersecting the first direction and the second direction, and the cup on one side of the support member in the first direction. It also has a support member that rotatably supports the ring.
The developing roller gear and the supply roller gear are arranged on one side of the support member in the first direction.
A developing cartridge, characterized in that the drive gear and the second agitator gear are arranged on the other side of the support member in the first direction. The developing cartridge according to any one of claims 7 to 14.
The outer surface of the housing has a recess recessed on the other side of the first direction.
A developing cartridge, characterized in that the drive gear and the second agitator gear are housed in the recess. The developing cartridge according to any one of claims 1 to 15.
A developing cartridge characterized in that the rotation speed of the second agitator is higher than the rotation speed of the first agitator. The developing cartridge according to any one of claims 1 to 16.
A developing cartridge characterized in that the peripheral speed of the second agitator is equal to or faster than the peripheral speed of the supply roller. The developing cartridge according to any one of claims 1 to 17.
The first agitator has a first agitator blade that rotates about the first agitator rotation axis.
The second agitator has a second agitator blade that rotates about the second agitator rotation axis.
A developing cartridge characterized in that the first agitator blade and the second agitator blade do not come into contact with each other. The developing cartridge according to claim 18.
The first agitator blade is a developing cartridge characterized by being a sheet-shaped film. The developing cartridge according to claim 18 or 19.
The second agitator is a polygonal prism that rotates about the second agitator rotation axis.
The second agitator blade is a developing cartridge, characterized in that it is a plurality of corners of the polygonal prism. The developing cartridge according to claim 18 or 19.
The second agitator blade is a developing cartridge having a plurality of blade portions protruding radially outward from an outer peripheral portion of a rotating body that rotates about the second agitator rotation axis. The developing cartridge according to any one of claims 18 to 21.
A developing cartridge characterized in that the diameter of the second agitator blade centered on the second agitator rotation shaft is smaller than the diameter of the first agitator blade centered on the first agitator rotation shaft.

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