JP2021117386A - Developing cartridge - Google Patents

Abstract

To provide a developing cartridge with a structure including fewer components.SOLUTION: This developing cartridge includes a development electrode 60B, a first lever 110B, and a holder 120B. The holder 120B prevents the first lever 110B from being extracted from one side to the other side in a third direction. The first lever 110B stops the rotation of the development electrode 60B from one side to the other side in the third direction. Thus, it is unnecessary to provide a component to stop the rotation of the development electrode 60B from one side to the other side in the third direction besides the first lever 110B and the holder 120B. Thereby, the number of components of the developing cartridge can be reduced.SELECTED DRAWING: Figure 15

Description

The present disclosure relates to a developing cartridge.

Conventionally, electrophotographic image forming devices such as laser printers and LED printers are known. A developing cartridge is used as the image forming apparatus. The developing cartridge has a developing roller for supplying a developing agent. A conventional image forming apparatus is described in, for example, Patent Document 1.

The developing cartridge of Patent Document 1 is attached to the drum cartridge. The drum cartridge has a photoconductor drum. When the developing cartridge is mounted on the drum cartridge, the photoconductor drum and the developing roller come into contact with each other. Then, the drum cartridge to which the developing cartridge is mounted is mounted on the image forming apparatus.

Japanese Unexamined Patent Publication No. 2013-54058

The developing cartridge has a member for positioning the developing roller with respect to the photoconductor drum. Further, the developing cartridge has a developing electrode for supplying a bias voltage to the shaft of the developing roller. Further, the developing cartridge has a member that receives a pressing force when the developing roller is separated from the photoconductor drum. However, if the member for positioning the developing roller, the developing electrode for supplying the bias voltage to the shaft of the developing roller, and the member for receiving the pressing force at the time of separation are separately provided, the number of parts of the developing cartridge increases.

An object of the present disclosure is to provide a structure capable of reducing the number of parts in a developing cartridge.

The first disclosure of the present application is a developing cartridge, a developing roller having a developing roller shaft extending in the first direction, and a casing capable of accommodating a developing agent, in a second direction intersecting with the first direction. It has a casing in which the developing roller is located at one end, a first end that is electrically connected to the developing roller shaft, and a second end that is farther from the developing roller shaft than the first end. A developing electrode that is movable together with the casing and the developing roller, wherein the second end is a developing electrode that is more distant from the one end of the casing in the second direction than the first end. A developing electrode that is rotatable about the developing roller shaft, a first lever that is movable with respect to the casing, and a holder that movably holds the first lever with respect to the casing are provided. While holding the first lever, the holder prevents the first lever from coming out of the holder from one side to the other in the third direction intersecting the first direction and the second direction. Stop, the first lever is characterized in that the rotation of the developing electrode from one side to the other in the third direction is stopped.

The second disclosure of the present application is the developing cartridge of the first disclosure, in which the holder is from one side to the other in a third direction intersecting the first direction and the second direction of the first lever. It is characterized by stopping the movement of.

The third disclosure of the present application is the developing cartridge of the second disclosure, wherein the first lever has one end and the other end separated from the one end toward the other side in the third direction. The one end portion has a first convex portion protruding in the first direction, and the holder comes into contact with the first convex portion so that the first lever comes into contact with the first convex portion from one side to the other side in the third direction. It is characterized by stopping the movement to.

The fourth disclosure of the present application is the developing cartridge of the third disclosure, wherein the developing electrode is a first hole extending in the third direction between the first end portion and the second end portion. The other end of the first lever has a first hole into which the other end is inserted, and the other end comes into contact with the developing electrode from one side to the other in the third direction of the developing electrode. It is characterized in that the rotation of the is stopped.

The fifth disclosure of the present application is the developing cartridge of the fourth disclosure, wherein the developing electrode has a lever receiving portion located inside the first hole, and the first lever is said from the other end portion. It has a second convex portion that protrudes in the first direction, and the second convex portion rotates from one side to the other side in the third direction of the developing electrode by contacting the lever receiving portion. It is characterized by stopping.

The sixth disclosure of the present application is a developing cartridge according to any one of the first to fifth disclosures, wherein the casing has a casing protrusion extending in the first direction, and the casing protrusion is a developing electrode. It is characterized in that the rotation from the other side to the one side in the third direction is stopped.

The seventh disclosure of the present application is the development cartridge of the sixth disclosure, wherein the development electrode has an electrode protrusion extending in the first direction, and the casing protrusion comes into contact with the electrode protrusion to develop the development. It is characterized in that the rotation of the electrode from the other side to the one side in the third direction is stopped.

The eighth disclosure of the present application is a developing cartridge according to any one of the first to seventh disclosures, the developing roller shaft has an annular engaging groove on the outer peripheral surface, and the developing electrode is a developing electrode. It has a first insertion hole into which the developing roller shaft is inserted, and a wall portion protruding from a part of the peripheral edge of the first insertion hole toward the engaging groove, and is engaged with the developing electrode. When the first lever is held by the holder, the wall portion is inserted into the engaging groove.

The ninth disclosure of the present application is a developing cartridge according to any one of the first to eighth disclosures, wherein the developing electrode is attached to one end of the developing roller shaft in the first direction, and the developing cartridge is attached. Is a bearing mounted on the other end of the developing roller shaft in the first direction, and has a third end having a second insertion hole into which the other end of the developing roller shaft is inserted, and the first. It has a fourth end portion that is separated from the developing roller shaft than the three end portions, and further includes a casing and a bearing that can move together with the developing roller.

The tenth disclosure of the present application is the development cartridge of the ninth disclosure, wherein the bearing has a second hole extending in the first direction between the third end portion and the fourth end portion, and the second hole. The casing has a claw bearing portion located inside the hole, and the casing is a claw portion extending in the first direction, the tip of which protrudes in a direction intersecting with the first direction, and the claw bearing portion. It is characterized by having a claw portion that engages with the portion.

The eleventh disclosure of the present application is the developing cartridge of the tenth disclosure, in which the bearing is rotatable with respect to the developing roller shaft, and the claw portion is brought into contact with the bearing to rotate the bearing. It is characterized by stopping.

The twelfth disclosure of the present application is a developing cartridge according to any one of the ninth to eleventh disclosures, wherein the developing cartridge is used for a drum cartridge having a photoconductor drum, and the drum cartridge is the same. The bearing has a pressure-sensitive projection that projects in a direction away from the casing and has a pressure-pressed protrusion that can come into contact with the separation lever. It is characterized by.

According to the first to twelfth disclosures of the present application, the holder stops the movement of the first lever from one side to the other in the third direction. Further, the first lever stops the rotation of the developing electrode from one side to the other in the third direction. Therefore, apart from the first lever and the holder, it is not necessary to provide a component for stopping the rotation of the developing electrode from one side to the other in the third direction. Therefore, the number of parts of the developing cartridge can be reduced.

Further, according to the eighth disclosure of the present application, the developing roller shaft can be inserted into the first insertion hole when the first lever engaged with the developing electrode is not held by the holder. On the other hand, in a state where the first lever engaged with the developing electrode is held by the holder, the wall portion is inserted into the engaging groove. Therefore, when the developing cartridge is manufactured, the developing roller shaft can be inserted into the developing electrode, and when the developing cartridge is used, the developing electrode can be prevented from coming off from the developing roller shaft.

Further, according to the tenth disclosure of the present application, the bearing is held by the claw portion extending in the first direction from the casing. As a result, the bearing can be held without providing an engaging groove on the developing roller shaft.

Further, according to the eleventh disclosure of the present application, it is not necessary to provide a component for stopping the rotation of the bearing separately from the claw portion.

It is a perspective view of a developing cartridge and a drum cartridge. It is a perspective view of a developing cartridge. It is a perspective view of a developing cartridge. It is an exploded perspective view of the developing cartridge in the vicinity of the first outer surface of a casing. It is an exploded perspective view of the developing cartridge in the vicinity of the second outer surface of a casing. It is a figure which looked at the state when a developing cartridge is attached to a drum cartridge from one side of the 1st direction. It is a figure which looked at the state when a developing cartridge is attached to a drum cartridge from one side of the 1st direction. It is a figure which looked at the state when a developing cartridge is attached to a drum cartridge from one side of the 1st direction. It is sectional drawing of the development cartridge and the drum cartridge in the state which the development cartridge is attached to the drum cartridge. It is sectional drawing of the development cartridge and the drum cartridge at the time of the separation operation. It is sectional drawing of the development cartridge and the drum cartridge at the time of removing a development cartridge from a drum cartridge. It is a perspective view of a developing cartridge and a drum cartridge. It is a perspective view of a developing cartridge and a drum cartridge. It is a perspective view of a developing cartridge and a drum cartridge. It is a perspective view of the developing cartridge in the vicinity of the first outer surface of a casing. It is an exploded perspective view of the developing cartridge in the vicinity of the first outer surface of a casing. It is a perspective view of the developing cartridge in the vicinity of the 2nd outer surface of a casing. It is an exploded perspective view of the developing cartridge in the vicinity of the second outer surface of a casing. It is a figure which showed the cross section of the 1st bearing and the side surface of the 1st lever. It is a figure which showed the state when the 1st bearing, the 1st lever, and the holder are attached to the developing cartridge. It is a figure which showed the state when the 1st bearing, the 1st lever, and the holder are attached to the developing cartridge. It is a partial cross-sectional view of the developing cartridge in the vicinity of the 2nd bearing. It is a figure which looked at the state when a developing cartridge is attached to a drum cartridge from one side of the 1st direction. It is a figure which looked at the state when a developing cartridge is attached to a drum cartridge from one side of the 1st direction. It is a figure which looked at the development cartridge and the drum cartridge after mounting from one side of the 1st direction. It is a figure which looked at the development cartridge and the drum cartridge at the time of the separation operation from one side of the 1st direction. It is a figure which looked at the development cartridge and the drum cartridge after mounting from the other side of the 1st direction. It is a figure which looked at the development cartridge and the drum cartridge at the time of the separation operation from the other side of the 1st direction.

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

In the following, the direction in which the developing roller 30 of the developing cartridge 1 extends is referred to as a "first direction". Further, the direction in which the agitator 20 of the developing cartridge 1 and the developing roller 30 are aligned is referred to as a "second direction". The first direction and the second direction intersect each other (preferably orthogonally).

<1. First Embodiment>
<1-1. Overview of developing cartridges and drum cartridges>
FIG. 1 is a perspective view of the developing cartridge 1 and the drum cartridge 2. FIG. 1 shows a state in which the developing cartridge 1 is mounted on the drum cartridge 2. The developing cartridge 1 and the drum cartridge 2 are used in an electrophotographic image forming apparatus. The image forming apparatus is, for example, a laser printer or an LED printer.

As shown in FIG. 1, the developing cartridge 1 is used together with the drum cartridge 2. The developing cartridge 1 can be attached to the drum cartridge 2. The developing cartridge 1 is mounted on the image forming apparatus in a state of being mounted on the drum cartridge 2. The image forming apparatus can be equipped with, for example, four developing cartridges 1. The four developing cartridges 1 contain developing agents (eg, toner) of different colors (eg, cyan, magenta, yellow, and black). The image forming apparatus forms an image on the recording surface of the printing paper by the developing agent supplied from the developing cartridge 1. However, the number of development cartridges 1 that can be attached to the image forming apparatus may be 1 to 3, or 5 or more.

<1-2. Development cartridge structure>
2 and 3 are perspective views of the developing cartridge 1. FIG. 4 is an exploded perspective view of the developing cartridge 1 in the vicinity of the first outer surface 11 of the casing 10. FIG. 5 is an exploded perspective view of the developing cartridge 1 in the vicinity of the second outer surface 12 of the casing 10. As shown in FIGS. 1 to 5, the developing cartridge 1 includes a casing 10, an agitator 20, a developing roller 30, a supply roller 40, a gear portion 50, a first bearing 60, a first lever 110, a holder 120, and a second bearing 70. , And a second lever 130.

The casing 10 is a casing capable of accommodating the developer. The casing 10 has a first outer surface 11 and a second outer surface 12. The first outer surface 11 is located at one end of the casing 10 in the first direction. The second outer surface 12 is located at the other end of the casing 10 in the first direction. The first outer surface 11 and the second outer surface 12 are separated from each other in the first direction. The casing 10 extends in the first direction between the first outer surface 11 and the second outer surface 12 and also extends in the second direction.

A storage chamber 13 is provided inside the casing 10. The developer is housed in the storage chamber 13. Further, the casing 10 has an opening 14. The opening 14 is located at one end of the casing 10 in the second direction. The external space of the casing 10 and the accommodation chamber 13 communicate with each other through the opening 14. The casing 10 may have a handle on the outer surface of the other end in the second direction.

The agitator 20 has an agitator shaft 21 and blades 22. The agitator shaft 21 extends along the first direction. The blades 22 extend from the agitator shaft 21 toward the inner surface of the casing 10. A part of the agitator shaft 21 and the blades 22 are arranged in the accommodating chamber 13 of the casing 10. An agitator gear (not shown) included in the gear portion 50 is attached to the end portion of the agitator shaft 21 in the first direction. The agitator shaft 21 is fixed to the agitator gear so as not to rotate relative to the agitator gear. When the agitator gear rotates, the agitator shaft 21 and the blades 22 rotate about a rotation shaft extending in the first direction. Then, the developer in the accommodating chamber 13 is agitated by the rotation of the blade 22.

The developing roller 30 is a roller that can rotate about the rotation axis A1 extending in the first direction. The developing roller 30 is located in the opening 14 of the casing 10. That is, the developing roller 30 is located at one end of the casing 10 in the second direction. The developing roller 30 has a developing roller main body 31 and a developing roller shaft 32. The developing roller body 31 is a cylindrical member extending in the first direction. As the material of the developing roller main body 31, for example, elastic rubber is used. The developing roller shaft 32 is a columnar member that penetrates the developing roller main body 31 and extends in the first direction. The developing roller shaft 32 is conductive. As the material of the developing roller shaft 32, a metal or a resin having conductivity is used.

The developing roller body 31 is fixed to the developing roller shaft 32 so as not to rotate relative to the developing roller shaft 32. Further, the developing roller gear 51 included in the gear portion 50 is attached to the end portion of the developing roller shaft 32 in the first direction. The developing roller shaft 32 is fixed to the developing roller gear 51 so as not to rotate relative to the developing roller gear 51. Therefore, when the developing roller gear 51 rotates, the developing roller shaft 32 also rotates, and the developing roller main body 31 also rotates together with the developing roller shaft 32.

The developing roller shaft 32 does not have to penetrate the developing roller main body 31 in the first direction. For example, the developing roller shaft 32 may extend in the first direction from both ends of the developing roller main body 31 in the first direction.

The supply roller 40 is a roller that can rotate about a rotation axis extending in the first direction. The supply roller 40 is located between the agitator 20 and the developing roller 30. The supply roller 40 has a supply roller main body 41 and a supply roller shaft 42. The supply roller main body 41 is a cylindrical member extending in the first direction. As the material of the supply roller main body 41, for example, elastic rubber is used. The supply roller shaft 42 is a columnar member that penetrates the supply roller body 41 and extends in the first direction.

The supply roller body 41 is fixed to the supply roller shaft 42 so as not to rotate relative to the supply roller shaft 42. Further, a supply roller gear (not shown) included in the gear portion 50 is attached to the end portion of the supply roller shaft 42 in the first direction. The supply roller shaft 42 is fixed so as not to rotate relative to the supply roller gear. Therefore, when the supply roller gear rotates, the supply roller shaft 42 also rotates, and the supply roller main body 41 also rotates together with the supply roller shaft 42.

The supply roller shaft 42 does not have to penetrate the supply roller main body 41 in the first direction. For example, the supply roller shaft 42 may extend in the first direction from both ends of the supply roller main body 41 in the first direction.

When the developing cartridge 1 receives the driving force, the developing agent is supplied from the accommodation chamber 13 in the casing 10 to the outer peripheral surface of the developing roller 30 via the supply roller 40. At that time, the developer is triboelectrically charged between the supply roller 40 and the developing roller 30. On the other hand, a bias voltage is applied to the developing roller shaft 32 of the developing roller 30. Therefore, the developer is attracted to the outer peripheral surface of the developing roller main body 31 by the electrostatic force between the developing roller shaft 32 and the developing agent.

Further, the developing cartridge 1 has a layer thickness regulating blade (not shown). The layer thickness regulating blade forms the developer supplied to the outer peripheral surface of the developing roller main body 31 to a constant thickness. After that, the developer on the outer peripheral surface of the developing roller body 31 is supplied to the photoconductor drum 92 described later in the drum cartridge 2. At this time, the developer moves from the developing roller main body 31 to the photoconductor drum 92 according to the electrostatic latent image formed on the outer peripheral surface of the photoconductor drum 92. As a result, the electrostatic latent image is visualized on the outer peripheral surface of the photoconductor drum 92.

The gear portion 50 is located on the second outer surface 12 of the casing 10. As shown in FIG. 5, the gear portion 50 includes the above-mentioned agitator gear, developing roller gear 51, supply roller gear, a plurality of idle gears, a coupling 52, and a gear cover 53. The gear cover 53, together with the casing 10, constitutes the housing of the developing cartridge 1. The gear cover 53 is fixed to the second outer surface 12 of the casing 10, for example, by screwing. At least a portion of the plurality of gears is located between the second outer surface 12 and the gear cover 53.

The gear cover 53 has a cylindrical collar 531 that projects in the first direction. The coupling 52 is housed inside the collar 531. The coupling 52 has an engaging portion 521 that is recessed in the first direction. The engaging portion 521 is exposed from the gear cover 53. When the developing cartridge 1 mounted on the drum cartridge 2 is mounted on the image forming apparatus, the drive shaft of the image forming apparatus is connected to the engaging portion 521 of the coupling 52. Then, the rotation of the drive shaft is transmitted to the agitator gear, the plurality of idle gears, the developing roller gear 51, and the supply roller gear via the coupling 52.

The plurality of gears included in the gear portion 50 may transmit the rotational force by the meshing of the teeth, or may transmit the rotational force by friction.

The first bearing 60 is located on the first outer surface 11 of the casing 10. The first bearing 60 rotatably supports one end of the developing roller shaft 32 in the first direction. As shown in FIG. 4, the first bearing 60 has a first end portion 61 and a second end portion 62. The second end 62 is farther from the developing roller shaft 32 than the first end 61. Further, the second end portion 62 is separated from the first end portion 61 in the second direction from one end of the casing 10 in the second direction. The first bearing 60 extends between the first end 61 and the second end 62 along the first outer surface 11 of the casing 10.

The first bearing 60 has a first arm 63 and a second arm 64. The second arm 64 is farther from the developing roller shaft 32 than the first arm 63. Further, the second arm 64 is separated from the first arm 63 in the second direction from one end of the casing 10 in the second direction. The first arm 63 has the first end portion 61 described above. The second arm 64 has the second end 62 described above. The first arm 63 extends, for example, linearly along the first outer surface 11 of the casing 10. The second arm 64 extends, for example, linearly along the first outer surface 11 of the casing 10. However, the first arm 63 is bent with respect to the second arm 64. The angle formed by the first arm 63 and the second arm 64 is an obtuse angle.

In the present embodiment, the first arm 63 and the second arm 64 are integrally molded. However, the first arm 63 and the second arm 64 may be separate parts. In that case, the first arm 63 and the second arm 64 may be fixed to each other.

The first bearing 60 has a first insertion hole 65. The first insertion hole 65 extends in the first direction at the first end 61 of the first bearing 60. The first insertion hole 65 may be a through hole that penetrates the first end portion 61 in the first direction, or may not penetrate the first end portion 61. The first insertion hole 65 has a cylindrical inner peripheral surface. One end of the developing roller shaft 32 in the first direction is inserted into the first insertion hole 65. As a result, the first bearing 60 is mounted on one end of the developing roller shaft 32 in the first direction. Then, one end of the developing roller shaft 32 in the first direction is rotatably supported with respect to the rotation shaft A1 extending in the first direction. Further, the first bearing 60 is also rotatable with respect to the casing 10 with respect to the developing roller shaft 32. Specifically, the second end portion 62 can rotate with respect to the rotation shaft A1 with respect to the first end portion 61.

The first bearing 60 is a conductive developing electrode. The first bearing 60 is made of, for example, a conductive resin. However, the first bearing 60 may be made of metal. The first end 61 of the first bearing 60 comes into contact with one end of the developing roller shaft 32 in the first direction. Therefore, the first end 61 of the first bearing 60 is electrically connected to the developing roller shaft 32.

Further, the first bearing 60 has a first hole 67. The first hole 67 extends in the second direction between the first end 61 and the second end 62. Further, the first hole 67 penetrates the first bearing 60 in the rotation direction about the rotation shaft A1. However, the first hole 67 does not have to penetrate the first bearing 60. The other end 112 of the first lever 110, which will be described later, is inserted into the first hole 67.

The first lever 110 is located on the first outer surface 11 of the casing 10. As shown in FIG. 4, the first lever 110 has one end 111, the other end 112, and a cam surface 113. The one end 111 is located at one end of the first lever 110 in the third direction intersecting the first and second directions. The other end 112 is located at the other end of the first lever 110 in the third direction. The cam surface 113 is located between one end 111 and the other 112 in the third direction. Further, one end 111 of the first lever 110 has a first convex portion 114. The first convex portion 114 projects in the first direction from one end portion 111 of the first lever 110. The other end 112 of the first lever 110 has a second convex portion 115. The second convex portion 115 projects in the first direction from the other end 112 of the first lever 110.

The first lever 110 is movable with respect to the casing 10. With the developing cartridge 1 mounted on the drum cartridge 2, the cam surface 113 can come into contact with the drum frame 91, which will be described later, of the drum cartridge 2. Then, the first lever 110 can rotate between the first position and the second position about the cam surface 113.

The other end 112 of the first lever 110 is inserted into the first hole 67 of the first bearing 60. The other end 112 of the first lever 110 is connected to the inner surface of the first hole 67 of the first bearing 60. Specifically, the first bearing 60 has an engaging surface 69 (see FIG. 11) on the inner surface of the first hole 67. Then, the engaging surface 69 and the second convex portion 115 of the first lever 110 face each other in the third direction. That is, the second convex portion 115 of the first lever 110 engages with the engaging surface 69 of the first bearing 60. As a result, the first lever 110 from the first bearing 60 is prevented from coming off to one side in the third direction. Further, the rotation range of the first bearing 60 centered on the rotation shaft A1 is regulated.

The holder 120 is located on the first outer surface 11 of the casing 10. The holder 120 is fixed to the first outer surface 11 of the casing 10, for example, by screwing. A part of the first lever 110 is located between the first outer surface 11 and the holder 120. The first convex portion 114 of the first lever 110 is located on one side of the holder 120 in the third direction. The second convex portion 115 of the first lever 110 is located on the other side of the holder 120 in the third direction. The first convex portion 114 and the holder 120 face each other in the third direction. This prevents the first lever 110 from coming off from the holder 120 to the other side in the third direction. That is, the holder 120 holds the first lever 110 so as to be movable with respect to the casing 10.

The second bearing 70 is located on the second outer surface 12 of the casing 10. More specifically, the second bearing 70 is located on the outer surface of the gear cover 53. The first bearing 60 and the second bearing 70 are positioned so as to overlap each other in the first direction. The second bearing 70 rotatably supports the other end of the developing roller shaft 32 in the first direction. As shown in FIG. 5, the second bearing 70 has a third end portion 71 and a fourth end portion 72. The fourth end 72 is farther from the developing roller shaft 32 than the third end 71. Further, the fourth end portion 72 is separated from the third end portion 71 in the second direction from one end of the casing 10 in the second direction. The second bearing 70 extends between the third end 71 and the fourth end 72 along the second outer surface 12 of the casing 10.

The second bearing 70 has a third arm 73 and a fourth arm 74. The fourth arm 74 is farther from the developing roller shaft 32 than the third arm 73. Further, the fourth arm 74 is separated from the third arm 73 in the second direction from one end of the casing 10 in the second direction. The third arm 73 has the third end 71 described above. The fourth arm 74 has the fourth end 72 described above. The third arm 73 extends, for example, linearly along the second outer surface 12 of the casing 10. The fourth arm 74 extends, for example, linearly along the second outer surface 12 of the casing 10. However, the third arm 73 is bent with respect to the fourth arm 74. The angle formed by the third arm 73 and the fourth arm 74 is an obtuse angle.

In the present embodiment, the third arm 73 and the fourth arm 74 are integrally molded. However, the third arm 73 and the fourth arm 74 may be separate parts. In that case, the third arm 73 and the fourth arm 74 may be fixed to each other.

The second bearing 70 has a second insertion hole 75. The second insertion hole 75 extends in the first direction at the third end 71 of the second bearing 70. The second insertion hole 75 may be a through hole that penetrates the third end portion 71 in the first direction, or may not penetrate the third end portion 71. The second insertion hole 75 has a cylindrical inner peripheral surface. The other end of the developing roller shaft 32 in the first direction is inserted into the second insertion hole 75. As a result, the second bearing 70 is mounted on the other end of the developing roller shaft 32 in the first direction. Then, the other end of the developing roller shaft 32 in the first direction is rotatably supported with respect to the rotation shaft A1 extending in the first direction. Further, the second bearing 70 is also rotatable with respect to the casing 10 with respect to the developing roller shaft 32. Specifically, the fourth end portion 72 is rotatable with respect to the third end portion 71 with respect to the rotation shaft A1.

Further, the second bearing 70 has a third hole 77. The third hole 77 extends in the second direction between the third end 71 and the fourth end 72. Further, the third hole 77 penetrates the second bearing 70 in the rotation direction about the rotation shaft A1. However, the third hole 77 does not have to penetrate the second bearing 70. The other end 132 of the second lever 130, which will be described later, is inserted into the third hole 77. The first hole 67 of the first bearing 60 and the third hole 77 of the second bearing 70 are positioned so as to overlap each other in the first direction.

The second lever 130 is located on the second outer surface 12 of the casing 10. More specifically, the second bearing 70 is located on the outer surface of the gear cover 53. As shown in FIG. 5, the second lever 130 has one end 131, the other end 132, and a cam surface 133. The one end 131 is located at one end of the second lever 130 in the third direction. The other end 132 is located at the other end of the second lever 130 in the third direction. The cam surface 133 is located between one end 131 and the other 132 in the third direction. Further, the other end 132 of the second lever 130 has a third convex portion 135. The third convex portion 135 projects in the first direction from the other end 132 of the second lever 130.

One end 111 of the first lever 110 and 131 one end of the second lever 130 are positioned so as to overlap each other in the first direction. The other end 112 of the first lever 110 and the other end 132 of the second lever 130 are positioned so as to overlap each other in the first direction.

The second lever 130 is movable with respect to the casing 10. With the developing cartridge 1 mounted on the drum cartridge 2, the cam surface 133 can come into contact with the drum frame 91, which will be described later, of the drum cartridge 2. Then, the second lever 130 is rotatable between the third position and the fourth position with respect to the cam surface 133.

The other end 132 of the second lever 130 is inserted into the third hole 77 of the second bearing 70. The other end 132 of the second lever 130 is connected to the inner surface of the third hole 77 of the second bearing 70. Specifically, the second bearing 70 has an engaging surface (not shown) on the inner surface of the third hole 77. Then, the engaging surface and the third convex portion 135 of the second lever 130 face each other in the third direction. That is, the third convex portion 135 of the second lever 130 engages with the engaging surface of the second bearing 70. This prevents the second lever 130 from coming off from the second bearing 70 to one side in the third direction. Further, the rotation range of the second bearing 70 centered on the rotation shaft A1 is regulated.

As shown in FIG. 5, the gear cover 53 has a gear cover convex portion 532 projecting in the first direction. The second lever 130 is located between the collar 531 of the gear cover 53 and the convex portion 532 of the gear cover in the second direction. As a result, the movement of the second lever 130 in the second direction is restricted. Further, the second lever 130 extends in an arc shape along the outer peripheral surface of the collar 531 of the gear cover 53. A portion of the collar 531 is located between one end 131 and the other end 132 of the second lever 130 in the third direction. As a result, the movement of the second lever 130 in the third direction is restricted.

<1-3. Drum cartridge structure>
As shown in FIG. 1, the drum cartridge 2 includes a drum frame 91 and a photoconductor drum 92. The developing cartridge 1 is mounted on the drum frame 91. The photoconductor drum 92 is a cylindrical drum that can rotate about a rotation axis extending in the first direction. The outer peripheral surface of the photoconductor drum 92 is coated with a photosensitive material. The photoconductor drum 92 is located at one end of the drum frame 91 in the second direction. When the developing cartridge 1 is mounted on the drum frame 91, the outer peripheral surface of the developing roller 30 comes into contact with the outer peripheral surface of the photoconductor drum 92.

6 to 8 are views of the development cartridge 1 mounted on the drum cartridge 2 as viewed from one side in the first direction. FIG. 9 is a cross-sectional view of the developing cartridge 1 and the drum cartridge 2 in a state where the developing cartridge 1 is mounted on the drum cartridge 2. Note that FIG. 9 shows a cross section orthogonal to the first direction and passing through the first bearing 60 and the first lever 110.

As shown in FIG. 9, the drum cartridge 2 has a first guide surface 93 and a second guide surface 94. The first guide surface 93 and the second guide surface 94 are located at one end of the drum frame 91 in the first direction. Further, the first guide surface 93 and the second guide surface 94 are separated from each other in the rotation direction about the rotation axis of the photoconductor drum 92. The drum cartridge 2 also has a third guide surface (not shown) and a fourth guide surface (not shown) similar to the first guide surface 93 and the second guide surface 94 on the other end of the drum frame 91 in the first direction. Omitted).

Further, as shown in FIG. 9, the drum cartridge 2 includes a first pressing member 95 and a first coil spring 96. The first pressing member 95 and the first coil spring 96 are conductive. The first pressing member 95 is made of, for example, a conductive resin. The first coil spring 96 is made of, for example, metal. The first pressing member 95 and the first coil spring 96 are located at one end of the drum frame 91 in the first direction. The first coil spring 96 is an elastic member that can expand and contract in the second direction. One end of the first coil spring 96 in the second direction is connected to the first pressing member 95. The other end of the first coil spring 96 in the second direction is connected to the drum frame 91. When the developing cartridge 1 is mounted on the drum cartridge 2, the first pressing member 95 presses the second end portion 62 of the first bearing 60 toward the photoconductor drum 92 by the elastic force of the first coil spring 96. do.

Further, the drum cartridge 2 includes a second pressing member (not shown) and a second coil spring (not shown). The second pressing member and the second coil spring are located at the other end of the drum frame 91 in the first direction. When the developing cartridge 1 is mounted on the drum cartridge 2, the second pressing member presses the fourth end 72 of the second bearing 70 toward the photoconductor drum 92 by the elastic force of the second coil spring.

The drum cartridge 2 may include other types of elastic members instead of the first coil spring 96 and the second coil spring. For example, the drum cartridge 2 may include a spring other than a coil spring such as a torsion spring or a leaf spring, rubber, or the like as an elastic member.

Further, as shown in FIGS. 6 to 9, the drum cartridge 2 includes a first release lever 97. The first release lever 97 is located at one end of the drum frame 91 in the first direction. The first release lever 97 is rotatable about a shaft extending in the first direction. Further, the drum cartridge 2 includes a second release lever (not shown). The second release lever is located at the other end of the drum frame 91 in the first direction. The second release lever is rotatable about a rotation axis extending in the first direction.

<1-4. About the mounting operation of the developing cartridge>
When the developing cartridge 1 is mounted on the drum cartridge 2, the developing cartridge 1 moves with respect to the drum cartridge 2 so that the developing roller 30 approaches the photoconductor drum 92, as shown in FIGS. 6 to 9. At this time, as shown in FIGS. 6 to 9, the second end portion 62 of the first bearing 60 comes into contact with the first release lever 97 and moves along the first release lever 97. Along with this, the first bearing 60 rotates about the rotation shaft A1. Similarly, the third end 71 of the second bearing 70 comes into contact with the second release lever and moves along the second release lever. Along with this, the second bearing 70 rotates about the rotation shaft A1.

In this way, when the developing cartridge 1 is mounted on the drum cartridge 2, the first bearing 60 and the second bearing 70 rotate about the rotating shaft A1 of the developing roller 30. Therefore, the first bearing 60 is arranged between the photoconductor drum 92 and the first pressing member 95 without rotating the casing 10 with respect to the drum frame 91, and the second bearing 70 is placed on the photoconductor drum. It can be arranged between the 92 and the second pressing member. Therefore, the user of the image forming apparatus can bring the developing roller 30 closer to the photoconductor drum 92 without rotating the casing 10.

When the first bearing 60 is arranged between the photoconductor drum 92 and the first pressing member 95, the first pressing member 95 comes into contact with the second end portion 62 of the first bearing 60. Then, the elastic force of the first coil spring 96 causes the first pressing member 95 to press the second end portion 62 of the first bearing 60 toward the photoconductor drum 92. Then, as shown in FIG. 9, the first end portion 61 of the first bearing 60 comes into contact with the first guide surface 93, and the other portion of the first bearing 60 comes into contact with the second guide surface 94. As a result, the position of the first bearing 60 with respect to the drum frame 91 is fixed.

Similarly, the second pressing member presses the fourth end 72 of the second bearing 70 toward the photoconductor drum 92. Then, the third end portion 71 of the second bearing 70 comes into contact with the third guide surface, and the other portion of the second bearing 70 comes into contact with the fourth guide surface. As a result, the position of the second bearing 70 with respect to the drum frame 91 is fixed.

Further, with the positions of the first bearing 60 and the second bearing 70 fixed with respect to the drum frame 91, the first pressing member 95 presses the first bearing 60, and the second pressing member presses the second bearing 70. .. As a result, the outer peripheral surface of the developing roller 30 comes into contact with the outer peripheral surface of the photoconductor drum 92. Then, the developing roller 30 is pressed against the photoconductor drum 92.

As described above, in the present embodiment, the first bearing 60 has the first end portion 61 and the second end portion 62, and the second end portion 62 is rotatable with respect to the first end portion 61. Is. Further, the second bearing 70 has a third end portion 71 and a fourth end portion 72, and the fourth end portion 72 is rotatable with respect to the third end portion 71. Therefore, the first end portion 61 and the second end portion 62 of the first bearing 60 and the third end portion 71 and the fourth end portion 72 of the second bearing 70 are used with respect to the photoconductor drum 92. The developing roller 30 can be positioned.

Further, in the present embodiment, when the developing cartridge 1 is mounted on the drum cartridge 2, the first bearing 60 and the second bearing 70 rotate about the rotation shaft A1. also. Similarly, when the developing cartridge 1 is removed from the drum cartridge 2, the first bearing 60 and the second bearing 70 rotate about the rotation shaft A1. Therefore, the first bearing 60 and the second bearing 70 can be rotated without rotating the casing 10, and the operation of attaching and detaching the developing cartridge 1 to the drum cartridge 2 can be smoothly performed.

<1-5. About voltage supply>
The first pressing member 95 and the first coil spring 96 are conductive. The first pressing member 95 is made of, for example, a conductive resin. The first coil spring 96 is made of, for example, metal. Further, the drum cartridge 2 includes an electrode terminal 98 that makes electrical contact with the first coil spring 96. As shown in FIGS. 6 to 8, the electrode terminals 98 are exposed on the outer surface of the drum frame 91. Further, as described above, the developing roller shaft 32 and the first bearing 60 are also conductive. Therefore, when the developing cartridge 1 is mounted on the drum cartridge 2 and the first pressing member 95 comes into contact with the first bearing 60, the electrode terminal 98, the first coil spring 96, the first pressing member 95, and the first bearing 60 , And the developing roller shaft 32 are electrically conductive with each other.

When the developing cartridge 1 mounted on the drum cartridge 2 is mounted on the image forming apparatus, the electrode terminal of the image forming apparatus and the electrode terminal 98 of the drum cartridge 2 come into contact with each other. Then, a bias voltage is supplied from the image forming apparatus to the developing roller shaft 32 via the electrode terminal 98, the first coil spring 96, the first pressing member 95, and the first bearing 60. As a result, the developer is attracted to the outer peripheral surface of the developing roller main body 31 by the electrostatic force due to the bias voltage.

As described above, in the present embodiment, the bias voltage is supplied to the first bearing 60 of the developing cartridge 1 via the first pressing member 95 of the drum cartridge 2. In this way, the number of parts of the drum cartridge 2 can be reduced as compared with the case where a conductive part for supplying a voltage to the first bearing 60 is provided separately from the first pressing member 95. Therefore, the drum cartridge 2 can be miniaturized.

Further, the first bearing 60 of the present embodiment has (1) a function as a bearing that rotatably supports the developing roller shaft 32, and (2) a photoconductor drum 92 when the developing cartridge 1 is mounted on the drum cartridge 2. It functions as a positioning member for positioning the developing roller 30 and (3) as a developing electrode for supplying a bias voltage to the developing roller shaft 32. Therefore, as compared with the case where these functions are realized by separate members, the number of parts of the developing cartridge 1 can be reduced and the developing cartridge 1 can be miniaturized.

<1-6. Separation operation>
After the developing cartridge 1 is mounted on the image forming apparatus while being mounted on the drum cartridge 2, the developing cartridge 1 can be separated by the driving force supplied from the image forming apparatus. The separation operation is an operation of temporarily separating the developing roller 30 from the photoconductor drum 92. For example, when monochrome printing is performed in the image forming apparatus, the developing cartridges 1 of each color other than black perform a separation operation. However, the black developing cartridge 1 may perform a separating operation.

As shown in FIG. 9, when the developing cartridge 1 is mounted on the drum cartridge 2, the developing cartridge 1 is arranged at a contact position where the developing roller 30 comes into contact with the photoconductor drum 92. The position of the first lever 110 at this time is the first position. At the first position, the other end 112 of the first lever 110 is separated from the inner surface 670 of the first hole 67 of the first bearing 60. Therefore, the other end 112 of the first lever 110 does not press the inner surface 670 of the first hole 67. Further, the cam surface 113 of the first lever 110 is in contact with the drum frame 91. The position of the second lever 130 at this time is the third position. At the third position, the other end 132 of the second lever 130 is separated from the inner surface of the third hole 77 of the second bearing 70. Therefore, the other end 132 of the second lever 130 does not press the inner surface of the third hole 77 of the second bearing 70. Further, the cam surface 133 of the second lever 130 is in contact with the drum frame 91.

FIG. 10 is a cross-sectional view of the developing cartridge 1 and the drum cartridge 2 during the separation operation. Note that FIG. 10 shows a cross section orthogonal to the first direction and passing through the first bearing 60 and the first lever 110.

The image forming apparatus applies a driving force to one end 111 of the first lever 110 when performing the separation operation. Specifically, the image forming apparatus operates a drive lever (not shown). Then, the drive lever presses one end 111 of the first lever 110 as shown by the broken line arrow in FIG. As a result, the first lever 110 rotates from the first position to the second position around the cam surface 113. At this time, the other end 112 of the first lever 110 moves away from the photoconductor drum 92 and presses the inner surface 670 of the first hole 67 of the first bearing 60. Specifically, the other end 112 of the first lever 110 presses the second end 62 of the first bearing 60 in a direction away from the developing roller 30 against the pressing force of the first pressing member 95. As a result, the first bearing 60 moves away from the photoconductor drum 92 together with the other end 112 of the first lever 110.

Further, the image forming apparatus applies a driving force to one end 131 of the second lever 130 when performing the separation operation. Specifically, the image forming apparatus operates another drive lever (not shown). Then, the drive lever presses one end 131 of the second lever 130. As a result, the second lever 130 rotates from the third position to the fourth position around the cam surface 133. At this time, the other end 132 of the second lever 130 moves away from the photoconductor drum 92 and presses the inner surface of the third hole 77 of the second bearing 70. Specifically, the other end 132 of the second lever 130 presses the fourth end 72 of the second bearing 70 in a direction away from the developing roller 30 against the pressing force of the second pressing member. As a result, the second bearing 70 moves away from the photoconductor drum 92 together with the other end 132 of the second lever 130.

As a result, the casing 10 and the developing roller 30 move in the direction away from the photoconductor drum 92 together with the first bearing 60 and the second bearing 70. As a result, the outer peripheral surface of the developing roller 30 is separated from the outer peripheral surface of the photoconductor drum 92. That is, the developing cartridge 1 moves from the above-mentioned contact position to the separated position with respect to the drum cartridge 2.

As described above, in the present embodiment, the other end 112 of the first lever 110 is the first bearing 60 according to the force received by the one end 111 of the first lever 110 from the drive lever of the image forming apparatus. The inner surface 670 of the hole 67 is pressed. As a result, a force for moving the developing cartridge 1 from the contact position to the separated position can be applied. That is, the driving force supplied from the image forming apparatus by the first lever 110 having one end 111 that functions as a force point, the other end 112 that functions as an action point, and a cam surface 113 that functions as a fulcrum. It can be transmitted to the first bearing 60.

Further, the other end 132 of the second lever 130 presses the inner surface of the third hole 77 of the second bearing 70 according to the force received by the one end 131 of the second lever 130 from the drive lever of the image forming apparatus. .. As a result, a force for moving the developing cartridge 1 from the contact position to the separated position can be applied. That is, the driving force supplied from the image forming apparatus by the second lever 130 having one end 131 that functions as a force point, the other end 132 that functions as an action point, and a cam surface 133 that functions as a fulcrum. It can be transmitted to the second bearing 70.

That is, the driving force supplied from the image forming apparatus is transmitted to the first bearing 60 and the second bearing 70 of the developing cartridge 1 without going through the drum cartridge 2. In this way, it is not necessary to provide the drum cartridge 2 with a component that relays the driving force. Therefore, the number of parts of the drum cartridge 2 can be reduced. Therefore, the drum cartridge 2 can be miniaturized.

Further, in the developing cartridge 1, one end portion 111 of the first lever 110 has a first convex portion 114 protruding in the first direction. Therefore, the surface area of one end 111 of the first lever 110 is larger than that without the first convex 114. Therefore, the drive lever of the image forming apparatus can stably press one end 111 of the first lever 110 during the separation operation. As a result, the separation operation of the image forming apparatus is stabilized. Similar to the first lever 110, the one end 131 of the second lever 130 may also have a convex portion protruding in the first direction.

Further, in the developing cartridge 1, the first bearing 60 and the second bearing 70 that support the developing roller shaft 32 receive pressing force during the separating operation. Therefore, the number of parts of the developing cartridge 1 can be reduced as compared with the case where a member that receives a pressing force during the separation operation is provided separately from the first bearing 60 and the second bearing 70. Therefore, the developing cartridge 1 can be miniaturized.

Further, the first bearing 60 is rotatable about the rotation shaft A1. Therefore, the first lever 110 can press the inner surface 670 of the first hole 67 of the first bearing 60 in the optimum direction. Similarly, the second bearing 70 is also rotatable about the rotation shaft A1. Therefore, the second lever 130 can press the inner surface of the third hole 77 of the second bearing 70 in the optimum direction.

Further, when the developing cartridge 1 moves from the contact position to the separated position, the first bearing 60 moves along the second guide surface 94. Further, the second bearing 70 moves along the fourth guide surface. As a result, the first lever 110 can press the first bearing 60 while maintaining the position of the first bearing 60 about the rotation shaft A1. Further, the second lever 130 can press the second bearing 70 while maintaining the position of the second bearing 70 about the rotation shaft A1.

<1-7. About the removal operation of the developing cartridge>
FIG. 11 is a cross-sectional view of the developing cartridge 1 and the drum cartridge 2 when the developing cartridge 1 is removed from the drum cartridge 2. Note that FIG. 11 shows a cross section orthogonal to the first direction and passing through the first bearing 60 and the first lever 110.

When removing the developing cartridge 1 from the drum cartridge 2, the user presses the first release lever 97 and the second release lever. As a result, the first release lever 97 and the second release lever rotate about the shaft extending in the first direction. Then, the first release lever 97 presses the first lever 110 to one side in the third direction. Further, the second release lever presses the second lever 130 to one side in the third direction. Further, the other end 112 of the first lever 110 comes into contact with the engaging surface 69 of the first bearing 60 and presses the engaging surface 69 toward one side in the third direction. Further, the other end 132 of the second lever 130 comes into contact with the engaging surface of the second bearing 70 and presses the engaging surface 79 toward one side in the third direction.

As a result, the first bearing 60 is pulled out from between the photoconductor drum 92 and the first pressing member 95 toward one side in the third direction. Further, the second bearing 70 is pulled out from between the photoconductor drum 92 and the second pressing member toward one side in the third direction. As a result, the developing cartridge 1 can be removed from the drum cartridge 2.

<2. Second Embodiment>
<2-1. Overview of developing cartridges and drum cartridges>
12 to 14 are perspective views of the developing cartridge 1B and the drum cartridge 2B. FIG. 12 shows a state in which the developing cartridge 1B is mounted on the drum cartridge 2B. 13 and 14 show a state in which the developing cartridge 1B is not mounted on the drum cartridge 2B. The developing cartridge 1B and the drum cartridge 2B are used in an electrophotographic image forming apparatus. The image forming apparatus is, for example, a laser printer or an LED printer.

As shown in FIGS. 12 to 14, the developing cartridge 1B is used together with the drum cartridge 2B. The developing cartridge 1B can be attached to the drum cartridge 2B. The developing cartridge 1B is mounted on the image forming apparatus in a state of being mounted on the drum cartridge 2B. The image forming apparatus can be equipped with, for example, four developing cartridges 1B. The four developing cartridges 1B contain developing agents (eg, toner) of different colors (eg, cyan, magenta, yellow, and black). The image forming apparatus forms an image on the recording surface of the printing paper by the developing agent supplied from the developing cartridge 1B. However, the number of developing cartridges 1B that can be attached to the image forming apparatus may be 1 to 3 or 5 or more.

<2-2. Development cartridge structure>
FIG. 15 is a perspective view of the developing cartridge 1B in the vicinity of the first outer surface 11B of the casing 10B. FIG. 16 is an exploded perspective view of the developing cartridge 1B in the vicinity of the first outer surface 11B of the casing 10B. FIG. 17 is a perspective view of the developing cartridge 1B in the vicinity of the second outer surface 12B of the casing 10B. FIG. 18 is an exploded perspective view of the developing cartridge 1B in the vicinity of the second outer surface 12B of the casing 10B.

As shown in FIGS. 12 to 18, the developing cartridge 1B includes a casing 10B, an agitator 20B, a developing roller 30B, a gear portion 50B, a first bearing 60B, a first lever 110B, a holder 120B, and a second bearing 70B.

Casing 10B is a casing capable of accommodating the developer. The casing 10B has a first outer surface 11B and a second outer surface 12B. The first outer surface 11B is located at one end of the casing 10B in the first direction. The second outer surface 12B is located at the other end of the casing 10B in the first direction. The first outer surface 11B and the second outer surface 12B are separated from each other in the first direction. The casing 10B extends in the first direction between the first outer surface 11B and the second outer surface 12B, and also extends in the second direction.

A storage chamber 13B is provided inside the casing 10B. The developer is housed in the storage chamber 13B. Further, the casing 10B has an opening 14B. The opening 14B is located at one end of the casing 10B in the second direction. The external space of the casing 10B and the accommodation chamber 13B communicate with each other through the opening 14B. The casing 10B may have a handle on the outer surface of the other end in the second direction.

The agitator 20B has an agitator shaft 21B and blades 22B. The agitator shaft 21B extends along the first direction. The blades 22B extend from the agitator shaft 21B toward the inner surface of the casing 10B. A part of the agitator shaft 21B and the blades 22B are arranged in the accommodation chamber 13B of the casing 10B. An agitator gear (not shown) included in the gear portion 50B is attached to the end portion of the agitator shaft 21B in the first direction. The agitator shaft 21B is fixed to the agitator gear so as not to rotate relative to the agitator gear. When the agitator gear rotates, the agitator shaft 21B and the blades 22B rotate about a rotation shaft extending in the first direction. Then, the developer in the accommodating chamber 13B is agitated by the rotation of the blade 22B.

The developing roller 30B is a roller that can rotate about the rotation axis A1 extending in the first direction. The developing roller 30B is located in the opening 14B of the casing 10B. That is, the developing roller 30B is located at one end of the casing 10B in the second direction. The developing roller 30B includes a developing roller main body 31B and a developing roller shaft 32B. The developing roller body 31B is a cylindrical member extending in the first direction. As the material of the developing roller body 31B, for example, elastic rubber is used. The developing roller shaft 32B is a columnar member that penetrates the developing roller body 31B and extends in the first direction. The developing roller shaft 32B is conductive. As the material of the developing roller shaft 32B, a metal or a resin having conductivity is used.

The developing roller body 31B is fixed to the developing roller shaft 32B so as not to rotate relative to the developing roller shaft 32B. Further, the developing roller gear 51B included in the gear portion 50B is attached to the end portion of the developing roller shaft 32B in the first direction. The developing roller shaft 32B is fixed to the developing roller gear 51B so as not to rotate relative to the developing roller gear 51B. Therefore, when the developing roller gear 51B rotates, the developing roller shaft 32B also rotates, and the developing roller main body 31B rotates together with the developing roller shaft 32B.

The developing roller shaft 32B does not have to penetrate the developing roller main body 31B in the first direction. For example, the developing roller shaft 32B may extend in the first direction from both ends of the developing roller main body 31B in the first direction.

Further, the developing cartridge 1 has a supply roller (not shown). The supply roller is a roller that is rotatable about a rotation axis extending in the first direction. The supply roller is located between the agitator 20B and the developing roller 30B. The supply roller has a supply roller main body and a supply roller shaft. The supply roller body is a cylindrical member extending in the first direction. As the material of the supply roller body, for example, elastic rubber is used. The supply roller shaft is a columnar member that penetrates the supply roller body and extends in the first direction.

The supply roller body is fixed so as not to rotate relative to the supply roller shaft. Further, a supply roller gear (not shown) included in the gear portion 50 is attached to the end portion of the supply roller shaft in the first direction. The supply roller shaft is fixed so that it cannot rotate relative to the supply roller gear. Therefore, when the supply roller gear rotates, the supply roller shaft also rotates, and the supply roller body rotates together with the supply roller shaft.

The supply roller shaft does not have to penetrate the supply roller body in the first direction. For example, the supply roller shaft may extend in the first direction from both ends of the supply roller body in the first direction.

When the developing cartridge 1B receives the driving force, the developing agent is supplied from the accommodation chamber 13B in the casing 10B to the outer peripheral surface of the developing roller 30B via the supply roller. At that time, the developer is triboelectrically charged between the supply roller and the developing roller 30B. On the other hand, a bias voltage is applied to the developing roller shaft 32B of the developing roller 30B. Therefore, the developer is attracted to the outer peripheral surface of the developing roller body 31B by the electrostatic force between the developing roller shaft 32B and the developing agent.

Further, the developing cartridge 1B has a layer thickness regulating blade (not shown). The layer thickness regulating blade forms the developer supplied to the outer peripheral surface of the developing roller main body 31B to a constant thickness. After that, the developer on the outer peripheral surface of the developing roller main body 31B is supplied to the photoconductor drum 92B described later of the drum cartridge 2B. At this time, the developer moves from the developing roller main body 31B to the photoconductor drum 92B according to the electrostatic latent image formed on the outer peripheral surface of the photoconductor drum 92B. As a result, the electrostatic latent image is visualized on the outer peripheral surface of the photoconductor drum 92B.

The gear portion 50B is located on the second outer surface 12B of the casing 10B. As shown in FIG. 5, the gear portion 50B includes the above-mentioned agitator gear, developing roller gear 51B, supply roller gear, a plurality of idle gears, a coupling 52B, and a gear cover 53B. The gear cover 53B, together with the casing 10B, constitutes the housing of the developing cartridge 1B. The gear cover 53B is fixed to the second outer surface 12B of the casing 10B, for example, by screwing. At least a portion of the plurality of gears is located between the second outer surface 12B and the gear cover 53B.

The gear cover 53B has a cylindrical collar 531B that projects in the first direction. The coupling 52B is housed inside the collar 531B. The coupling 52B has an engaging portion 521B that is recessed in the first direction. The engaging portion 521B is exposed from the gear cover 53B. When the developing cartridge 1B mounted on the drum cartridge 2B is mounted on the image forming apparatus, the drive shaft of the image forming apparatus is connected to the engaging portion 521B of the coupling 52B. Then, the rotation of the drive shaft is transmitted to the agitator gear, the plurality of idle gears, the developing roller gear 51B, and the supply roller gear via the coupling 52B.

The plurality of gears included in the gear portion 50B may transmit the rotational force by the meshing of the teeth, or may transmit the rotational force by friction.

The first bearing 60B is located on the first outer surface 11B of the casing 10B. The first bearing 60B rotatably supports one end of the developing roller shaft 32B in the first direction. As shown in FIGS. 15 and 16, the first bearing 60B has a first end 61B and a second end 62B. The second end 62B is farther from the developing roller shaft 32B than the first end 61B. Further, the second end portion 62B is separated from the first end portion 61B in the second direction from one end of the casing 10B in the second direction. The first bearing 60B extends between the first end 61B and the second end 62B along the first outer surface 11B of the casing 10B.

The first bearing 60B has a first arm 63B and a second arm 64B. The second arm 64B is farther from the developing roller shaft 32B than the first arm 63B. Further, the second arm 64B is separated from the first arm 63B in the second direction from one end of the casing 10B in the second direction. The first arm 63B has the first end portion 61B described above. The second arm 64B has the second end 62B described above. The first arm 63B extends, for example, linearly along the first outer surface 11B of the casing 10B. The second arm 64B extends, for example, linearly along the first outer surface 11B of the casing 10B. However, the first arm 63B is bent with respect to the second arm 64B. The angle formed by the first arm 63B and the second arm 64B is an obtuse angle.

In the present embodiment, the first arm 63B and the second arm 64B are integrally molded. However, the first arm 63B and the second arm 64B may be separate parts. In that case, the first arm 63B and the second arm 64B need only be fixed to each other.

The first bearing 60B has a first insertion hole 65B. The first insertion hole 65B extends in the first direction at the first end 61B of the first bearing 60B. The first insertion hole 65B may be a through hole that penetrates the first end portion 61B in the first direction, or may not penetrate the first end portion 61B. One end of the developing roller shaft 32B in the first direction is inserted into the first insertion hole 65B. As a result, the first bearing 60B is mounted on one end of the developing roller shaft 32B in the first direction. Then, one end of the developing roller shaft 32B in the first direction is rotatably supported with respect to the rotation shaft A1 extending in the first direction. Further, the first bearing 60B is also rotatable with respect to the casing 10B with respect to the developing roller shaft 32B. Specifically, the second end portion 62B is rotatable with respect to the rotation shaft A1 with respect to the first end portion 61B.

The first bearing 60B is a conductive developing electrode. The first bearing 60B is made of, for example, a conductive resin. However, the first bearing 60B may be made of metal. The first end 61B of the first bearing 60B comes into contact with one end of the developing roller shaft 32B in the first direction. Therefore, the first end 61B of the first bearing 60B is electrically connected to the developing roller shaft 32B.

Further, the first bearing 60B has a first hole 67B. The first hole 67B is located between the first end 61B and the second end 62B. Further, the first hole 67B penetrates the first bearing 60B in the rotation direction about the rotation shaft A1. That is, the first hole 67B extends in a third direction intersecting the first and second directions. However, the first hole 67B does not have to penetrate the first bearing 60B. The other end 112B of the first lever 110B, which will be described later, is inserted into the first hole 67B.

The first lever 110B is located on the first outer surface 11B of the casing 10B. As shown in FIG. 16, the first lever 110B has one end 111B, the other end 112B, and a cam surface 113B. The one end 111B is located at one end of the first lever 110B in the third direction intersecting the first and second directions. The other end 112B is located at the other end of the first lever 110B in the third direction. That is, the other end 112B is separated from the one end 111B toward the other side in the third direction. The cam surface 113B is located between one end 111B and the other end 112B in the third direction. Further, one end portion 111B of the first lever 110B has a first convex portion 114B. The first convex portion 114B projects in the first direction from one end portion 111B of the first lever 110B. The other end 112B of the first lever 110B has a second convex portion 115B. The second convex portion 115B projects in the first direction from the other end portion 112B of the first lever 110B.

The first lever 110B is movable with respect to the casing 10B. With the developing cartridge 1B mounted on the drum cartridge 2B, the cam surface 113B can come into contact with the drum frame 91B described later of the drum cartridge 2B. The first lever 110B can rotate between the first position and the second position about the cam surface 113B.

The holder 120B is located on the first outer surface 11B of the casing 10B. The holder 120B is fixed to the first outer surface 11B of the casing 10B, for example, by screwing. A part of the first lever 110B is located between the first outer surface 11B and the holder 120B. The first convex portion 114B of the first lever 110B is located on one side of the holder 120B in the third direction. The second convex portion 115B of the first lever 110B is located on the other side of the holder 120B in the third direction. The first convex portion 114B and the holder 120B face each other in the third direction. As a result, the holder 120B and the first lever 110B are prevented from coming out from one side to the other side in the third direction. That is, the holder 120B movably holds the first lever 110B with respect to the casing 10B.

FIG. 19 is a view showing a cross section of the first bearing 60B and a side surface of the first lever 110B. As shown by the broken line arrow in FIG. 19, the other end 112B of the first lever 110B is inserted into the first hole 67B of the first bearing 60B. Further, the first bearing 60B has a lever receiving portion 68B. The lever receiving portion 68B is located inside the first hole 67B. The lever receiving portion 68B has a U shape that opens toward the other side in the third direction. The second convex portion 115B of the first lever 110B is inserted into the lever receiving portion 68B. As a result, the other end 112B of the first lever 110B engages with the first bearing 60B. Further, the first lever 110B from the first bearing 60B is prevented from coming off to one side in the third direction.

As shown in FIG. 19, the first bearing 60B has an arcuate wall portion 651B at the peripheral edge of the first insertion hole 65B. The wall portion 651B projects from a part of the peripheral edge portion of the first insertion hole 65B on the other side in the second direction toward one side in the second direction. On the other hand, as shown in FIG. 16, the developing roller shaft 32B has an annular engaging groove 321B on the outer peripheral surface. The engagement groove 321B is located on one side in the first direction with respect to the first outer surface 11B of the casing 10B. The wall portion 651B projects toward the engagement groove 321B.

20 and 21 are views showing a state when the first bearing 60B, the first lever 110B, and the holder 120B are attached to the developing cartridge 1B.

When attaching the first bearing 60B, the first lever 110B, and the holder 120B to the developing cartridge 1B, first, the second convex portion 115B of the first lever 110B is inserted into the lever receiving portion 68B of the first bearing 60B. .. As a result, the other end 112B of the first lever 110B is engaged with the first bearing 60B. Next, as shown in FIG. 20, the developing roller shaft 32B is inserted into the first insertion hole 65B of the first bearing 60B. Subsequently, the first bearing 60B and the first lever 110B are rotated about the rotation shaft A1 to one side in the third direction. Then, as shown in FIG. 21, the holder 120B is fixed to the first outer surface 11B of the casing 10B. As a result, the first lever 110B is held by the holder 120B.

When the first lever 110B engaged with the first bearing 60B is held by the holder 120 in this way, the wall portion 651B of the first bearing 60B is inserted into the engaging groove 321B of the developing roller shaft 32B. This prevents the first bearing 60B from coming off from the developing roller shaft 32B to one side in the first direction.

When the first bearing 60B rotates from one side to the other side of the rotation shaft A1 in the third direction, the first lever 110B together with the lever receiving portion 68B of the first bearing 60B also moves from one side to the other in the third direction. Move to the side. However, when the first convex portion 114B of the first lever 110B comes into contact with the holder 120B, the movement of the first lever 110B from one side to the other in the third direction is stopped. When the movement of the first lever 110B is stopped, the lever receiving portion 68B of the first bearing 60B comes into contact with the second convex portion 115B of the other end 112B of the first lever 110B, so that the first bearing 60B becomes the first. The rotation from one side to the other in the three directions also stops. As a result, the rotation range of the first bearing 60B to the other side in the third direction is limited.

As described above, in the developing cartridge 1B of the present embodiment, the holder 120B stops the first lever 110B from coming off from one side to the other in the third direction. Then, the first lever 110B stops the rotation of the first bearing 60B from one side to the other in the third direction. Therefore, apart from the first lever 110B and the holder 120B, it is not necessary to provide a component for stopping the rotation of the first bearing 60B from one side to the other in the third direction. Therefore, the number of parts of the developing cartridge 1B can be reduced.

Further, as shown in FIGS. 16 and 20, the casing 10B has a casing protrusion 15B. The casing protrusion 15B extends from the first outer surface 11B of the casing 10B toward one side in the first direction. On the other hand, as shown by the broken lines in FIGS. 20 and 21, the first bearing 60B has an electrode protrusion 601B. The electrode projections 601B extend in the first direction from the first bearing 60B toward the first outer surface 11B of the casing 10.

When the first bearing 60B rotates from the other side to the one side in the third direction with respect to the rotation shaft A1, the electrode projection 601B comes into contact with the casing projection 15B. As a result, the rotation of the first bearing 60B from the other side to the one side in the third direction is stopped. As described above, in the developing cartridge 1B of the present embodiment, the casing protrusion 15B of the casing 10B stops the rotation of the first bearing 60B from the other side to the one side in the third direction. Therefore, apart from the casing 10B, it is not necessary to provide a component for stopping the rotation of the first bearing 60B from the other side to the one side in the third direction. Therefore, the number of parts of the developing cartridge 1B can be reduced.

The second bearing 70B is located on the second outer surface 12B of the casing 10B. More specifically, the second bearing 70B is located on the outer surface of the gear cover 53B. The first bearing 60B and the second bearing 70B are positioned so as to overlap each other in the first direction. The second bearing 70B rotatably supports the other end of the developing roller shaft 32B in the first direction. As shown in FIGS. 17 and 18, the second bearing 70B has a third end 71B and a fourth end 72B. The fourth end 72B is farther from the developing roller shaft 32B than the third end 71B. Further, the fourth end portion 72B is separated from the third end portion 71B in the second direction from one end of the casing 10B in the second direction. The second bearing 70B extends between the third end 71B and the fourth end 72B along the second outer surface 12B of the casing 10B.

The second bearing 70B has a third arm 73B and a fourth arm 74B. The fourth arm 74B is farther from the developing roller shaft 32B than the third arm 73B. Further, the fourth arm 74B is separated from the third arm 73B in the second direction from one end of the casing 10B in the second direction. The third arm 73B has the above-mentioned third end portion 71B. The fourth arm 74B has the fourth end 72B described above. The third arm 73B extends, for example, linearly along the second outer surface 12B of the casing 10. The fourth arm 74B extends, for example, linearly along the second outer surface 12B of the casing 10B. However, the third arm 73B is bent with respect to the fourth arm 74B. The angle formed by the third arm 73B and the fourth arm 74B is an obtuse angle.

In the present embodiment, the third arm 73B and the fourth arm 74B are integrally molded. However, the third arm 73B and the fourth arm 74B may be separate parts. In that case, the third arm 73B and the fourth arm 74B need only be fixed to each other.

FIG. 22 is a partial cross-sectional view of the developing cartridge 1B in the vicinity of the second bearing 70B. As shown in FIGS. 17, 18, and 22, the second bearing 70B has a second insertion hole 75B. The second insertion hole 75B extends in the first direction at the third end 71B of the second bearing 70B. The second insertion hole 75B may be a through hole that penetrates the third end portion 71B in the first direction, or may not penetrate the third end portion 71B. The second insertion hole 75B has a cylindrical inner peripheral surface. The other end of the developing roller shaft 32B in the first direction is inserted into the second insertion hole 75B. Then, the other end of the developing roller shaft 32B in the first direction is rotatably supported with respect to the rotation shaft A1 extending in the first direction. Further, the second bearing 70B is also rotatable with respect to the casing 10B with respect to the developing roller shaft 32B. Specifically, the fourth end 72B is rotatable with respect to the third end 71B with respect to the rotation shaft A1.

Further, the second bearing 70B has a second hole 78B. The second hole 78B extends in the first direction between the third end 71B and the fourth end 72B. Further, the second hole 78B penetrates the second bearing 70B in the first direction. However, the second hole 78B does not have to penetrate the second bearing 70B.

Further, as shown in FIG. 22, the second bearing 70B has a claw receiving portion 781B. The claw receiving portion 781B is located inside the second hole 78B. On the other hand, the casing 10B has two claws 16B. The claw portion 16B extends from the second outer surface 12B of the casing 10B toward the other side in the first direction. In this embodiment, two claws 16B extend from the outer surface of the gear cover 53B that functions as part of the casing.

The tip portion 161B of the claw portion 16B is located inside the second hole 78B. The tip portion 161B of the claw portion 16B projects in a direction intersecting the first direction and engages with the other side surface of the claw receiving portion 781B in the first direction. As a result, the second bearing 70B is held with respect to the gear cover 53B. Further, the second bearing 70B is prevented from coming off to the other side in the first direction. In this way, it is not necessary to provide an engaging groove for preventing the second bearing 70B from coming off in the portion of the developing roller shaft 32B to be inserted into the second insertion hole 75B.

When the second bearing 70B rotates from one side to the other side of the rotation shaft A1 in the third direction, the portion of the second bearing 70B on one side in the third direction from the second hole 78B becomes the claw portion 16B. Contact. As a result, the rotation of the second bearing 70B from one side to the other in the third direction is stopped. Further, when the second bearing 70B rotates from the other side in the third direction to one side with respect to the rotation shaft A1, the portion of the second bearing 70B on the other side in the third direction from the second hole 78B is a claw portion. Contact 16B. As a result, the rotation of the second bearing 70B from the other side to the one side in the third direction is stopped.

As described above, in the developing cartridge 1B of the present embodiment, the claw portion 16B stops the rotation of the second bearing 70B. Therefore, it is not necessary to provide a component for stopping the rotation of the second bearing 70B separately from the claw portion 16B. Therefore, the number of parts of the developing cartridge 1B can be reduced.

Further, as shown in FIGS. 17 and 18, the second bearing 70B has a pressed projection 701B. The pressed projection 701B projects from the other side surface of the second bearing 70B in the first direction toward the other side in the first direction. That is, the pressed projection 701B projects in a direction away from the casing 10B. The pressed projection 701B can come into contact with the separation lever 97B of the drum cartridge 2B, which will be described later, when performing the separation operation described later.

<2-3. Drum cartridge structure>
As shown in FIGS. 12 to 14, the drum cartridge 2B includes a drum frame 91B and a photoconductor drum 92B. The developing cartridge 1B is mounted on the drum frame 91B. The photoconductor drum 92B is a cylindrical drum that can rotate about a rotation axis extending in the first direction. The outer peripheral surface of the photoconductor drum 92B is coated with a photosensitive material. The photoconductor drum 92B is located at one end of the drum frame 91B in the second direction. When the developing cartridge 1B is mounted on the drum frame 91B, the outer peripheral surface of the developing roller 30B comes into contact with the outer peripheral surface of the photoconductor drum 92B.

23 and 24 are views of the development cartridge 1B mounted on the drum cartridge 2B as viewed from one side in the first direction. FIG. 25 is a view of the developed cartridge 1B and the drum cartridge 2B after mounting as viewed from one side in the first direction. FIG. 26 is a view of the developing cartridge 1B and the drum cartridge 2B at the time of the separation operation, which will be described later, as viewed from one side in the first direction. FIG. 27 is a view of the developed cartridge 1B and the drum cartridge 2B after mounting as viewed from the other side in the first direction. FIG. 28 is a view of the developing cartridge 1B and the drum cartridge 2B at the time of the separation operation, which will be described later, as viewed from the other side in the first direction.

As shown in FIGS. 23 to 25, the drum cartridge 2B has a first guide surface 93B and a second guide surface 94B. The first guide surface 93B and the second guide surface 94B are located at one end of the drum frame 91B in the first direction. Further, the first guide surface 93B and the second guide surface 94B are separated from each other in the rotation direction about the rotation axis of the photoconductor drum 92B.

Further, as shown in FIGS. 23 to 26, the drum cartridge 2B includes a first pressing member 95B and a first coil spring 96B. The first pressing member 95B and the first coil spring 96B are conductive. The first pressing member 95B is made of, for example, a conductive resin. The first coil spring 96B is made of, for example, metal. The first pressing member 95B and the first coil spring 96B are located at one end of the drum frame 91B in the first direction. The first coil spring 96B is an elastic member that can expand and contract in the second direction. One end of the first coil spring 96B in the second direction is connected to the first pressing member 95B. The other end of the first coil spring 96B in the second direction is connected to the drum frame 91B. When the developing cartridge 1B is mounted on the drum cartridge 2B, the first pressing member 95B presses the second end portion 62B of the first bearing 60B toward the photoconductor drum 92B by the elastic force of the first coil spring 96B. do.

As shown in FIGS. 27 to 28, the drum cartridge 2B has a third guide surface 931B and a fourth guide surface 941B. The third guide surface 931B and the fourth guide surface 941B are located at the other ends of the drum frame 91B in the first direction. Further, the third guide surface 931B and the fourth guide surface 941B are separated from each other in the rotation direction about the rotation axis of the photoconductor drum 92B.

Further, as shown in FIGS. 27 to 28, the drum cartridge 2B includes a second pressing member 951B and a second coil spring 961B. The second pressing member 951B and the second coil spring 961B are located at the other end of the drum frame 91B in the first direction. The second coil spring 961B is an elastic member that can expand and contract in the second direction. One end of the second coil spring 961B in the second direction is connected to the second pressing member 951B. The other end of the second coil spring 961B in the second direction is connected to the drum frame 91B. When the developing cartridge 1B is mounted on the drum cartridge 2B, the second pressing member 951B presses the fourth end 72B of the second bearing 70B toward the photoconductor drum 92B by the elastic force of the second coil spring 961B. do.

The drum cartridge 2B may include other types of elastic members in place of the first coil spring 96B and the second coil spring 961B. For example, the drum cartridge 2B may include a spring other than a coil spring such as a torsion spring or a leaf spring, rubber, or the like as an elastic member.

Further, as shown in FIGS. 27 to 28, the drum cartridge 2B includes a separation lever 97B. The separation lever 97B is located at the other end of the drum frame 91B in the first direction. The separation lever 97B is rotatable about a rotation axis extending in the first direction. Further, the separation lever 97B has a first lever arm 971B and a second lever arm 972B. When the developing cartridge 1B is mounted on the drum cartridge 2B, the second lever arm 972B faces the pressed protrusion 701B of the second bearing 70 in the second direction.

<2-4. About the mounting operation of the developing cartridge>
When the developing cartridge 1B is mounted on the drum cartridge 2B, the developing cartridge 1B moves with respect to the drum cartridge 2B so that the developing roller 30B approaches the photoconductor drum 92B as shown in FIGS. 23 to 25. At this time, the first bearing 60B rotates about the rotation shaft A1 according to the shape of the drum frame 91B. Similarly, the second bearing 70B also rotates about the rotation shaft A1 according to the shape of the drum frame 91B.

In this way, when the developing cartridge 1B is mounted on the drum cartridge 2B, the first bearing 60B and the second bearing 70B rotate about the rotating shaft A1 of the developing roller 30B. Therefore, the first bearing 60B is arranged between the photoconductor drum 92B and the first pressing member 95B without significantly rotating the casing 10B with respect to the drum frame 91B, and the second bearing 70B is placed on the photoconductor. It can be arranged between the drum 92B and the second pressing member 951B. Therefore, the user of the image forming apparatus can bring the developing roller 30B closer to the photoconductor drum 92B without performing the operation of rotating the casing 10B significantly.

When the first bearing 60B is arranged between the photoconductor drum 92B and the first pressing member 95B, the first pressing member 95B comes into contact with the second end portion 62B of the first bearing 60B. Then, the elastic force of the first coil spring 96B causes the first pressing member 95B to press the second end portion 62B of the first bearing 60B toward the photoconductor drum 92B. Then, as shown in FIG. 25, the first end portion 61B of the first bearing 60B comes into contact with the first guide surface 93B, and the other portion of the first bearing 60B comes into contact with the second guide surface 94B. As a result, the position of the first bearing 60B with respect to the drum frame 91B is fixed.

Similarly, the second pressing member 951B presses the fourth end 72B of the second bearing 70B toward the photoconductor drum 92B. Then, as shown in FIG. 27, the third end portion 71B of the second bearing 70B comes into contact with the third guide surface 931B, and the other portion of the second bearing 70B comes into contact with the fourth guide surface 941B. As a result, the position of the second bearing 70B with respect to the drum frame 91B is fixed.

Further, with the positions of the first bearing 60B and the second bearing 70B fixed with respect to the drum frame 91, the first pressing member 95B presses the first bearing 60B, and the second pressing member 951B presses the second bearing 70B. do. As a result, the outer peripheral surface of the developing roller 30B comes into contact with the outer peripheral surface of the photoconductor drum 92B. Then, the developing roller 30B is pressed against the photoconductor drum 92B.

As described above, in the present embodiment, the first bearing 60B has the first end portion 61B and the second end portion 62B, and the second end portion 62B is rotatable with respect to the first end portion 61B. Is. Further, the second bearing 70B has a third end portion 71B and a fourth end portion 72B, and the fourth end portion 72B is rotatable with respect to the third end portion 71B. Therefore, the first end portion 61B and the second end portion 62B of the first bearing 60B and the third end portion 71B and the fourth end portion 72B of the second bearing 70B are used with respect to the photoconductor drum 92B. The developing roller 30B can be positioned.

Further, in the present embodiment, when the developing cartridge 1B is mounted on the drum cartridge 2B, the first bearing 60B and the second bearing 70B rotate about the rotation shaft A1. also. Similarly, when the developing cartridge 1B is removed from the drum cartridge 2B, the first bearing 60B and the second bearing 70B rotate about the rotation shaft A1. Therefore, the first bearing 60B and the second bearing 70B can be rotated without rotating the casing 10B, and the operation of attaching and detaching the developing cartridge 1B to the drum cartridge 2B can be smoothly performed.

<2-5. About voltage supply>
The first pressing member 95B and the first coil spring 96B are conductive. The first pressing member 95B is made of, for example, a conductive resin. The first coil spring 96B is made of, for example, metal. Further, the drum cartridge 2B includes an electrode terminal 98B that makes electrical contact with the first coil spring 96B. As shown in FIGS. 12 and 13, the electrode terminals 98B are exposed on the outer surface of the drum frame 91B. Further, as described above, the developing roller shaft 32B and the first bearing 60B are also conductive. Therefore, when the developing cartridge 1B is mounted on the drum cartridge 2B and the first pressing member 95B comes into contact with the first bearing 60B, the electrode terminal 98B, the first coil spring 96B, the first pressing member 95B, and the first bearing 60B , And the developing roller shaft 32B are electrically conductive with each other.

When the developing cartridge 1B mounted on the drum cartridge 2B is mounted on the image forming apparatus, the electrode terminal of the image forming apparatus and the electrode terminal 98B of the drum cartridge 2B come into contact with each other. Then, a bias voltage is supplied from the image forming apparatus to the developing roller shaft 32B via the electrode terminal 98B, the first coil spring 96B, the first pressing member 95B, and the first bearing 60B. As a result, the developer is attracted to the outer peripheral surface of the developing roller body 31B by the electrostatic force due to the bias voltage.

As described above, in the present embodiment, the bias voltage is supplied to the first bearing 60B of the developing cartridge 1B via the first pressing member 95B of the drum cartridge 2B. In this way, the number of parts of the drum cartridge 2B can be reduced as compared with the case where a conductive part for supplying a voltage to the first bearing 60B is provided separately from the first pressing member 95B. Therefore, the drum cartridge 2B can be miniaturized.

Further, the first bearing 60B of the present embodiment has (1) a function as a bearing that rotatably supports the developing roller shaft 32B, and (2) a photoconductor drum 92B when the developing cartridge 1B is mounted on the drum cartridge 2B. It functions as a positioning member for positioning the developing roller 30B and (3) as a developing electrode for supplying a bias voltage to the developing roller shaft 32B. Therefore, as compared with the case where these functions are realized by separate members, the number of parts of the developing cartridge 1B can be reduced and the developing cartridge 1B can be miniaturized.

<2-6. Separation operation>
After the developing cartridge 1B is mounted on the image forming apparatus in a state of being mounted on the drum cartridge 2B, the developing cartridge 1B can be separated by the driving force supplied from the image forming apparatus. The separation operation is an operation of temporarily separating the developing roller 30B from the photoconductor drum 92B. For example, when monochrome printing is performed in the image forming apparatus, the developing cartridges 1B of each color other than black perform a separation operation. However, the black developing cartridge 1 may perform a separating operation.

When the developing cartridge 1B is mounted on the drum cartridge 2B as shown in FIGS. 25 and 27, the developing cartridge 1B is arranged at a contact position where the developing roller 30B contacts the photoconductor drum 92B. The position of the first lever 110B at this time is the first position. At the first position, the second convex portion 115B of the first lever 110B is separated from the inner surface of the lever receiving portion 68B of the first bearing 60B. Therefore, the second convex portion 115B of the first lever 110B does not press the inner surface of the lever receiving portion 68B. Further, the cam surface 113B of the first lever 110B is in contact with the drum frame 91B. The position of the separation lever 97B at this time is the third position. At the third position, the second lever arm 972B of the separation lever 97B is separated from the pressed projection 701B of the second bearing 70B. Therefore, the second lever arm 972B of the separation lever 97B does not press the pressed projection 701B of the second bearing 70B.

The image forming apparatus applies a driving force to one end 111B of the first lever 110B when performing the separation operation. Specifically, the image forming apparatus operates a drive lever (not shown). Then, the drive lever presses one end 111B of the first lever 110B as shown by the broken line arrow in FIG. 26. As a result, the first lever 110B rotates from the first position to the second position around the cam surface 113B. At this time, the other end 112B of the first lever 110B moves in a direction away from the photoconductor drum 92B and presses the inner surface of the lever receiving portion 68B of the first bearing 60B. Specifically, the other end 112B of the first lever 110B presses the second end 62B of the first bearing 60B in a direction away from the developing roller 30B against the pressing force of the first pressing member 95B. As a result, the first bearing 60B moves away from the photoconductor drum 92B together with the other end 112B of the first lever 110B.

Further, the image forming apparatus applies a driving force to the first lever arm 971B of the separation lever 97B when performing the separation operation. Specifically, the image forming apparatus operates another drive lever (not shown). Then, the drive lever presses the first lever arm 971B as shown by the broken line arrow in FIG. 28. As a result, the separation lever 97B rotates from the third position to the fourth position with respect to the rotation axis extending in the first direction. At this time, the second lever arm 972B of the separation lever 97B moves in the direction away from the photoconductor drum 92B and presses the pressed projection 701B of the second bearing 70B. Specifically, the second lever arm 972B presses the fourth end portion 72B of the second bearing 70B in the direction away from the developing roller 30B against the pressing force of the second pressing member 951B. As a result, the second bearing 70B moves away from the photoconductor drum 92B together with the second lever arm 972B.

As a result, the casing 10B and the developing roller 30B move away from the photoconductor drum 92B together with the first bearing 60B and the second bearing 70B. As a result, the outer peripheral surface of the developing roller 30B is separated from the outer peripheral surface of the photoconductor drum 92B. That is, the developing cartridge 1B moves from the above-mentioned contact position to the separated position with respect to the drum cartridge 2B.

As described above, in the present embodiment, the other end 112B of the first lever 110B receives the lever of the first bearing 60B according to the force received by the one end 111B of the first lever 110B from the drive lever of the image forming apparatus. The inner surface of the portion 68B is pressed. As a result, a force for moving the developing cartridge 1B from the contact position to the separated position can be applied. That is, the driving force supplied from the image forming apparatus by the first lever 110B having one end 111B that functions as a force point, the other end 112B that functions as an action point, and a cam surface 113B that functions as a fulcrum. It can be transmitted to the first bearing 60B.

That is, the driving force supplied from the image forming apparatus is transmitted to the first bearing 60B of the developing cartridge 1B without going through the drum cartridge 2B. In this way, it is not necessary to provide a component for relaying the driving force at one end of the drum cartridge 2B in the first direction. Therefore, the number of parts of the drum cartridge 2B can be reduced. Therefore, the drum cartridge 2B can be miniaturized.

Further, in the developing cartridge 1B, one end portion 111B of the first lever 110B has a first convex portion 114B protruding in the first direction. Therefore, the surface area of one end 111B of the first lever 110B is larger than that without the first convex 114B. Therefore, the drive lever of the image forming apparatus can stably press one end 111B of the first lever 110B during the separation operation. As a result, the separation operation of the image forming apparatus is stabilized.

Further, in the developing cartridge 1B, the first bearing 60B and the second bearing 70B supporting the developing roller shaft 32B are subjected to pressing force during the separating operation. Therefore, the number of parts of the developing cartridge 1B can be reduced as compared with the case where a member that receives a pressing force during the separation operation is provided separately from the first bearing 60B and the second bearing 70B. Therefore, the development cartridge 1B can be miniaturized.

Further, the first bearing 60B is rotatable about the rotation shaft A1. Therefore, the first lever 110B can press the inner surface of the lever receiving portion 68B of the first bearing 60B in the optimum direction.

Further, when the developing cartridge 1B moves from the contact position to the separated position, the first bearing 60B moves along the second guide surface 94B. As a result, the first lever 110B can press the first bearing 60B while maintaining the position of the first bearing 60B about the rotation shaft A1. Further, when the developing cartridge 1B moves from the contact position to the separated position, the second bearing 70B moves along the fourth guide surface 941B. As a result, the separation lever 97B can press the second bearing 70B while maintaining the position of the second bearing 70B about the rotation shaft A1.

<3. Modification example>
Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment. Hereinafter, various modifications will be described focusing on the differences from the above-described embodiments.

In the above embodiment, the developing cartridge 1 includes a first bearing and a second bearing. Then, both the first bearing and the second bearing were rotatable with respect to the casing 10. However, the second bearing may not be rotatable with respect to the casing 10. Further, the developing cartridge 1 does not have to be provided with the second bearing. In that case, the first bearing may be arranged at either end of the casing 10 in the first direction.

In the above embodiment, the developing cartridge 1 is attached to the drum cartridge 2 having one photoconductor drum 92. However, the developing cartridge 1 may be mounted on a drum cartridge having a plurality of photoconductor drums 92.

Further, the detailed shape of the developing cartridge 1 may be different from the shape shown in each drawing of the present application. Further, the elements appearing in the above-described embodiments and modifications may be appropriately combined as long as there is no contradiction.

1,1B Development cartridge 2,2B Drum cartridge 10,10B Casing 15B Casing protrusion 16B Claw part 20,20B Agitator 30,30B Development roller 40 Supply roller 50,50B Gear part 60,60B 1st bearing 70,70B 2nd bearing 91 , 91B Drum frame 92,92B Photoreceptor drum 110,110B 1st lever 120,120B Holder A1 Rotating shaft

Claims (12)

It ’s a developing cartridge,
A developing roller having a developing roller shaft extending in the first direction,
A casing capable of accommodating a developing agent, wherein the developing roller is located at one end in a second direction intersecting with the first direction.
It has a first end that is electrically connected to the developing roller shaft and a second end that is more distant from the developing roller shaft than the first end and is movable with the casing and the developing roller. The developing electrode, the second end of which is a developing electrode that is more distant from the first end of the casing in the second direction than the first end, and is rotatable about the developing roller shaft. With the developing electrode
A first lever that can be moved with respect to the casing
A holder that movably holds the first lever with respect to the casing,
With
In the state where the first lever is held, the holder prevents the first lever from coming out of the holder from one side to the other in the third direction intersecting with the first direction and the second direction. Stop,
The first lever is a developing cartridge, characterized in that the rotation of the developing electrode from one side to the other in the third direction is stopped. The developing cartridge according to claim 1.
The developing cartridge is characterized in that the holder stops the movement of the first lever from one side to the other in a third direction intersecting with the first direction and the second direction. The developing cartridge according to claim 2.
The first lever
One end and
The other end, which is separated from the one end toward the other side in the third direction,
Have,
The one end
It has a first convex portion that protrudes in the first direction.
The developing cartridge is characterized in that the holder comes into contact with the first convex portion to stop the movement of the first lever from one side to the other in the third direction. The developing cartridge according to claim 3.
The developing electrode is
It has a first hole extending in the third direction between the first end portion and the second end portion, and has a first hole into which the other end portion of the first lever is inserted.
A developing cartridge, wherein the other end of the developing electrode comes into contact with the developing electrode to stop the rotation of the developing electrode from one side to the other in the third direction. The developing cartridge according to claim 4.
The developing electrode is
It has a lever receiving portion located inside the first hole and has a lever receiving portion.
The first lever
It has a second convex portion that protrudes from the other end in the first direction.
The developing cartridge, characterized in that the second convex portion comes into contact with the lever receiving portion to stop the rotation of the developing electrode from one side to the other in the third direction. The developing cartridge according to any one of claims 1 to 5.
The casing is
It has a casing protrusion extending in the first direction.
The developing cartridge, characterized in that the casing protrusion stops the rotation of the developing electrode from the other side to one side in the third direction. The developing cartridge according to claim 6.
The developing electrode is
It has an electrode projection extending in the first direction and has
A developing cartridge, characterized in that the casing protrusions come into contact with the electrode protrusions to stop the rotation of the developing electrode from the other side to one side in the third direction. The developing cartridge according to any one of claims 1 to 7.
The developing roller shaft has an annular engaging groove on the outer peripheral surface, and has an annular engaging groove.
The developing electrode is
The first insertion hole into which the developing roller shaft is inserted, and
A wall portion protruding from a part of the peripheral edge portion of the first insertion hole toward the engaging groove, and a wall portion.
Have,
A developing cartridge, characterized in that, when the first lever engaged with the developing electrode is held by the holder, the wall portion is inserted into the engaging groove. The developing cartridge according to any one of claims 1 to 8.
The developing electrode is attached to one end of the developing roller shaft in the first direction.
The developing cartridge is
A bearing mounted on the other end of the developing roller shaft in the first direction, the third end having a second insertion hole into which the other end of the developing roller shaft is inserted, and the third end. A developing cartridge comprising a fourth end portion that is more distant from the developing roller shaft than the portion, and further comprising a bearing that is movable with the casing and the developing roller. The developing cartridge according to claim 9.
The bearing is
A second hole extending in the first direction between the third end and the fourth end,
The claw receiving portion located inside the second hole and
Have,
The casing is
A developing cartridge which is a claw portion extending in the first direction and has a claw portion whose tip protrudes in a direction intersecting with the first direction and engages with the claw receiving portion. The developing cartridge according to claim 10.
The bearing is rotatable about the developing roller shaft and
A developing cartridge characterized in that the claw portion stops the rotation of the bearing by coming into contact with the bearing. The developing cartridge according to any one of claims 9 to 11.
The developing cartridge is used for a drum cartridge having a photoconductor drum.
The drum cartridge has a separating lever that is rotatable about an axis extending in the first direction.
The bearing is
A developing cartridge that is a pressed protrusion that projects in a direction away from the casing and has a pressed protrusion that can come into contact with the separation lever.

Images