JP4349346B2 - Developing cartridge and process unit - Google Patents

Description

  The present invention relates to a developing cartridge and a process unit that can be used in an image forming apparatus that forms an image by developing an electrostatic latent image formed on an image carrier.

2. Description of the Related Art Conventionally, an image forming apparatus that forms an image by developing an electrostatic latent image formed on a photosensitive drum is known.
This type of image forming apparatus includes a process unit configured to be detachable in order to facilitate toner supply. This process unit includes a photosensitive cartridge that houses a peripheral mechanism around a photosensitive drum (image carrier), a toner tank that contains toner, a developing roller that carries toner and supplies it to the photosensitive drum, and the like. And a developing cartridge that houses a mechanism for developing using toner. The developing cartridge is configured to be detachable from the photosensitive cartridge.

  When the developing cartridge is mounted on the photosensitive cartridge, the surface of the developing roller needs to press the surface of the photosensitive drum. This is because it is necessary to supply a thin layer of the developer formed on the surface of the developing roller to the electrostatic latent image on the surface of the photosensitive drum during the image forming operation.

For this purpose, there is known a process unit in which an urging means (for example, a spring) for urging the developing cartridge is provided on the photosensitive cartridge side, and an actuated portion on which the urging means acts is provided on the developing cartridge side. . Note that the actuated portion is integrally formed on the housing of the developing cartridge (see, for example, Patent Document 1).
JP 2000-250378 A

  By the way, when changing the type of toner or the material of the developing roller, it is necessary to change the magnitude of the force that the developing roller urges the photosensitive drum according to the toner type and the roller material. There is.

  If the urging means is provided on the photosensitive cartridge side as described in the above-mentioned Patent Document 1, in order to change the magnitude of the urging force, A method of changing the shape is conceivable. However, as described above, since the housing of the developing cartridge and the affected part are integrally formed, the type of the housing of the developing cartridge has to be changed according to the change of the toner type and the roller material. There was a problem.

  Further, when the developer cartridge is refilled (refilled), there is a problem that a different type of toner from the toner that has been filled when it is new cannot be used. This is because, when different types of toner are filled, a developing cartridge having a casing of a type corresponding to the filled toner type is required in order to change the magnitude of the urging force.

  The present invention has been made in view of these problems, and an object thereof is to provide a developing cartridge and a process unit that can easily change the urging force according to a change in toner type or the like.

In order to achieve the above object, the invention according to claim 1 is a development in which an electrostatic latent image is detachably mounted on a photosensitive cartridge having a rotatable image carrier on which an electrostatic latent image is formed. A cartridge, which is a rotatable developer carrier on which the developer is carried on the outer peripheral surface for developing the electrostatic latent image into a visible image, and a shaft of the developer carrier. A developer cartridge housing having a first support plate rotatably supported at one end in the direction and a second support plate rotatably supported at the other end in the axial direction of the developer carrier A transmission gear that is attached to the outer side of the first support opposite to the side on which the developer carrier is disposed across the first support plate, and that transmits a rotational driving force to the developer carrier; Install the developer cartridge housing outside to cover the transmission gear. The outer surface of the second support plate is covered with the first covering member to be attached and the second support outer side opposite to the side on which the developer carrier is disposed with the second support plate interposed therebetween. As described above, the second covering member attached to the developing cartridge housing and the plurality of types of urging means set to the urging force corresponding to the toner type and roller material are used in accordance with the toner type and roller material of the developing cartridge. It is selected and attached to each of the first covering member and the second covering member in a replaceable manner, and when the developing cartridge is attached to the photosensitive member cartridge, the developer carrying member presses the image carrier. And a first urging means for applying a force.

In other words, the first urging means is installed not on the photosensitive cartridge side but on the developing cartridge side.
Therefore, according to the developing cartridge of the present invention, when the magnitude of the force with which the developing roller urges the photosensitive drum is changed according to the change in the toner type and the roller material, the first urging means is What is necessary is just to replace | exchange for the 1st urging means set to the urging | biasing force according to the change of a toner kind and roller material.

  That is, if a plurality of types of first urging means set to the urging force according to the change in toner type and roller material are prepared in advance, the urging force can be easily obtained by replacing the first urging means. Can be adjusted.

  The first covering member and the second covering member are attached to both ends of the developer cartridge in the axial direction of the developer carrier (hereinafter referred to as the developing shaft direction). That is, the first urging means presses both end portions in the developing axis direction of the developing cartridge. That is, by pressing the developing cartridge at both ends, the force with which the developer carrier presses the image carrier can be made uniform over the developing axis direction.

  Incidentally, a transmission gear or the like is attached to the outer side of the first support, and a toner supply port or the like is attached to the outer side of the second support. For this reason, when the first urging means is attached to both ends of the developing cartridge, the attachment positions are limited so as not to impair the functions of the transmission gear, the toner supply port, and the like.

  On the other hand, in the developing cartridge of the present invention, since the first urging means is attached to the first covering member that covers the transmission gear outside the first support and the second covering member that covers the second supporting outside, both ends of the developing cartridge are used. In the portion, the restriction on the mounting position of the first urging means can be relaxed.

  In order to apply a biasing force so that the developer carrying member presses the image carrying member when the developing cartridge is mounted on the photosensitive member cartridge, specifically, as described in claim 2. In addition, the photosensitive cartridge includes a housing portion that houses the developing cartridge, and the first biasing member generates a biasing force by contacting the housing portion when the developing cartridge is housed in the housing portion. What is necessary is just to make it.

  In the developing cartridge configured as described above, the urging member abuts on the housing portion when the developing cartridge is housed in the housing portion and generates a biasing force. That is, the urging member urges the developing cartridge by a reaction that urges the housing portion of the photosensitive cartridge. Thus, only when the developing cartridge is mounted on the photosensitive cartridge, the urging member urges the developer carrying member to press the image carrying member.

  In the developing cartridge according to claim 2, the urging member is preferably a spring as described in claim 3. That is, the urging member can be configured with simple components.

  Further, in the developing cartridge according to any one of claims 1 to 3, as described in claim 4, the developing cartridge housing and the first covering member and the second covering member are separate. Good.

In the developing cartridge configured as described above, it is not necessary to prepare a plurality of developing cartridge housing molds according to the toner type and the roller material.
According to a fourth aspect of the present invention, in the developing cartridge according to the fifth aspect, the first covering member and the second covering member may be detachably attached to the developing cartridge housing.

In the developing cartridge configured as described above, the first covering member and the second covering member can be easily replaced.
According to a sixth aspect of the present invention, there is provided a rotatable developer carrying member on which the developer is carried on the outer peripheral surface for developing the electrostatic latent image into a visible image. Development that is detachably mounted on a photosensitive cartridge having a rotatable image carrier formed on the outer peripheral surface and a second urging means for urging the developer carrier to the image carrier. A first support plate that rotatably supports the developer carrying member at one end in the axial direction of the developer carrying member; and the developer carrying member that rotates at the other end in the axial direction of the developer carrying member. A developer cartridge housing having a second support plate that supports the developer, and a developer support body attached to the outer side of the first support opposite to the side on which the developer carrier is disposed with the first support plate interposed therebetween; A transmission gear for transmitting rotational driving force to the carrier, and a transmission gear on the outer side of the first support. In this way, on the outer side of the second support, which is opposite to the side on which the developer carrier is disposed with the second support plate sandwiched between the first covering member detachably attached to the developer cartridge housing, The second energizing member is detachably attached to the developing cartridge housing so as to cover the outer surface of the second support of the support plate , and the second energizing is set at different positions according to the toner type and the roller material. The developing unit is selected from a plurality of types of affected parts whose urging force changes according to the toner type and roller material of the developing cartridge, and is exchangeably attached to each of the first covering member and the second covering member. And an actuated portion to which the urging force of the second urging means acts when the developing cartridge is mounted on the photosensitive cartridge.

  That is, when the developing cartridge is attached to the photosensitive cartridge, the second urging means provided in the photosensitive cartridge urges the actuated portion attached to the developing cartridge. As a result, only when the developing cartridge is mounted on the photosensitive member cartridge, the second urging means urges the developer carrier to press the image carrier.

  Therefore, in the developing cartridge of the present invention, when the magnitude of the force that the developing roller urges the photosensitive drum is changed according to the change in the toner type or the roller material, the change in the toner type or the roller material is performed. What is necessary is just to replace | exchange to an effected part.

  That is, if a plurality of types of actuated portions for setting the energizing force according to the change in toner type and roller material are prepared in advance, the energizing force can be adjusted by a simple operation of replacing the actuated portion. .

  A plurality of types of members in which the first covering member (second covering member) and the acting part are integrally molded (hereinafter referred to as a covering action integral molding member) are prepared according to the toner type and the roller material, When the magnitude of the urging force is changed, it may be replaced with a covering action integral molding member corresponding to the toner type and the roller material.

Specifically, the acted part may be a projecting member projecting from each of the first covering member and the second covering member, as described in claim 7.
That is, by appropriately changing the position of the protruding member on the first covering member (second covering member), the magnitude of the urging force that the second urging means acts on the actuated portion can be changed.

  In order to change the magnitude of the urging force, the first covering member (second covering member) may be configured such that the position of the protruding member on the first covering member (second covering member) can be changed. Further, a plurality of types of covering action integral molding members having different positions of the protruding members on the first covering member (second covering member) may be prepared.

  Further, in the developing cartridge according to any one of claims 6 and 7, as described in claim 8, the developing cartridge housing, the first covering member, and the second covering member are separate. Good.

In the developing cartridge configured as described above, it is not necessary to prepare a plurality of developing cartridge housing molds according to the toner type and the roller material.
Further, in the developing cartridge according to claim 8, as described in claim 9, the first covering member and the second covering member may be detachably attached to the developing cartridge housing.

In the developing cartridge configured as described above, the first covering member and the second covering member can be easily replaced.
A process unit according to a tenth aspect includes a developing cartridge according to any one of the first to fifth aspects, and a photosensitive cartridge to which the developing cartridge according to the first to fifth aspects can be detachably mounted. It is characterized by providing.

  A process unit according to an eleventh aspect includes the developing cartridge according to any one of the sixth to ninth aspects, and a rotatable image carrier on which an electrostatic latent image is formed on an outer peripheral surface. A photosensitive cartridge comprising a second urging unit that detachably mounts the developer cartridge according to any one of claims 6 to 9 and that urges the developer carrier of the mounted developer cartridge to the image carrier. And a body cartridge.

  Since the process unit according to claim 10 or 11 configured as described above has the same configuration as the above-described developing cartridge, the same effect as the above-described developing cartridge can be obtained.

(First embodiment)
A first embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic sectional side view of a laser printer 1 as an image forming apparatus according to an embodiment.

  As shown in FIG. 1, a laser printer 1 includes a top cover 3 serving as an upper surface and a housing 2 having four side surfaces (only a part of which is shown) such as a front side surface 2a and a back side surface 2b. The top cover 3 is recessed inward of the housing 2 to form a paper discharge tray 71. A paper feed cassette 11 capable of storing a plurality of recording sheets is provided at the lower part of the housing 2 so as to be freely inserted and removed from the front side surface 2 a of the housing 2. The front side surface 2a is provided with a manual tray 19 for individually setting recording paper, and a front cover 4 that can be opened and closed.

  The laser printer 1 includes a recording paper (a recording paper conveyance path is represented by a virtual line P in the figure) in a housing 2 provided with a top cover 3, a front cover 4, and a rear cover 5 provided on the back side surface 2b. ), A process unit 25 for forming a developer image that is a visible image on the fed recording paper, and a developer image formed on the recording paper on the recording paper. A fixing unit 60 for fixing the recording paper, a paper discharge unit 70 for discharging the recording paper that has passed through the fixing unit 60, and the like.

  The paper supply unit 10 includes a paper supply cassette 11, paper supply rollers 14 and 15 provided above the front end (front side) end of the recording paper stacked in the paper supply cassette 11 in the conveyance direction, and a paper supply pad. 16 and the like. The paper feed unit 10 is provided with a paper feed path KP that is a recording paper transport path that reverses the recording paper fed from the paper feed cassette 11 and transports it to the lower part of the process unit 25. 10 includes a registration roller pair 18 facing the paper feed path KP. In addition to the recording paper in the paper feeding cassette 11, the recording paper manually set on the manual feed tray unit 19 is also fed to the paper feeding path KP. After stopping, the image data is supplied to the process unit 25 in accordance with the image formation timing in the process unit 25.

  The paper feed cassette 11 is disposed below the process unit 25 and the fixing unit 60. In the paper feed cassette 11, a paper pressing plate 12 and a spring 13 are provided. The sheet pressing plate 12 is capable of stacking recording sheets in a stack, and is supported so as to be swingable at the end far from the sheet feed roller 14 and the like, so that the near end can move in the vertical direction. It is said that. The spring 13 is provided so as to urge the back surface of the end of the paper pressing plate 12 closer to the paper feed roller 14 and the like upward. Therefore, the paper pressing plate 12 is swung downward against the urging force of the spring 13 with the end farther from the paper feed roller 14 and the like as a fulcrum as the amount of recording paper stacked increases.

  The paper feed roller 15 and the paper feed pad 16 are disposed to face each other, and the paper feed pad 16 is pressed toward the paper feed roller 15 by a spring 17 provided on the back side of the paper feed pad 16. The uppermost recording paper layered on the paper pressing plate 12 is pressed against the paper feed roller 14 by the spring 13 from the back side of the paper pressing plate 12, and the uppermost recording paper is fed. After the sheet is fed by the roller 14 and sandwiched between the sheet feeding roller 15 and the sheet feeding pad 16, the sheet feeding roller 15 rotates and is separated one by one by the sheet feeding roller 15 and the sheet feeding pad 16. However, the paper is fed toward the paper feed path KP.

  The recording paper fed from the paper feed cassette 11 or the manual feed tray unit 19 is sent to a pair of registration rollers 18 disposed above the paper feed roller 14 and the like. The registration roller pair 18 corrects the skew of the fed recording paper and then transports the recording paper to the process unit 25.

  A scanning unit 50 provided above the process unit 25 includes a laser light emitting unit (not shown), a polygon mirror 51 that is driven to rotate at high speed, a first scanning lens (fθ lens) 52, a second scanning lens (cylindrical lens) 53, and a return. As shown by a two-dot chain line, a polygon mirror 51, a first scanning lens 52, and a folding mirror 54 are provided as shown by a two-dot chain line. The surface of the photosensitive drum 31 in the process unit 25 is exposed and scanned by passing or reflecting the second scanning lens 53 and the folding mirror 55 in this order.

The process unit 25 includes a photoconductor cartridge 30 and a developing cartridge 40.
Among these, the developing cartridge 40 is detachably attached to the photoreceptor cartridge 30 and includes a developing roller 41, a layer thickness regulating blade 42, a supply roller 43, a hopper 44, and the like.

  The developer in the hopper 44 is agitated by the rotation of the agitator 46 supported by the rotating shaft 45 in the direction of the arrow, and is discharged from the supply port 47 opened on the side of the hopper 44. A supply roller 43 is rotatably disposed at a side position of the supply port 47, and a developing roller 41 is rotatably disposed so as to face the supply roller 43. The supply roller 43 and the developing roller 41 are in contact with each other in a state where each of them is compressed to some extent.

  The developing roller 41 has a metal roller shaft covered with a roller made of a conductive rubber material, and is driven to rotate in the direction of the arrow (counterclockwise). The developing roller 41 is configured to be applied with a developing bias. A layer thickness regulating blade 42 is disposed in the vicinity of the developing roller 41. The layer thickness regulating blade 42 includes a pressing portion having a semicircular cross section made of insulating silicone rubber at the tip of a blade body made of a metal leaf spring material. The pressing portion is configured to be pressed against the developing roller 41 by the elastic force of the blade body.

  The developer discharged from the supply port 47 is supplied to the development roller 41 by the rotation of the supply roller 43. At this time, the developer is positively frictionally charged between the supply roller 43 and the development roller 41. The developer supplied above enters between the pressing portion of the layer thickness regulating blade 42 and the developing roller 41 as the developing roller 41 rotates, and is carried on the developing roller 41 as a thin layer having a constant thickness. Is done.

The photoreceptor cartridge 30 includes a photoreceptor drum 31, a charger 32, a transfer roller 33, and the like.
The photosensitive drum 31 is supported by the photosensitive cartridge 30 so as to be rotatable in the arrow direction (clockwise) in a state of facing the developing roller 41 at a side position of the developing roller 41. The photoreceptor drum 31 is formed of a positively chargeable photosensitive layer whose drum body is grounded and whose surface is made of polycarbonate or the like.

  The charger 32 is disposed opposite to the upper left of the photosensitive drum 31 in a diagonal direction at a predetermined interval. The charger 32 is a scorotron charger for positive charging that generates corona discharge from a charging wire such as tungsten, and is configured to uniformly charge the surface of the photosensitive drum 31 to a positive polarity. Yes.

  The transfer roller 33 is disposed below the photoconductive drum 31 so as to face the photoconductive drum 31 and is supported by the photoconductive cartridge 30 so as to be rotatable in an arrow direction (counterclockwise). The transfer roller 33 is configured such that a metal roller shaft is covered with a roller made of a conductive rubber material, and a transfer bias is applied during transfer. Therefore, a visible image (toner image) carried on the surface of the photosensitive drum 31 is recorded while the recording paper passes between the photosensitive drum 31 and the transfer roller 33 (hereinafter referred to as a transfer nip portion). It is transferred to paper.

  As the photosensitive drum 31 rotates, the surface of the photosensitive drum 31 is first uniformly charged to the positive polarity by the charger 32, and then exposed to the electrostatic beam by the laser beam from the scanning unit 50. A latent image is formed.

  Next, when the developing roller 41 rotates, the positively charged developer carried on the developing roller 41 is formed on the surface of the photosensitive drum 31 when it contacts the photosensitive drum 31. The electrostatic latent image, that is, the developer is supplied to and selectively carried on the exposed portion of the surface of the photosensitive drum 31 that is uniformly positively charged and exposed to a laser beam and whose potential is lowered. An image is formed (reversal development).

  Thereafter, the developer image carried on the surface of the photosensitive drum 31 is transferred to the transfer roller 33 while the recording paper passes between the photosensitive drum 31 and the transfer roller 33 (transfer nip portion). The image is transferred to the recording paper by the bias.

  The fixing unit 60 is disposed on the upper side of the paper feed cassette 11, on the side of the process unit 25 and on the downstream side of the process unit 25 in the recording paper conveyance direction. The fixing unit 60 includes a heating roller 61 including a heater, and a pressure roller 62 provided to face the heating roller 61 and press the surface of the heating roller 61. The heating roller 61 is formed in a metal cylinder shape, and both ends thereof are opened, and a heater made of, for example, a halogen lamp is provided therein, and is configured to be heated by the heater.

  The pressure roller 62 is obtained by winding a PTFE (polytetrafluoroethylene) film on the surface of an elastic body such as silicone rubber. The pressure roller 62 presses the heating roller 61 and is attached to the heating roller 61. Followed and rotated.

  In the fixing unit 60, the developer image, which is a visible image transferred on the recording paper in the process unit 25, is thermally fixed while the recording paper passes between the heating roller 61 and the pressure roller 62, and thereafter The recording paper is sent to a paper discharge path HP which is a recording paper conveyance path formed in the paper discharge unit 70.

  The paper discharge unit 70 includes a paper discharge tray 71 provided on the top cover 3, an inner guide member 72 and an outer guide member 73 that constitute the paper discharge path HP, and a discharge that discharges the recording paper onto the paper discharge tray 71. A pair of discharge rollers 74 provided at the outlet.

  The paper discharge tray 71 has a substantially rectangular plate shape in plan view, and a rear end is recessed into the housing 2 to form a concave portion, and is gradually inclined upward from the rear end toward the front. It is the composition to do. The recording paper that has passed through the fixing unit 60 and has been sent to the paper discharge path HP is fed to the paper discharge roller pair 74 by the inner guide member 72 and the outer guide member 73 inverting the paper traveling direction upward. Then, the paper is discharged on the paper discharge tray 71 toward the front side via the paper discharge roller pair 74.

  2 is a plan view of the developing cartridge 40, FIG. 3 is a left side view of the developing cartridge 40 without the gear holder 120, FIG. 4 is a left side view of the developing cartridge 40 with the gear holder 120 attached, and FIG. FIG. 6 is a right side view of the developing cartridge 40 when the dummy holder 140 is not attached, and FIG. 6 is a right side view of the developing cartridge 40 when the dummy holder 140 is attached.

  As shown in FIG. 2, the developing cartridge 40 includes a cartridge housing 101 having an opening at the rear end (upper end in FIG. 2) and formed in a box shape, and a developing roller is provided in the cartridge housing 101. 41, a layer thickness regulating blade 42, a supply roller 43, a hopper 44, and the like.

  As shown in FIG. 3, a gear mechanism 102 for driving the developing roller 41, the supply roller 43, and the agitator 46 is provided on the left side surface 101 a (left side in FIG. 2) of the cartridge housing 101.

  The gear mechanism 102 meshes with the developing roller driving gear 103 for driving the developing roller 41, the supplying roller driving gear 104 for driving the supplying roller 43, the developing roller driving gear 103, and the supplying roller driving gear 104. , An input gear 105 for transmitting a rotational driving force from a power source (not shown) to the developing roller driving gear 103 and the supply roller driving gear 104, an agitator driving gear 106 for driving the agitator 46, the input gear 105 and the agitator driving gear. 106, and an idle gear 107 that transmits the rotational driving force from the input gear 105 to the agitator driving gear 106.

  2 and 4, the developing roller driving gear 103, the supply roller driving gear 104, the input gear 105, the agitator driving gear 106, the idle gear 107 and the like are covered outside the left side surface 101a of the cartridge housing 101. A gear holder 120 is detachably attached.

  The gear holder 120 has support openings 121a, 121b, and 121c that are opened in a circular shape to rotatably support the developing roller drive gear 103, the input gear 105, and the agitator drive gear 106, respectively.

  Further, the gear holder 120 is provided with a biasing portion 160 that applies a biasing force so that the developing roller 41 presses the photosensitive drum 31 when the developing cartridge 40 is mounted on the photosensitive cartridge 30.

  As shown in FIG. 4, the urging portion 160 includes a contact portion 161 that contacts the photoconductor cartridge 30 in a state where the developing cartridge 40 is mounted on the photoconductor cartridge 30 (hereinafter referred to as a cartridge mounting state), and the gear holder 120. And a slide support member 162 slidably supporting the contact portion 161, and one end fixed to the contact portion 161 along the sliding direction of the contact portion 161 and the other end of the slide support member 162. And a coiled spring 163 fixed to the head.

In the present embodiment, the sliding direction is set so as to coincide with the substantially horizontal direction when the cartridge is mounted.
As shown in FIG. 5, a circular outer peripheral edge is formed to protrude from the right side surface 101 b on the right side surface 101 b (right side in FIG. 2) of the cartridge housing 101, and an opening for supplying toner into the hopper 44. A toner cap 111 as a lid for opening and closing the opening, a reinforcing rib 112 for reinforcing the outer peripheral edge of the opening, and detecting the remaining amount of toner by transmitting light A toner empty detection window 113 is provided.

  As shown in FIGS. 2 and 6, a dummy holder 140 that covers a part of the outside of the right side surface 101 b is detachably attached to the outside of the right side surface 101 b of the cartridge housing 101.

  Further, the urging portion 160 is attached to the dummy holder 140 at a position substantially symmetrical to the urging portion 160 attached to the gear holder 120 with respect to the center line in the longitudinal direction of the cartridge housing 101.

FIG. 7 is a side sectional view of the process unit 25 for explaining a state where the developing cartridge 40 is mounted on the photosensitive cartridge 30 (cartridge mounted state).
As shown in FIG. 7, the cartridge housing 180 of the photoconductor cartridge 30 includes a first housing portion 181 that houses components such as the photoconductor drum 31, the charger 32, and the transfer roller 33, and a first housing that houses the developing cartridge 40. 2 accommodating portion 182.

  Among these, the second housing portion 182 is open at the top, and is configured so that the developing cartridge 40 can be attached and detached from above. 7 shows a state in which the developing cartridge 40 indicated by a two-dot chain line is removed from the photosensitive member cartridge 30, and the developing cartridge 40 indicated by a broken line in FIG. Indicates the state.

  In addition, an actuated portion 183 is formed on the inner side of the second housing portion 182 for the biasing portion 160 of the developing cartridge 40 to apply a biasing force to the photosensitive cartridge 30 when the cartridge is mounted.

In the process unit 25 configured as described above, the urging unit 160 is installed not on the photosensitive cartridge 30 side but on the developing cartridge 40 side.
Therefore, when the magnitude of the force with which the developing roller 41 urges the photosensitive drum 31 is changed according to the change in the toner type and the roller material, the urging unit 160 is used to change the toner type and the roller material. What is necessary is just to replace | exchange for the biasing part 160 set to the biasing force according to.

  That is, if a plurality of types of urging units 160 set to urging forces according to changes in toner type and roller material are prepared in advance, the urging force can be adjusted by a simple operation of replacing the urging unit 160. it can.

  The cartridge housing 101 is separate from the gear holder 120 and the dummy holder 140. That is, the cartridge housing 101, the gear holder 120, and the dummy holder 140 are not integrally formed. For this reason, it is not necessary to prepare a plurality of types of cartridge housings 101 according to the toner type and roller material.

  Since the gear holder 120 and the dummy holder 140 are detachably attached to the cartridge housing 101, the gear holder 120 and the dummy holder 140 can be easily replaced.

  The gear holder 120 and the dummy holder 140 are attached to both ends of the developing cartridge 40 in the axial direction of the developing roller 41 (hereinafter referred to as the developing shaft direction). That is, the urging unit 160 presses both end portions of the developing cartridge 40 in the developing axis direction. That is, by pressing the developing cartridge 40 at both ends, the force with which the developing roller 41 presses the photosensitive drum 31 can be made uniform over the developing axis direction.

  Further, both ends of the developing cartridge 40 are attached to the gear holder 120 that covers the gear mechanism portion 102 outside the left side surface 101 a of the cartridge housing 101 and the dummy holder 140 that covers the outside of the right side surface 101 b of the cartridge housing 101. , The restriction on the mounting position of the urging portion 160 can be relaxed.

  Further, the urging unit 160 abuts on the second storage unit 182 (acted portion 183) to generate a urging force when the developing cartridge 40 is stored in the second storage unit 182. That is, the coiled spring 163 of the urging unit 160 urges the developing cartridge 40 by a reaction that urges the second housing portion 182 of the photoreceptor cartridge 30. As a result, only when the developing cartridge 40 is mounted on the photosensitive member cartridge 30, the coiled spring 163 of the urging unit 160 urges the developing roller 41 to press the photosensitive drum 31.

Further, a coil spring 163 is used as a member for generating an urging force (hereinafter referred to as an urging member). For this reason, a biasing member can be comprised by a simple component.
In the embodiment described above, the photosensitive drum 31 is the image carrier in the present invention, the developing roller 41 is the developer carrier in the present invention, the cartridge housing 101 is the developer cartridge housing in the present invention, and the left side surface 101a is in the present invention. The first support plate, the right side surface 101b is the second support plate in the present invention, the gear mechanism 102 is the transmission gear in the present invention, the gear holder 120 is the first covering member in the present invention, the dummy holder 140 is the second covering member in the present invention, The urging portion 160 is the first urging means in the present invention, the second accommodating portion 182 is the accommodating portion in the present invention, and the coiled spring 163 is the “spring” in the present invention.

(Second Embodiment)
A second embodiment of the present invention will be described below with reference to the drawings. In the second embodiment, only parts different from the first embodiment will be described.

  FIG. 8 is a side sectional view of the process unit 25 in the second embodiment for explaining a state in which the developing cartridge 40 is mounted on the photosensitive cartridge 30 (cartridge mounted state).

As shown in FIG. 8, the laser printer 1 according to the second embodiment is different from the laser printer 1 according to the first embodiment in the configuration of the process unit 25.
First, the photosensitive cartridge 30 according to the second embodiment supports the urging unit 190, the point that the actuated portion 183 is omitted, the urging unit 190 for urging the developing cartridge 40, and the urging unit 190. This is the same as the photoconductor cartridge 30 of the first embodiment, except that a support member 186 is formed inside the second housing portion 182.

  Among these, the urging portion 190 is in contact with a contact portion 191 that contacts the developing cartridge 40 in a cartridge-mounted state, and a slide support member 192 that is fixed to the support member 186 and supports the contact portion 191 slidably. A coiled spring 193 having one end fixed to the contact portion 191 and the other end fixed to the slide support member 192 along the sliding direction of the portion 191 is configured.

  Further, in the developing cartridge 40 of the second embodiment, the biasing portion 160 is omitted, and the actuated portion for the biasing portion 190 of the photosensitive cartridge 30 to apply a biasing force to the developing cartridge 40 in the cartridge mounted state. The developing cartridge 40 is the same as the developing cartridge 40 of the first embodiment except that 200 is formed so as to protrude from each of the gear holder 120 and the dummy holder 140.

  The actuated portion 200 is installed at a position where it abuts against the abutting portion 191 of the urging portion 190 when the cartridge is mounted. In addition, the operated part 200 is molded integrally with the gear holder 120 (dummy holder 140).

  In the process unit 25 configured as described above, when the developing cartridge 40 is mounted on the photosensitive cartridge 30, the urging unit 190 provided in the photosensitive cartridge 30 is replaced by the operated part 200 attached to the developing cartridge 40. Energize. As a result, the urging unit 190 urges the developing roller 41 to press the photosensitive drum 31 only when the developing cartridge 40 is attached to the photosensitive cartridge 30.

  Accordingly, when the magnitude of the force with which the developing roller 41 urges the photosensitive drum 31 is changed according to the change in the toner type or the roller material, the actuated portion 200 is changed according to the change in the toner type or the roller material. The gear holder 120 and the dummy holder 140 provided may be replaced.

  That is, if a plurality of types of gear holders 120 and dummy holders 140 for setting urging forces according to changes in the toner type and roller material are prepared in advance, the gear holder 120 and the dummy holders 140 can be replaced with a simple operation. You can adjust the power.

  The actuated portion 200 is a member protruding from each of the gear holder 120 and the dummy holder 140. For this reason, the magnitude | size of the urging | biasing force which the urging | biasing part 190 acts on the to-be-acted part 200 can be changed by changing suitably the position of the to-be-acted part 200 on the gear holder 120 (dummy holder 140).

In the embodiment described above, the urging portion 190 is the second urging means in the present invention, and the operated portion 200 is the operated portion in the present invention.
As mentioned above, although one Example of this invention was described, this invention is not limited to the said Example, As long as it belongs to the technical scope of this invention, a various form can be taken.

  For example, in the said 2nd Embodiment, the to-be-acted part 200 showed what was shape | molded integrally with the gear holder 120 (dummy holder 140). However, you may use the gear holder 120 (dummy holder 140) comprised so that the position of the to-be-acted part 200 on the gear holder 120 (dummy holder 140) was changeable.

  Further, the present invention is not limited to a monochrome laser printer, and may be configured as a color laser printer.

1 is a schematic side sectional view of a laser printer. The top view of a developing cartridge. The left view of the developing cartridge in the state where the gear holder is not attached. FIG. 4 is a left side view of the developing cartridge in a state where a gear holder is attached. The right view of the developing cartridge in the state where the dummy holder is not attached. FIG. 4 is a right side view of the developing cartridge in a state where a dummy holder is mounted. FIG. 4 is a side sectional view of the process unit for explaining a cartridge mounting state in the first embodiment. The sectional side view of the process unit for demonstrating the cartridge mounting state in 2nd Embodiment.

  DESCRIPTION OF SYMBOLS 1 ... Laser printer, 2 ... Housing, 2a ... Front side surface, 2b ... Back side surface, 3 ... Top cover, 4 ... Front cover, 5 ... Rear cover, 10 ... Paper feed part, 11 ... Paper feed cassette, 12 ... Paper pressing plate, 13 ... spring, 14, 15 ... feed roller, 16 ... feed pad, 17 ... spring, 18 ... registration roller pair, 19 ... bypass tray section, 25 ... process unit, 30 ... photosensitive cartridge, 31 DESCRIPTION OF SYMBOLS ... Photosensitive drum, 32 ... Charger, 33 ... Transfer roller, 40 ... Developing cartridge, 41 ... Developing roller, 42 ... Layer thickness control blade, 43 ... Supply roller, 44 ... Hopper, 45 ... Rotating shaft, 46 ... Agitator, 47 ... Supply port, 50 ... Scanning unit, 51 ... Polygon mirror, 52 ... First scanning lens, 53 ... Second scanning lens, 54 ... Folding mirror, 55 ... Folding mirror, 60 Fixing unit 61 ... heating roller 62 ... pressure roller 70 ... paper discharge unit 71 ... paper discharge tray 72 ... inner guide member 73 ... outer guide member 74 ... discharge roller pair 101 ... cartridge housing, 101a ... left side, 101b ... right side, 102 ... gear mechanism, 103 ... developing roller drive gear, 104 ... feed roller drive gear, 105 ... input gear, 106 ... agitator drive gear, 107 ... idle gear, 111 ... toner cap 112 ... Reinforcing ribs, 113 ... Toner empty detection window, 120 ... Gear holder, 121a, 121b, 121c ... Support opening, 140 ... Dummy holder, 160 ... Biasing part, 161 ... Abutting part, 162 ... Slide support member, 163 ... Coiled spring, 180 ... Cartridge housing, 181 ... First housing part, 182 ... Second housing part, 18 ... the operated portion 186 ... support member, 190 ... urging member, 191 ... contact portion, 192 ... slide support member, 193 ... coil spring, 200 ... the acted portion.

Claims (11)

A developing cartridge that is detachably mounted on a photosensitive cartridge including a rotatable image carrier on which an electrostatic latent image is formed on an outer peripheral surface;
A rotatable developer-carrying member on which a developer is carried on the outer peripheral surface in order to develop and visualize the electrostatic latent image;
A first support plate that rotatably supports the developer carrier at one end in the axial direction of the developer carrier, and the developer carrier can be rotated at the other end in the axial direction of the developer carrier. A developing cartridge housing having a second support plate supported by
A transmission gear attached to the first support outer side opposite to the side on which the developer carrying member is disposed across the first support plate, and transmitting a rotational driving force to the developer carrying member;
A first covering member attached to the developing cartridge housing so as to cover the transmission gear on the outer side of the first support;
The development is performed so as to cover a surface of the second support plate on the outer side of the second support on the second support outer side opposite to the side on which the developer carrying member is disposed with the second support plate interposed therebetween. A second covering member attached to the cartridge housing;
The first covering member and the second covering member are selected from a plurality of types of biasing means set according to the toner type and roller material according to the toner type and roller material of the developing cartridge. First urging means that is attached to each of the members in a replaceable manner and applies a urging force so that the developer carrier presses the image carrier when the developer cartridge is attached to the photosensitive cartridge;
A developing cartridge comprising: The photosensitive cartridge includes an accommodating portion for accommodating the developing cartridge,
The first urging means is an urging member that generates the urging force by coming into contact with the accommodating portion when the developing cartridge is accommodated in the accommodating portion.
The developing cartridge according to claim 1. The biasing member is a spring;
The developing cartridge according to claim 2. The developing cartridge housing is separate from the first covering member and the second covering member.
The developing cartridge according to any one of claims 1 to 3, wherein The first covering member and the second covering member are detachably attached to the developing cartridge housing.
The developing cartridge according to claim 4. A rotatable developer carrier on which a developer is carried on the outer peripheral surface in order to develop and visualize the electrostatic latent image;
A photosensitive cartridge comprising: a rotatable image carrier on which an electrostatic latent image is formed on an outer peripheral surface; and a second urging unit for urging the developer carrier to the image carrier. A developing cartridge that is detachably mounted,
A first support plate that rotatably supports the developer carrier at one end in the axial direction of the developer carrier, and the developer carrier can be rotated at the other end in the axial direction of the developer carrier. A developing cartridge housing having a second support plate supported by
A transmission gear attached to the first support outer side opposite to the side on which the developer carrying member is disposed across the first support plate, and transmitting a rotational driving force to the developer carrying member;
A first covering member attached to the developing cartridge housing so as to cover the transmission gear on the outer side of the first support;
The development is performed so as to cover a surface of the second support plate on the outer side of the second support on the second support outer side opposite to the side on which the developer carrying member is disposed with the second support plate interposed therebetween. A second covering member attached to the cartridge housing;
Depending on the toner type and roller material of the developing cartridge, a plurality of types of affected parts in which the urging force of the second urging means changes by setting different positions depending on the toner type and roller material. It is selected, the first cover member and the replaceably attached to the respective second cover member, the developer cartridge forces acting force of the second biasing means when it is attached to the photosensitive member cartridge To be acted upon,
A developing cartridge comprising: The acting part is a projecting member projecting from each of the first covering member and the second covering member.
The developing cartridge according to claim 6. The developing cartridge housing is separate from the first covering member and the second covering member.
8. The developing cartridge according to claim 6, wherein the developing cartridge is characterized in that: The first covering member and the second covering member are detachably attached to the developing cartridge housing.
The developing cartridge according to claim 8. A developing cartridge according to any one of claims 1 to 5;
A photosensitive cartridge to which the developing cartridge according to claim 1 can be detachably mounted;
A process unit comprising: A developing cartridge according to any one of claims 6 to 9,
A rotatable image carrier on which an electrostatic latent image is formed on an outer peripheral surface is provided, and the developer cartridge according to any one of claims 6 to 9 can be detachably mounted, and development of the mounted developer cartridge is possible. A photosensitive member cartridge having a second urging means for urging the agent carrier to the image carrier;
A process unit comprising:

Images