JP7224919B2 - image forming device - Google Patents

Description

The present invention relates to an image forming apparatus equipped with a device for unsealing an opening of a developing device.

2. Description of the Related Art Conventionally, a developing device is provided in an image forming apparatus of an electrophotographic apparatus such as an electrophotographic copying machine, a laser beam printer, and a facsimile machine. The developing device has a developing chamber and a developer containing chamber. The developer containing chamber mainly contains the developer. The developing chamber mainly consists of a developing roller that is partially exposed and is placed in contact with the surface of the developing roller to maintain a constant amount of developer conveyed by the developing roller. A dosage control blade is provided. The developer adhering to the surface of the developing roller is conveyed from the portion of the developing roller exposed from the developing chamber to the developing area, which is the area adjacent to the photosensitive drum, which is the electrostatic latent image carrier, and formed on the photosensitive drum. Move onto the electrostatic latent image.
Here, the developing chamber and the developer containing chamber communicate with each other through an opening, and when the process cartridge is new, the opening is sealed by a sealing member as a sealing member. 2. Description of the Related Art Conventionally, a technique is known in which a seal member is peeled off from an opening in conjunction with the rotation of a rotating body such as a photosensitive drum.

For example, in the technique disclosed in Japanese Patent Application Laid-Open No. 2002-200000, in an image forming apparatus in which a plurality of process cartridges (units) are attachable and detachable, the driving force from the drive source is transmitted from the developing roller to the take-up shaft only in new process cartridges. is configured as Then, the driving force is transmitted to the winding shaft, thereby rotating the winding shaft and peeling off the sealing member sealing the opening. Further, in the technique disclosed in Patent Document 2, the rotation of the unsealing member peels off the sealing member that seals the opening.

JP 2006-184546 A JP 2014-016544 A

In recent years, with the demand for cost reduction and miniaturization of devices, it is necessary to reduce the number of motors that serve as drive sources and to miniaturize the motors themselves. The smaller the maximum drivable torque of the motor that serves as the drive source, the easier it is to reduce the number of motors and reduce the size. However, if the specifications of the motor in the device are set such that the maximum torque that can be driven does not have a margin with respect to the required driving force, the following problems may occur.

For example, when the developer is unevenly distributed in the developer storage chamber during transportation, more torque than expected may be required to open the seal member that seals the opening. That is, when vibration or the like is applied to the developer in a biased state in the developer storage chamber, the developer is compacted (agglomerated), the density per unit volume increases, and the developer is compacted powder. More force must be applied to loosen the Therefore, in a structure in which the rotating shaft of the stirring member also serves as the opening member of the sealing member, the stirring member transports the developer while loosening it, so the torque required to drive the stirring member increases. In such a process cartridge, when the sealing members are opened simultaneously for a plurality of process cartridges, the torque required for the sealing members to be opened exceeds the maximum drivable torque. There is concern that the unsealing operation will not be possible. Therefore, in light of such concerns, it is required to reduce the number of motors that serve as drive sources and to promote miniaturization of the motors themselves.

SUMMARY OF THE INVENTION An object of the present invention is to facilitate response to demands for miniaturization/common use of drive sources.

In order to achieve the above object, the image forming apparatus of the present invention includes:
An image forming apparatus having a plurality of image forming units for each color of developer that forms a developer image by developing an electrostatic latent image formed on an image carrier with the developer carried by the developer carrier. There is
a device body;
(i) a first unit detachable from the apparatus main body and rotatably supporting the image carrier; and (ii) detachable from the apparatus main body and capable of rotating the developer carrier. an accommodating portion for accommodating the developer , an agitating member for rotating and agitating the developer accommodated in the accommodating portion, and a sealing member for sealing the opening of the accommodating portion in an unused state, and the sealing member that is provided on the rotation shaft of the stirring member and is wound up by rotation of the rotation shaft so that the opening is opened. ,
a driving unit having a motor and configured to transmit a rotational driving force of the motor to the plurality of image forming units;
drive detection means for detecting an operating state of the motor;
with
In a winding operation for winding the seal member by rotating the rotating shaft when the unused second unit is attached to the apparatus main body,
(A) driving the motor so that the rotational driving force can be transmitted to all of the plurality of image forming units;
(B) When the drive detection means detects that the motor is operating or is operating under a predetermined condition, all of the plurality of second units simultaneously rotate the rotating shafts . ,
(C) When the drive detection means does not detect that the motor is operating or that the motor is operating under a predetermined condition, the number of the second units that simultaneously rotate the rotating shaft is and rotating the rotating shaft sequentially in a plurality of the second units so as to be smaller than the total number of the plurality of the second units.

ADVANTAGE OF THE INVENTION According to this invention, the request|requirement of size reduction / sharing of a drive source can be accelerated|stimulated.

Schematic cross-sectional view of an image forming apparatus according to an embodiment Appearance perspective view of the drum cartridge in the embodiment Sectional view of the drum cartridge in the embodiment Sectional view of the drum cartridge in the embodiment Appearance perspective view of the developing cartridge in the embodiment Sectional view of the developer cartridge in the embodiment Schematic diagram of the drive train of the drive motors related to the toner seal opening operation in the embodiment. Explanatory drawing of the clutch mechanism in the embodiment Explanatory drawing of Oldham in the example Control Block Diagram of Image Forming Apparatus in Embodiment Explanatory drawing of toner unsealing means in the embodiment Flowchart 1 for Example 1 Flowchart 2 for Example 2 Timing chart of development contact/separation and drive transmission to stirring member in the embodiment

Embodiments or examples of the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, relative positions, and the like of the components described in the embodiment or example may be changed as appropriate depending on the configuration of the device to which the invention is applied and various conditions, and therefore may not be particularly specific. Unless otherwise stated, they are not intended to limit the scope of the invention only to them.
Unless otherwise specified, the term "above" in the following description indicates the upper direction in the gravitational direction when the image forming apparatus is installed on a horizontal installation surface as a normally assumed installation state.

(Example 1)
An image forming apparatus according to an embodiment of the present invention is a full-color laser printer that employs a so-called in-line method and an intermediate transfer method. An image forming apparatus can form a full-color image on a recording material (for example, recording paper, plastic sheet, cloth, etc.) according to image information.
Examples of image forming apparatuses include copiers, printers (laser beam printers, LED printers, etc.), facsimile machines, word processors, and multifunction machines (multifunction printers).
Image information is input to the image forming apparatus from an image reading device connected to the image forming apparatus main body or a host device such as a personal computer communicably connected to the image forming apparatus main body.

Further, the cartridge (unit) refers to a component of the image forming apparatus that is detachable from the main body of the image forming apparatus. Examples thereof include a drum cartridge (drum unit) having a photosensitive drum and a developing cartridge (developing unit) acting on the drum cartridge having an electrostatic latent image to form a toner image.

In the following embodiments, the image forming apparatus includes (i) four drum cartridges (first unit) and (ii) four developing cartridges (second unit), that is, four detachable process cartridges. A full-color laser printer is illustrated. In other words, a plurality of image forming units are provided for each toner color. The number of cartridges to be mounted on the image forming apparatus is not limited to this.

<Overview of Electrophotographic Image Forming Apparatus>
First, the overall configuration of an electrophotographic image forming apparatus (image forming apparatus) according to this embodiment will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view of an image forming apparatus 200 of this embodiment.

As shown in FIG. 1, the image forming apparatus 200 has a plurality of image forming units, each of which forms an image of each color of yellow (Y), magenta (M), cyan (C), and black (K). 1, 2nd, 3rd and 4th image forming units SY, SM, SC and SK. In this embodiment, the first to fourth image forming units SY, SM, SC, and SK are arranged in a line substantially horizontally. In this embodiment, the drum cartridges 213 (213Y, 213M, 213C, 213K) and the developing cartridges 204 (204Y, 204M, 204C, 204K) are practically configured and operated except that the colors of the formed images are different. is the same as Therefore, in the following description, Y, M, C, and K will be omitted unless they need to be distinguished from each other, and a general description will be given.

In this embodiment, the image forming apparatus 200 has, as a plurality of image carriers, cylinders (hereinafter referred to as photoconductor drums) 1 having four photosensitive layers arranged side by side in a direction slightly inclined with respect to the vertical direction. .
A scanner unit (exposure device) 3 is arranged below the drum cartridge 213 and the developing cartridge 204 in the direction of gravity. Further, around the photosensitive drum 1, a charging roller 2 and the like are arranged as process means acting on the photosensitive layer. The charging roller 2 is charging means (charging device, charging member) that uniformly charges the surface of the photosensitive drum 1 . After that, the photosensitive drum 1 receives exposure corresponding to print information and image information by a scanner unit 3, which is exposure means (exposure device, exposure member).

A cleaning blade 6 as cleaning means (cleaning device, cleaning member) and a developing cartridge 204 are arranged around the photosensitive drum 1 . Also, an intermediate transfer belt serving as an intermediate transfer member for transferring the toner image (developer image) on the photosensitive drum 1 onto a recording material (sheet, recording medium) 12 facing the four photosensitive drums 1 5 are placed. The developer cartridge 204 of this embodiment uses a non-magnetic one-component developer (hereinafter referred to as toner) as a developer for developing an electrostatic latent image (latent image) on the photosensitive drum 1, and serves as a developer carrier. A contact developing method is employed in which the developing roller 217 is brought into contact with the photosensitive drum 1 .

In the above configuration, the toner image formed on the photosensitive drum 1 is transferred onto the recording material 12 via the intermediate transfer belt 5, and the toner image transferred onto the recording material 12 is fixed. Further, the toner remaining on the photosensitive drum 1 without being transferred onto the intermediate transfer belt 5 is collected by the cleaning blade 6 . Further, the transfer residual toner collected by the cleaning blade 6 is stored in the waste toner storage section 214a through the opening 214b (see FIG. 4). The waste toner container 214 a and the cleaning blade 6 are integrated to form a drum cartridge 213 .

The image forming apparatus 200 also includes guides (positioning means) such as a mounting guide and a positioning member (not shown) on the body frame. The developing cartridge 204 and the drum cartridge 213 are guided by the guides described above, and are detachable from the image forming apparatus main body 200 . Incidentally, the developing cartridge 204 and the drum cartridge 213 can also be handled integrally as the process cartridge 207 .

The developing cartridges 204 for respective colors contain toners of yellow (Y), magenta (M), cyan (C), and black (K), respectively. The intermediate transfer belt 5 contacts the photosensitive drums 1 of the drum cartridges 213 and rotates (moves) in the direction of arrow B in FIG. The intermediate transfer belt 5 is stretched over a plurality of supporting member driving rollers 51 , secondary transfer facing rollers 52 and driven rollers 53 . Four primary transfer rollers 8 as primary transfer means are arranged side by side on the inner peripheral surface side of the intermediate transfer belt 5 so as to face each photosensitive drum 1 . A secondary transfer roller 9 as a secondary transfer means is arranged at a position facing the secondary transfer opposing roller 52 on the outer peripheral surface side of the intermediate transfer belt 5 .

An image forming method will be described with reference to FIG. First, the charging roller 2 is pressed against the photosensitive drum 1 by a supporting member (not shown), and is rotated by the rotation of the photosensitive drum 1 . The charging roller 2 is charged to Vd (-500 V) by a bias (-1 KV) to which a charging bias is applied from a charging bias power supply (not shown) within the main body of the image forming apparatus. The outer diameters of the photosensitive drum 1 and charging roller 2 in this embodiment are 30 mm and 11 mm, respectively. Subsequently, the surface of the charged photosensitive drum 1 is scanned and exposed by laser light emitted from the scanner unit 3 according to image information. As a result, an electrostatic latent image is formed on the photosensitive drum 1 according to the image information. Note that the potential of the exposed portion becomes VL (-100 V). The electrostatic latent image formed on the photosensitive drum 1 is developed as a toner image by the developer cartridge 204 . The toner image formed on the photosensitive drum 1 is transferred (primary transfer) onto the intermediate transfer belt 5 by the action of the primary transfer roller 8 .

For example, when forming a full-color image, the above-described process is sequentially performed in the four drum cartridges 213 (213Y, 213M, 213C, 213K) and developer cartridges 204 (204Y, 204M, 204C, 204K). Then, toner images of respective colors formed on the photosensitive drums 1 of the drum cartridges 213 are sequentially primary-transferred so as to be superimposed on the intermediate transfer belt 5 . After that, the recording material 12 is conveyed to the secondary transfer portion in synchronization with the movement of the intermediate transfer belt 5 . Then, the four-color toner images on the intermediate transfer belt 5 are collectively transferred onto the recording material 12 conveyed to the secondary transfer portion formed by the intermediate transfer belt 5 and the secondary transfer roller 9 .

The recording material 12 onto which the toner image has been transferred is conveyed to a fixing device 10 as fixing means. The toner image is fixed on the recording material 12 by applying heat and pressure to the recording material 12 in the fixing 10 . Further, primary transfer residual toner remaining on the photosensitive drum 1 after the primary transfer process is removed by the cleaning blade 6 and collected as waste toner. Secondary transfer residual toner remaining on the intermediate transfer belt 5 after the secondary transfer process is removed by the intermediate transfer belt cleaning device 11 .
Note that the image forming apparatus 200 is also capable of forming monochromatic or multicolor images using a desired single or some (but not all) image forming units.

<Outline of Drum Cartridge and Developing Cartridge>
2 to 6, outlines of the drum cartridges 213 (213Y, 213M, 213C, 213K) and the developing cartridges 203 (204Y, 204M, 204C, 204K) mounted in the image forming apparatus main body 200 shown in FIG. will be explained.

The drum cartridge 213Y, the drum cartridge 213M, the drum cartridge 213C, and the drum cartridge 213K have the same configuration. The developer cartridge 204Y containing yellow toner, the developer cartridge 204M containing magenta toner, the developer cartridge 204C containing cyan toner, and the developer cartridge 204K containing black toner have the same configuration except for the toner. Therefore, in the following description, the drum cartridges 213Y, 213M, 213C, and 213K are collectively referred to as the drum cartridge 213, and the developing cartridges 204Y, 204M, 204C, and 204K are collectively referred to as the developing cartridge 204. Each cartridge constituent member will also be generically described in the same way.

2 is an external perspective view of the drum cartridge 213. FIG. Here, as shown in FIG. 2, the rotation axis direction of the photosensitive drum 1 is the Z axis (arrows Z1 and Z2), the horizontal direction in FIG. 2 is the X axis (arrows X1 and X2), and the vertical direction in FIG. is the Y-axis (arrow Y1, arrow Y2), and the three are orthogonal to each other. FIG. 3 is a cross-sectional view of a virtual plane on which the rotation center of the photosensitive drum 1 of the drum cartridge 213 is aligned. The side (downstream side in the Z1 direction) where the portion (coupling member 228) that receives the driving force from the main body of the image forming apparatus is arranged is called the driving side (back side) of the drum cartridge 213 . The side opposite to the driving side (downstream side in the Z2 direction) is called the non-driving side (front side) of the drum cartridge 213 .

At the end opposite to the coupling member 228 (the non-driving end of the drum cartridge), there is an electrode (electrode portion) that contacts the inner surface of the photosensitive drum 1 , and this electrode contacts the image forming main body 200 . By doing so, it plays a role of earth.

A coupling member 228 is attached to one end of the photoreceptor drum 1 and a non-driving side flange member 229 is attached to the other end of the photoreceptor drum 1 to form a photoreceptor drum unit 230 . The photosensitive drum unit 230 receives driving force from a drive shaft 201 provided in the image forming main body 200 via a coupling member 228 . This coupling member 228 is connected to the drive shaft 2
01 so as to be connectable and detachable.

As shown in FIG. 3, the Z1-axis downstream side of the coupling member 228 has a cylindrical shape (cylindrical portion 271). The cylindrical portion 271 protrudes from the end portion of the photosensitive drum 1 to the Z1 axis downstream side (outward in the axial direction). The outer peripheral portion of the cylindrical portion 271 is an outer peripheral surface 271a. The outer peripheral surface 271a is rotatably supported by the drum unit bearing member 239R.

Similarly, a non-driving side flange member 2229 provided on the non-driving side of the photosensitive drum unit 230 is rotatably supported by the drum unit bearing member 239L. The non-driving side flange member 229 has a cylindrical portion (cylindrical portion) protruding from the end of the photosensitive drum 1, and the outer peripheral surface 229a of this cylindrical portion is rotatably supported by the drum unit bearing member 239L.

When the drum cartridge 213 is attached to the image forming apparatus main body 200 , the drum unit bearing member 239</b>R abuts against a rear cartridge positioning portion (not shown) provided on the image forming apparatus main body 200 . Also, the drum unit bearing member 239L abuts against the front side cartridge positioning portion (not shown) of the image forming apparatus main body 200 . Thereby, the drum cartridge 213 is positioned in the image forming apparatus main body 200 .

As described above, the drum unit bearing members 239 (239R, 239L) are attached to both sides of the cleaning frame 214 and support the photosensitive drum unit 230 respectively. As a result, the photosensitive drum unit 230 is rotatably supported by the cleaning frame 214 . Also, the charging roller 2 and the cleaning blade 6 are attached to the cleaning frame 214 , and are arranged so as to contact the surface of the photosensitive drum 1 . Also, the charging roller bearing 15 is attached to the cleaning frame 214 (see FIG. 4). The charging roller bearing 15 is a bearing for supporting the shaft 2 a of the charging roller 2 .

Here, the charging roller bearing 15 is attached so as to be movable in the direction of arrow C shown in FIG. A rotating shaft 2 a of the charging roller 2 is rotatably attached to a charging roller bearing 15 . The charging roller bearing 15 is urged toward the photosensitive drum 1 by a pressure spring 16 as urging means. As a result, the charging roller 2 abuts against the photosensitive drum 1 and rotates following the photosensitive drum 1 rotating in the direction of the arrow A. As shown in FIG.

The cleaning frame 214 is provided with a cleaning blade 6 as cleaning means for removing toner remaining on the surface of the photosensitive drum 1 . The cleaning blade 6 includes a plate-like elastic member 6a that contacts the photosensitive drum 1 and removes the toner on the photosensitive drum 1 by sliding contact with the rotating photosensitive drum 1, and a support sheet metal 6b that supports it. , are integrated. In this embodiment, the plate-like elastic body 6a of the cleaning blade 6 is made of urethane rubber having a thickness of 2 mm and an MD-1 hardness of 60 to 80° under an environment of 23°C. The support plate 6b is attached to the cleaning frame 214 by screwing.

As described above, the cleaning frame 214 has an opening 214 b for collecting the transfer residual toner collected by the cleaning 6 . The opening 214b is provided with a blowout prevention sheet 26 that abuts against the photosensitive drum 1 and seals the gap between the photosensitive drum 1 and the opening 214b to prevent toner leakage upward from the opening 214b.

Further, the drum cartridge 213 is provided with a nonvolatile memory (hereinafter referred to as O memory m1). The 0 memory mm1 stores information such as whether or not the drum cartridge is new (unused), the number of rotations of the photosensitive drum 1, and the manufacturing number. , the usage amount of the drum cartridge 213 can be grasped. Note that the 0 memory m1 is configured to be capable of communicating (writing and reading information) with the controller 300 of the image forming apparatus 200 shown in FIG.

FIG. 5 is an external perspective view of the developer cartridge 204. As shown in FIG. FIG. 6 is a schematic cross-sectional view of the developer cartridge 204. As shown in FIG. The developer cartridge 204 has a developer frame 218 that supports various elements. The developing cartridge 204 is provided with a developing roller 217 as a developer carrying member that contacts the photosensitive drum 1 and rotates in the direction of arrow D (counterclockwise) as shown in FIG. The developing roller 217 is rotatably supported by the developing frame 218 via developing bearings 219 (219R, 219L) at both ends in the longitudinal direction (rotational axis direction). Here, the developing device bearings 219 (219R, 219L) are attached to both ends of the developing device frame 218, respectively. Further, as shown in FIG. 6, the developer cartridge 204 has a developer storage chamber (hereinafter referred to as toner storage chamber) 218a as a toner storage portion, and a development chamber 218b in which a development roller 217 is disposed. The toner storage chamber 218a and the development chamber 218b communicate with each other through an opening 218c.

In the developing chamber 218b, there are provided a toner supply roller 220 as a developer supplying member that contacts the developing roller 217 and rotates in the direction of arrow E, and a developing roller 220 as a developer amount regulating member for regulating the toner layer of the developing roller 217. A blade 221 is arranged. The developing blade 221 is fixed and integrated with the fixing member 222 by welding or the like. The outer diameters of the developing roller 217 and the toner supply roller 220 in this embodiment are 16 mm and 18 mm, respectively.
The developing blade 221 is a plate spring made of SUS and contacts the developing roller 217 with a predetermined contact pressure.

The toner storage chamber 218a has a stirring member 223 for stirring and conveying toner. The stirring member 223 is composed of a stirring sheet 223a and a stirring shaft 223b. One end of the stirring sheet 223a is attached to the stirring shaft 223b, and when the stirring shaft 223b rotates in the arrow F direction, the stirring sheet 223a also rotates. The toner in the toner storage chamber 218a is stirred by the rotation of the stirring sheet 223a, and the toner is pumped up and transported from the toner storage chamber 218a to the developing chamber 218b through the opening 218c. In this embodiment, the stirring sheet 223a is a flexible sheet member. The rotation speed of the stirring member 223 is 60 rpm during normal printing operations.

The toner conveyed from the toner containing chamber 218 a to the developing chamber 218 b by the stirring member 223 is conveyed to the developing roller 217 by the toner supply roller 220 . Frictional electrification is applied to the developing roller 217 by the developing blade 221, and the layer thickness of the toner layer on the developing roller 217 is regulated. The toner on the developing roller 217 is appropriately charged and conveyed to the developing area on the photosensitive drum 1 . The electrostatic latent image on the photosensitive drum 1 is developed at the contact portion between the photosensitive drum 1 and the developing roller 217 . In this embodiment, the rotational speeds of the photosensitive drum 1 and the developing roller 217 during normal printing operations are 190 mm/sec and 250 mm/sec, respectively, and the peripheral speed ratio of the developing roller 217 to the photosensitive drum 1 is 131%. That is, at the contact portion between the photosensitive drum 1 and the developing roller 217 that move in the same direction, the developing roller 217 and the photosensitive drum 217 are arranged so that the circumferential surface of the developing roller 217 moves faster than the circumferential surface of the photosensitive drum 1 . The rotation speed of the body drum 1 is set.

Further, the developing cartridge 204 is provided with a nonvolatile memory (hereinafter referred to as D memory m2). The D memory m2 stores information such as whether or not the developing cartridge 204 is new, the number of rotations of the developing roller 217, the remaining amount of toner, and the manufacturing number. , the usage amount of the developing cartridge 204 can be grasped. The D memory m2 is configured to be able to communicate (write and read information) with the controller 300 of the image forming apparatus 200 shown in FIG.

In this embodiment, the driving force is transmitted to the developing cartridge 204 when the developing cartridge 204 is in contact with the drum cartridge 213 . That is, when the operation of rotating the developing roller 217 is performed, the operation of bringing the developing roller 217 into contact with the photosensitive drum 1 is performed at the same time. Further, when the operation of stopping the rotation of the developing roller 217 is performed, the operation of separating the developing roller 217 from the photosensitive drum 1 is performed at the same time. By simultaneously performing the contact and separation operations between the developing roller 217 and the photosensitive drum 1, the rotation time of the developing roller per image formation can be shortened as much as possible. In other words, rather than performing the separate operations of rotating the developing roller 217 in the separated state and then performing the abutting operation of the developing roller 217 and the photosensitive drum 1, by simultaneously performing the two operations, The rotation time of the developing roller 217 can be shortened. This makes it possible to prevent deterioration in durability of the developing cartridge 204 as much as possible.

Further, in this embodiment, since the yellow (Y), magenta (M), and cyan (C) drum cartridges 213 are driven by a common motor, yellow (Y), magenta (M), and cyan (C) , the photosensitive drums cannot be driven independently. On the other hand, although the motors for driving the yellow (Y), magenta (M), and cyan (C) developing cartridges 204 are common, they are driven only when the developing roller 217 and the photosensitive drum 1 are in contact with each other. Therefore, the developing cartridge 204 can be driven independently.

<Contact and Separation Mechanism Between Photoreceptor Drum and Developing Roller>
<Drive Mechanism from Drive Motor M to Stirring Member 223>
A drive mechanism from the drive motor M to the stirring member 223 in this embodiment will be described.
There are three main mechanisms: a drive motor M, a clutch mechanism, and a coupling mechanism that is a driving force transmitting portion between the image forming apparatus main body 200 and the process cartridge 207 .
Four drive motors M are arranged to drive the process cartridges 207 . That is, a driving motor M1 for driving the YMC developing cartridge 204, a driving motor M2 (not shown) for driving the YMC drum cartridge 213, a driving motor M3 for driving the K drum cartridge 213, the developing cartridge 204, and the fixing device 10 ( (not shown), and a development contact/separation motor M4 for controlling the contact/separation operation between the photosensitive drum and the developing roller.

FIG. 7 is a schematic diagram showing the drive train of the drive motors M1 and M4 involved in the toner seal opening operation. It should be noted that illustration of gears is omitted for some gears. The driving force of the drive motor M1 is transmitted from the pinion gear 420 provided on the output shaft of the drive motor M1 to the clutch Y403 via the large gear a401. The driving force received by the clutch Y403 is transmitted to the coupling mechanism Y406 via gears when the clutch is ON. The driving force transmitted to the coupling mechanism Y406 is transmitted to the toner supply roller 220 via the Oldham Y415 and an Oldham coupling, which will be described later. The driving force transmitted to the toner supply roller 220 is further transmitted to the Y developing cartridge 204Y and the stirring member 223 via gears (not shown). Regarding the developing cartridges 204M and 204C of MC, the driving force is transmitted to the clutch M403 via the large gear a401, and the driving force of the clutch C403 is transmitted via the large gear a401, the clutch M403, and the large gear b402. When the clutches of the clutches M403 and C403 are ON, the driving force is transmitted to the coupling mechanisms M406 and C406, and toner is supplied to the developing cartridges 204M and 204C via the Oldham M415 and C415 and each Oldham coupling described later. The roller 220, toner supply roller 220, and stirring member 223 are driven. This is the same as the developer cartridge 204Y. The K developing cartridge 204K has the same configuration as the developing cartridge 204Y except that the drive source is the driving motor M3.
As shown in FIG. 7, a rotating shaft 411 connected to the output shaft of the development contact/separation motor M4 rotates through worm gears Y414, M414, and C414 to develop contact/separation gears Y413, M413, and C413, which are step gears. They are connected to each other so as to be able to transmit driving force. The development contact/separation gears Y413, M413 and C413 are provided with cams Y416, M416 and C416, respectively. The cams Y416, M416, and C416 rotate the contact/separation gears Y413, M413, and C413 to apply contact/separation force receiving portions 226 (see FIG. 6) provided to the developing frames 218 of the developing cartridges 204Y, 204M, and 204C. ) can be directly or indirectly contacted and separated from each other. Each of the cams Y416, M416, and C416 directly or indirectly abuts on the contact/separation force receiving portion 226 of each developing frame, so that the force W in FIG. Then, the photosensitive drum and the developing roller are separated from each other in each image forming section. Further, since the force W no longer acts on the contact/separation force receiving portion 226, the photosensitive drum and the developing roller are separated from each other. The rotation phases of the cams Y416, M416, and C416 are set so that the contact timing of the photosensitive drum and the developing roller in each image forming unit is in the order of Y, M, and C. This situation is shown in the timing chart of FIG.

<Clutch mechanism>
ON/OFF of the clutches Y403, M403 and C403 is controlled by the operation of the development contact/separation motor M4 in synchronization with the above-described cams Y416, M416 and C416 for contacting and separating the photosensitive drum and the developing roller.
Since the clutch mechanism has the same configuration for each color, Y will be described using FIGS. 8(a), 8(b), and 8(c).
FIG. 8(a) is a perspective view of the clutch Y403, FIG. 8(b) is a perspective view of gears forming the clutch Y403, and FIG. 8(c) is a cross-sectional view when the clutch is ON and OFF.
The clutch Y403 is composed of a clutch gear a407, a coupling gear b408, a clutch control section 410, and a clutch gear c409.
The driving force transmitted from the driving motor M1 is input to the clutch gear c409.
The clutch gear c409 is pressed upward in FIG. 8(b) by a spring (not shown), and is connected to the cup below the clutch gear a407 in the figure via a coupling portion 419 also upward in the figure. A driving force is transmitted to the ring portion 417 to drive the clutch gear a407. The clutch gear a407 transmits driving force to an Oldham Y415, which will be described later, via gears.

When the drive transmission is turned off, first, the rotary shaft 411 shown in FIG. 7 is rotated by being driven by the development contact/separation motor M4. A development contact/separation gear Y413 with a cam Y416 is rotated via a worm gear Y416. The development contact/separation gear Y413 transmits drive to the connection gear b408 in FIG. 8(b). Then, the convex portion 418a arranged below the coupling gear b408 in the drawing rotates along the guide portion 405a of the clutch gear control portion 410, and depending on the phase (according to the height of the guide portion 405a), the clutch gear c409 is pushed downward in the figure. In addition, the convex portion 418b arranged below the connecting gear b408 in the drawing rotates along the guide portion 405b of the clutch gear control portion 410, and depending on the phase (according to the height of the guide portion 405b), the clutch gear c409 is pushed downward in the figure. Here, the downward depression of the guide portion 405a by the convex portion 418a and the downward depression of the guide portion 405b by the convex portion 418b occur simultaneously. As a result, the clutch gear c409 is smoothly pushed downward.
The tip surface of the projection 418a protruding toward the clutch gear control portion 410 (downward in FIG. 8) abuts the tip surface of the guide portion 405a that projects oppositely (upward in FIG. 8). in contact with The guide portion 405 is configured such that the protrusion height of its tip end surface changes in the relative rotation direction of the coupling gear b408 and the clutch gear control portion 410 . By moving the convex portion 418a along the distal end surface of the guide portion 405 in the circumferential direction around the rotation axis, the connection gear b40
8 and clutch gear control unit 410 move relative to each other along the rotation axis direction. The clutch gear a407 is integrated with the coupling gear b408, and the clutch gear c409 is integrated with the clutch gear control section 410, and displaced along the rotation axis direction. As a result, the coupling portion 419 of the clutch gear c409 and the coupling portion 417 of the clutch gear a407 are separated from each other, and drive transmission is turned off.

FIG. 8(c) is a cross-sectional view when the clutch is ON and OFF. When ON, the coupling portion 419 of the clutch gear c409 and the coupling portion 417 of the clutch gear a407 are engaged, and the driving force of the driving motor M1 is transmitted to the developing roller 217, the toner supply roller 220, and the stirring member 223. state. When OFF, as described above, the clutch control unit 410 and the clutch gear c409 are pushed downward, the coupling between the clutch gear c409 and the clutch gear a407 is separated, and the driving force of the driving motor M1 is applied to the developing roller 217, It is in a state where it is not transmitted to the toner supply roller 220 and the stirring member 223 .

By operating the development contact/separation motor M4 by the control unit 300 according to a control flow described later, the development contact/separation and drive transmission to the stirring member 223 can be controlled integrally. That is, the stirring member 223 is stopped when the developer is separated from the developer, and is driven when the developer is in contact with the developer, so that the seal opening operation can be started.

<Coupling mechanism>
The rotation axis of the Oldham Y415 is as shown in FIGS. 9(a) and 9(b).
The main body drive shaft 4101 is composed of a gear member 4101e, an intermediate member 4101p, an output member 4101q, and a drive transmission member 4101r. The gear member 4101e receives rotational drive from the drive motor M1 through gears, and the drive is transmitted to the intermediate member 4101p, the output member 4101q, and the drive transmission member 4101r in this order, and the main body drive shaft 4101 rotates. Further, the gear member 4101e, the intermediate body 4101p, and the output member 4101q have an Oldham's joint mechanism, and can move a certain distance in the X direction and the Y direction. Therefore, the drive transmission member 4101r provided on the cartridge side of the main body drive shaft 4101 via the Oldham's coupling can also move a certain distance in the X direction and the Y direction, for example, contact and separation operations. The drive transmission member 4101r has a rotatable shaft portion 4101f, and the rotational driving force received from the driving motor M1 is transmitted to the developing cartridge 207 through a groove-shaped drive transmission groove 4101a provided in the shaft portion 4101f. The toner is transmitted to the toner supply roller 220 and the stirring member 223 that are arranged.

<Block diagram>
A control configuration of the image forming apparatus 200 will be described with reference to FIG. FIG. 10 is a control block diagram of the image forming apparatus 200. As shown in FIG.
The control unit 300 includes a CPU (Central Processing Unit) 301 which is a central element that performs arithmetic processing, a memory 302 such as an R0M and a RAM as storage means, and an input/output I/F 303 for inputting/outputting information with peripheral devices. etc. The RAM stores sensor detection results, calculation results, and the like, and the ROM stores control programs, pre-determined data tables, and the like. The control unit 300 is control means for comprehensively controlling the operation of the image forming apparatus 200 , and each control target in the image forming apparatus 200 is connected via an input/output I/F 303 . The control unit 300 controls the transmission and reception of various electrical information signals, the timing of driving, and the like, and manages flowchart processing and the like to be described later.

A motor drive unit 304 indicates various motors including drive motors M1 and M2, and is a drive source for rotationally driving a positon scanner (not shown), the photosensitive drum 1, the developing roller 217, and the like. It operates based on control signals. A high-voltage power supply 305 is a power supply that applies a high voltage to the photosensitive drum 1, the charging roller 2, the developing roller 217, the primary transfer roller 8, the secondary transfer roller 9, the fixing device 10, and the like. Also, the control unit 300, the 0 memory m1 and the D memory m
2, data communication is performed via the memory communication unit 306 . The control unit 300, the D memory m2, the memory communication unit 306, and the like constitute new product detection means for detecting whether or not the developing cartridge 204 is new (unused). Further, an environment sensor 307 such as a temperature and humidity sensor is connected to the control unit 300 .

In this embodiment, whether or not the drum cartridge 213 and developing cartridge 204 are new is also detected based on the data read from the 0 memory m1 and the D memory m2.

<Toner Seal Opening Means>
The toner seal opening means will be described with reference to FIG.
FIG. 11A is a sectional view showing the state of the toner seal 275 when the developing cartridge 204 is new. FIG. 11B is a cross-sectional view showing a state in which the stirring member 223 is driven and the toner seal 275 is being unsealed. FIG. 11(c) is a sectional view showing a state in which the operation of opening the toner seal 275 is completed.

When the developing cartridge 204 is new, it is necessary to prevent toner from leaking out of the developing cartridge 204 while it is delivered from the manufacturer to the user.
Therefore, in order to seal the opening 218c between the toner containing chamber 218a containing the toner and the developing chamber 218b containing the developing roller 217, the toner seal 275 seals the opening 218c. One end of the toner seal 275 is fixed so as to seal the opening 218 c of the developing frame 218 , and the other end is fixed to the stirring member 223 . A toner seal 275 is held between the folding portion 224 and the stirring member 223 by the unsealing assisting member 225 .

When the user uses the cartridge, the drive from the main body is transmitted to the stirring shaft 223b, and the stirring member 223 inside the toner storage chamber 218a rotates (H direction) through the driving of the stirring shaft 223b. is removed from the opening 218c. By peeling off the toner seal 275 from the opening 218c, the toner can be transported from the toner containing chamber 218a to the developing chamber 218b.

The developing frame 218 and the opening 218c used in the embodiment of the present invention are made of a material that is not greatly deformed by the force of peeling off the toner seal 275 and the position of the opening 218c is not changed. Uses resin.

Here, the toner seal 275 is folded back inside the toner storage chamber 218a and fixed to the opening 218c (folded portion 224) so that the toner seal 275 can be easily peeled off from the opening 218c. The fixing method of the toner seal 275 to the opening 218c uses a heat sealing method such as thermal welding, but a fixing method such as ultrasonic welding or double-sided tape may also be used.

<Flowchart 1>
12 and the timing chart of FIG. 14, the toner seal opening operation when the developing cartridge 204 is detected to be new in this embodiment will be described. Note that this flowchart is executed by the control unit 300 .

When the developing cartridge 204 is attached to the image forming apparatus 200 (S501), data communication is performed between the control section 300 and the D memory m2 via the memory communication section 306 (S502). Through data communication, the control unit 300 acquires the information of the new product flag (for example, if 0, the product is new, and if it is 1, the product is in use) from the D memory m2. Based on the acquired information, the control unit 300
It is determined whether or not there is a new developing cartridge 204 attached (S503).

If it is determined that the installed developer cartridge 204 is not new, the controller 300 terminates the process because the toner seal opening operation is not required (S509). If it is determined that the attached developing cartridges 204 are new, it is determined whether or not the attached developing cartridges 204 other than the black (K) developing cartridge 204 are new (S504). .

When it is determined that the developing cartridge 204 other than the black (K) developing cartridge 204 is not new, the control section 3300 controls the drive motor M3 for rotating the black (K) stirring member 223, and executes the black toner seal opening operation. (S505). After that, the process ends (S509). If it is determined that there is a new cartridge other than the black (K) developing cartridge 204, the simultaneous all-color toner seal opening operation determination means determines whether or not the simultaneous all-color toner seal opening operation can be executed. (S506). Describing the process of step S506 in more detail, the control unit 300 drives the drive motor M1 to operate the drive train described with reference to FIG. 7 operates, the ON/OFF state of each clutch 403 and the contact/separation state between the photosensitive drum 1 and the developing roller 217 transition as shown in the timing chart of FIG.
In the timing chart of FIG. 14, the rotation phase of the cam Y416 of the Y developing cartridge 204 is used as a reference to determine the timing of contact between the photosensitive drum and the developing roller in each of the Y, M, and C image forming portions and the ON/OFF of the clutch. shows the timing of As described above, the contact timing of the photosensitive drum and the developing roller in each image forming section and the ON timing of the clutch are arranged in the order of Y, M, and C. As shown in FIG. Therefore, as shown in FIG. 14, the photosensitive drum and the developing roller are in contact with each other in all the Y, M, and C image forming portions, and the driving force is transmitted to the developing roller (clutch ON) at phase P1. , it is determined whether or not the simultaneous toner seal opening operation for all colors can be executed. Details of determination by the control unit 300 as to whether or not the simultaneous toner seal opening operation for all colors can be executed will be described later.

If it is determined that the all-color toner seal opening operation can be performed, the all-color simultaneous toner seal opening operation is performed (S508), and then the process ends (S509). If it is determined that the simultaneous toner seal opening operation for all colors cannot be executed, the toner seal pulling operation is sequentially executed (S507), and then the process ends (S509).
The sequential toner seal pulling operation will be described with reference to FIG. For example, first, the development contact/separation motor M4 forwardly rotates the rotary shaft 411 until phase P2-1, and the toner seal of the Y development cartridge is unsealed. Next, the rotary shaft 411 is reversely rotated to phase P2-2, and the toner seal of the developing cartridge C is unsealed. Finally, the rotary shaft 411 is reversely rotated to phase P2-3 to unseal the toner seal of the M developer cartridge. In phase P2-3, the developing cartridge C is also in a driven state, but since the toner seal has been peeled off, the torque required for driving is smaller than during the unsealing operation, and the toner seal unsealing operation of the developing cartridge M is performed. have little impact on The drive control of the development contact/separation motor M4 is performed by the control unit 300, and the same applies hereinafter.
Alternatively, after unsealing the toner seal of the Y developing cartridge at phase P2-1, the rotation shaft 411 may be further rotated forward to unseal the toner seal of the M developing cartridge at phase P2-4. In phase P2-4, the Y developing cartridge is also in a driven state, but since the toner seal has been peeled off, the torque required for driving is smaller than during the unsealing operation, and the toner seal unsealing operation of the M developing cartridge is performed. have little impact on Thereafter, the rotating shaft 411 is further rotated forward, and the toner seal of the developing cartridge C is unsealed at phase P2-5. Although the Y and M developing cartridges are also driven, since the toner seals of the respective developing cartridges are peeled off, the toner seal of the C developing cartridge can be unsealed without any problem. This control is suitable for a configuration in which the rotary shaft 411 is rotated in only one direction.
It should be noted that the specific example of the sequential toner seal pulling operation described here is merely an example, and various operation orders can be adopted according to the device configuration.

<Simultaneous toner seal opening operation for all colors determination unit (A) (details of S506)>
Here, the all-color simultaneous toner seal unsealing operation determination means will be described. In this embodiment, in order to shorten the downtime as much as possible, the toner seal unsealing operation is performed at the same peripheral speed as during the normal printing operation.

The image forming apparatus 200 is provided with motor drive detection means (not shown) for detecting a signal emitted from the drive motor and detecting whether the motor is rotating. For example, a counter that counts FG (Frequency Generator) signals corresponds to this motor drive detection means. The FG signal counter may be provided as dedicated hardware, or the control unit 300 may be made to perform the function. When dedicated hardware is provided, the count number is read by the control unit 300 . When the simultaneous toner seal opening operation for all colors is attempted, the controller 300 can determine whether or not the motor is rotating based on whether or not a signal is detected from the motor drive detection means. It is possible to determine whether or not the toner seal opening operation can be performed.

First, when the controller 300 determines that at least one new developing cartridge 204 other than black (K) is attached to the image forming apparatus 200, the developing rollers 217 of all the developing cartridges 204 and drum cartridges 213 and the photosensitive drum 1 are separated. Also, all the clutches 403 are in the OFF state. Therefore, in order to drive the developer cartridge 204, the control unit 300 drives the drive motors M1 and M2 and turns on all the clutches 403. FIG. At this time, the developing roller 217 and the photosensitive drum 1 in the developing cartridge 204 and the drum cartridge 213 come into contact with each other. Of the developing cartridges 204 attached to the image forming apparatus 200, all the clutches 403 are turned on, and all the clutches 403 are turned on regardless of whether the developing cartridges 204 of yellow, magenta, cyan, or black are new. The photosensitive drum 1 and the developing roller 217 are brought into contact with each other at the same time.

Subsequently, the developing cartridge 204 is driven by the drive motor M2 of the image forming apparatus 200, and the motor drive detection means determines whether the motor is operating or rotating (operating) under a predetermined condition. to detect. That is, it is detected whether or not the driving motor is generating a predetermined rotational driving force without being overwhelmed by the torque. When the control unit 300 detects that the drive motor M2 is rotating (operating) or rotating (operating) under a predetermined condition, it determines that the simultaneous toner seal opening operation for all colors is possible. On the other hand, if the control unit 300 does not detect that the drive motor M2 is rotating (operating) or rotating (operating) under a predetermined condition, the simultaneous toner seal opening operation for all colors cannot be performed. I judge. Here, rotating (operating) under a predetermined condition means, for example, rotating at a rotation speed equal to or more than half of the assumed rotation speed.

In this embodiment, the case where the FG signal is used to detect that the drive motor M2 is rotating (operating) or rotating (operating) under a predetermined condition has been described, but the present invention is not limited to this. isn't it. For example, a method of reading a motor drive current value, a method using a mechanism for determining whether a slit provided in a flange provided on a photoreceptor has passed a predetermined position, and a method of determining whether the current value of the charging roller 2 or the developing roller 217 is determined. You may judge by the method of detecting whether it is flowing or not.

<Black toner seal opening operation>
Next, the black toner seal opening operation will be described. The drum cartridge 213K and the developing cartridge 204K for black (K) have independent drive sources from the drum cartridge 213 and the developing cartridge 204 for colors other than black, respectively. Therefore, when it is determined that only the black (K) developing cartridge 204K is new, the black toner seal opening operation is performed for only the black (K) developing cartridge 204K.

When the controller 300 determines that the developing cartridges 204 other than black (K) are not new, the developing rollers 217 and the photosensitive drums 1 of all the developing cartridges 204 and the drum cartridges 213 are separated from each other. Therefore, in order to drive only the black (K) developing cartridge 204K, the black (K) clutch is turned ON. Subsequently, in order to open the toner seal 275, the photosensitive drum 1 and the developing roller 217 are rotated by the driving motor with respect to the black (K) drum cartridge 213K and the developing cartridge 204K. The developing roller 217 starts to be driven when the toner supply roller 220 driven by the main body transmits the driving force through gears. At this time, the peripheral speeds (movement speeds of the peripheral surfaces) of the photosensitive drum 1 and the developing roller 217 are 190 mm/sec and 250 mm/sec, respectively (first peripheral speed), similarly to normal printing.

Further, the driving force is also transmitted from the toner supply roller 220 to the stirring shaft 223b through the gear, and the stirring shaft 223b rotates to separate the toner seal 275 from the opening 218c, thereby communicating the toner storage chamber 218a and the developing chamber 218b. do.

<Simultaneous toner seal opening operation for all colors (B)>
Next, the simultaneous opening operation of all color toner seals will be described. When the controller 300 determines that the simultaneous toner seal opening operation for all colors can be executed, all the clutches 403 are in the ON state. Therefore, in order to unseal the toner seal 275, the controller 300 drives the driving motor M2 to rotate the stirring shaft 223. As shown in FIG. The stirring shaft 223 starts to be driven when the toner supply roller 220 driven by the main body transmits the driving force through a gear. At this time, the peripheral speeds (movement speeds of the peripheral surfaces) of the photosensitive drum 1 and the developing roller 217 are 190 mm/sec and 250 mm/sec, respectively (first peripheral speed), similarly to normal printing.

When the toner supply roller 220 receives the driving force, the driving force is transmitted to the agitating shaft 223b, and the agitating shaft 223b rotates, thereby separating the toner seal 275 from the opening 218c and communicating the toner storage chamber 218a and the developing chamber 218b. do.

<Sequential toner seal opening operation (C)>
In the sequential toner seal opening operation, the toner seal 275 is opened at least by one less than the total number (N) of the developing cartridges 204 that can be attached to the image forming apparatus main body 200 ((N-1) or less). perform the opening operation. All the clutches are in the ON state when it is determined that the simultaneous toner seal opening operation for all colors cannot be executed. Therefore, the controller 300 drives the development contact/separation motor M4 to selectively turn on one or more clutches.

For example, only the yellow (Y) clutch Y403 is turned on, and the drive motor M2 rotates the stirring member 223 at the same peripheral speed as during normal printing. As a result, the toner seal 275 of the developing cartridge 204Y for yellow (Y) is opened, and the toner storage chamber 218a and the developing chamber 218b are communicated with each other. After that, the yellow (Y) clutch Y403 is turned off.

This operation is sequentially performed for the magenta (M), cyan (C) and black (K) developing cartridges (204M, 204C and 204K) to complete the toner seal opening operation. An example of details is as shown in the timing chart of FIG.

Here, in order to verify the downtime reduction effect of this embodiment, the following verification experiment was conducted.

<Experiment 1>
When a new developing cartridge is attached to the image forming apparatus 200 under low-temperature and low-humidity conditions (temperature of 15° C., humidity of 10%), whether or not the simultaneous toner seal opening operation for all colors can be executed depends on the toner seal opening operation. I checked the time. If the simultaneous toner seal opening operation for all colors can be executed, it is marked with "O", and if it cannot be executed, it is marked with "X".

In this experiment, two types of developer cartridges, ie, a developing cartridge A with no unevenness of the toner in the toner storage chamber and a developing cartridge B with the unevenness of the toner in the toner storage chamber, were prepared. In the experiment, the types of developing cartridges to be attached to the image forming units (SY, SM, SC, SK) are indicated.
As a comparative example, it is assumed that the toner seal opening operation is sequentially performed without determining whether or not the simultaneous toner seal opening operation for all colors can be performed.
Table 1 shows the configuration for which the experiment was performed, and Table 2 shows the experimental results of each configuration.

In the present embodiment, it took a long time of 27 seconds in Examples 1-3 and 1-4, but such cases are rare. Actually, in most cases, the simultaneous toner seal opening operation for all colors can be performed, and the effect of shortening the toner seal opening time of 7 seconds can be obtained. On the other hand, in the comparative example, the toner seal opening operation was 23 seconds in all cases.

As described above, by determining whether or not the simultaneous all-color toner seal opening operation can be executed, in many cases, the simultaneous all-color toner seal opening operation can be executed. As a result, it is possible to facilitate response to requests for downsizing/sharing of drive sources (motors). In addition, a new developing cartridge 204 can be attached to the image forming apparatus 200 to reduce downtime on many occasions.

In this embodiment, the toner seal opening operation is performed for all the developing cartridges 204 attached to the image forming apparatus 200, but it may be performed only for the cartridges 204 determined to be new. Further, in this embodiment, the toner seal opening operation for a single developing cartridge 204 is repeatedly performed, but the number ((N−1)) less than the total number (N) attached to the image forming apparatus 200 is performed. ), the toner seal opening operation may be performed separately.

(Example 2)
In the first embodiment, whether or not the simultaneous all-color toner seal opening operation can be executed is determined based on the peripheral speed during normal printing operation, and the all-color simultaneous toner seal opening operation or the sequential toner seal opening operation is executed. However, the maximum torque that can be output by a driving motor (not shown) mounted on the image forming apparatus 200 cannot be output at the peripheral speed during normal printing operation. Therefore, even when the drive motor is originally capable of executing the simultaneous toner seal opening operation for all colors, the toner seal opening operation may be performed sequentially.

In the sequential toner seal winding operation, the drum cartridge 213 and the developing cartridge 204 are separated from each other in the process cartridge which is not performing the toner seal winding operation, so that only the drum cartridge 213 is driven. Normally, when the developing cartridge 204 and the drum cartridge 213 are in contact with each other, toner is sent from the developing roller 217 to the cleaning blade 6 via the photosensitive drum 1 . The fed toner acts as a lubricant at the contact portion between the photoreceptor drum 1 and the cleaning blade 6 , reduces the torque between the photoreceptor drum 1 and the cleaning blade 6 , and suppresses the vibration of the cleaning blade 6 . On the other hand, when the drum cartridge 213 is driven while the photosensitive drum 1 and the developing roller 217 are separated from each other, the toner is not sent to the contact portion between the photosensitive drum 1 and the cleaning blade 6, and the torque increases. Vibration of the cleaning blade 6 accompanying this torque increase may cause cleaning blade noise.

In order to solve this problem, in the second embodiment, when it is determined that the simultaneous toner seal opening operation for all colors cannot be executed due to the peripheral speed during the normal printing operation, the peripheral speed of the developing roller 217 is reduced and all the colors are printed again. An example of determining whether or not the simultaneous toner seal opening operation is executable will be shown. It should be noted that the configuration of the image forming apparatus, the configuration of the drum cartridge, the developing cartridge, etc. are the same as those of the first embodiment unless otherwise specified, and the description thereof will be omitted.

<Flowchart 2>
The toner seal opening operation when the developer cartridge 204 is detected to be new in this embodiment will be described with reference to the flowchart of FIG. Note that this flowchart is executed by the control unit 300 .

When the developing cartridge 204 is attached to the image forming apparatus 200 (S601), data communication is performed between the control section 300 and the D memory m2 via the memory communication section 306 (S602). Through data communication, the control unit 300 acquires the information of the new product flag (for example, if 0 is new, and if 1 is in use) from the D memory m2. (S603).

If it is determined that the installed developer cartridge 204 is not new, the controller 300 ends the process because the toner seal opening operation is not required (S611). If it is determined that the attached developing cartridges 204 are new, it is determined whether or not the attached developing cartridges 204 other than the black (K) developing cartridge 204 are new (S604). .

When it is determined that the developing cartridge 204 other than the black (K) developing cartridge 204 is not new, the control unit 3300 controls the driving motor M3 for rotating the stirring member 223 for black (K). A toner seal opening operation is executed (S605). After that, the process ends (S611). When it is determined that there is a new cartridge other than the black (K) developing cartridge 204, a simultaneous all-color, full-speed, simultaneous toner seal opening operation is determined by means for judging whether or not an all-color, full-speed, simultaneous toner seal opening operation can be executed. (S606). Describing the process of step S606 in more detail, the control unit 300 drives the drive motor M1 to operate the drive train described with reference to FIG. 7 operates, the ON/OFF state of each clutch 403 and the contact/separation state between the photosensitive drum 1 and the developing roller 217 transition as shown in the timing chart of FIG. If it is determined that the all-color, full-speed simultaneous toner seal opening operation is executable, the all-color, full-speed simultaneous toner seal opening operation is executed (S607), and then the process ends (S611). Further, when it is determined that the simultaneous all-color, full-speed toner seal opening operation is not executable, whether or not the all-color, low-speed simultaneous toner seal opening operation can be performed is determined by means for judging whether or not the all-color, low-speed simultaneous toner seal opening operation can be performed. (S608). The operation of the drive train described with reference to FIG. 7 in step S608 is the same as in the case of S606 described above. If it is determined that the simultaneous low-speed toner seal opening operation for all colors can be performed, the simultaneous low-speed toner seal opening operation for all colors is performed (S610), and then the process ends (S611). If it is determined that the simultaneous toner seal opening operation for all colors at all speeds is impossible, the sequential toner seal opening operation described in the first embodiment is executed (S609), and then the process ends (S611).

<Simultaneous Toner Seal Unsealing Operation (B1) for All Colors and All Speeds, and Acceptance Judging Means>
The simultaneous all-color, full-speed toner seal opening operation is the same as the all-color, simultaneous toner seal opening operation described in the first embodiment. Further, determination of whether or not the simultaneous toner seal opening operation for all colors at all speeds is possible (whether or not the motor is generating the first rotational driving force for rotating at the first peripheral speed) is the same as that described in the first embodiment. It is the same. Therefore, description here is omitted.

<Black toner seal opening operation>
Since the black toner seal opening operation is the same as that described in the first embodiment, the explanation is omitted.

<Low Speed Simultaneous Toner Seal Unsealing Means for All Colors (C1)>
Here, the low speed simultaneous toner seal unsealing means for all colors will be described. Whether or not simultaneous toner seal opening operation for all colors at low speed is possible is determined by whether or not a signal is issued by the motor drive detection means, as in the simultaneous toner seal opening operation for all colors at all speeds in the first embodiment. That is, whether or not the drive motor is generating the second rotational driving force for rotating the developing roller 217 at the second peripheral speed slower than the first peripheral speed in the simultaneous toner seal opening operation for all colors at all speeds. Judge by The only difference from the first embodiment is that the peripheral speed of the developing roller 217 is slower than that during normal printing.

<Simultaneous low-speed toner seal opening operation for all colors (B2)>
At the time when the low-speed simultaneous toner seal opening operation for all colors is executed, the photosensitive drums 1 and the developing rollers 217 in all the drum cartridges 213 and developing cartridges 204 are in contact with each other. That is, all developing cartridges 213 are in a state in which driving force can be transmitted. Therefore, in order to unseal the toner seal 275, the photosensitive drum 1 and the developing roller 217 are rotated through the drive motor for all the drum cartridges 213 and developing cartridges 204. FIG. The developing roller 217 starts to be driven when the toner supply roller 220 driven by the main body transmits the driving force through gears. At this time, the circumferential speeds (movement speeds of the circumferential surface) of the photosensitive drum 1 and the developing roller 217 are 96 mm/sec and 124 mm/sec, respectively, corresponding to 1/2 of the normal speed (second circumferential speed).

When the developing roller 217 receives the driving force, the driving force is transmitted to the agitation shaft 223b, and the agitation shaft 223b rotates to separate the toner seal 275 from the opening 218c, thereby communicating the toner storage chamber 218a and the development chamber 218b.

In the present embodiment, the circumferential speeds of the photosensitive drum 1 and the developing roller 217 are both reduced to 1/4, but the speed reduction ratio may be arbitrarily selected according to the configuration of the drive motor. In this embodiment, the peripheral speeds of the photosensitive drum 1 and the developing roller 217 are reduced at the same ratio, that is, the peripheral speed ratio is constant, but they may be reduced so that the peripheral speed ratios are different.

<Sequential toner seal opening operation (C2)>
Since the sequential toner seal opening operation is the same as that described in the first embodiment, the explanation is omitted.

Here, in order to verify the effects of reducing downtime and cleaning blade squeal according to the present embodiment, the following verification experiment was conducted so as to be able to compare with the present embodiment 1 and comparative example 1.

<Experiment 2>
When a new developer cartridge is attached to the image forming apparatus under low temperature and low humidity conditions (temperature 15°C, humidity 10%), whether or not the simultaneous toner seal opening operation for all colors at full speed has been executed, and whether or not the toner seal opening operation for all colors has been executed at low speed It was confirmed whether or not the toner seal opening operation was performed. In addition, the time required for opening the toner seal and the presence or absence of cleaning blade noise were checked. When the simultaneous toner seal opening operation for all colors and at all speeds was executed, "O" was written, and when it was not executed, "X" was written. If the simultaneous low-speed toner seal opening operation for all colors was executed, it is marked with "O", and if it was not executed, it is marked with "x". Furthermore, when the cleaning blade squeal did not occur, it was indicated as "O", and when it occurred, it was indicated as "X".

In this experiment, as in Experiment 1, two types of developer cartridges were prepared, ie, the developer cartridge A in which the toner in the toner storage chamber was not evenly distributed, and the developer cartridge B in which the toner was uniformly distributed. Also, two types of drum cartridges, a drum cartridge X having a cleaning blade with an MD-1 hardness of 65° and a drum cartridge Y having a cleaning blade with an MD-1 hardness of 80°, were prepared.

Table 3 shows the configuration for which the experiment was performed, and Table 4 shows the experimental results for each configuration.

As a result of Experiment 2, in the case of this embodiment, the ratio of the toner seal opening operation of 7 seconds was 50%, which is the same result as in the first embodiment.

On the other hand, the frequency of cleaning blade noise was 12.5% in Example 1 and 12.5% in Comparative Example 1.
is 50%, this embodiment is 0%. From this result, it was found that cleaning blade squeal was suppressed as compared with Example 1 and Comparative Example.

As described above, in addition to judging whether or not the simultaneous all-color, full-speed toner seal opening operation is executable, by judging whether or not the all-color, low-speed simultaneous toner seal opening operation is executable, all-color simultaneous toner Increased chances of being able to perform seal opening actions. As a result, in many cases where a new developing cartridge is attached to the image forming apparatus, it is possible to reduce the downtime due to the operation of opening the seal and suppress the cleaning blade noise.

Reference Signs List 1 Photoreceptor drum 6 Cleaning blade 200 Image forming apparatus 204 Developing cartridge 213 Drum cartridge 217 Developing roller 223 Stirring member 275 Toner seal 276 Toner seal winding shaft 300...control unit, 304...motor drive unit

Claims (14)

An image forming apparatus having a plurality of image forming units for each color of developer that forms a developer image by developing an electrostatic latent image formed on an image carrier with the developer carried by the developer carrier. There is
a device body;
(i) a first unit detachable from the apparatus main body and rotatably supporting the image carrier; and (ii) detachable from the apparatus main body and capable of rotating the developer carrier. an accommodating portion for accommodating the developer , an agitating member for rotating and agitating the developer accommodated in the accommodating portion, and a sealing member for sealing the opening of the accommodating portion in an unused state, and the sealing member that is provided on the rotation shaft of the stirring member and is wound up by rotation of the rotation shaft so that the opening is opened. ,
a driving unit having a motor and configured to transmit a rotational driving force of the motor to the plurality of image forming units;
drive detection means for detecting an operating state of the motor;
with
In a winding operation for winding the seal member by rotating the rotating shaft when the unused second unit is attached to the apparatus main body,
(A) driving the motor so that the rotational driving force can be transmitted to all of the plurality of image forming units;
(B) When the drive detection means detects that the motor is operating or is operating under a predetermined condition, all of the plurality of second units simultaneously rotate the rotating shafts . ,
(C) When the drive detection means does not detect that the motor is operating or that the motor is operating under a predetermined condition, the number of the second units that simultaneously rotate the rotating shaft is 1. An image forming apparatus, wherein said rotating shaft is sequentially rotated in a plurality of said second units so as to be smaller than the total number of said plurality of said second units. The first unit is arranged so that the first unit and the second unit take either a contact state in which the image carrier and the developer carrier are in contact with each other or a separated state in which the image carrier and the developer carrier are separated from each other. and a contact/separation mechanism for switching the relative positions of the second unit,
2. The drive means is configured so as not to transmit power to at least the developer carrying member and the rotating shaft when the first unit and the second unit are in the separated state. The image forming apparatus according to . (C) when the drive detection means does not detect that the motor is operating or that the motor is operating under a predetermined condition, one of the plurality of second units 3. The image forming apparatus according to claim 2, wherein the rotating shaft is rotated one by one. (C) When the drive detection means does not detect that the motor is operating or that the motor is operating under a predetermined condition, the unused second unit among the plurality of second units 3. The image forming apparatus according to claim 2 , wherein the rotating shaft is rotated only in two units. The second unit has a developing chamber in which the developer carrier is arranged, a developer containing chamber forming the container, and an opening communicating between the developing chamber and the developer containing chamber. having a frame,
5. The image forming apparatus according to claim 1, wherein the sealing member seals the opening. Some of the plurality of image forming units are configured to receive rotational driving force from the single motor,
In the several image forming units, when the unused second unit is attached to the apparatus main body, the winding operations (A), (B), and (C) are performed in the winding operation. The image forming apparatus according to any one of claims 1 to 5 . The rotating shaft is configured to rotate when the rotational driving force is transmitted from the developer carrier,
In the winding operation,
When the driving means drives the motor so as to rotate the developer bearing member at a first peripheral speed in a state in which the rotational driving force can be transmitted to all of the plurality of image forming units,
(B1) When the drive detection means detects that the motor is operating or is operating under a predetermined condition, all of the plurality of second units simultaneously rotate the rotating shafts . ,
(C1) When the drive detecting means does not detect that the motor is operating or is operating under a predetermined condition, the driving means moves the developer carrier to the first position. 6. The image forming apparatus according to claim 1 , wherein the motor is driven to rotate at a second peripheral speed slower than the peripheral speed. When the motor is driven so as to rotate the developer bearing member at the second peripheral speed in a state where the rotational driving force can be transmitted to all of the plurality of image forming units,
(B2) When the drive detection means detects that the motor is operating or is operating under a predetermined condition, all of the plurality of second units rotate the rotating shafts simultaneously. ,
(C2) If the drive detection means does not detect that the motor is operating or that the motor is operating under a predetermined condition, the number of the second units rotating the rotating shaft at the same time is 8. The image forming apparatus according to claim 7 , wherein the rotating shaft is sequentially rotated in the plurality of the second units so that the total number of the plurality of the second units is smaller than the total number of the plurality of the second units. Some of the plurality of image forming units are configured to receive rotational driving force from the single motor,
performing the (B1), (C1), (B2), and (C2) in the winding operation when the unused second unit is attached to the apparatus main body in the several image forming units; The image forming apparatus according to claim 8 , characterized by: 9. The image forming apparatus according to claim 7 , wherein the first peripheral speed is the same as the peripheral speed for forming the developer image. 11. The method according to any one of claims 1 to 10 , wherein a rotational driving force for rotating the image carrier, the developer carrier, and the rotary shaft in one image forming unit is transmitted from the single motor. The image forming apparatus according to any one of items 1 to 3. The number of motors included in the driving means is less than the total number of the plurality of image forming units,
12. The apparatus according to any one of claims 1 to 11 , wherein some of the plurality of image forming units are configured such that rotational driving force is transmitted from a single motor. image forming device. a memory provided in the second unit and storing information of the second unit;
a new article detection means for detecting whether or not the second unit attached to the apparatus main body is unused based on the information stored in the memory;
13. The image forming apparatus according to any one of claims 1 to 12 , further comprising: 14. The image forming apparatus according to any one of claims 1 to 13 , wherein the first unit further includes a cleaning member that is in sliding contact with and cleans the surface of the image carrier. .

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