JP3052733B2 - Cartridge and image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image on a sheet material such as a printer or a facsimile, and more particularly, to a detachable cartridge structure and an apparatus having the cartridge mounted thereon. .

[0002]

2. Description of the Related Art As a typical example of a conventional image forming apparatus or cartridge, a structure as disclosed in Japanese Patent Publication No. 63-67185 and US Pat. No. 4,835,565 is generally known. On the other hand, US Pat.
A plurality of rotating bodies adjacent to each other are arranged in a developing unit which is arranged to be movable toward and away from the photoconductor and pressed against the photoconductor. The rotating body which is supported so as to be movable toward and away from the main body, and is movable toward and away from the housing, includes an Oldham coupling formed at an end of a gear shaft which is provided in the developing unit case and driven by an idle gear driven from the main body. The driving structure is driven by the coupling means, and is effective with respect to the rotational driving of the rotatable member that can move in and out of contact.However, when the idle gear provided in the developing unit case is driven from the main body side, it is arranged in the above structure. In the developing unit, the pressing force is changed by the action of the axial force generated by the pressure angle of the gear driven from the main body, and the contact state with the photoconductor may become unstable.

Further, in the main view of Japanese Patent Publication No. 63-67185, a photosensitive member rotated and driven from the apparatus main body drives the developing means, and a driving force is applied to a driving portion of the photosensitive member. The drive unit of the apparatus main body and the driven unit on the cartridge side are large and expensive due to the necessity of having high rigidity.

[0004]

As described above, in the prior art, the state of urging is changed by the action of the axial force generated by the pressure angle of the gear driven from the main body, and the state of contact with the photosensitive member is changed. In addition, the image forming apparatus becomes unstable, and the apparatus becomes large.

[0005] In the environment surrounding computers in recent years, the downsizing has been spurred by the rise of small notebook computers, and the market for personal use has expanded. As described above, the demand for the miniaturization of external terminals such as printers and facsimile machines and the appearance of inexpensive products corresponding to the miniaturization of computers has increased.

SUMMARY OF THE INVENTION Accordingly, the present invention is to solve the above-mentioned problem. It is an object of the present invention to provide a cartridge driven by a main body of an image forming apparatus, wherein a driven portion of a photosensitive member and a developing means are provided. The driven part is divided into two parts, so that the driving force on the cartridge side or the driving part on the main body side is simplified while avoiding the concentration of the driving force. By constructing a stable driving relationship with a small amount of jitter, a small and inexpensive image forming apparatus has emerged, which particularly meets the demand in the personal use market.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a cartridge which is detachably mountable to an image forming apparatus main body and has a photoreceptor having rotation driven means rotatably driven from the image forming apparatus; visualized by developing the toner to the latent image formed by exposure, a developing means having a second driven rotatable means is rotated and is supported movable relative to the photosensitive member, the developing means Is at least the developing roller
And a blade for regulating a toner conveyance amount of the developing roller
A rotating support for movably moving the developing roller and the blade.
A support member for lifting, a first driven rotatable means is rotated from the image forming apparatus, a housing for supporting said photosensitive member and said developing means and said first driven rotatable means, said supporting
Urging the holding member toward the photosensitive member and the developing roller.
An urging means for rotating the blade in the space of the toner storage unit, and a rotational driving force of the first rotationally driven means interposed between the second rotationally driven means and the first rotationally driven means. And a universal coupling means for transmitting to the second rotation driven means.

According to the present invention, there is provided a photoreceptor having a rotationally driven means rotatably driven from an image forming apparatus, and a latent image formed by exposing the photoreceptor to a latent image formed by developing the toner to visualize the latent image. a developing unit having a second driven rotatable means is rotated and is supported movable relative to, said developing hands
The step includes at least a developing roller and toner of the developing roller.
A blade for regulating the transport amount, the developing roller and the blade.
A supporting member rotatably supporting the blade, the first rotating drive unit rotatably driven from the image forming apparatus , and supporting the photosensitive member, the developing unit, and the first driven rotational unit; A housing for urging the support member and the photosensitive member;
The developing roller and the blade toward the toner reservoir
Urging means for rotating and moving in the space of the second, the second rotationally driven means and the first rotationally driven means interposed between the second rotationally driven means and the rotationally driven force of the first rotationally driven means. An image forming apparatus, comprising: a universal coupling unit for transmitting the rotation of the photosensitive member and the second rotation driven unit to each other.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to FIGS.

FIGS. 1 to 10 show a suitable embodiment of the (cartridge and) image forming apparatus of the present invention, FIGS. 11, 12 and 13 show other embodiments, and FIG. FIG. 2 is a cross-sectional view of a main part on the left side showing the entire configuration of the image forming apparatus;
FIG. 2 is a sectional view of a main part of the front showing a cross section of the front main part.

FIG. 3 is a sectional view of a main part of the left side showing a cross section of the main part of the left side of the cartridge of the present invention. 4 and 5 are cross-sectional views of main parts of the right side of the image forming apparatus of the present invention. FIG. 4 is a cross-sectional view of main parts of a first right side, and FIG. 5 is a cross-sectional view of main parts of a second right side. Are cross-sectional views at different positions.

FIG. 6 is a developed cross-sectional view showing a part of a developed cross-section of the rotation drive transmitting portion of the image forming apparatus of the present invention.

FIG. 7 is a cross-sectional view of a main part of the right side of the cartridge of the image forming apparatus according to the present invention, showing the relation of the cartridge to be rotated.

FIG. 8 is a cross-sectional view of a main part of the upper surface of the cartridge of the image forming apparatus according to the present invention.

FIG. 9 is a cross-sectional view of a main part of the upper surface of the cartridge showing the rotational driving relationship of the cartridge of the image forming apparatus of the present invention.

FIGS. 10 to 13 are views for explaining the rotational drive relationship of the cartridge of the present invention. FIG. 10 is an explanatory view of a first rotary drive system, FIG. 11 is an explanatory view of a second rotary drive system, and FIG. FIG. 13 is an explanatory diagram of a three-rotation drive system, and FIG. 13 is an explanatory diagram of a fourth rotation drive system.

First, the image forming section of this embodiment will be described with reference to FIG. 1 and other figures.

The main part of the image forming means of this embodiment is shown in FIG.
The photosensitive drum 1, the charging roller 2, the cleaner unit 90, the developing unit 10,
It is constituted by the toner conveying sections 30 and 30a.

Referring to FIG. 1 and FIG. 3, the order of the image forming process will be described. The charging roller 2 in the present embodiment is formed of a semiconductive elastic material such as rubber, for example. DC (-) 2k while following the drum 1
When a bias of about v or less is applied, the photosensitive drum 1 can be charged to a charging potential of (−) 600 V to (−) 700 V.

The charging roller 2 is pressed and supported toward the photosensitive drum 1 by a pressing mechanism constituted by a spring 3 and the like, and is pressed against the photosensitive drum 1 with a total pressure of approximately 1 kg.

Next, the photosensitive drum 1 is image-exposed to form a latent image by a light beam emitted from an exposure unit 40 to be described later and incident from an optical path 49, and the potential of the image exposure unit is set to (-). ) 10 V to (−) 150 V.

Next, in the developing section 10, a supply roller 13 which is formed of a semiconductive elastic material such as foamed rubber and rotates in the direction of the arrow in FIG. The surface of the toner is coated with toner in a storage unit 11 that rotates, and rubs against a developing roller 12 that is formed of a semiconductive elastic material such as a rubber material that rotates in the direction of the arrow in the drawing, and rubs the toner. Is frictionally charged to the negative polarity, and the surface of the developing roller 12 is coated with toner.

The toner coated on the surface of the developing roller 12 is formed of, for example, an elastic body such as a stainless steel plate, and is in contact with the outer periphery of the developing roller 12 at a total pressure of about 1 kg over almost the entire area in the axial direction. By rubbing the applied toner with a regulating blade 14 for regulating the toner to a coating layer having a predetermined thickness, approximately 10
The toner layer is regulated by a toner layer having a thickness of about μm and is triboelectrically charged to a more uniform (−) polarity.

The DC (-) 200 is applied to the developing roller 12.
A bias of about V to (−) 400 V is applied,
The thinned toner layer is conveyed to the photosensitive drum 1 and reversely developed on a nip portion formed by pressing the developing roller 12 and the photosensitive drum 1 against each other and in the vicinity of the nip portion.

By the way, the toner in the storage unit 11 is as shown in FIG.
As shown in detail in FIG.
Cartridge lower case 18, regulating blade 14, pressing member 16 for regulating blade 14, developing roller 12
The space surrounded by the supply roller 13 is stored in a narrow predetermined space formed of, for example, a foamed rubber material and partitioned by an elastic seal 15.

Next, the toner image reversely developed on the image exposure portion of the photosensitive drum 1 is transferred by a transfer portion 80 described in detail later, and the remaining toner is a thin plate material such as a mylar sheet material. The rake sheet 91 slides through the formed rake sheet 91 and is scraped off by the cleaning blade 92 pressed against the photosensitive drum 1, and is stored in a predetermined space 93 formed by the rake sheet 91 and the cleaning blade 92.

The cleaned photosensitive drum 1 can be transferred to the next image forming process again. If the potential remaining on the photosensitive drum 1 is removed after cleaning by light irradiation or the like, the surface potential of the photosensitive drum 1 can be reduced. Can be brought closer to the initial state.

Here, handling of toner will be described. A conventional image forming apparatus is mounted as a cartridge in which a predetermined amount of toner corresponding to the operating life of the main components such as a photoreceptor is enclosed in an integrated casing, which not only increases the size of the entire apparatus but also replaces it. Although the workability of maintenance is enhanced, the image forming apparatus is expensive, but in this embodiment, the configuration is completely different from the conventional concept.

First, the amount of toner in the storage unit 11 is reduced to a minimum necessary amount that does not hinder the above-described image forming process, and the space of the storage unit 11 is reduced. The toner that decreases with the development is dropped and replenished from the toner transport unit 30a that transports the toner, which will be described in detail later, in the space of the storage unit 11.

On the other hand, the toner scraped off by the cleaning blade 92 is stored in a predetermined space 93 formed by the rake sheet 91 and the cleaning blade 92.
Move to zero.

As will be described in detail later, the toner conveying sections 30 and 30a include toners including endless coil springs 31 and 31a (separated for the sake of explanation in the drawing, but endless and integral). A mechanism for transporting the toner by the transporting means is provided, and the toner transporting units 30 and 30a, which are disposed at substantially horizontal left and right positions with the photosensitive drum 1 being substantially at the center in the figure, are formed by a structure described in detail later. The toners of the toner transport unit 30 and the toner transport unit 30a are connected and circulated and transported.

Next, the toner circulation function will be described. With respect to the amount of toner (development toner amount) in the storage unit 11 consumed by the above-described development, the amount of untransferred toner scraped off by the cleaning blade 92 and transferred to the toner conveyance unit 30 (reproduction toner amount) Is 10% to 30% in the present embodiment. Even if the toner is circulated and conveyed, the toner is consumed by the repetition of the development, Will decrease.

Therefore, in this embodiment, in order to compensate for the reduced toner, as will be described in detail later, a toner replenishing means which falls by its own weight is arranged in the transport path for circulating the toner. Is supplied and circulated and transported together with the above-mentioned regenerated toner.
1 is configured to be replenished.

Next, the stable structure of the nip portion formed by pressing the developing roller 12 and the photosensitive drum 1 rotatably supported by the cartridge lower case 18 will be described with reference to FIGS. 3, 8 and 9. explain.

The supply roller 13 made of a semiconductive elastic material such as foamed rubber and the developing roller 12 made of a semiconductive elastic material such as rubber are used as metal cores. The support portions 12a and 13a are provided at both ends of the elastic body, and the support portions 12a and 13a are rotatably supported by the support member 5 as shown in FIG. Have been. 9 shows a state in which the supply roller 13 and the developing roller 12 support the right side, but the opposite side has the same support structure, and is rotatably supported by the support member 5A in FIG.

The supply roller 13 and the developing roller 12
3 is supported at a fixed pitch that is smaller than the pitch at which the outer circumferences of the supply roller 13 and the developing roller 12 are in contact with each other, and the outer circumferences of both rollers are evenly contacted over the entire area in the longitudinal direction. It is configured in the positional relationship shown in detail.

Then, the supply roller 13 and the developing roller 12
Are rotationally driven in the direction of the arrow shown in the drawing to rub. When the distance between the support pitches is extremely narrow, the rotational driving torque increases, and the deterioration of the toner rubbed between the two roller nips is deteriorated. In this embodiment, in consideration of the absorption of the variation of the components related to the support, the support is performed at a fixed pitch 0.25 mm narrower than the pitch at which the outer circumferences of the supply roller 13 and the development roller 12 are in contact with each other.

The supporting member 5 and the supporting member 5A, which rotatably support both ends of the supply roller 13 and the developing roller 12, respectively,
As shown in FIG. 3, the support member 5 is rotated by a support pin 5a inserted through a part of the cartridge lower case 18, and is firmly connected via a connecting member 6 by fixing means such as a screw. 3 shows a state in which only one side is supported, but the other side has the same supporting structure, and the supporting member 5 shown in FIG.
A is inserted through a part of the cartridge lower case 18 and is rotatably supported by a similar support pin 5Aa disposed at the same sectional position as the support pin 5a shown in FIG.

Then, the supply roller 13 and the developing roller 12
Are rotatably supported at both ends by a supporting member 5a and a supporting pin 5Aa together with the regulating blade 14 in a state of being connected by a connecting member 6 so that the above-described image forming process is not hindered. It can rotate integrally with the photosensitive drum 1 in the space of the toner storage unit 11 configured to limit the storage amount.

When the support pin 5a and the support pin 5Aa are arranged at the above positions, the cartridge lower case 18 and the support member 5 and the support member 5A can be easily rotated based on the integrated structure. The relationship is such that a gap is formed so as to be free in the rotation direction, and this gap is shielded by an elastic seal member (not shown) to prevent leakage of toner.

On the other hand, in order to form a stable nip by pressing the developing roller 12 and the photosensitive drum 1 in the above state, the developing roller 12 is rotated around the support pin 5a and the support pin 5Aa as a supporting shaft, and the developing roller 12 is exposed to light. Springs 8 and 8A for urging in the direction of the drum 1 are provided between the lower cartridge case 18, the support member 5, and the support member 5A.

Incidentally, with respect to the support member 5 and the support structure of the support member 5A by the support pin 5a and the support pin 5Aa, in this embodiment, as a means for preventing a rotation problem even if a difference occurs between the left and right support positions. In one of the support portions, the insertion portion through which the cartridge lower case 18 and the support pin 5a of the support member 5 are inserted is rotatably formed by supporting the support pin 5a in a desired relationship, and the other support portion is provided with the cartridge lower portion. The insertion part through which the support pin 5Aa of the case 18 and the support member 5A is inserted is not shown in detail, but the support pin 5Aa
Is provided with a desired clearance so as to be able to move toward and away from the photosensitive drum 1 to prevent the occurrence of a rotation problem of the above configuration.

In this embodiment, the desired clearance is provided in the support portion of the support pin 5a. However, the desired clearance may be provided in the support pin 5Aa.
Even if it is provided on both sides of Aa, the occurrence of the rotation failure of the above configuration is prevented.

Here, the toner replenishing means and the toner conveying means for circulating and conveying the toner will be described with reference to FIGS. 2, 7 and 8.

As shown in FIG. 3, while the endless coil springs 31 and 31a for circulating and conveying the toner are sealed by the cartridge upper case 17 and the cartridge lower case 18, the toner tank 20 can be freely attached / detached (attach / detach mechanism). Is filled with a predetermined amount of toner, is mounted in a toner-enclosed state and replenishes toner, and when this toner is consumed, it is replaced with a new toner tank 20. It has a configuration.

The endless coil springs 31 and 31a for circulating and transporting the toner are separated from each other for convenience of explanation in the drawing, but are formed as an endless and integral one.

The main part of the toner tank 20 includes a cylindrical tank case 21 having a bottom at the bottom in the figure, a cover 22 fixed above and sealing the toner, and a tank case 21 and a cover 22. Plural blades 23 that stir rotatable toner sealed with toner
b, and an endless coil spring 31 for circulating and transporting the toner.
The attachment / detachment operation is possible (the attachment / detachment mechanism is omitted from the illustration in detail) with respect to the state in which the cartridge 31a is enclosed by the cartridge upper case 17 and the cartridge lower case 18.

On the other hand, in order to drive the endless coil springs 31 and 31a for circulating and conveying the toner in the direction of the arrow in FIG. 8, an endless coil enclosed so as to be circulated by a cartridge upper case 17 and a cartridge lower case 18. The drive means 25 of the coil springs 31 and 31a is arranged in a part of the arrangement path of the springs 31 and 31a.
When the toner tank 20 is mounted at a predetermined position, the wedge-shaped rotatable convex portion 25a and the concave portion 23c formed at one end of one agitator 23 are engaged and driven to rotate. You.

The driving means 25 of the endless coil springs 31 and 31a for circulating and conveying the toner can be driven by a rotating body which can be engaged with the coil springs 31 and 31a. The engagement relationship with the coil springs 31, 31a is stabilized by employing a helical gear having a twist angle approximating the lead angle of the stretched state of the 31, 31a.

The toner agitated by the rotation of the agitator 23 circulates and transports the toner through an opening 21a formed at the bottom of the tank case 21 and an opening 17a of the cartridge upper case 17 provided opposite the opening 21a. Endless coil springs 31, 31a
Is dropped by its own weight into the toner circulation / conveying path in which the toner tank 20 is disposed.
1a and opening 17a are opened and closed. (Not shown) The toner dropped by its own weight in the toner circulating conveyance path in which the coil springs 31 and 31a are disposed is circulated and conveyed in the direction of the arrow in FIG.
When the flow goes to a, the toner drops by its own weight from the upper portion of the supply roller 13 and is stored in the toner storage unit 11 described above with reference to FIG. 3, but as described above, the toner storage unit 11 is configured to be extremely narrow. The toner storage unit 11 may be full due to the relationship between the toner consumption and supply depending on the image form. In this state, the toner is circulated and conveyed by the coil springs 31 and 31a without falling by its own weight. The structure is such that the fall of the toner from the toner tank 20 by its own weight is also interrupted.

The above is the main part of the image forming means of this embodiment. The photosensitive drum 1, the charging roller 2, the cleaner 90, the developing unit 10, and the toner conveying units 30, 30a are arranged in the above-described relationship. A cartridge lower case 18 which mainly serves as a main part and a cartridge upper case 17 which also plays a role of a cover thereof can be detachably attached to the main body as a cartridge having a unit structure. To perform repair or replacement.

The relationship between the cartridge and the main body is determined by a positioning means (not shown) and fixed by a fixing means (not shown).

Next, the transfer section 80 for transferring the reversal-developed toner image to the image exposure section of the photosensitive drum 1 will be described with reference to FIG.

The main part of the transfer section 80 of this embodiment is pressed by the pressing mechanism 82 toward the photosensitive drum 1 with a total pressure of several hundred g from below, and the latent image of the image exposure section of the photosensitive drum 1 is reversely developed. DC1K of opposite polarity to the toner image
A means for applying a bias of about V is provided. The rotatable transfer roller 81 is formed of a conductive or semiconductive elastic material such as rubber, for example. The sheet material transport base 71 supports the transfer roller 81 together with the constituent members. The sheet material transport base 71 is engaged with a positioning portion formed on a main chassis 100 serving as a reference of the internal structure of the apparatus. (Not shown), and is fixed to the main chassis 100 by fixing means such as screws.

The toner image conveyed to the nip formed by the pressing action of the photosensitive drum 1 and the transfer roller 81 is separated from the sheet fed from the sheet conveyer 70 described later in detail. It is transferred and merged.

Next, the fixing section 60 for feeding the sheet material on which the toner image on the photosensitive drum 1 is transferred and fixing the sheet material will be described.

The main part of the fixing unit 60 of this embodiment is a fixing roller which is disposed on the downstream side in the sheet material conveying direction and has a built-in heating element such as a halogen heater as a heating means in a hollow part of the aluminum pipe material and is rotatable. 63 and a pressing mechanism such as a spring 66 pressed against the fixing roller 63 with a total pressure of several kg as pressing means for pressing the toner image transferred onto the sheet material. A pressure roller 67 formed at least on the surface of a semiconductive elastic body and rotatable at the same peripheral speed as the fixing roller 63; and a discharge roller pair for discharging the conveyed sheet material to the outside of the apparatus. 61, and a fixing base 64 that supports the fixing members and supports the fixing unit 60 in a unit configuration. The fixing base 64 serves as a reference for the internal configuration of the apparatus. Is fixed to the main chassis 100 by chromatography by engagement of the positioning portion (not shown) for positioning portion formed in the sheet 100 is positioned at a predetermined position, for example, screws or the like fixing means.

The toner image transferred from the transfer section 80 to the sheet material and conveyed to the nip formed by the pressing action of the fixing roller 63 and the pressure roller 67 is transferred to the sheet at a predetermined temperature at the nip. Be established.

Next, the paper feeding section 70 for feeding a sheet material such as paper toward the transfer section 80 will be described.

A sheet tray 72 is provided at the lower end of the sheet tray 72 which accommodates a large number of sheet materials P such as paper and is formed of a high frictional material such as rubber. Part 7
A well-known pressing mechanism 74 that selectively presses the paper feed roller 73 that can rotate freely is provided.

The sheet feeding section 70 on the apparatus main body side is arranged to face the sheet feeding roller 73 with the sheet material P interposed therebetween, and only the uppermost sheet material among the many sheet materials P is fed to the sheet feeding roller 73. A sheet material feed control mechanism 75 for separating the sheet material so as to be fed by the rotation of the sheet 73 and for preventing the second and subsequent sheet materials from being fed; A sheet material detecting unit 77 including a photo sensor and the like, which is disposed in a sheet material conveying path for feeding a sheet material such as paper toward 80, and detects the presence or absence of the sheet material; A sheet conveying base 71 for supporting the above-described transfer roller 81 together with a constituent mechanism is provided. Further, although not shown, a mechanism for releasing the pressing of the transfer roller 81 against the photosensitive drum 1 is also provided. Transfer unit 80 The sheet material transport base 71 is supported in a unit configuration. As described above, the sheet material transport base 71 engages with a positioning portion formed on a main chassis 100 serving as a reference of an internal configuration of the apparatus (see FIG. (Omitted), and is fixed to the main chassis 100 by fixing means such as screws.

When the sheet feeding roller 73 is driven to rotate in the above-described configuration, one sheet material follows the sheet material conveying path and is fed to the transfer unit 80 described above.

Here, the sheet material feeding control will be described. The sheet feeding roller 73 is rotated and driven by a desired command to feed one sheet material into the sheet material conveying path, and in response to a detection signal of the sheet material detecting means 77, the sheet feeding roller 73
The sheet is stopped in a state where the sheet material is sandwiched, and a standby state (standby state) for the above-described transfer is performed.

The stop timing of the sheet feeding roller 73 may be stopped by a detection signal of the sheet material detecting means 77, but after a predetermined time elapses from the detection signal by a delay means such as a timer, the sheet is stopped and waits. May be.

That is, the toner image reversely developed on the image exposure portion of the photosensitive drum 1 in the nip portion formed by pressing the developing roller 12 and the photosensitive drum 1 under pressure is transferred to the photosensitive drum 1 by the rotation of the photosensitive drum 1. The time required for the roller 81 to reach the transfer section 80 having a nip formed by pressing and contacting;
It is only necessary that the time required for feeding the sheet material from the standby state and for the sheet material to reach the transfer unit 80 be controlled to a desired relationship,
In the present embodiment, the latter is adopted.

In this embodiment, a sheet material detecting means 77 including a photo sensor for detecting the presence or absence of a sheet material is disposed in the sheet material transporting path of the sheet feeding section 70, and the other is provided by the fixing section 60. Fixing roller 63 and pressure roller 6
7, a second sheet material detecting means 65 similar to the sheet material conveying direction downstream from the nip portion formed by the pressing action of the sheet material 7, and detects the sheet material conveying state. The detection signal from the sheet material detection means 65 is processed in a predetermined relationship to monitor the jam state in the apparatus.

As described above, in the image forming apparatus of this embodiment,
A configuration in which a sheet material conveyance path through which a sheet material P is discharged from a fixing unit 60 including a pair of paper discharge rollers 61 from a paper supply unit 70 via a transfer unit 80 is disposed at a lower center of the cartridge and substantially in the center of the entire apparatus. It is.

Next, the exposure device 40 for exposing the photosensitive drum 1 to a latent image will be described. The main part of the exposure device 40 includes a motor 41 rotating at 10,000 rpm, a control circuit board (not shown) for controlling the rotation of the motor 41, and a motor 41.
A deflection scanning means 43 which is mounted on the output shaft of the scanner and rotates and deflects and scans a light beam emitted from a light emitting element such as a semiconductor laser (not shown), and an optical path 49 for irradiating the light beam toward the photosensitive drum 1. A reflection mirror 44 to be formed,
An exposure unit case 42 is formed by housing the above-mentioned main constituent members to form a unit. The exposure unit case 42 engages a positioning portion with a positioning portion formed on a main chassis 100 which is a reference of an internal configuration of the apparatus. (Not shown), and is fixed to the main chassis 100 by fixing means such as screws.

The deflection scanning means 43 is disclosed in Japanese Patent Application No. 5-121995 filed by the present applicant.
As described in detail in Japanese Patent Application Laid-Open No. 6-75162, it is possible to perform small and inexpensive optical scanning. In this embodiment, the optical path length from the deflection scanning means 43 to the photosensitive drum 1 is substantially set. Although set to 160 mm, a short optical path length of about 140 mm can be handled.

Next, the control section 50 for controlling the above-mentioned respective mechanical sections will be described with reference to FIGS. 1, 2 and 8. The main part of the control unit 50 includes a first control circuit board 51 which is arranged at the lowermost end of the device and at least a power supply circuit unit and an operation control circuit unit of each mechanism are arranged. The second control circuit board 52, which is arranged substantially perpendicular to the left end of the device and joined by a joining means such as a connector 53, for example, and connected to a connector means for receiving an external signal, is compactly and centrally arranged. I have.

The second control circuit board is provided with a controller which mainly controls image formation. The memory extension circuit 54 including, for example, a RAM, and an interface extension having a connection interface function with an external device are provided. Circuits and the like are configured to be detachable from the left end side of the device.

By the way, the first control circuit board 51 is provided between the main chassis 100 made of metal sheet and the lower shield plate 55 made of metal sheet which is disposed at the lowermost end of the apparatus to increase the rigidity of the apparatus and to perform a shielding function. Are located,
Electromagnetic noise intrusion from outside or electromagnetic noise outflow to outside is prevented.

The main chassis 100 has an upwardly squeezed portion 10 corresponding to a component mounted on the first control circuit board 51 and having a large mounting height, such as a power transformer.
0a is formed to improve the planar accuracy and rigidity of the main chassis 100, maintain the fixing unit 60, the sheet feeding unit 70, the transfer unit 80, and the like in a stable relationship, and form the first control circuit board. This effectively produces 51 mounting spaces and contributes to the downsizing of the entire device.

Further, connection from the first control circuit board 51 to each mechanism is required, and the wiring connector 10 provided at the end of the lead wire of the drive motor 103 to simplify this connection.
3b and the like are intensively connected, or the lead terminals 57 having elasticity are brought into pressure contact with each other to conduct electricity, thereby making electrical connection to various points.

On the other hand, the second control circuit board 52 is opposed to the main chassis 100 made of metal sheet metal, and
Protected by a shield case surrounding the periphery, intrusion of electromagnetic noise from the outside or outflow of electromagnetic noise to the outside is prevented similarly to the first control circuit board 51.

From now on, the drive transmission relationship of each of the above-mentioned structural parts will be described with reference to FIGS. 2, 4, 5, and 6, 7, 7, 8, 9, 10, 11, and 12. explain.

The main part of the drive transmission unit of this embodiment is the second control circuit board 5 with the first control circuit board 51 substantially at the center.
2 and are centrally arranged on the right side surface of the main chassis 100. The first wheel train 101 and the second wheel train 1
02 are provided opposite to each other, and a drive motor 103 having a drive gear 103a on an output shaft and several kinds of drive gear trains to be described later are rotatably supported on the two wheel train receivers to form a unit structure. Main chassis 100 as a reference for configuration
The positioning of the portion to be positioned with the positioning portion (not shown) formed in the
4 and the like.

In the present embodiment, the first wheel train 101 and the second wheel train 102 are formed in a sheet metal structure. As will be described in detail later, there is provided a means for inexpensively making use of their characteristics. Is the feature.

In this embodiment, the first control circuit board 5
1 is disposed immediately below the above-described sheet material transport path so that its plane area is substantially the same as the sheet material transport path, and the second control circuit board 52 and the main part of the drive transmission unit deviate from this sheet material transport path area. This arrangement is arranged on one side and the other side orthogonal to the sheet material conveyance direction, and contributes to downsizing of the apparatus, particularly downsizing in the height direction, which seeks to reduce the space and space to the limit.

Further, with respect to the arrangement of the toner tank 20 described above, similarly to the second control circuit board 52 and the main part of the drive transmission section, as shown in FIG. In addition to being arranged on one side and protruding from the outer case of the apparatus so that it can be mounted, not only contributes to downsizing of the apparatus in pursuit of reduction of the space and space, but also the outer case when the toner tank 20 is mounted. It is not necessary to release the operation, and the wearability is extremely good.

Referring to FIGS. 4 and 5, the entire driving system of this embodiment will be described. 4 and 5 show a preferred embodiment of a drive system used in the image forming apparatus of the present invention. Each of the drawings is a cross-sectional view at a different position. Both FIGS. 4 and 5 show the rotational center position of each gear. Is marked with + in the figure.
(Similarly in FIG. 7) First, referring to FIG. 5, for the driving system of the present embodiment, individual driving is performed after the common A # gear driven by the driving gear 103a provided on the output shaft of the driving motor 103. A description will be given for each system.

<First Driving System> The first driving system for rotating the photosensitive drum 1 is A # gear → J # gear → K #.
The gears are driven in the order of gear → L # gear, and the L # gear is a gear fixed to one end of the photosensitive drum 1 by a fixing means such as an adhesive, and is formed integrally with the photosensitive drum 1 by the attachment / detachment of the cartridge described above. , Connected to or disconnected from the first drive system.

The mounting and dismounting of the cartridge in this embodiment is performed by moving the cartridge in the vertical direction in the figure.

<Second Driving System> The second driving system for rotatingly driving the developing roller 12, which is a main component of the developing unit 10, includes A # gear → B # gear → C # gear → D # gear → E.
The # gear is driven in the order of the # gear, and the E # gear is rotatably supported by the cartridge lower case 18 at substantially the same axial center position as that of the developing roller 12 as described later. The driving force is transmitted to an F # gear fixed to a protruding end of a support portion 12a extending to one end of the developing roller 12 by, for example, fixing means such as press-fitting. 2 Connect or disconnect from the drive system.

<Third Drive System> The third drive system, which rotates the supply roller 13, which is a main component of the developing unit 10, is driven in the order of F # gear → G gear → H # gear. The # gear is a gear fixed to a protruding end of the support portion 13 a extending to one end of the supply roller 13 by a fixing means such as press-fitting.

<Fourth Driving System> Driving means 25 for driving the endless coil springs 31 and 31a for circulating and conveying the toner and the agitator 2 of the toner tank 20
The fourth drive system for rotating the third gear 3 is shown in FIGS. 4 and 7, and is driven in the order of the E # gear → M gear → N # gear.
The N # gear is a helical gear fixed to one end of the driving means 25 by, for example, fixing means such as press fitting.
The M # gear for driving this is a helical gear rotatably supported by the cartridge lower case 18 described above.

<Fifth Driving System> A fifth driving system for rotating the above-described paper feed roller 73 is shown in FIG.
The gears are driven in the order of B # gear → C # gear → P # gear → Q # gear → R # gear. The R # gear is a gear mounted on a clutch disposed at one end of the above-described paper feed roller 73. It is connected to the fifth drive system.

<Sixth Drive System> The sixth drive system for rotating the above-mentioned fixing roller 63 is A # gear → S # gear → T
The gears are driven in the order of # gear → U # gear, and the U # gear is a gear provided at one end of the fixing roller 63 described above.

<Seventh Drive System> The above-described discharge roller pair 61
Is driven in the order of the U # gear → V # gear → W # gear, and the W # gear is a gear provided at one end of the above-described paper discharge roller pair 61.

Next, the main parts of the drive system will be described in detail.

<First drive system> A # gear → J # gear → K
The first drive system for rotatingly driving the photosensitive drum 1 driven in the order of # gear → L # gear has a structure shown in detail in FIG. 6, and FIG. 6 is an exploded sectional view of this first drive system.

The drive gear 103a provided on the output shaft of the drive motor 103 mounted on the first train wheel receiver 101 faces the first train wheel receiver 101 and the second train wheel receiver 102, and its outer peripheral portion is mirror-finished. A rotatably supported by projection portions 101a and 102a formed in a state.
The gear # is driven, and the L # gear is driven by driving the K # gear via a J # gear rotatably supported by a projection portion 101b formed on the first wheel train 101 with the outer periphery mirror-finished. Leads to.

The J # gear is connected to the projection unit 101.
The detachment from the projection part 101b is prevented by the bush 105 attached to the tip end of the projection b.

For the K # gear support structure, A #
Similarly to the gears, the first wheel train 101 and the second wheel train 10
2 are rotatably supported by projection portions 101c and 102c formed in a mirror-finished outer peripheral portion so as to face each of the two, and have a very simple and inexpensive configuration that does not require a support shaft or a bearing member. .

On the other hand, the wheel train first receiver 1 provided oppositely
01 and the projection unit 10 of the second train wheel receiver 102
1a and 102a, projection units 101c and 102
c, it is necessary to secure a relative positional relationship between the projection units 101b in order to make each gear stably rotatable. In the present embodiment, in order to achieve the above object, it is necessary to secure a gear train. A plurality of projection portions 101d are provided from one receiver 101, and a plurality of projection portions 102d are provided facing each other from the second train wheel train 102. An engagement recess 101e is formed at a protruding end of the projection portion 101d.
Is provided at the protruding end of the projection portion 102d.
01e to engage with each other to form an engaging projection 102e for positioning.
The unit 1 and the wheel train second receiver 102 are connected to each other by a screw 106 while maintaining a predetermined positional relationship and a relative interval to form a unit.

Although the illustration of the engaging concave portion 101e or the engaging convex portion 102e is omitted, contrary to the above configuration, the engaging concave portion is in the projection portion 102d, the engaging convex portion is in the projection portion 101d, or The above-mentioned contents may be combined in the plurality of projection units 101d and 102d, and the projection units 101a and 101a of the first train wheel 101 and the second train wheel 102 may be combined.
02a, the projection portions 101c and 102c, and the projection portion 101b can be easily determined to have a predetermined relative positional relationship by pressing the wheel train first receiver 101 and the wheel train second receiver 102 of the sheet metal structure using a progressive die or the like. Configurable.

Although the above-described structure has been described by taking the first drive system as an example, this embodiment is also applied to the other drive systems described above, although illustration is omitted.

The driving motor 103 of this embodiment is
An inexpensive PM type stepping motor is used, and smooth continuous rotation driving is enabled by controlling input pulses and current.

<Second Drive System> and <Third Drive System> A second drive system for rotating the developing roller 12 which is a main component of the developing unit 10 and a third drive system for rotating the supply roller 13. The main part of FIG. 10, FIG. 11, FIG.
2 and FIG. 13 are shown in detail. FIG. 10 shows a suitable embodiment, and FIGS. 11, 12 and 13 show other embodiments, and FIG. 11, FIG. 12 and FIG. 1
The parts different from 0 are the parts shown in the cross section AA and the cross section BB in the figure, and the other parts are exactly the same, so they will be described using the same reference numerals.

The D # gears of the second drive system, which are driven in the order of A # gear → B # gear → C # gear → D # gear → E # gear, are the respective D # gears described with reference to the first drive system. Like the gears, the first and second gear trains 101 and 102 are rotatably supported by projection portions 101f and 102f, each of which has an outer peripheral portion formed in a mirror-like state, facing each of the first and second gear trains 101 and 102. The E # gear which is connected to or disconnected from the D # gear by attachment / detachment is firmly connected to the D # gear via the connecting member 6 described above with reference to FIGS.
a and a fixing means such as press-fitting to a protruding end of a support member 5 rotatably supported by a support pin 5Aa and a support portion 12a extending to one end of a developing roller 12 rotatably supported by the support member 5A. F fixed by
Opposite to the # gear, it is rotatably supported by a support shaft 19 provided by a fixing means such as press-fitting in a cartridge lower case 18 substantially at the same axis position as the developing roller 12.

Similarly, an H # gear fixed to a protruding end of a support portion 13a extending to one end of the supply roller 13 rotatably supported by the support member 5 and the support member 5A, for example, by press-fitting or the like. Is configured to transmit drive from the F # gear to the H # gear via a G # gear rotatably supported by a shaft portion 5b protruding from the support member 5,
The developing roller 12 and the supply roller 13 are rotatably supported by the support member 5 and the support member 5A, and are supported by the support pin 5a and the support pin 5Aa together with the regulating blade 14.
As shown in FIGS. 3, 8, and 9, the developing roller 12 is urged toward the photosensitive drum 1 by the springs 8 and 8A. 1, and a stable nip portion is formed. The position of the developing roller 12 is influenced by, for example, variations in the outer diameter of the photosensitive drum 1 and the developing roller 12 and the rotation of the rotating shaft.

Therefore, in this embodiment, the gears from the E # gear to the F
In order to stably transmit the rotational driving force to the # gear, in the embodiment of FIG. 10, a convex portion E, which is parallel to a line symmetry orthogonal to the rotation axis, is provided on the BB cross section of one E # gear. #A, and a convex portion F # a parallel to the line axis orthogonal to the rotational axis is formed in the AA cross section of the other F # gear, and both convex portions E # a and convex portions F # a are formed. #A orthogonally slidable concave portion 26 that engages with #a
a so-called universal coupling 110 for transmitting a rotational driving force from the E # gear to the F # gear in the direction of the arrow in the figure with the piece member 26 having
In addition to absorbing the difference between the rotational axes of the gear and the F # gear, for example, in the case of meshing drive, a nip portion formed by pressing the developing roller 12 and the photosensitive drum 1 against each other due to the generation of axial force generated by the pressure angle of the gear. It will be unstable,
In this embodiment, the above phenomenon is reduced.

In this embodiment, as a consideration for facilitating the assembly of the universal coupling 110, a contour portion E # b is formed in the BB cross section of the E # gear, and the concave portion 26a is formed in the convex portion E # a. When the F # gear protruding toward the E # gear side from members such as the H # gear and the G # gear near the F # gear is slid in the radial direction, The engagement with the convex portion F # a is facilitated.

The universal coupling 110 constructed as shown in FIG. 10 has the above-mentioned scores, but the drive transmission efficiency and the axial force are reduced by the convex portion E # a of the E # gear and the piece member. 26 recess 26a and piece member 26
This is achieved by the reduction of the sliding friction loss between the concave portion 26b and the convex portion F # a of the F # gear and the effective driving force transmission direction.

Therefore, in another embodiment shown in FIG. 11, a concave portion having surfaces E # c parallel to each other symmetrically with respect to the axis of rotation is formed in the BB cross section of one E # gear, and the other F # gear is formed. # Surfaces F # parallel to each other symmetrically with respect to the rotation axis center point on the AA cross section of the gear
c, and a piece member 27 having projections 27a and 27b slidable in the orthogonal direction by being engaged with the recess having the surface E # c and the recess having the surface F # c. So-called universal coupling 110 for transmitting rotational driving force from the E # gear to the F # gear in the direction of the arrow in the figure.
And performs the same operation as described above with reference to FIG. 10. In particular, in the structure shown in FIG. 11, the rotation drive transmission from the surface E # c to the convex portion 27a and the rotational drive from the convex portion 27b to the surface F # c
With regard to the transmission of the rotational drive to the motor, the operating direction at the point of application of the rotational drive transmission coincides with the respective rotational directions, so that the transmission efficiency is good.

Further, in the structure shown in FIG.
The #gear is formed of a resin such as polyacetal which is rich in slidability, and the bridge member 27 is formed by die casting of, for example, zinc, aluminum, brass or the like to improve the sliding compatibility with plastic.

In the embodiment of FIG. 11, similarly to the embodiment of FIG. 10, as a consideration for facilitating the assembly of the universal coupling 110, a contour portion E # b is provided on the BB cross section of the E # gear. The projection 27a is formed in the recess having the surface E # c.
When the F # gear protruding toward the E # gear from members such as the H # gear and the G # gear near the F # gear is slid from the radial direction, The concave portion having the surface F # c of the F # gear facilitates engagement of the piece member 27 with the convex portion 27b. (In this engagement, the convex portion 27b of the piece member 27 can enter while rotating the E # gear from one outside of the continuous concave portion having the surface F # c and can be fixed at a predetermined position.) Next, another improved embodiment will be described with reference to FIG. In another embodiment shown in FIG. 12, a recess having surfaces E # d parallel to each other symmetrically with respect to the center of the rotation axis is formed in the BB cross-section of one E # gear, and the A- gear of the other F # gear is formed. A roller having a concave portion having surfaces F # d parallel to each other symmetrically with respect to the axis of rotation at the cross section A, and a roller rotatably supported by the concave portion having both surfaces E # d and the concave portion having surface F # d. A so-called universal coupling 110 that transmits a rotational driving force from the E # gear to the F # gear in the direction indicated by an arrow in FIG. 10 has the same effect as described above in FIG.
In the structure shown in (1), regarding the rotation drive transmission from the surface E # d to the roller 29 and the rotation drive transmission from the roller 29 to the surface F # d, the operation direction at the point of application of the rotation drive transmission coincides with each rotation direction. As a result, the transmission efficiency is good, and the sliding friction loss generated when the piece member 28 moves is configured to be extremely small due to the rolling friction.

In the structure shown in FIG. 12, the roller 29 is made of a resin such as polyacetal which is rich in slidability.
Numeral 7 is formed by die-casting of zinc, aluminum, brass or the like to improve sliding compatibility with plastic.

In the embodiment of FIG. 12, similarly to the embodiment of FIG. 10, as a consideration for facilitating the assembly of the universal coupling 110, the surface E # d formed on the BB cross section of the E # gear is used. The concave portion having a discontinuity is prevented from falling out of the piece member 28 engaged via the roller 29 by making the F #
When the F # gear protruding toward the E # gear from members such as the H # gear and the G # gear near the gear is slid in the radial direction, the concave portion having the F # gear surface F # d allows the piece member 28 to rotate. This facilitates engagement with the roller 29 supported by the roller. (In this engagement, the piece member 28 that rotatably supports the roller 29 can enter from the outside of one of the continuous concave portions having the surface F # d while rotating the E # gear and be fixed at a predetermined position. Next, another embodiment which is further improved will be described with reference to FIG. Another embodiment shown in FIG. 13 is a universal coupling 1 having a structure shown in FIG.
10 is a further improved structure, and only the improved universal coupling 110 will be described.

In another improved embodiment shown in FIG. 13, a concave portion having surfaces E # d parallel to each other symmetrically with respect to the center point of the rotation axis is formed in the BB cross section of one E # gear. F
A concave portion having surfaces F # d parallel to each other symmetrically with respect to the axis of rotation is formed in an AA cross section of the # gear, and an AA cross section of the F # gear is provided between the E # gear and the F # gear. A concave portion similar to the plane F # d parallel to the rotational axis center point symmetrically formed in the portion and a plane E # d parallel to the rotational axis center point in the BB cross section of the E # gear. Floating member 1 with similar recess
20 and the concave portion having the surface E # d of the E # gear and the concave portion similar to the surface F # d of the floating member 120, and the concave portion similar to the surface Ed of the floating member 120 and the surface F # of the F # gear In the concave portion having a d, two piece members slidably engaged with each other via a roller 29 rotatably supported and interposed in the orthogonal direction are interposed, and the gear member is rotated from the E # gear to the F # gear in the arrow direction in the figure. The so-called universal coupling 110 that transmits the driving force is configured to perform the same operation as described above with reference to FIG.
In the structure shown in FIG. 13, regarding the rotation drive transmission from the surface E # d to the roller 29 and the rotation drive transmission from the roller 29 to the surface F # d, the operation direction at the point of application of the rotation drive transmission is the respective rotation direction. And the transmission efficiency is good, and the sliding friction loss caused when the piece member 28 moves is configured to be extremely small due to the rolling friction, and the rotational axes of the E # gear and the F # gear are greatly different. However, the structure is such that the floating member 120 floats and rotates flexibly without being restrained by anything, and the nip portion formed by pressing the developing roller 12 and the photosensitive drum 1 is further stabilized.

The structure of the universal coupling 110 having the floating member 120 can be applied not only to the improvement of the structure shown in FIG. 12, but also to the improvement of the structure shown in FIGS. 10 and 11. .

On the other hand, in the present embodiment, as described in the above <First drive system> and <Second drive system>, the drive operation of the photosensitive drum 1 and the developing unit 10 is dispersed with respect to the drive of the cartridge. The driven section or the drive section on the main body side has a structure that does not need to be configured with high rigidity, and there is no load state concentrated on the driven section on the cartridge side or the drive section on the main body side. In this configuration, vibration and chatter are suppressed, and driving with less rotation jitter is possible.

Regarding the above-described image forming apparatus or cartridge of the present embodiment, the points to be noted here are summarized as follows.

<Regarding the Configuration and Driving Relationship of the Cartridge> The photosensitive drum 1, the charging roller 2, the cleaner unit 90, the developing unit 10, the toner conveying unit 30,
30a are arranged in the above-described relationship, and the cartridge lower case 18 mainly serving as a main part and the cartridge upper case 17 also serving as a cover thereof serve as a unit structure so as to be detachable from the main body. In the cartridge of the embodiment, the supporting member 5 and the supporting member 5A, which rotatably support both ends of the supply roller 13 and the developing roller 12, which are main parts of the developing unit 10, are fixed with a screw or the like via the connecting member 6, for example. As shown in FIG. 3, the support member 5 is rotatably supported by a support pin 5a inserted into a part of the cartridge lower case 18, as shown in FIG. Although a state where only one side is supported is shown, the opposite side has the same support structure, and the support member 5A shown in FIG. Similar support pins 5A which is arranged in the same cross-sectional position and support pins 5a shown in FIG. 3 by inserting a portion of the
a rotatably supported by the support pin 5a and the support pin 5a and the support pin 5Aa together with the above-described regulating blade 14 to support the image forming process as described above so as to minimize the necessary storage amount. Toner storage 1
1, a spring 8 for urging the developing roller 12 toward the photosensitive drum 1 as described above with reference to FIGS. 3, 8 and 9. And 8A, the developing roller 12 becomes the photosensitive drum 1
The position of the developing roller 12 is influenced by, for example, variations in the outer diameter of the photosensitive drum 1 and the developing roller 12 and the rotation of the rotary shaft.

The supply roller 13 and the developing roller 1
2 has an H # gear and an F # gear at one end thereof, and the H # gear is provided with an F # gear via a G # gear rotatably supported by a shaft 5b protruding from the support member 5. This is a configuration in which the drive is transmitted from.

The E # gear for transmitting the rotational driving force to the F # gear is provided by a fixing means such as press-fitting into the cartridge lower case 18 which is substantially coaxial with the developing roller 12 and faces the F # gear. The F # gear and the E # gear are rotatably supported by a support shaft 19 shown in FIGS.
The so-called universal coupling 110 described in detail with reference to FIGS. 1, 12 and 13 can be driven by absorbing the difference between the rotation axes of the E # gear and the F # gear.

As described above, the photosensitive drum 1 is provided with an L # gear as driven means, and the cartridge lower case 18
Is provided with an E # gear as driven means for the supply roller 13 and the developing roller 12, and a K # gear, a D # gear, etc. are provided on the main body side as a means for driving these, depending on whether the cartridge is attached or detached. Are configured to be engaged or disengaged correspondingly to each other, and are configured to be driven in a driving and driven relationship in the mounted state, and to drive the photosensitive drum 1 and the developing unit 10. The working positions are dispersed,
Since the concentration of the driving force is avoided, the driven part on the cartridge side or the driving part on the main body side does not have to be made large or configured with high rigidity.

According to the above configuration, the conventional USP
A plurality of rotating bodies adjacent to each other are arranged in a developing unit which is freely movable toward and away from the photoconductor and is pressed and urged against the photoconductor, as in 4835565.
One of the rotators is relatively movably supported, and the rotator is an end of a gear shaft provided in the developing unit case and driven by an idle gear driven from the main body. In the present embodiment, unlike the drive structure driven by a coupling means such as an Oldham's joint, the supply roller 13 and the developing roller 12 are driven by a cartridge lower case 18 rotatably supporting the photosensitive drum 1. As a means, an E # gear is provided.
The # gear is driven by a D # gear mounted on the main body, and the F # gear, which is rotatable around the support pin 5a and the support pin 5Aa, is not driven from the main body. The phenomenon that the developing roller 12 and the photosensitive drum 1 are in pressure contact with each other due to the generation of an axial force caused by the pressure angle at the time of meshing with each other and the nip portion formed is unstable is reduced.

Since there is no concentrated load on the driven part on the cartridge side or the driving part on the main body side,
Vibration and chatter are suppressed, driving with little rotational jitter is possible, and extremely stable image formation with little image pitch fluctuation and density fluctuation is performed. This is particularly effective for a high-resolution image forming apparatus.

Further, as described above, the developing unit 10 of this embodiment
The main part of the toner cartridge is supported by the lower cartridge case 18 and supported around the support pin 5a in the space of the toner storage part 11 which is configured to have a minimum necessary storage amount which does not hinder the image forming process. It has a structure which performs a corresponding movement by being urged to move and has a toner hopper for storing a desired amount of toner in a developing section as shown in the conventional example of JP-B-63-67185. Unlike the developing unit including and supporting the developing unit, the supporting state of the developing unit does not change according to the change in the toner amount, and the relationship between the photosensitive drum and the developing unit does not become unstable.

On the other hand, in the above-described configuration of the present embodiment, the main components of the developing unit 10 from the photosensitive drum 1 in the space of the toner storage unit 11 configured to have a minimum necessary storage amount without interfering with the image forming process. The above-described effect has been described on the basis of the configuration in which the unit is rotated and urged to perform a corresponding movement, and the toner is supplied from the toner conveying unit 30a to the toner storing unit 11, but this effect is stored. The toner transport section 3 is provided in
The present invention is not limited to the configuration in which the toner is replenished from 0a. Even in a configuration in which a desired amount of toner is stored in the toner hopper as in the conventional example, the developing unit in the toner hopper A similar effect can be obtained even in a configuration in which a corresponding movement is performed by being rotationally biased.

Here, focusing on the driving relationship between the photosensitive drum 1 and the main part of the developing unit 10, the developing unit 1 of this embodiment is considered.
The main part 0 is a structure that is supported by the cartridge lower case 18 and is rotated and urged around the support pins 5a and 5Aa to perform a corresponding movement. When the F # gear is driven via the universal coupling 110, each driven body is driven in the direction of the arrow shown in FIG. 3, and is driven in this direction by the universal coupling 110 described above with reference to FIGS. Then, at a position away from the support pins 5a and 5Aa, E #
F # from the gear via the universal coupling 110
The developing roller 1 is driven by the moment at which the gear is driven.
2. Developing section 10 of supply roller 13 and regulating blade 14
The main part of the nip portion is configured such that a moving force acts in a direction away from the photosensitive drum 1 to balance the pressing force of the springs 8 and 8A so that the developing roller 12 is pressed against the photosensitive drum 1 to form a nip portion. Even if the driving torque changes due to a change in humidity or deterioration in durability, the nip portion does not become unstable due to a biting phenomenon or chattering because the developing roller 12 has a moving behavior in a direction away from the drum 1.

On the other hand, at a position away from the support pins 5a and 5Aa, the universal coupling 1
The moving force acting on the main part of the developing unit 10 of the developing roller 12, the supply roller 13, and the regulating blade 14 in the direction away from the photosensitive drum 1 by the moment when the F # gear is driven via the F # is simply F # Compared to a structure that drives a gear, it is extremely small, has little fluctuation and is stable, and is excellent in the stability of the nip portion.

The above moving force is applied to the support pin 5 shown in FIG.
The distance between the photosensitive drum 1 and the developing roller 12, the supply roller 13, and the regulating blade 14 may not necessarily be reduced by increasing the distance between the photosensitive drum 1 and the developing roller 12. A support pin 5a is provided at a position where a moving force acts in a direction in which the main part of the developing unit 10 is separated.
3 and 5Aa, a stable nip portion can be formed. The arrangement of the support pins 5a and 5Aa is not shown, but may be located below the developing roller 12 in FIG. .

In the present embodiment, the developing roller 12 and the supply roller 13 are used for the main part of the developing section 10. However, the supply roller 13 is not an essential condition of the above structure, and uses a one-component magnetic toner. As in the conventional example represented by the configuration of the developing unit, the developing unit 10 has a structure in which the main part is constituted only by the developing roller 12, and the photosensitive drum 1 is limited to a cylindrical drum. But not
Although not shown, the above-described effect is exhibited even with an endless belt-shaped photosensitive member, for example.

The main part of the developing unit 10 of this embodiment is as follows.
The relationship between driving and driven has been described based on a structure in which the cartridge is supported by the cartridge lower case 18 and is rotated and biased about the support pin 5a as a support center to perform a corresponding movement. On the other hand, this is an example in which the main part of the developing unit 10 can be relatively moved and relatively simple and can be configured in a small size, and is driven by a so-called universal coupling 110 described in detail with reference to FIGS. With respect to the above, the above-described structure is not an essential condition, and the above-described effects can be applied to the case where the rotary driving is performed on a rotating body configured to be movable relative to the photosensitive drum 1.

Further, in this embodiment, the main parts of the image forming means of the photosensitive drum 1, the charging roller 2, the cleaner unit 90, the developing unit 10, and the toner conveying units 30, 30a are replaced by the cartridge lower case 18 and the cartridge upper case 17. The cartridge is configured to be detachable from the main body as a cartridge that is housed in a unit. However, toner that decreases with development is circulated and supplied from an exchangeable toner tank 20 that is detachably provided. In the present embodiment having such a configuration, there is no problem even if the configuration is not the cartridge configuration detachable to the main body as described above, but is a configuration integrated with the main body.

[0128]

As described above, the present invention provides a developing roller, a blade for regulating the amount of toner transported by the developing roller,
A support member that movably supports the developing roller and the blade; and an urging unit that urges the support member to rotationally move the developing roller and the blade toward the photoconductor in the space of the toner storage unit. With this configuration, only the developing roller and the blade move relative to the support member integrally, regardless of whether the amount of toner in the developing unit is large or small. The relative positional relationship between the roller and the blade can be kept constant, and extremely stable image formation with little image pitch fluctuation and density fluctuation is performed.This is an effective technology especially for high-resolution image forming apparatuses. The practical effects of the invention are extremely large.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part on a left side showing an embodiment of an image forming apparatus of the present invention.

FIG. 2 is a cross-sectional view of a main part of an image forming apparatus according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part of a left-side surface showing an embodiment of the cartridge of the present invention.

FIG. 4 shows a first embodiment of the image forming apparatus according to the present invention.
FIG.

FIG. 5 shows a second embodiment of the image forming apparatus according to the present invention.
FIG.

FIG. 6 is a developed sectional view showing an embodiment of the image forming apparatus of the present invention.

FIG. 7 is a cross-sectional view of a main part on the right side showing an embodiment of the cartridge of the image forming apparatus of the present invention.

FIG. 8 is a cross-sectional view of a main part of the upper part showing one embodiment of the cartridge and the image forming apparatus of the image forming apparatus of the present invention.

FIG. 9 is a sectional view of a main part of the upper surface of the cartridge showing an embodiment of the cartridge of the image forming apparatus of the present invention.

FIG. 10 is an explanatory diagram of a first rotation drive system showing an embodiment of the cartridge of the present invention.

FIG. 11 is an explanatory view of a second rotation drive system showing another embodiment of the cartridge of the present invention.

FIG. 12 is an explanatory view of a third rotation drive system showing another embodiment of the cartridge of the present invention.

FIG. 13 is an explanatory view of a fourth rotation drive system showing another embodiment of the cartridge of the present invention.

[Explanation of symbols]

 Reference Signs List 1 photosensitive drum 2 charging roller 5, 5A support member 5a, 5Aa support pin 8, 8A spring 10 developing unit 12 developing roller 13 supply roller 17 upper cartridge case 18 lower cartridge case 20 toner tank 30, 30a toner transport unit 31, 31a coil Spring 40 Exposure unit 50 Control unit 51 First control circuit board 52 Second control circuit board 60 Fixing unit 64 Fixing base 70 Feeding unit 71 Sheet material transport base 72 Feeding tray 73 Feeding roller 80 Transfer unit 81 Transfer roller 90 Cleaner Part 92 Cleaning blade 100 Main chassis 101 Wheel train first receiver 102 Wheel train second receiver 103 Drive motor 110 Universal coupling

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-1-166075 (JP, A) JP-A-4-181965 (JP, A) JP-A-5-53426 (JP, A) JP-A-5-53426 273848 (JP, A) JP-A-56-125756 (JP, A) JP-A-4-242768 (JP, A) JP-A-61-46551 (JP, U) (58) Fields investigated (Int. Cl. ^7, DB name) G03G 13/08 G03G 15/08 G03G 15/00 550 G03G 21/16 - 21/18

Claims (2)

(57) [Claims] An image forming apparatus includes: a cartridge detachably mountable to a main body of an image forming apparatus; a photosensitive body having a rotation driving unit rotatably driven from the image forming apparatus; and a latent image formed by exposing the photosensitive body to light. Developing means having a second driven driving means rotatably supported and movably supported relative to the photosensitive member, the developing means comprising at least a developing roller, Low
A blade for regulating the amount of toner transported by the developing roller;
And a support member for rotatably supporting the blade and the blade.
A, a first driven rotatable means is rotated from the image forming apparatus, a housing for supporting said photosensitive member and said developing means and said first driven rotatable means, and urging the support member The developing roller faces the photoconductor.
Biasing means for rotating the roller and the blade in the space of the toner storage unit; and rotation of the first rotationally driven means interposed between the second rotationally driven means and the first rotationally driven means. A universal coupling means for transmitting a driving force to the second rotation driven means,
A cartridge comprising: 2. A photoreceptor having a rotation driving means rotatably driven from an image forming apparatus; and a latent image formed by exposing the photoreceptor to a latent image formed by developing the toner to visualize the latent image. Developing means having second rotationally driven means rotatably supported and movably supported by the developing means, the developing means includes at least a developing roller, and a developing roller.
A blade for regulating the amount of toner transported by the developing roller;
And a support member for rotatably supporting the blade and the blade.
A, a first driven rotatable means is rotated from the image forming apparatus, a housing for supporting said photosensitive member and said developing means and said first driven rotatable means, and urging the support member The developing roller faces the photoconductor.
Roller and the blade in the toner storage space
Biasing means for causing said second universal coupling for transmitting rotational driving force of the first driven rotatable means interposed between the rotary drive means and the first driven rotatable means to the second driven rotatable means An image forming apparatus, comprising: a rotation unit configured to rotate the photosensitive member and the second rotation driven unit.