JP2000003093A - Developing sub-unit and image forming device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing sub-unit where toner is not leaked when it is a simple substance before it is integrated with a drum sub-unit. SOLUTION: The developing sub-unit 48 being a simple substance before it is combined with the drum sub-unit 66 is equipped with a developing casing 72 housing toner and a developing roller and other members and supporting parts 71a and 71b supporting the unit 66, and a sheet member 90 stuck at the time of shipping from a factory is disposed at a lower aperture part 89 where a part of the developing roller is exposed. The member 90 is constituted by cutting resin film whose thickness is 50 to 150 μm to long length, the aperture part 89 is sealed by a double-coated adhesive tape 91 and sponge 92 disposed on one surface thereof, and a knob part 93 extended to both sides is folded and encloses the bearing hole 81 of the supporting part 71a and the bearing groove 88 of the supporting part 71b from inside so as to inhibit the engagement with the unit 66, whereby the sealing in the case of the simple substance and the release of the sealing at the time of assembly are ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing sub-unit which does not leak toner when not in use, and an image forming apparatus provided with the developing sub-unit.

[0002]

2. Description of the Related Art Conventionally, in copiers and printers,
2. Description of the Related Art There is a developing device that transfers toner to an image carrier to convert a latent image on the image carrier into a toner image (development).

FIGS. 7 (a) and 7 (b) are perspective views showing a developing device in such a copying machine or printer, taken out of the apparatus, and showing a detachable developing device provided in a large-sized copying machine or printer. The device is shown. FIG. 1A shows a state in which the developing roller cover 2 is removed from the developing device 1, and FIG.
Indicates a state in which the developing roller cover 2 is attached to the developing device 1.

The developing device 1 includes a lower unit including a developer accommodating section, a developer stirring section, a doctor blade, a developing roller 3 having a part of the peripheral surface exposed to the outside, although the internal structure is not particularly shown. , Developer hopper, developer concentration detector,
An upper unit including a developer replenishing mechanism and the like are screwed together and integrated to form a developing device 1 as a whole.

The developing device 1 is of a type in which a developer brush of toner protruding in a spike shape is formed on the peripheral surface of the developing roller 3 to perform development. For this reason, the peripheral surface of the developing roller 3 and the rotating surface thereof are rotated. A relatively wide gap is formed between the housing 5 and the peripheral edge 5 of the case 4 which is freely supported. Therefore, when the developing device 1 is a single unit before being mounted on an unillustrated apparatus main body (copier or printer), if the developing device 1 is handled or transported in a state in which the toner is stored in advance, the internal toner may leak out. Maybe. As shown in FIG.
The reason why the developing roller cover 2 is attached is to prevent the above toner leakage.

[0006] When a new assembly or replacement with an old product is performed, the operator removes the developing roller cover 2 and mounts the handle 6 on the apparatus main body as shown in FIG. Even if an operator erroneously attempts to mount the developing roller cover 2 on the apparatus main body with the developing roller cover 2 attached as shown in FIG. 3B, the mounting is prohibited by the stoppers 7 protruding from both ends of the developing roller cover 2 and the apparatus main body is The occurrence of problems such as damage to the internal member on the side is prevented.

In such a large-sized machine or a developing device of the type in which a developer brush is formed on a developing roller, various methods for preventing toner leakage around the developing roller as described above have been proposed.

[0008] In response to the increasing demand for miniaturization of OA equipment in recent years, full-color electrophotographic copying machines and printers that can be installed on a personal computer rack have been put to practical use. In such a full-color toner developing system, a developing device is required for each of three or four color toners. Since the main body of the apparatus is small, the developing apparatus to be assembled therein is extremely small. At present, many of the developing units are disposable and replaceable units which do not replenish the toner.

FIGS. 8A to 8D are perspective views showing the structure of an image forming unit for such a small machine. In the image forming unit for a small machine, if the machine is a large machine, an image carrier (photosensitive drum) mounted alone on the apparatus body side is also assembled in the unit as one of the unit constituent members. It consists of two sub-units.

FIG. 1A shows a drum sub-unit 11, in which a photosensitive drum is rotatably held, and an initializing charger, a peripheral cleaner, a waste toner conveying device, etc. which are in contact with the peripheral surface thereof. Is incorporated.

FIG. 1B shows the drum sub-unit 11.
And the developing sub-unit 12 which is a pair. The developing sub-unit 12 includes a support portion 1 that supports the drum sub-unit 11.
2 and a developing casing 13 containing a developer (toner)
And a developing roller 14 having a part of the peripheral surface exposed from the opening of the developing casing 13.
Although not shown, a toner agitating member, a toner supply roller, a doctor blade, and the like are provided inside 3.

A bearing hole 15 is formed in one of the supporting portions 12 of the developing sub-unit 12, and a bearing groove 16 is formed in the other supporting portion 12 so as to be cut out from above.
A fixing lever 17 is disposed near the upper opening.
The fixed lever 17 has a downstream portion attached to the support portion 12 by a hinge.

As shown in FIG. 1C, the drum protective cover 18 covering and protecting the lower peripheral surface of the photosensitive drum of the drum sub-unit 11 is located on the downstream side as indicated by the arrow A in FIG. After the lower peripheral surface of the photosensitive drum is exposed by sliding upward (to the left in the figure), the photosensitive drum is loaded into the support portion of the developing sub-unit 12 as shown by the arrow B in the figure. That is, one of the support shafts 19a and 19b of the photosensitive drum projecting outward from the side surface of the drum subunit 11 is
The other support shaft 19b is fitted into the bearing groove 16 of the other support portion 12 while the other support shaft 19b is fitted into the bearing hole 15 of the support portion 12 of the development sub-unit 12.

Then, as shown in FIG. 2D, the fixing lever 17 is rotated clockwise in the figure to prevent the support shaft 19b from falling out of the bearing groove 16, and the drum sub-unit 1
1 is temporarily fixed to the developing sub-unit 12. by this,
A drum gear integrated with the photosensitive drum and a roller gear 21 integrated with the developing roller 14 are engaged with each other to form an image forming unit 22.
Is configured.

Thereafter, when the image forming unit 22 is mounted on the apparatus main body, the support shafts 19a and 19b of the photosensitive drum and the support shaft 23a of the developing roller 14 (shaded in FIG. (Not visible) and 23b are fitted and positioned respectively, and the drive gear of the apparatus main body meshes with the drum gear of the photosensitive drum from below.

The image forming unit 22
Since a thin toner layer is formed on the peripheral surface of the developing roller 14 to perform development on the photosensitive drum, a doctor blade contacts the upper peripheral surface of the developing roller 14 and scoops the lower peripheral surface. The sheet abuts, and a sealing member is provided on a side surface. Therefore, there is almost no gap between the developing roller 14 and the developing casing 13.

[0017]

Nevertheless, if extreme vibration is applied, for example, while the developing sub-unit 12 is being transported by itself, the portion between the developing roller 14 and the developing casing 13, particularly, the portion where the scooping sheet is in contact with the developing roller 14 and the developing casing 13. Sometimes leaked toner inside. As described above, once the toner leaks to the outside, the toner is fine particles and easily scatters, causing toner contamination around the toner. This causes a problem of discomfort of the user.

However, even if an attempt is made to apply a configuration such as the developing roller cover 2 for large equipment shown in FIG. 7 to such a small unit, as shown in FIG. Since a development sub-unit, etc., for forming a small image forming unit integrally is not assumed, all of the conventional cover members named rigid members are made of a rigid material, and the mechanism is complicated. There is a problem that not only the handling is troublesome but also the cost of the member is high. Further, when the disposable developing sub-unit 12 containing the used-up toner which does not replenish the toner as shown in FIG. 8 is sealed, the developing sub-unit 12 reaches the user's hand until the first use rise. Since it is only for the purpose of using it in between, expensive members cannot be used.

If the apparatus main body is a full-color printer or the like, three or four image forming units are mounted in a small main body, so that the size of the image forming units is further reduced. In addition, toner particles are becoming finer and finer because toner images of three or four colors are superimposed on paper and transferred and fixed. Therefore, the cover member having the configuration shown in FIG. 8 has a problem that the toner that is leaking to the outside cannot be completely sealed. In any case, it is necessary to devise another method.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances,
An object of the present invention is to provide a developing sub-unit which does not cause toner leakage when it is not used so as to form an image forming unit integrally with the drum sub-unit.

[0021]

According to a first aspect of the present invention, there is provided a developing sub-unit comprising: a supporting portion for detachably supporting an image carrying sub-unit having an image carrier; and a developing casing for accommodating a developer. A developing roller that exposes a part of the peripheral surface from the opening of the developing casing, carries and transports the developer, and develops a latent image formed on the image carrier,
A developing sub-unit configured to be removably attached to an image forming apparatus main body as an image forming unit integrated with the image carrying sub-unit by supporting the image carrying sub-unit on the support portion; The developing casing has an adhesive portion that is releasably adhered to the peripheral edge of the opening, and a peeling handle at the end, and is attached to the unused developing sub-unit, and is formed between the peripheral edge of the opening and the peripheral surface of the developing roller. A flexible sheet member is provided to prevent the developer from leaking from between.

The flexible sheet member may be, for example,
As described in the above description, the developing sub-unit is made of a resin film, and when adhered to the developing sub-unit, the developing sub-unit cannot support the image carrying sub-unit. As described above, the peeling handle portion is arranged on the support portion.

According to a fourth aspect of the present invention, there is provided an image forming sub-unit having an image carrier, a supporting portion for detachably supporting the image carrying sub-unit, and a developing casing for housing a developer. A developing sub-unit having a developing roller for exposing a part of the peripheral surface from the opening of the developing casing to carry and transport the developer and develop a latent image formed on the image carrier; An image forming apparatus in which an image forming unit integrated by a unit is detachably mounted, wherein the developing sub-unit is not in use.
In order to prevent the developer from leaking from between the peripheral edge of the opening and the peripheral surface of the developing roller, an adhesive portion that releasably adheres to the peripheral edge of the opening of the developing casing and a peeling portion formed at an end portion are provided. The handle for peeling off the flexible sheet member having the handle portion is formed such that the image carrying sub-unit and the developing sub-unit cannot be integrated unless the flexible sheet member is removed. , And arranged on the support portion.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external perspective view of an image forming apparatus according to an embodiment, and shows a tandem type color image forming apparatus as an example. The color image forming apparatus 30 shown in FIG. 1 is a small-sized color image forming apparatus that can be mounted on, for example, a desktop-type personal computer rack, and is opened and closed on the front surface (right side in the figure) of the main body 31. A paper feed tray 32 is provided, and a paper cassette 33 is detachably provided at a lower portion. A large number of sheets P are placed and stored in the sheet cassette 33.

The upper cover 34 forms a paper discharge tray 35 together with the rear upper surface of the main body base 31, on which the image-formed paper discharged from the upper paper discharge port 36 is stacked. An upper cover opening / closing switch 37 is provided on the upper surface of the main body base 31 in front of the upper cover 34, and further includes a liquid crystal display device,
An operation panel 39 including a power switch, a plurality of data input keys, and the like is provided.

FIG. 2 is a side sectional view showing the internal structure of the above color image forming apparatus. As shown in the figure, inside the color image forming apparatus 30, a paper transport belt (hereinafter, simply referred to as a belt) 41 is disposed in a substantially flat loop shape in the front and rear direction at substantially the center, and both ends thereof are driven by a drive roller 42. , And circulates counterclockwise as indicated by arrow C in the figure. Four photosensitive drums 44 (44a, 44b, 44c, 44d) are arranged in a multistage manner in the paper transport direction (from right to left in the drawing) in the upper circulation portion of the belt 41,
Each photoreceptor drum 44 is individually surrounded (hereinafter, referred to as
Representatively, only the peripheral devices of the photoreceptor drum 44d are denoted by reference numerals), the cleaner 45, the initialization charging roller 4
6, a write head 47, a developing device 48, and a transfer sheet 49 are arranged.

Developing device 48 corresponding to photosensitive drum 44a
To the developing device 48 corresponding to the photosensitive drum 44d, the developing devices 48 include M (magenta: red dye), C (cyan: greenish blue) and Y, which are three primary colors of subtractive color mixture.
(Yellow: yellow) and K (black: black) toner dedicated to printing characters and black portions of images, for example.

The four write heads 47 are provided on the support member 5.
1 and is supported by the upper lid 34. Transfer sheet 49
Are arranged as members belonging to the belt unit. As will be described in detail later, the photosensitive drum 4
4, the cleaner 45, and the initialization charging roller 46 constitute a drum sub-unit, and the developing device 48 comprises various members therein to constitute a developing sub-unit. These two sub-units are combined to form an image forming unit.

The belt 41 is constantly urged downward by a tension roller 52 pressed against the back surface on the downstream side of the lower circulating section to maintain an appropriate tension. The suction roller 53 is in pressure contact with the upstream end of the upper circulating portion of the belt 53 to form a paper carrying portion. Belt 53
A standby roll pair 54, a paper feed guide path 55 below the standby roll pair, and a feed roll pair 56 at the lower end thereof are disposed further upstream in the transport direction. A paper feed end of the paper cassette 33 is located below the feed roll pair 56, and a paper feed roller 57 is disposed above the paper feed end.

On the other hand, downstream of the belt 41 in the paper transport direction (left side in the figure), a pressure contact roller, a heat roller, a separation claw, a peripheral cleaning device, an oil application roller, a temperature measurement device, which are assembled in a heat insulating housing. A fixing device 58 including a fixing device or the like is provided.
A discharge roller pair 59 is disposed behind the fixing device 58, and a paper discharge path 61 is formed above the discharge roller pair 59.
The end of 1 is opened above the rear part of the paper discharge tray 35, and a paper discharge roller pair 62 is arranged there.

An electrical unit 63 having an appropriate circuit board mounted thereon is disposed between the belt 41 and the paper cassette 33.
A control device including a plurality of electronic components is mounted on the circuit board. The control device includes a controller unit and an engine unit (not shown). The controller section is C
It consists of a PU (Central Processing Unit), a ROM (Read Only Memory), an EEPROM (Rewritable Read Memory), a frame memory, an image data transfer circuit, etc., and analyzes print data input from a host computer or the like. Create print data and transfer it to the engine.

The engine unit includes a CPU, a ROM, and the like.
The input side receives data and command signals from the controller unit, the output of a temperature sensor (not shown), the output of a paper detection sensor, and the like.The output side is a motor driver that drives a motor (not shown). A predetermined bias current is supplied to a clutch driver for switching a drive system to be transmitted to each unit, a print driver for driving a write head 47 based on the print data, an initialization charging roller 46, a transfer sheet 49, a developing roller described later, and the like. A bias power supply driver and the like are connected. The engine unit drives and controls each unit based on data and command signals from the controller unit, outputs of various sensors, and the like.

FIG. 3A is an external perspective view showing only the above-mentioned image forming unit, and FIG. 3B is a side sectional view showing the internal structure thereof. In addition, FIG.
(a) is a side sectional view seen from the arrow E direction. Also,
2A and 2B, the same parts as those shown in FIG. 2 are denoted by the same reference numerals as in FIG.

As shown in FIGS. 3A and 3B, the image forming unit 65 includes a developing sub-unit 48 and a drum sub-unit 6.
6 are integrally assembled. One of the drum sub units 66 includes the photosensitive drum 44 shown in FIG.
The cleaning unit 45 includes a cleaner 45, an initialization charging roller 46, a drum cover 67 that can be moved back and forth (left and right in FIG. 3B), and a waste toner delivery pipe 68 inside the cleaning unit.

With the closing of the upper lid 34 (see FIG. 2),
The write head 47 descends along an arc-shaped trajectory as shown by an arrow F in FIG. 3 (b), and its tip (exposure portion) extends in the axial direction of the photosensitive drum 44 above the housing of the drum unit 66. And is positioned by fitting into a long slot 69 (see FIG. 3A) formed along.

The other developing unit 48 includes a supporting portion 71 (71a, 71b) for supporting the drum sub-unit 66,
Developing casing 72 containing developer (toner) 70
And a developing roller 73 having a part of the peripheral surface exposed from the opening of the developing casing 72. Further, inside the developing casing 72, a toner stirring member 74 is provided so as to be buried in the toner 70. A roller 75, a doctor blade 76, a scooping sheet 77 and the like are provided. A waste toner receiving pipe 78 is provided at an upper portion, and the waste toner receiving pipe 78 has a collection bag 79 for storing waste toner.
Is attached.

One supporting portion 7 of the developing sub-unit 48
A bearing hole 81 (see FIG. 3 (a)) is formed in 1a, and a bearing groove (described later) formed so as to be cut out from above is provided in the other support portion 71b. A fixed lever 82 is mounted near the upper opening so as to be rotatable up and down by approximately 90 degrees. A supporting shaft 83a of the developing roller 73 protrudes from a side surface of the developing sub-unit 48 on the supporting portion 71a side, and a supporting shaft 84a of the photosensitive drum 44 protrudes from the bearing hole 81. 3A, the other end 83b of the support shaft 83a of the developing roller 73 is provided.
Similarly, the other end 84b of the support shaft 84a of the photosensitive drum 44 projects from the bearing groove.

When the developing sub-unit 48 and the drum sub-unit 66 are assembled together and completed as an image forming unit 65 as shown in FIGS. 3A and 3B, a waste toner delivery pipe 68 and a waste toner receiving The pipes 78 are connected by a transport pipe 85 as shown by a broken line in FIG.

Next, the operation of the tandem-type color image forming apparatus 30 having the above configuration will be described with reference to FIGS. 2 and 3B again. First, the apparatus body 30 shown in FIG.
The printer is turned on, and when the paper quality, the number of sheets to be used, the print mode, and other designations are input as keys or signals from a connected host device, printing (printing) is started.

The paper feed roller 57 takes out one sheet of paper P placed and accommodated in the paper cassette 33, and feeds a pair of feed rollers 5.
6. The paper is fed to the standby roller pair 54 via the paper feed guide path 55. The rotation of the standby roller pair 54 is temporarily stopped, and the leading end of the paper P is brought into contact with the holding portion to stop the advance of the paper, and waits for the transport timing.

The driving roller 42 rotates counterclockwise, and the driven roller 43 is driven to rotate similarly in the counterclockwise direction. As a result, the upper circulating portion of the belt 41 abuts on the four photosensitive drums 44 and the entire belt 41 circulates counterclockwise.

At the same time, various devices arranged around the photosensitive drum 44 are sequentially driven in synchronization with the printing timing. The photoreceptor drum 44 rotates clockwise, the initialization charging roller 46 applies a uniform high negative charge to the peripheral surface of the photoreceptor drum 44, and the write head 47 applies a uniform negative charge to the peripheral surface of the photoreceptor drum 44. Exposure is performed according to an image signal to form a low potential portion. As a result, an electrostatic latent image composed of a high negative potential portion due to the initialization and a low negative potential portion due to exposure is formed.

The developing roller 73 transfers the toner 70 of the developing casing 72 to the low potential portion of the electrostatic latent image to form a toner image on the peripheral surface of the photosensitive drum 44 (reversal development). At the timing when the leading end of the toner image on the peripheral surface of the most upstream photosensitive drum 44a is rotated and conveyed to the portion facing the belt 41, the standby roller pair is set so that the printing start position of the paper P coincides with the facing portion. 54 starts rotating, and feeds the paper P to the paper loading section.

The driven roller 43 and the suction roller 53 hold and transport the fed sheet P together with the belt 41. The sheet P is attracted to the belt 41 and is conveyed to the first transfer section formed by the photosensitive drum 44a and the transfer sheet 49. The transfer sheet 49 applies a transfer current (or transfer voltage) output from a transfer bias power supply (not shown) to the belt 4.
1 to the sheet P. As a result, the M (magenta) toner image on the photosensitive drum 44a is transferred to the paper P.

Subsequently, a C (cyan) toner image is transferred at the second transfer portion from the upstream formed by the photosensitive drum 44b and the transfer sheet 49, and further formed by the photosensitive drum 44c and the transfer sheet 49. The Y (yellow) toner image is transferred at the third transfer portion from the upstream. Then, a K (black) toner image is sequentially transferred at the most downstream transfer portion formed by the photosensitive drum 44d and the transfer sheet 49, and four color toner images are overlaid.

The paper P on which the four color toner images have been transferred in this manner is separated from the belt 41 and carried into the fixing device 58. The fixing device 58 fixes the toner image on the paper P by heat and pressure. After the image is fixed, the sheet P is discharged by the discharge roller pair 59 onto the discharge tray 35 via the sheet discharge path 61 and the discharge roller pair 62 with the toner image facing down.

The color image forming apparatus 3 operating as described above
At 0, the image forming unit 65 is configured to be detachable (replaceable), and the drum sub-unit 66 and the developing sub-unit 48 are also individually replaceable according to the service life.

FIG. 4A shows the drum sub-unit 66 described above.
FIG. 3B is an external perspective view when the developing sub-unit 48 is present alone, and FIG.
(c) is a perspective view showing a configuration of the sealing member.

As shown in FIG. 3A, the drum sub-unit 66 includes support shafts 84a, 84 for the internal photosensitive drum 44.
b project outward from both sides, and the drum cover 67
Covers the lower surface of the photosensitive drum 44 to protect the lower peripheral surface thereof. On the side surface from which the support shaft 84b protrudes, a delivery portion (connection portion) of the waste toner delivery pipe 68 in which the delivery portion shutter 86 is fitted is protruded, and is projected on the cap-shaped head flat portion of the delivery portion shutter 86. A ridge 87 is formed.

As shown in FIG. 3B, the developing sub-unit 48 is provided below the side surface of the developing casing 72 at the other end 83b of the support shaft 83a of the internal developing roller 73 (see FIG. 3A).
Project outside. Fixed lever 82 of support portion 71b
Near the bearing hole 8 of the support portion 71a opposed thereto.
1, a bearing groove 88 is formed.
The developing roller 73 shown in FIG.
A sheet member 90 which is a main part of the present invention and is attached at the time of shipment from the factory is disposed in a lower opening 89 where a part of the sheet member 90 is exposed.

The sheet member 90 shown in FIG. 4C is made of polyethylene terephthalate and has a thickness of 50 to 150, for example.
A double-sided adhesive tape 91 is provided at a position corresponding to the lower opening 89 on one side (the other side in FIG. 4 (c)). The double-sided adhesive tape 91 is formed by applying an acrylic adhesive to both sides of a polyethylene film base material,
The side adhered to 0 has strong adhesiveness, and the side adhered to the lower opening 89 side has weak adhesiveness such that it can be re-adhered. It should be noted that the weakly bonded portion may be formed by another method.

An appropriate size sponge 92 is provided on one side of the sheet member 90 at a position corresponding to both ends of the peripheral portion of the lower opening 89 where the internal bearing and the gear of the developing roller 73 are located.
Are provided respectively. The sheet member 90 is further extended to both sides from the position where these sponges 92 are provided, and a handle portion 93 is formed. This sheet member 9
As shown in FIG. 6B, the adhesive is applied to the lower opening 89 of the developing casing 72 by using the adhesive member having a low adhesive strength, and a gap between the peripheral surface of the developing roller 73 and the peripheral edge of the lower opening 89 is formed. And the two sponges 92 are
3 is pressed against the internal bearing and gear to seal the periphery thereof. Thereby, the toner 70 inside is completely sealed,
No leakage to the outside.

Further, with the sticking of the sheet member 90, the handle portions 93 extended to both sides are naturally bent outward. Although the sheet member 90 is a thin film-shaped sheet, the sheet member 90 has appropriate rigidity, so that the handle portion 93 projects in the direction in which the support portions 71a and 71b protrude by the above-described bending without sagging. Thus, the inside of the bearing hole 81 of the support portion 71 a and the bearing groove 88 of the support portion 71 b are closed by the handle portion 93.

That is, when the developing sub-unit 48 is started to be used for the first time, the user or the like mistakenly mistakes the lower opening 8
When the drum sub-unit 66 is assembled without releasing the sealing of the drum 9, the handle 93 interferes with the support shafts 84 a and 84 b of the drum sub-unit 66 and the bearing holes 8.
1 and the bearing groove 88, so that it is possible to notice that the lower opening 89 has not been unsealed.

FIGS. 5A, 5B and 5C show the order in which the developing sub-unit 48 and the drum sub-unit 66 are assembled to assemble the image forming unit 65 shown in FIGS. 3A and 3B. FIG. 6 is a perspective view showing an assembled state. First, as shown in FIG. 7A, the developing casing 72 is held down by one hand 94 so that the developing sub-unit 48 does not move, and the handle 95 of the sheet member 90 is gripped by the other hand 95 to open the lower opening. The sealing is released by gradually peeling off from the portion 89, and as shown in FIG. 4B, a part of the peripheral surface of the developing roller 73 is exposed to the outside.

Next, as shown in FIG. 7C, the drum cover 67 of the drum sub-unit 66 is slid horizontally upward as indicated by the arrow G in FIG. Is exposed to the outside, then the drum sub-unit 66
Is indicated by the arrow H in FIG.
8 between the support portions 71a and 71b.

FIGS. 6 (a), 6 (b) and 6 (c) show the mounting of the drum sub-unit 66 on the developing sub-unit 48, the engagement mechanism between the fixing lever and the support, and the transfer of the waste toner. It is a sectional side view which shows a connection state. 5 (a), (b), and (c) show the configuration near the engagement portion of both sub-units, that is, FIGS. 5 (b) and 5 (c) as viewed from the direction of arrow J in the figure. Support part 71b
It is a side sectional view of a part.

First, one support shaft 8 of the photosensitive drum 44
4a is a supporting portion 71 of the developing sub-unit 48 shown in FIG.
6A, and then the other support shaft 84b is connected to the bearing groove 88 of the support portion 71b of the developing sub-unit 48 as shown by the arrow K in FIG. 6 (a).
And the drum sub-unit 66 is attached to the developing sub-unit 48.

After the mounting, as shown by the arrow L in FIG. 6 (b), the fixed lever 82 which has been opened is closed, and as shown in FIG. 6 (c), the support shaft 84b of the photosensitive drum 44 is supported. Temporarily fix so as not to deviate from the groove 88. In this state, the support shafts 84a and 84b of the photosensitive drum 44 protrude from the side surface of the image forming unit 65 (that is, the side surface of the support portion 71b) as shown in FIG.

The waste toner conveying pipe 85 of the developing sub-unit 48 and the waste toner delivery pipe 68 of the drum sub-unit 66 ( (See Fig. 3 (b))
Are opened and connected. This connection makes it possible to recirculate the removed toner (waste toner) generated on the drum sub-unit 66 side to the development sub-unit 48 side.

The transport pipe 85 of the developing sub-unit 48
The configuration and operation of the connecting portion between the feed pipe 68 of the drum sub-unit 66 and the sub-unit 66 will be further described. First, as shown in FIG. 6A, the outer end of the transport pipe 85 of the developing sub-unit 48 projects from the lower part of the developing casing 72 into the supporting portion 71b, and the conveying pipe 85 extends from the bearing groove 88 of the supporting portion 71b. Also, a toner receiving port 96 is provided at an upper portion below the downstream side (right side in the figure).

Above this, a fixed lever 82 set vertically at the reference position as shown in FIG. 5 (b) and a receiving shutter 97 shown in FIGS. 6 (a) to 6 (c) integrated therewith are provided. The cylindrical lid is formed in a shape obtained by cutting off the circumferential half surface, the cutout opening thereof is directed upward, and is rotatably supported by a support member 98 fixed to the support portion 71b. And the lower part of the remaining semi-peripheral surface is brought into contact with the receiving port 96.

In a state where the two sub-units are separated (FIG. 6 (a) shows a state immediately before the developing sub-unit 48 is connected to the drum sub-unit 66), the fixed lever 8
2 and the receiving section shutter 97 are connected to the supporting section 98 and the bearing groove 8.
The rotation is prohibited by the locking claw 99a of the rotation member 99 disposed between the eight.

FIG. 6A shows the state in this state (FIG. 4A).
(b) and FIGS. 5 (a) and 5 (b) are the same).
6 (see FIG. 6 (b)), a packing member having appropriate elasticity is arranged between the edge 6 and the contact surface of the receiving portion shutter 97, although it cannot be clearly seen in the drawing. Therefore, there is no gap between both the receiving section shutter 97 and the receiving port 96,
Thereby, the receiving port 96 is sealed.

The upstream side of the receiving section shutter 97 (FIG. 6)
An opening 97-1 is drilled in the peripheral surface facing left)
An elastic packing member is also attached to the inner surface around the edge. As shown in FIG. 6 (c), the fixing lever 82 is rotated by 90 degrees upstream to rotate the photosensitive drum shaft 8 of the photosensitive drum 44.
When 4b is temporarily fixed, the opening 97-1 rotates to a position corresponding to the receiving port 96 of the transport pipe 85.

As shown in FIG.
A groove 101 is formed by two protrusions whose cross sections face slightly obliquely upward in the drawing in the reference arrangement shown in (a) and (b) (the groove 101 is not formed as two protrusions but is formed on the bottom surface of the lid. It may be formed by drilling). The inclination of the groove 101 in the obliquely upward direction is formed to have the same inclination as the inclination of the bearing groove 88 formed so as to be notched obliquely from above. On the other hand, the drum sub-unit 66 on the side engaged therewith
As shown in FIG. 5C, a delivery shutter 86 of the waste toner delivery pipe 68 is arranged near the downstream side of the support shaft 84b of the photosensitive drum 44 at the side end of the photosensitive drum 44. A ridge 87 projecting from the outer surface of the bottom of the cylinder of the delivery shutter 86 is
It is guided and fitted into the groove 101 of the receiving section shutter 97,
The drum sub-unit 66 engages with the development sub-unit 48. At this time, in order to easily receive the ridge 87, the upper portion of the groove 101 is formed wide as shown in FIGS. 6 (a) to 6 (c).

In FIG. 6A, the delivery pipe 68
At the lower part of the peripheral surface of the end portion, a delivery port is bored though not visible. In the state shown in FIG. 6B, the outlet is fixed at a position facing the toner receiving port 96 of the transport pipe 85 via the receiving section shutter 97 and the transmitting section shutter 86 shown in FIG. 5C. I have.

Although not clearly shown in the drawing, an opening is formed in the upper peripheral surface of the sending part shutter 86 on the upstream side (right side in FIG. 5C). 6 (a) and 6 (b), the outlet of the delivery pipe 68 and the opening of the delivery shutter 86 are 9
The position is shifted by 0 degrees. Then, as shown in FIG. 6C, when the fixing lever 82 is rotated 90 degrees to the upstream side, the sending section shutter 86 shown in FIG. Rotate 90 degrees clockwise in c) (counterclockwise in FIG. 5C). By this rotation, the opening of the delivery section shutter 86 moves to a position corresponding to the delivery port of the delivery pipe 68. That is, the outlet of the delivery pipe 68 communicates with the receiving port 96 of the transport pipe 85 via the opening of the sending section shutter 86 and the opening 97-1 of the receiving section shutter 97.

When the drum sub-unit 66 is removed from the image forming unit 65 in the state shown in FIG. 6 (a) and is in a single state, the delivery section shutter 86 is turned by a rotation prohibiting member (not shown). The rotation is prohibited and the outlet of the delivery pipe 68 is kept sealed.

As described above, the image forming unit 65 shares a space for collecting the waste toner and a space for supplying the unused toner, and is small in size and inexpensive to dispose. 66 and the development sub-unit 48 are formed so that they can be exchanged individually, and when both units are present independently, the toner flowing portion is completely sealed to prevent toner leakage.

[0071]

As described in detail above, according to the present invention, when the developing sub-unit is a single unit, the opening is sealed with a flexible sealing member made of a cheap and light resin sheet. Stopping and blocking the engaging portion with the drum sub-unit by using the gripping portion of the flexible sealing member, preventing toner leakage of the disposable developing sub-unit and erroneously sealing when assembling the drum sub-unit. The image forming unit can be released without any problem, and the usability of the image forming unit is improved.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a tandem type color image forming apparatus according to an embodiment.

FIG. 2 is a side sectional view showing an internal configuration of the tandem type color image forming apparatus of FIG.

3 is an external perspective view showing only the image forming unit of FIG. 2 taken out, and FIG. 3 (b) is a side sectional view showing the internal configuration thereof.

4 (a) is an external perspective view when the drum sub-unit of FIG. 3 is provided alone, FIG. 4 (b) is an external perspective view when the developing sub-unit is also provided alone, and FIG. It is a perspective view showing composition of a stop member.

5 (a), 5 (b) and 5 (c) show a developing sub-unit 48 and a drum sub-unit 66 of FIG. 4 in order to assemble an image forming unit.
FIG. 6 is an assembled perspective view showing a procedure for assembling the hologram.

6 (a), (b) and (c) show the order of assembling the developing sub-unit and the drum sub-unit in FIG. 5, the engagement mechanism between the fixed lever and the support, and the connection state of the waste toner transfer part. FIG.

7A is a diagram illustrating a state in which a developing roller cover is removed from a conventional developing device, and FIG. 7B is a diagram illustrating a state in which a developing roller cover is attached to the developing device.

8 (a) to 8 (d) are perspective views showing the configuration of a conventional image forming unit for a small machine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Developing device 2 Developing roller cover 3 Developing roller 4 Housing 5 Peripheral edge 6 Handle 7 Stopper 11 Drum subunit 12 Developing subunit 12 Supporting part 13 Developing casing 14 Developing roller 15 Bearing hole 16 Bearing groove 17 Fixing lever 18 Drum protective cover 19a, 19b Photoconductor drum support shaft 21 Roller gear 22 Image forming unit 23b Developing roller support shaft 30 Color image forming apparatus 31 Main body base 32 Openable paper feed tray 33 Paper cassette 34 Upper lid 35 Paper discharge tray 36 Upper paper outlet 37 Upper lid Open / close switch 39 Operation panel 41 Paper transport belt (belt) 42 Drive roller 43 Follower roller 44 (44a, 44b, 44c, 44d) Photoconductor drum 45 Cleaner 46 Initializing charging roller 47 Writing head 48 Developing device (Developing sub-unit) G) 49 transfer sheet 51 support member 52 tension roller 53 suction roller 54 standby roller pair 55 paper feed guide path 56 feed roller pair 57 paper feed roller 58 fixing device 59 discharge roller pair 61 paper discharge path 62 discharge roller pair 63 Electrical part 65 Image forming unit 66 Drum sub-unit 67 Drum cover 68 Waste toner delivery pipe 69 Slot groove 70 Developer (toner) 71 (71a, 71b) Supporting part 72 Developing casing 73 Developing roller 74 Toner stirring member 75 Toner supply roller 76 Doctor blade 77 Scooping sheet 78 Waste toner receiving pipe 79 Collection bag 81 Bearing hole 82 Fixed lever 83a, 83b Developing roller support shaft 84a, 84b Photoreceptor drum support shaft 85 Transport pad 86 Delivery unit shutter 87 Protrusion ridge 88 Bearing groove 89 Lower opening Part 90 Porting member 91 Double-sided adhesive tape 92 Sponge 93 Handle 94, 95 Hand 96 Receiving port 97 Receiving section shutter 97-1 Opening 98 Support member 99 Rotating member 99a Locking claw 101 Groove

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Zenji Abe 2-229 Sakuragaoka, Higashiyamato-shi, Tokyo Inside Casio Electronics Co., Ltd. (72) Inventor Takao Yoto 2-229 Sakuragaoka, Higashiyamato-shi, Tokyo Casio Electronics Industries (72) Inventor Morinori Takaga 2-229 Sakuragaoka, Higashiyamato-shi, Tokyo Casio Electronics Co., Ltd. F-term (reference) 2H071 BA03 BA13 BA23 BA27 BA35 DA08 2H077 AD06 BA08 BA09 CA12 GA13

Claims (4)

[Claims] A developing unit for removably supporting an image-carrying sub-unit having an image carrier; a developing casing for accommodating a developer; And a developing roller for carrying and transporting an agent to develop a latent image formed on the image carrier, and integrated with the image carrier sub-unit by supporting the image carrier sub-unit on the support portion. A developing sub-unit configured to be detachably attached to an image forming apparatus main body as an image forming unit, comprising: an adhesive portion detachably adhered to an opening peripheral edge of the developing casing and a peeling handle at an end portion. A flexible sheet member that is attached to the unused developing sub-unit and that prevents the developer from leaking from between the peripheral edge of the opening and the peripheral surface of the developing roller. Do Image sub unit. 2. The developing sub-unit according to claim 1, wherein said flexible sheet member is made of a resin film. 3. When the flexible sheet member is adhered to the developing sub-unit, the peeling handle portion is attached to the supporting portion so that the developing sub-unit cannot support the developing unit. The developing sub-unit according to claim 1, wherein the sub-developing unit is arranged. 4. An image carrying sub-unit having an image carrier,
A supporting portion for detachably supporting the image carrying sub-unit, a developing casing for accommodating the developer, and a part of the peripheral surface being exposed from an opening of the developing casing to carry and carry the developer to the image carrier; A developing sub-unit having a developing roller for developing a latent image to be formed, and an image forming apparatus in which an image forming unit integrated by the support unit is detachably mounted, wherein the developing sub-unit is When not in use, in order to prevent the developer from leaking from between the peripheral edge of the opening and the peripheral surface of the developing roller, an adhesive portion and an end portion are detachably adhered to the peripheral edge of the opening of the developing casing. The peeling handle portion of the flexible sheet member having the formed peeling handle portion, the image carrying sub-unit and the developing sub-unit, if the flexible sheet member is not removed. An image forming apparatus, wherein the image forming apparatus is arranged on the supporting portion so that the image forming apparatus cannot be integrated.