JPH06161241A - Image forming device - Google Patents

Abstract

(57) [Summary] [Object] Regarding an image forming apparatus in which an electrostatic latent image forming section, a developing device, and a transfer section are arranged around an image forming body, while containing a sufficient amount of developer, The purpose is to realize the miniaturization of the device. [Structure] Latent image forming units 11 and 12 that form an electrostatic latent image on the image forming body 10 around the endless image forming body 10.
In the image forming apparatus, at least a developing device 2 for developing the electrostatic latent image of the image forming body 10 with a developer and a transfer portion 13 for transferring the developed image of the image forming body 10 to a medium are provided. The developing device 2 connects the developing unit 3 that conveys the developer to the image forming body 10, the stirring / replenishing unit 4 that stirs / supplements the developer, and the developing unit 3 and the stirring / supplementing unit 4. The stirring / replenishing section 4 is arranged in a direction away from the image forming body, and at least the developer of the stirring / replenishing section 4 is supplied to the developing section 3 by the coupling section 5. To do.

Description

Detailed Description of the Invention

(Table of Contents) Industrial Application Field of the Prior Art (FIG. 10) Problem to be Solved by the Invention Means for Solving the Problem (FIG. 1) Action Example (a) Description of the First Example ( 2 to 4) (b) Description of the second embodiment (FIG. 5) (c) Description of the third embodiment (FIG. 6) (d) Description of the fourth embodiment (FIG. 7) (e) ) Description of fifth embodiment (FIGS. 8 to 9) (f) Description of other embodiments Effects of the invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus in which an electrostatic latent image forming section, a developing device and a transfer section are arranged around an image forming body.

In image forming apparatuses such as copying machines, printers, and facsimile machines, latent image forming type recording apparatuses such as electrophotographic apparatuses are used in order to record plain paper. In this image forming apparatus, such as photosensitive drums are used. An electrostatic latent image is formed on an image forming drum, developed, and a toner image is transferred to a sheet to obtain a toner image on the sheet.

In such an image forming apparatus, a pre-charging device, an optical writing system, a developing device, a transfer device,
Since it is necessary to arrange a cleaner or the like, the arrangement space is limited, and measures for downsizing and colorization are required.

[0005]

2. Description of the Related Art FIG. 10 is an explanatory diagram of a conventional technique. For example, in an electrophotographic apparatus, as shown in FIG. 10, a photosensitive drum 10 is charged by a pre-charger 11, an optical image is exposed by a laser optical system (exposure source) 12, and electrostatic production according to the image is performed. The toner image is formed and toner-developed by the developing device 2, the toner image is transferred to the conveyed paper by the transfer device 13, and the paper is conveyed to the fixing device. Residual toner is cleaned by 15.

In such an image forming apparatus, the process unit 11 is provided around the photosensitive drum 10 and around the photosensitive drum 10.
It is necessary to arrange ~ 15, and the arrangement space is limited. Since the conventional developing device 2 has a configuration in which a required amount of developer is stored, the developer is agitated, and the developer is conveyed to the photosensitive drum 10, it is large and requires a large space.

[0007]

However, the prior art has the following problems. As shown in FIG. 10A, if a relatively large developing device 2 that stores a required amount of developer is used, the replacement cycle becomes long, but the photosensitive drum 10 also needs to be large, and the device is small. Becomes difficult.

For example, as disclosed in Japanese Examined Patent Publication No. 4-39073, even if the mixing case is arranged outside the developing case and the developer is stirred and replenished through the mixing case, the developing case Since the mixing case is provided in the axial direction of the developing roller, the arrangement space around the drum 10 is eventually required, which cannot be solved.

On the contrary, as shown in FIG. 10 (B), if the developing device 2 is made small, the size can be reduced, but the amount of stored developer becomes small, so that the developer replacement cycle and the toner replenishment replacement cycle are shortened. It becomes short and takes time and effort for the operator.

Similarly, in the color image forming apparatus, it is necessary to provide a plurality of developing devices for each color around the photosensitive drum 10, the developing device space is further limited, and it becomes difficult to arrange the developing devices.

Therefore, an object of the present invention is to provide an image forming apparatus capable of realizing a downsizing of the apparatus while accommodating a sufficient amount of developer. Another object of the present invention is to provide an image forming apparatus capable of facilitating arrangement of developing devices for respective colors for forming a color image.

[0012]

FIG. 1 shows the principle of the present invention. Claim 1 of the present invention provides an endless image forming body 1.
0, latent image forming portions 11 and 12 that form an electrostatic latent image on the image forming body 10, a developing device 2 that develops the electrostatic latent image of the image forming body 10 with a developer, and the image. In the image forming apparatus including at least the transfer unit 13 that transfers the developed image of the formed body 10 to the medium, the developing device 2 includes the developing unit 3 that conveys the developer to the image formed body 10, and the developer. It has a stirring / replenishing section 4 for stirring / replenishing, and a connecting section 5 for connecting the developing section 3 and the stirring / replenishing section 4, and the stirring / replenishing section 4 is moved away from the image forming body 10. It is characterized in that at least the developer in the stirring / replenishing section 4 is supplied to the developing section 3 by the connecting section 5.

According to claim 2 of the present invention, in claim 1,
The developing section 3 is provided with a rotating developer carrying member 30 for carrying the developer to the image forming body 10, and the connecting section 5 is provided from the stirring / replenishing section 4 to the developer carrying member 30. A first connecting portion 5a for supplying a developer,
A second connecting portion 5b for collecting the developer from the developer transport member 30 to the stirring / replenishing portion 4 is provided.

A third aspect of the present invention is based on the second aspect.
The first connecting portion 5a supplies the developer to the upstream side of the conveyed developer of the developer conveying member 30 of the developing portion 3, and the second connecting portion 5b supplies the developer of the developing portion 3. It is characterized in that the developer is arranged so as to be collected from the downstream side of the transported developer of the transport member 30.

A fourth aspect of the present invention is the introduction screw according to the second or third aspect, which introduces the developer supplied to the first connecting portion 5a into the developing section 3 in the axial direction of the developer conveying member 30. 31 and a discharge screw 32 for conveying the developer from the developer conveying member 30 to the second connecting portion 5b in the axial direction of the developer conveying member 30 and discharging the developer. .

According to a fifth aspect of the present invention, in the second, third or fourth aspect, the developing section 3 and the stirring / replenishing section 4 are provided with developer amount detecting sections 60 and 61, respectively, and both A control unit 6 for controlling the developer transport amount of the first and second connecting units 5a and 5b is provided, and the first and second connecting units 5a and 5a are provided in accordance with the outputs of the developer detecting units 60 and 61. It is characterized in that the developer transport amount of 5b is controlled.

A sixth aspect of the present invention is based on the first, second, third, fourth or fifth aspect, wherein the periphery of the image forming body 10 is:
A plurality of developing units 2 are provided, and the colors of the developers of the developing units 2 are made different.

[0018]

In the first aspect of the present invention, the developing device 2 is divided into the developing section 3 for only developing and the stirring / replenishing section 4 for stirring / replenishing, and the stirring / replenishing section 4 is separated from the image forming body 10. Arrange them in a direction away from each other, and connect them with the connecting portion 5,
Only the developing unit 3 needs to be arranged around the image forming body 10.

Therefore, the agitating / replenishing section 4 is attached to the image forming body 10.
Since it can be arranged in a direction away from, it is possible to reduce the space required for the developing device 2 around the image forming body 10,
The device can be miniaturized, a sufficient amount of developer can be accommodated, and the device can be miniaturized even if it is colorized.

In the second aspect of the present invention, the connecting portion 5 is constituted by the first connecting portion 5a for supplying the developer and the second connecting portion 5b for collecting the developer, and the stirring / replenishing portion is provided. 4 facilitates circulation of the developer between the developing unit 4 and the developing unit 3.

In claim 3 of the present invention, the first connecting portion 5a
Is arranged so as to convey the developer to the upstream side of the developer conveying member 30 of the developing unit 3 and to collect the developer on the downstream side of the developer conveying member 30 by the second connecting portion 5b. The replenished new developer can be supplied to the transport member 30, and the developer after development can be collected, which enables smooth development.

According to a fourth aspect of the present invention, the developing unit 3 has the first
Since the supply developer supplied from the connecting portion 5a is introduced in the axial direction of the developer conveying member 30 by the introduction screw 31, a new developer can be supplied in the axial direction of the developer conveying member 30 and the developer can be supplied by the discharging screw 32. It is possible to collect the old developer in the axial direction of the transport member 30 and to supply and collect the developer more stably.

In claim 5 of the present invention, the developing unit 3 and the stirring /
By providing the developer amount detection units 60 and 61 in the replenishment unit 4 and controlling the conveyance amount of the connection units 5a and 5b, the developer balanced between the development unit 3 and the stirring / replenishment unit 4 can be obtained. The amount can be secured.

According to the sixth aspect of the present invention, a plurality of developing units 3 can be arranged around the image forming body 10 and the stirring / supplying unit 4 can be arranged in another part. Body 1
Even if a plurality of developing units 3 are arranged around 0, it can be realized without increasing the size of the apparatus.

[0025]

【Example】

(a) Description of the First Embodiment FIG. 2 is a perspective view of the first embodiment of the present invention, FIG. 3 is a sectional view of the first embodiment of the present invention, and FIG. 4 is a description of the first embodiment of the present invention. It is a figure, and only the developing device is shown.

As shown in FIGS. 2 and 3, the developing unit 3 includes:
The developing roller 30 that faces the photosensitive drum 10 and rotates in the same direction as the rotating direction of the photosensitive drum 10 to convey the developer to the photosensitive drum 10, and the developer supplied from the first connecting portion 5a to the developing roller 30. Upstream (downstream) in the developer transport direction of
The introduction screw 31 that conveys the developing roller 30 in the axial direction is provided.

Further, in the developing section 3, the doctor blade 33 for regulating the thickness of the developer carried by the developing roller 30 and the developer passing through the photosensitive drum 10 of the developing roller 30 are peeled off from the developing roller 30 at the upper part. The scraper 34 and the developer scraped off by the scraper 34 are applied to the developing roller 3
A discharge screw 32 is provided for conveying in the 0 axial direction and discharging to the second connecting portion 5b.

The first connecting portion 5a has a conveying tube 50 for connecting the lower portion of the agitating / replenishing portion 4 and the lower portion of the developing portion 3, and by the supply screw 51 in the conveying tube 50,
The developer in the agitating / replenishing section 4 is conveyed to the lower portion of the developing section 3, which is on the upstream side of the developing roller 30.

The second connecting portion 5b is connected to the upper portion of the developing portion 3,
It has a conveying tube 52 that connects the upper part of the agitating / replenishing unit 4, and the recovery screw 53 in the conveying tube 52 causes the developer peeled from the developing roller 30 of the developing unit 3 to be agitated / replenishing unit 4. It is to be transported.

The stirring / replenishing section 4 includes a toner hopper 40 for storing toner, a toner replenishing roller 41 for replenishing the toner from the toner hopper 40, and a toner concentration for detecting the toner concentration of the stirring / replenishing section 4 by magnetic permeability. Sensor 4
3 and 3 are provided.

Further, as shown in FIGS. 2 and 4, the agitating / replenishing section 4 has four agitating screws 44 for agitating and charging the developer from the recovery screw 53 and the replenishing toner. 45, 46, and 47 are provided, and the developer after stirring is supplied to the developing unit 3 by the supply screw 51.

This operation will be described. As shown in FIG. 4 (A), the developer in the stirring / replenishing section 4 is the first connecting section 5a.
It is conveyed to the developing section 3 by the supply screw 51 through the conveying tube 50, is conveyed in the axial direction of the developing roller (magnet roller) 30 by the introducing screw 31, and is conveyed on the sleeve of the developing roller 30.

The height of the developer on the developing roller 30 is regulated by the doctor blade 33 to be used for development, and the developer which has been developed is scraped off from the sleeve of the developing roller 30 by the scraper 34. , Is collected by the discharge screw 32, and is guided to the transport tube 52 communicating with the developing unit 3.

The developer conveyed by the collecting screw 53 in the conveying tube 52 is circulated in the stirring / replenishing section 4 by the stirring screws 44 to 47, and the toner concentration is detected by the toner concentration sensor 43. The toner is replenished in accordance with the above, is conveyed while being stirred, and is guided to the developing unit 3 by the first connecting portion 5a.

In the process system using the photosensitive drum 10 having a diameter of 60 mm, in the conventional developing device, the amount of developer is
It is about 600 to 700 g, and as shown in FIG. 4 (B), its life is limited to 20,000 sheets at 4% printing rate of A4 paper, but when the developing device of this example is used, Stirring
The amount of developer in the replenishing section 4 can be freely designed in consideration of the size of the entire apparatus, for example, 2.5 Kg of developer can be accommodated and the replacement cycle can be extended to 300,000 sheets.

With this structure, the developing unit 3 and the stirring /
Since the replenishing section 4 is connected as a separate body, the developing section 3 having only the function of developing is arranged around the photosensitive drum 10 and the stirring / replenishing section 4 for containing the developer is provided at another arbitrary place. Therefore, if the required space of the developing unit 3 around the photosensitive drum 10 is the same, the amount of developer accommodated can be greatly increased, the replacement cycle of the developer can be greatly extended, and the development around the photosensitive drum 10 can be performed. The space required for the unit 3 can be reduced, and the device can be significantly downsized.

Further, in the color electrophotographic apparatus, it is possible to freely arrange the developing devices for the respective colors, and it is possible to reduce the size of the developing device space, or to extend the replacement period by increasing the developer amount.

Moreover, since the new developer is supplied to the upstream side of the developing roller 30 of the developing unit 3 and the developer after the development is recovered from the downstream side of the developing roller 30, efficient circulation of the developer is possible. Becomes

Furthermore, since the supplied developer is conveyed by the introduction roller 31 in the axial direction of the developing roller 30, the developing roller 30
Even if the developer is conveyed to a part of the developing roller 30, the developer can be uniformly dispersed in the axial direction, and the developer peeled off from the developing roller 30 is conveyed in the axial direction of the developing roller 30 to be collected. There is no risk of the developer remaining.

(B) Description of Second Embodiment FIG. 5 is a block diagram of the second embodiment of the present invention, showing a monochromatic electrophotographic printer.

In FIG. 5, the same components as those shown in FIGS. 1 to 4 and 10 are designated by the same symbols, and a pre-charger 11 and an exposure source 12 are provided around the photosensitive drum 10. A developing unit 3, a transfer unit 13, a charge removing unit 14 including a charge removing charger and a charge removing lamp, and a cleaner 15 are arranged.

The developing unit 2 includes a developing unit 3 arranged around the photosensitive drum 10 and a stirring / discharging unit arranged at other positions.
It has a replenishing part 4 and is connected by connecting parts 5a and 5b.

The developing section 3 has a pair of developing rollers 30, and the stirring / replenishing section 4 has a toner hopper 40 for containing toner, a toner replenishing roller 41 for supplying the toner from the toner hopper 40 to the stirring area, and a stirring roller. 44-47.

The developing section 3 is connected to the stirring / replenishing section 4 by a pair of connecting portions 5a and 5b.
Similar to the embodiment shown in FIGS. 2 to 4, a and 5b respectively have carrier tubes 50 and 52, a supply screw 51, and a recovery screw 53, and supply and recover the developer.

The developing unit 3 and the agitating / replenishing unit 4 are provided with developer amount sensors 60 and 61 each composed of a magnetic sensor for detecting the developer amount. As shown in FIG. 1B, the screw 53 is driven by separate motors 62 and 63.

The developer transport control section 6 drives and controls the motors 62 and 63 based on the outputs of the developer amount sensors 60 and 61, and keeps the developer amount of the developing section 3 constant, while
And the amount of developer in the stirring / replenishing section 4 are kept in balance.

That is, when the developer amount sensor 60 detects that the developer amount in the developing unit 3 has decreased, the control unit 6
Increases the rotation speed of the motor 62 of the supply screw 51 to increase the developer supply amount by the supply screw 51.

On the contrary, when the developer amount sensor 60 detects that the developer amount in the developing unit 3 has increased, and the developer amount sensor 61 detects that the developer amount in the stirring / replenishing unit 4 is small. The rotation speed of the motor 63 of the recovery screw 53 is increased to increase the amount of developer recovered by the recovery screw 53.

In this way, the developer amount in the developing unit 3 and the stirring / replenishing unit 4 are controlled so as to maintain a balance.
Further, since the developing unit 3 and the stirring / replenishing unit 4 are separated, a large amount of developer can be stored in the stirring / replenishing unit 4, the replacement life can be greatly extended, and the arrangement space around the photosensitive drum 10 can be increased. It can be reduced, the photosensitive drum 10 etc. can be made small,
The size of the device can be reduced.

(C) Description of Third Embodiment FIG. 6 is a block diagram of the third embodiment of the present invention, showing a color electrophotographic printer having one drum.

In FIG. 6, the same components as those shown in FIGS. 1 to 5 and 10 are designated by the same symbols, and a pre-charger 11 and each color (cyan, cyan, Exposure Sources 12-1 to 1 for Magenta, Yellow, Black)
2-4, developing units 3-1 to 3-4 for each color (cyan, magenta, yellow, black), transfer unit 13, static eliminator 14 including a static eliminator and a static eliminator, and a cleaner 1
5 are arranged.

Each of the developing devices 3-1 to 3-4 includes the photosensitive drum 1.
0, and developing units 3-1 to 3-4 arranged around 0, and stirring / replenishing units 4-1 to 4-4 arranged at other positions, and connecting units 5-1 to 5- They are connected by 4.

The developing units 3-1 to 3-4 have a pair of developing rollers 30, and the stirring and replenishing units 4-1 to 4-4 are toner hoppers 40-1 to 40-4 for containing toner, It has toner replenishing rollers 41-1 to 41-4 for supplying toner from the toner hoppers 40-1 to 40-4 to the stirring area and stirring rollers 44-1 to 47-4.

The developing sections 3-1 to 3-4 are connected to the stirring / replenishing sections 4-1 to 4-4 by a pair of connecting sections 5-1 to 5-4, and a pair of connecting sections 5-. 1 to 5-4 are transfer tubes 50 and 52, respectively, as in the embodiment of FIGS.
It has a supply screw 51 and a recovery screw 53, and supplies and recovers the developer.

Developing units 3-1 to 3-4 and stirring / replenishing unit 4-
1 to 4-4 are developer amount sensors 60-1 to 60-, each of which is composed of a magnetic sensor for detecting the developer amount.
4, 61-1 to 61-4 are provided, and each of the supply screw 51 and the recovery screw 53 has separate motors 62-1 to 62-4, 63 as shown in FIG. 1 (B).
It is driven by -1 to 63-4.

The developer transport controller 6 outputs the respective developer amount sensors 60-1 to 60-4 and 61-1 to 61-4 to output the respective motors 62-1 to 62-4 and 63-1 to 63-3. -4
Is controlled to keep the amount of the developer in the developing units 3-1 to 3-4 constant, and the developing units 3-1 to 3-4 and the stirring / replenishing unit 4-
The balance with the developer amount of 1 to 4-4 is maintained.

That is, the developer amount sensors 60-1 to 60-4
When it is detected that the developer amount in the developing units 3-1 to 3-4 has decreased, the control unit 6 increases the rotation speed of the motor 62 of the supply screw 51 to increase the developer supply amount by the supply screw 51. Let

On the contrary, the developer amount sensors 60-1 to 60-4
It is detected that the developer amount in the developing units 3-1 to 3-4 has increased, and the developer amount sensors 61-1 to 61-4 detect the developer amounts in the stirring / replenishing units 4-1 to 4-4. When it is detected that the amount of developer is small, the rotation speed of the motor 53 of the recovery screw 53 is increased to increase the amount of developer recovered by the recovery screw 53.

In this way, the developing units 3-1 to 3-4
And the amount of developer in the stirring / replenishing units 4-1 to 4-4 are controlled to be balanced. In addition, the developing units 3-1 to 3 for each color
4 and the stirring / replenishing units 4-1 to 4-4 are separated,
A large amount of each color developer can be stored in the stirring / replenishing units 4-1 to 4-4, the replacement life can be significantly extended, and the arrangement space around the photosensitive drum 10 can be reduced, and the photosensitive drum 10 and the like can be downsized. Therefore, the device can be downsized even if it is made into a color.

(D) Description of Fourth Embodiment FIG. 7 is a block diagram of the fourth embodiment of the present invention, showing a color electrophotographic printer having a drum for each color.

In FIG. 7, the same components as those shown in FIG. 6 are represented by the same symbols, and the photosensitive drums 10-1 to 10 for each color (cyan, magenta, yellow, black) are shown.
-4 are arranged vertically.

Around the photosensitive drums 10-1 to 10-4, front chargers 11-1 to 11-4 and an exposure source 1 for each color (cyan, magenta, yellow, black) are provided.
2-1 to 12-4, developing units 3-1 to 3-4 for each color (cyan, magenta, yellow, black), and transfer unit 13
-1 to 13-4 and a static eliminator 14-1 including a static eliminator lamp
14-4 and cleaners 15-1 to 15-4 are arranged.

Each of the developing devices 3-1 to 3-4 is a photosensitive drum 1.
Developing units 3-1 to 3 arranged around 0-1 to 10-4
-4 and the stirring / replenishing section 4-arranged at other positions
1 to 4-4 and are connected by the connecting portions 5-1 to 5-4.

The developing units 3-1 to 3-4 have a developing roller 30 and are connected to the stirring / replenishing units 4-1 to 4-4 by a pair of connecting units 5-1 to 5-4. , A pair of connecting parts 5-
1 to 5-4 respectively have transport tubes 50 and 52, a supply screw 51 and a recovery screw 53, and supply and recover the developer, as in the embodiment shown in FIGS.

On the other hand, the paper transport path is guided from the paper hopper 16 to the lower portion of the apparatus, and the photosensitive drums 10-1 and 10- are connected.
After passing through the vertical conveying paths 2, 10, 3 and 10-4, the direction is changed to the fixing device 17 at the upper part of the apparatus and reaches the sheet stacker 18.

In such an apparatus, the cyan toner image is transferred to the paper of the paper hopper 16 by the photosensitive drum 10-1, and the magenta toner image is transferred to the photosensitive drum 10-2. At -3, the yellow toner image is transferred, and finally at the photosensitive drum 10-4, the black toner image is transferred.

Then, the sheet on which the toner images of these respective colors have been transferred is fixed with the toner image by the fixing device 17, and is stored in the sheet stacker 18. In this apparatus, only the developing units 3-1 to 3-4 need to be arranged as developing units around the photosensitive drums 10-1 to 10-4. The device can be made compact and can be brought close to each other, and the device can be made compact and the transport path can be shortened.

Further, since the stirring / replenishing sections 5-1 to 5-4 can be arranged in the empty space of the apparatus, a large amount of toner can be accommodated and the replacement life can be greatly extended. Further, in this example, since the stirring / replenishing units 5-1 to 5-4 are provided on the right side surface of the apparatus, the toner of each color can be exchanged on the right side surface, and the cleaner 15-1 is provided on the upper side thereof. ~ 15-4
Since the waste toner recovery pack is provided, the recovery pack can be replaced on the right side surface and the mounting efficiency can be improved.

Moreover, the optical units 12-1 to 12-12 are provided between the first connecting portion 5a and the second connecting portion 5b of the connecting portions 5-1 to 5-4 (see FIGS. 2 to 4). -4 can be arranged, so that the periphery of the photosensitive drum can be used more efficiently.

(E) Description of the Fifth Embodiment FIG. 8 is a block diagram of the fifth embodiment of the present invention, and FIG. 9 is a perspective view of the fifth embodiment of the present invention.

In FIGS. 8 and 9, the same components as those shown in FIGS. 2 to 4 are designated by the same symbols. In this embodiment, the structure of the connecting portion 5 is different from that of FIG. 2 to FIG. 4, and a plurality of conveying magnetic rollers 54 which are the same as the developing roller 30 of the developing portion 3 are arranged side by side.

That is, as shown in FIG.
The connecting section 5 from the developing section 3 to the developing section 3 is configured to be integral with the developing section 3 within the width of the developing section 3. As shown in FIG. 8, the connecting portion 5 alternately connects the magnetic transport roller 54 and the scraper / partition plate 55 from the stirring / replenishing portion 4 to the developing roller 30.
Up to several are installed side by side. This transport magnetic roller 5
4 is the same width as the developing roller 30,
Rotate in the same direction as.

Therefore, the developer in the agitating / replenishing section 4 is conveyed in the direction of the developing roller 30 by the rotation of the conveying magnetic roller 54, scraped off by the scraper / partition plate 55, and then conveyed to the next conveying magnetic roller 54. Sequentially passed, developing roller 30
Reach.

On the other hand, the developer after development by the developing roller 30 is scraped off by the scraper / partition plate 55 and transferred to the carrying magnetic roller 54. Similarly, the developer on the carrying magnetic roller 54 is scraped by the scraper. It is scraped off by the dual partition plate 55, passed sequentially to the next transport magnetic roller 54, and returned to the stirring / supply unit 4 by the scraper 56.

In this way, by using the transport magnetic roller 54 and the scraper / partition plate 55, the new developer can be transported under the magnetic roller 54 and the developer after development can be transported over the upper portion. , A supply path and a recovery path can be formed.

The developer returned by the scraper 56 is
The toner is mixed with the toner supplied from the toner hopper 40 by the toner replenishing roller 41 and stirred by the stirring screw 48,
Supplied as a new developer.

With such a structure, the connecting portion 5 can convey the developer in parallel by the width of the developing roller 30, and the developer can be conveyed in the axial direction of the developing roller 30 as shown in FIGS. In addition to eliminating the need for a transporting mechanism, since the direction is not changed, a stable developer flow is possible.

Further, since it rotates in the same direction as the developing roller 30, the drive system can be made common and can be driven by gear connection, so that the structure is simple. Further, the magnetic roller 54 is the developing roller 3
Since the configuration is the same as 0, the transport roller can be shared.

(F) Description of Other Embodiments In addition to the above embodiments, the present invention can be modified as follows. Although the image forming apparatus has been described as an electrophotographic mechanism in the above-described embodiments, it may be used as a printing mechanism (for example, an electrostatic recording mechanism) that forms a toner image.

Although the image forming apparatus has been described as a printer,
It may be another image forming apparatus such as a copying machine or a facsimile. The developer may be a two-component system or a one-component system, and in the case of a one-component system, the connecting portion may be only the developer supply.

The device of the fifth embodiment may be applied to the color image forming apparatus of the third and fourth embodiments. Although the present invention has been described with reference to the embodiments, various modifications are possible within the scope of the gist of the present invention, and these modifications are not excluded from the scope of the present invention.

[0082]

As described above, according to the present invention,
It has the following effects. Since the developing unit and the stirring / replenishing unit are separated and connected by the connecting unit, a large amount of developer can be stored and the replacement cycle can be greatly extended even if the developing unit surrounding the image forming body is limited in space. .

Further, the space for disposing the developing unit around the image forming body can be reduced, and the size of the apparatus can be reduced. Since the stirring / replenishing section can be placed at any position,
Arrangement of the developing device becomes easy.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a perspective view of the first embodiment of the present invention.

FIG. 3 is a sectional view of the first embodiment of the present invention.

FIG. 4 is an explanatory diagram of the first embodiment of the present invention.

FIG. 5 is a configuration diagram of a second embodiment of the present invention.

FIG. 6 is a configuration diagram of a third embodiment of the present invention.

FIG. 7 is a configuration diagram of a fourth embodiment of the present invention.

FIG. 8 is a configuration diagram of a fifth embodiment of the present invention.

FIG. 9 is a perspective view of a fifth embodiment of the present invention.

FIG. 10 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 2 developing device 3 developing unit 4 stirring / replenishing unit 5, 5a, 5b connecting unit 6 developer transport control unit 10 photosensitive drum (image forming drum) 11 pre-charger 12 laser optical system 13 transfer unit 14 charge eliminating unit 15 cleaner 30 development Rollers 50, 52 Conveyor tube 51 Supply screw 53 Recovery screw

Claims (6)

[Claims] 1. A latent image forming section (11, 12) for forming an electrostatic latent image on the image forming body (10) around the endless image forming body (10), and the image forming body (10). Developing device (2) for developing the electrostatic latent image of (1) with a developer, and the image forming body (10).
An image forming apparatus provided with at least a transfer part (13) for transferring the developed image of the above to a medium, the developing device (2) is a developing part (3) for conveying the developer to the image forming body (10). And stirring and replenishing the developer
A replenishing section (4) and a connecting section (5) for connecting the developing section (3) and the stirring / replenishing section (4) are provided, and the stirring / replenishing section (4) is connected to the image forming body ( An image forming apparatus, which is arranged in a direction away from 10), and supplies the developer of at least the stirring / replenishing section (4) to the developing section (3) by the connecting section (5). 2. The image forming body (1) is attached to the developing section (3).
0) is provided with a rotating developer transporting member (30) for transporting the developer, and the connecting part (5) is connected to the developer transporting member (30) from the stirring / replenishing part (4) to develop the developer. It has a first connecting part (5a) for supplying the developer and a second connecting part (5b) for collecting the developer from the developer carrying member (30) to the stirring / replenishing part (4). The image forming apparatus according to claim 1, wherein: 3. The first connecting portion (5a) supplies the developer to the upstream side of the conveyed developer of the developer conveying member (30) of the developing portion (3), and the second connecting portion (5a). Part (5b)
The image forming apparatus according to claim 2, wherein the image forming apparatus is arranged so as to collect the developer from the downstream side of the conveyed developer of the developer conveying member (30) of the developing section (3). 4. An introducing screw (31) for introducing the developer supplied to the first connecting part (5a) into the developing part (3) in the axial direction of the developer carrying member (30), and the developing device. A discharge screw (32) for conveying the developer from the developer conveying member (30) to the second connecting portion (5b) in the axial direction of the developer conveying member (30) and discharging the developer is provided. The image forming apparatus according to claim 2 or 3, which is characterized in that. 5. A developer amount detecting section (60, 61) is provided on the developing section (3) and the stirring / replenishing section (4), and the first and second connecting sections (5a, 5a, 5b) is provided with a control unit (6) for controlling the developer transport amount, and the development of the first and second connection units (5a, 5b) is performed according to the output of the developer detection unit (60, 61). The image forming apparatus according to claim 2, wherein the amount of agent transportation is controlled. 6. The image forming body (10) is provided with a plurality of the developing sections (2) around the image forming body (10), and the colors of the developers of the developing sections (2) are made different from each other. Alternatively, 2 or 3 or 4 or 5 image forming apparatus.