JPH1069167A - Image forming device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To ensure reliable toner transfer with a simple and low-cost device configuration, and to transfer toner (toner discharge unit)
Provided is an image forming apparatus having a configuration for transferring toner that can also solve the problem of toner scattering in the image forming apparatus. In an image forming apparatus according to the present invention, toner supply means (screw pump) having a rotor and a stator is supplied, and air is supplied to toner moving in the toner supply means to fluidize the toner. Toner supply device (toner supply device 3)
50, a collected toner transfer device 400), and toner transfer means (flexible pipes) 352, 402 serving as a transfer path of the toner sent from the toner transfer device. The suction unit is configured to be connected to the space of the connection destination of the toner transfer unit (the toner supply unit 200B of the developing device 200).

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 such as an electrophotographic printer, a facsimile or a copying machine using a two-component developer or a one-component developer, and further supplies toner to the developing device. A toner supply device, a cleaning device for an image forming body (a photoreceptor, an intermediate transfer body, etc.), and a cleaning device for a transfer paper transporting body are provided. The toner is transferred from the toner supply device to the developing device, and the toner collected by the cleaning device. The present invention relates to an image forming apparatus having a configuration for transferring a toner to a collected toner bottle or a developing device.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus such as a printer, a facsimile, or a copying machine using a two-component developer or a one-component developer, a developing unit of the developing device is provided separately from the developing device. The following technology is related to a toner supply device that supplies toner from a stored toner storage unit. In a developing device using a two-component developer, a technique is used in which a toner storage section and a developing section are connected by a pipe, and the toner is supplied to the developing section by transferring the toner to the developing section by a coil screw provided inside the pipe. No. 61-188564, etc.). A technology in which a toner storage container is provided at a position close to a developing unit, and toner is supplied from the toner storage container to the developing unit mainly by gravity.

Further, there is provided a cleaning device for cleaning and recovering residual toner after image formation (residual toner on an image forming body such as a photoreceptor or an intermediate transfer body, and residual toner on a transfer paper transporting body such as a transfer belt). In the provided image forming apparatus, there are the following techniques regarding a collected toner transfer device that transfers toner from the cleaning device to a collected toner storage unit or a developing device provided separately from the cleaning device. The collected toner discharge section of the cleaning device and the collected toner storage means provided separately from the cleaning device are connected by a pipe, and the collected toner is collected by a coil screw (or a coiled collection spring) provided inside the pipe. For transferring the toner to the collecting toner storage means (Japanese Patent Laid-Open No.
6-46281, JP-A-56-57076, etc.). A technique in which a collected toner storage means is provided at a position close to a collected toner discharge section of a cleaning device, and the collected toner is transferred to the collected toner storage means mainly by gravity (Japanese Patent Application Laid-Open No. 58-54369).

[0004]

In an image forming apparatus using an electrophotographic process, toner supply to a developing unit,
In order to collect the waste toner or recycle the toner, the conveyance of the toner is indispensable. However, in the conventional toner transfer device, as a transfer unit, the toner is transferred by a pipe and a toner transfer unit that transfers the collected toner by a coil screw provided inside the pipe, or the collected toner is naturally dropped by gravity. Toner transfer means has been used.

In these toner transfer means, it is necessary to provide a coil screw as close as possible to the developing device and the collected toner storage means. In order to ensure the reliable rotation of the coil screw, a linear transfer is preferable. In addition, it is necessary to secure a transfer path having a large curved transfer (a bent transfer path is not possible), and it is desirable that the toner discharge side is lower than the toner feed side (from the horizontal direction). There is. Further, in the conventional toner transfer device, it is difficult to reduce the load of the coil screw (large friction load with the pipe), transfer over a long distance, increase the size of the components, complicate the device configuration and ensure durability, and There is a problem that operability during maintenance of the apparatus is difficult. In addition, there is a problem in that the size and complexity of the image forming apparatus and the cost of the main body increase due to restrictions on the mounting position of the toner transfer device.

Therefore, in order to solve the above-mentioned problem, the applicant of the present invention has firstly constructed a simple and inexpensive apparatus for reliably transferring toner for supplying toner to a developing unit and collecting waste toner. A screw pump having a rotor for moving toner in the axial direction by rotation and a fixed stator arranged to enclose the rotor and having a passage for the rotor and in contact with and engaging with the rotor, as a toner transfer means capable of being rotated. There has been proposed an image forming apparatus including a toner transfer device including an air supply unit for supplying air for fluidizing toner moved by the screw pump to the screw pump (Japanese Patent Laid-Open No. 7-2).
19329, Japanese Patent Application No. 7-89697, Japanese Patent Application No. 7
-339182).

In this toner transfer device, by using the screw pump and the air supply means for supplying air to the screw pump, the toner can be transferred to the developing device and the collected toner storage unit in a state of a mixture with air. As a result, a flexible pipe or the like can be used for the transfer path, the degree of freedom of the transfer path is large, and the transfer load is small, so that reliable toner transfer can be achieved with a simple and low-cost apparatus configuration. .

In the image forming apparatus using the toner transfer device as described above, the toner transfer path can be constituted only by a flexible pipe (tube) member. In comparison with this, there is a great merit that the degree of freedom in layout is remarkably high. However, in this toner transfer device, it is necessary to fluidize the toner by air mixing in order to stabilize the transfer of the toner. As a result, the transfer destination (toner discharge unit) of the supplied toner and the collected toner is such that the toner is mixed with air. Therefore, there is a problem that toner is scattered in the toner discharge unit due to an increase in internal pressure at a transfer destination (toner discharge unit) of a developing device or the like.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and makes it possible to reliably transfer toner with a simple and low-cost apparatus configuration, and to prevent toner scattering at a toner transfer destination (toner discharge unit). It is an object of the present invention to provide an image forming apparatus having a configuration for transferring toner, which can eliminate the problem.

[0010]

According to a first aspect of the present invention, an electrostatic latent image is formed on an image forming body, and the latent image is formed by a toner in a developer of a developing device. In an image forming apparatus using an electrophotographic process of developing and visualizing an image and transferring the visible image to a transfer material to form an image, a rotor that rotates to move toner in an axial direction, and the rotor Sending means (screw pump) comprising: a stationary stator that is arranged so as to include the stationary member, constitutes a passage of the rotor, and comes into contact with the rotor.
And a toner transfer device including air supply means for supplying and fluidizing air to the toner moving in the toner sending means, and a transfer path of the toner sent from the toner transfer device. And a toner transfer device, wherein the air suction portion of the air supply device in the toner transfer device is connected to a space at a connection destination (toner discharge portion) of the toner transfer device. The transfer is used for at least one of supply, recovery, and recycling of the toner in the electrophotographic process.

That is, in the image forming apparatus according to the first aspect of the invention, the toner transfer device is provided with a toner sending means (screw pump) and an air supply means for supplying air to the toner sending means, so that the toner is transferred to the toner transferring device. Can be transferred in a state of a mixture with air, so that a flexible pipe or the like can be used as a toner transfer means serving as a transfer path, and the degree of freedom of the transfer path is small, and the transfer load is small. Can be transferred with a simple and low-cost device configuration. Since the air suction unit of the air supply unit in the toner transfer device is connected to the space of the connection destination (toner discharge unit) of the toner transfer unit (flexible pipe or the like), the air is forcibly discharged by the toner discharge unit. By suction, an increase in air pressure at the toner transfer destination can be reduced, and toner scattering is reduced. In addition, since the air suction also serves as an air suction unit of an air supply unit that supplies air required by the toner delivery unit of the toner transfer device, an optimal air suction amount can be obtained.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, only the toner is separated from a mixture of the transferred toner and air at a connection destination (toner discharge portion) of the toner transfer means. It has a toner collecting means for collecting, the toner collecting means has a conical shape, the toner transfer means is connected to an upper side surface thereof, and an air suction part in the air supply means is connected to an upper surface thereof, The lowest part is used as a toner discharge port.

In the configuration of the first aspect, the air suction portion of the air supply means in the toner transfer device is connected to the toner transfer means (a flexible pipe or the like) (toner discharge portion).
In the image forming apparatus according to claim 2, since the toner is mixed during suction of air due to the configuration connected to the space, the reliability is reduced due to clogging or the like in the path of the air supply means. The toner and air are separated by toner collecting means provided in the toner discharging section, and the separated toner falls by gravity to the toner discharging port provided at the lowest part of the toner collecting means, and the air collects the toner. Since the air is supplied to the air supply unit through the air suction unit provided on the upper surface of the collection unit, the amount of toner flowing into the air supply unit can be reduced, and the reliability of the toner transfer device can be improved.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the air suction section of the air supply means is connected to a connection destination (toner discharge section) of the toner transfer means via a filter. It is characterized by being connected.

In the configuration of the first aspect, the air suction portion of the air supply means in the toner transfer device is connected to the toner transfer means (a flexible pipe or the like) (toner discharge portion).
Because of the configuration connected to the space, toner is mixed in at the time of air suction, and the reliability is deteriorated due to clogging or the like in the path of the air supply means. Although there is a possibility that the toner may be mixed in the image forming apparatus, the filter is provided in the air suction portion of the air supply means.
Since the toner and the air are reliably separated and only the air is sucked into the air suction portion of the air supply means, the toner can be prevented from flowing into the path of the air supply means, and the reliability of the present toner transfer device is improved. .

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail based on illustrated embodiments. FIG. 1 is a schematic configuration diagram of an image forming apparatus showing one embodiment of the present invention. In FIG. 1, this image forming apparatus is an example of a copying machine, and the copying machine main body 100 includes an exposure unit 20, an image forming unit 30, and a paper feeding unit 40 for forming an image by a conventionally known electrophotographic method. It is configured. The exposure unit 20 includes a light source 22 for irradiating a document placed on the contact glass 21 with light, and mirrors 23, 24, 25, and 27 for exposing a reflected light image from the document onto the photoconductor 150. , 28, 29 and a lens 26. The image forming unit 30 includes a drum-shaped photoconductor 150, a charging unit 160 disposed around the photoconductor 150, and a developing device 20.
0, a transfer belt unit 250, a photoconductor cleaning unit 300, a fixing unit 500, and the like. The paper supply unit 40 is provided with a plurality of paper supply cassettes containing transfer papers of various sizes.
In the illustrated example, an analog optical system is shown as the exposure unit 20, but a laser scanning optical system including a laser light source and a deflector is used instead, If optical writing is performed on 150, a configuration of a laser printer is obtained, and if a document reading device is further provided, a configuration of a digital copying machine or a facsimile is obtained.

In FIG. 1, when the image forming operation is started, the photosensitive member 150 is charged by the charging unit 160, the original image from the exposure section 20 is exposed, and an electrostatic latent image is formed. This electrostatic latent image is developed with the toner of the developer (two-component developer or one-component developer) of the developing device 200, and a toner image is formed on the photoconductor 150. Photoconductor 1
The toner image on the sheet 50 is fed from the sheet feeding unit 40 and is transferred to a transfer sheet fed to a transfer position (a nip portion between the photoconductor 150 and the transfer belt 255) via the registration roller 170. Then, the transfer paper on which the toner image has been transferred is conveyed to the fixing unit 500 by the transfer belt 255 of the transfer belt unit 250, and the toner image is fixed on the transfer paper by the fixing unit 500.
The paper is discharged to the paper discharge tray 600 via the “0”. On the other hand, the photoconductor 150 after the transfer of the toner image is cleaned by the photoconductor cleaning unit 300, and the residual toner is removed and collected. Further, the transfer belt 255 after the transfer of the transfer paper is also cleaned by a transfer belt cleaning device 251 which is a cleaning means attached to the transfer belt unit 250, and residual toner is removed and collected. The cleaning method of the photoconductor cleaning unit 300 and the transfer belt cleaning device 250 includes a blade cleaning method, a roller cleaning method, a brush cleaning method, and the like.

The copying machine according to the present embodiment is an image forming apparatus which realizes the supply, collection and recycling of toner based on the structure of claim 1 and which simultaneously reflects the claims 2 and 3. Supply device 350 including a toner storage container that stores the toner and a toner transfer device that supplies the toner to the developing device 200, and collected toner that transfers the collected toner collected by each cleaning unit to the developing device 200 for recycling A transfer device 400 is provided. Hereinafter, the configuration of supply, collection, and recycling of toner will be described in detail.

A toner supply device 350 including a toner transfer device including a toner delivery unit and an air supply unit is configured as an independent unit separately from the copying machine main body 100. Copier body 150 via toner supply pipe 352
Is supplied to the developing device 200.

A recovered toner transfer device 400 including a toner sending means and an air supply means is installed on the back of the copying machine main body 100, and the photosensitive member cleaning unit 30 is provided.
0 and connected to the collected toner discharge unit from the transfer belt cleaning device 251. The collected toner 401 is supplied to the developing device 200 of the copying machine main body 100 via a collected toner transfer pipe 402 which is a toner transfer unit.

FIG. 2 shows an example of the structure of the developing device 200. Here, the developing device 200 shows an example using a two-component magnetic brush developing system. In FIG. 2, a developer 202 stored in a casing 201 of a developing device 200 includes a stirring roller 203, a developing sleeve 204,
The developer is circulated and transferred by the development agitator 205 to perform the development process. To supply toner to the developing unit, toner is transferred from one end of the developing device 200 to the center by an agitator 206 provided in a toner transfer container 210 of the toner supply unit 200B. 208 causes the toner 207 to be
The developer is dropped and supplied to the 0 A developing agitator 205. Then, the mixture is agitated and mixed with the developer 202 by the development agitator 205. Although the developing device using the two-component magnetic brush developing system is used here, the use of the one-component developing system does not affect the present invention at all.

Next, FIGS. 3, 4 and 5 show examples of the structure of the toner supply section 200B in the developing device 200. FIG. In FIG. 3, the toner 351 (or the collected toner 401) transferred from the toner supply device 350 (or the collected toner transfer device 400) is transferred to a toner collecting device 20 described later.
9, the toner transfer container 21 of the toner supply unit 200B
0 through the opening 211 provided at one end of the developing device 20.
0 is supplied. In the developing device, the toner is transferred to the central portion of the developing device by the agitator 206 having a transfer screw shape, and is dropped and supplied to the developing agitator 205 of the developing unit 200A by the toner supply roller 208 as described above. Is stirred and mixed with the developer 202.

4 and 5, the toner 351 (or the recovered toner 401) transferred from the toner supply device 350 (or the recovered toner transfer device 400) described above.
Is transported in the state of a mixture of toner and air,
If the toner is supplied to the developing device 200 as it is, the toner is blown out from the developing device 200 by air pressure, which causes problems such as contamination inside the device, image damage due to dust, occurrence of an abnormal image, and safety and health concerns. In order to prevent these troubles, the toner replenishing unit 200B includes a toner collecting device 20.
9 are incorporated. This toner collecting device 209 is
Developing device 200 that separates toner and air and uses only toner
For replenishing the toner replenishing unit 200B of
As a basic collecting method of the toner collecting device 209, a conventionally known cyclone method is used.

The mixture of the toner and the air transferred to the toner collecting device 209 is supplied to the inlet 213a provided at the upper portion of the hopper 212 having a small conical shape on the lower side.
From 213b, it is transferred into the hopper 212. And it rotates along the hopper inner wall. During this time, the heavy toner sediments, is collected at the lower part of the hopper, and is supplied into the developing device by the agitator 206 through the opening 211 provided at one end of the toner transfer container 210 through the toner discharge hole 214. .

On the other hand, the air separated from the toner passes through a filter 216 through a discharge hole of an air discharge member 215 provided in the upper part of the hopper, and a toner supply device 350 described later connected via a joint 217 and a recovery device. Air supply means 367, 415 in toner transfer device 400
By air transfer pipes 371 and 419 for air suction of
The air is supplied to the air supply means 367, 415.

Therefore, the toner is not only stably supplied to the developing device 200, but also the air-fuel mixture is reduced in pressure, so that the toner does not scatter from the developing device. In particular, since the decompression of the air is forcibly performed by using the air supply means of the toner supply device 350 and the collected toner transfer device 400 described later, stable performance can be obtained. Further, since the toner and the air are almost separated by the toner collecting device 209 and the filter 216, there is no fear that the toner is mixed into the air supply means and a failure such as clogging occurs.

In this case, the toner separating / collecting means according to the second aspect and the filter according to the third aspect are provided to reduce the mixing of toner into the air supply means. In a place to be a connection destination of, for example, an upper surface portion of the toner transfer container 210, or the like,
Even if the air transfer pipes 371 and 419 are directly connected, the basic performance of the present invention is maintained. However, in this case,
Since the toner is mixed with the air, the air supply means is required to have a performance capable of withstanding the toner.

The introduction hole 213a communicates with the toner supply device 350 through a toner supply pipe 352,
Reference numeral 13b communicates with the collected toner transfer device 400 via a collected toner transfer pipe 402. Therefore, in addition to the supply of new toner from the toner supply device 350, the toner collected from each of the cleaning devices described below also
00 is supplied.

FIGS. 6 and 7 show examples of the structure of the toner supply device 350. FIG. 6, a main body 353a of the toner container 353 is formed by bending a plate-like member into a substantially U-shape, and side plates 354 and 355 are attached to both sides thereof via a seal group 356. Top plate 353b
Is attached. The toner 351 is supplied to an opening 357 provided in a part of the top plate 353b of the toner container 353.
Is loaded and replenished. Then, the toner storage container 35
The toner 351 in the toner transfer unit 362 is reliably transferred to the toner delivery unit 362 of the toner transfer device by the weight of the toner itself, the agitator 360 rotated by the drive motor 358 via the drive member 359, and the horizontal transport screw 361. Has become.

Next, the toner delivery means 362 of the toner transfer device in the toner supply device 350 will be described. As shown in FIG. 6 and FIG.
A screw pump called a so-called mono pump, which is a conventionally known powder pump, is used. This is basically composed of a rotor 363 that moves toner in the axial direction by rotating, and a fixed stator 364 that is made of an elastic member such as a rubber material and surrounds the rotor 363. It is held by a holder 365.
Further, the rotor 363 is engaged with the horizontal transport screw 361, and the other end of the horizontal transport screw 361 is engaged with the drive motor 358 via a drive member 359 composed of a gear or the like.

Rotor 36 in toner delivery means 362
3. The size of the stator 364 and the number of rotations of the rotor 363 are selected according to the toner transfer distance and transfer amount. The drive motor 358 is connected to the toner transfer container 2 of the developing device 200.
Toner near-end detector 21 provided on one end surface of reference numeral 10
Based on the information of No. 8, the drive is controlled by a CPU of a control device described later.

Next, the air supply means of the toner transfer device in the toner supply device 350 will be described. There is a gap of about 1 mm between the outer side surface of the stator 363 and the inner side surface of the holder 365 in the toner sending means 362, and communicates with the toner passage. An air supply port 366 is provided so as to blow into the toner passage from the gap, and this air supply port 366 communicates with an air discharge port 368 provided in air supply means 367 composed of an air pump via an air transfer pipe 369. doing.

When activated, the air supply means 367 blows air at a rate of about 0.5 to 2.0 liters / minute into the toner passage of the toner delivery means 362 via the air supply port 366. This promotes fluidization of the toner discharged from the toner delivery unit 362, and the toner transfer by the toner delivery unit 362 is more reliable. Also, air supply means 367
The supply of air to is performed through an air transfer pipe 371 connected to the air suction port 370. Here, the air transfer pipe 371 is connected to the developing device 200 as shown in FIGS.
Are connected via a joint 217 to the toner collecting device 209 of the printer. As a result, the outflow / inflow of air in the air supply means 367 is circulated with the developing device 200. The air supply means 367 is driven at substantially the same timing as the drive motor 358 of the toner delivery means 362.

The toner that has passed through the toner delivery means 362 is fed through a toner supply pipe 352 through an introduction hole 213a of a toner collection device 209 which is a part of the toner supply unit 200B of the development device 200 of the copying machine main body 100.
Sent inside. It is effective to use a material that is flexible and has excellent toner resistance (for example, soft vinyl chloride, nylon, Teflon, or the like) for the toner supply pipe 352. Also, as described above, the toner supply pipe 352
By using a flexible material, the transfer direction can be arbitrarily selected up, down, left and right.

Next, with reference to FIGS. 8, 9 and 10, an example of the configuration of the recovered toner transfer device 400 will be described. 8 and 9, the toner collected by the photoconductor cleaning unit 300 of the copying machine main body 100 is collected by a collected toner discharge unit 301 provided in a part of the photoconductor cleaning unit 300. Transfer device 4
00 is transported to the toner guide member 403 which is a part of the toner guide member 003. At this time, the toner is conveyed by the collected toner discharging unit 30.
This is performed by a collected toner discharging member 302 (a coil screw or the like) provided in the apparatus 1. The toner guide member 403 serves as a toner transfer path for sending toner from the photoconductor cleaning unit 300 to the toner sending unit 404.

Similarly, the toner collected by the cleaning device 251 of the transfer belt unit 250 is also transferred from a collected toner discharge unit 252 provided in a part of the transfer belt unit 250 to a collected toner transfer device engaged therewith. The sheet 400 is transferred to a toner guide member 403 which is a part of the sheet 400. At this time, the toner is conveyed by a collected toner discharging member 253 provided in the collected toner discharging section 252.
(Such as a coil screw).

8 and 9, reference numeral 101 denotes a main body structure (main body driving side plate) of the copying machine main body 100. The main body structure 101 includes a photoconductor cleaning unit 30.
0, a transfer belt unit 250, a photoreceptor 150, a developing device 200, other image forming members, a collected toner transfer device 400, and the like.

In this embodiment, the transfer belt unit 2
Although an example of a copying machine using 50 is shown, a conventional corona transfer device or bias roller transfer device may be used instead of the transfer belt unit 250.
Since these transfer devices usually do not have a cleaning device for the transfer device, the transfer belt cleaning device 251 in FIGS. 1 and 8 of the present embodiment is unnecessary.

Next, the toner delivery means 404 in the recovered toner transfer device 400 will be described. 8 to 10
As shown in FIG. 7, the toner delivery means 404 uses a screw pump which is commonly known as a powder pump and is generally called a mono pump. This is basically composed of a rotor 405 that moves toner in the axial direction by rotation, and a fixed stator 406 made of an elastic member such as a rubber material and surrounding the rotor 405. It is held by a holder 407. Also, the rotor 4
05 is substantially coaxially engaged with one end of the horizontal transport screw 408, and the other end of the horizontal transport screw 408 is supported by a bearing 410 fixed to a support member 420 through a seal member 409, and a driven gear outside the hopper is provided. 411, and the driven gear 411 is engaged with a drive motor 413 via a drive gear 412.

A hopper 414 in which the horizontal transport screw 408 is disposed is supported by a support member 420 and engages with the toner guide member 403. The hopper 414 receives toner from the collected toner discharge sections 301 and 252 of each cleaning means. The collected toner transferred via the member 403 is
A recovery toner transfer path for transferring the toner to the toner delivery unit 404 is configured.

Rotor 40 in toner delivery means 404
5. The size of the stator 406 and the number of rotations of the rotor 405 are selected according to the transfer distance and transfer amount of the toner. Further, the drive motor 413 determines the timing at which collected toner is generated, that is, the photoconductor 150 and the transfer belt unit 2.
It is driven at substantially the same timing as the drive of 50.

In this embodiment, the toner sending means 404 is used.
Is driven by a drive motor 413. If the drive motor 413 is connected to a drive system of the main body (a drive system such as a photoconductor and a cleaning device) via a drive member such as a gear, the drive motor 413 is driven. Can be omitted, which is advantageous for further downsizing, simplification, and cost reduction.

Next, the air supply means in the recovered toner transfer device 400 will be described. Toner sending means 40
In No. 4, there is a gap of about 1 mm between the outer side surface of the stator 405 and the inner side surface of the holder 407, which communicates with the toner passage. An air supply port 421 is provided so as to blow into the toner passage from the gap. The air supply port 421 communicates with an air discharge port 416 provided in an air supply means 415 including an air pump via an air transfer pipe 417. doing.

When activated, the air supply means 415 blows air at a rate of about 0.5 to 2.0 liters / minute into the toner passage of the toner delivery means 404 via the air supply port 421. This promotes fluidization of the toner discharged from the toner delivery unit 404, and the toner transfer by the toner delivery unit 404 is more reliable. Also, the air supply means 415
The supply of air to the air is performed via an air transfer pipe 419 connected to the air suction port 418. Here, the air transfer pipe 419 is connected to the developing device 200 as shown in FIGS.
Are connected via a joint 217 to the toner collecting device 209 of the printer. As a result, the outflow / inflow of the air in the air supply unit 415 circulates with the developing device 200. The air supply means 417 is driven at substantially the same timing as the drive motor 413 of the toner delivery means 404.

The collected toner that has passed through the toner sending means 404 is a collected toner transfer pipe 4 serving as a collected toner transfer means.
02, the toner is fed into the developing device 200 from the introduction hole 213b of the toner collecting device 209 which is a part of the toner replenishing portion 200B of the developing device 200 of the copying machine main body 100. still,
It is effective to use a material that is flexible and has excellent toner resistance (for example, soft vinyl chloride, nylon, Teflon, etc.) for the collected toner transfer pipe 402. In addition, by using a flexible material for the collected toner transfer pipe 402 as described above, the transfer direction can be arbitrarily selected from up, down, left, and right.

FIG. 11 is a block diagram showing an example of a control system of the toner supply device and the recovered toner transfer device in the image forming apparatus of the present invention. In FIG. 11, the CPU 7
10 is a known microprocessor, memory, clock,
A central processing unit including a counter, an I / O port, an interface, a control circuit, and the like.
0 and a toner supply device 350 and a collected toner transfer device 400 by a control device 700 having a driver 720.
Is controlled, supply of new toner to the developing device 200,
The collected toner is recycled.

The toner remaining amount in the toner transfer container 210 of the developing device 200 is determined by a toner near-end detector 218 (made of a piezoelectric sensor, as shown in FIG. 3).
0 is attached to one end surface of the control device 700 and the output is detected by the CPU 71 of the control device 700.
It is taken into 0. If the result of this detection output indicates that toner supply to the developing device 200 is necessary, the driver 720
, A drive motor 358 and an air supply unit 367 of the toner delivery unit 362 of the toner transfer device in the toner supply unit 350 are driven. By these controls, a constant amount of toner is always stored in the developing device 200, and a stable developing process is guaranteed. Also, even if toner is supplied by the toner supply device 350, if the toner near end detector 218 determines that the toner storage amount is out of toner, an operation panel (not shown) provided on the copying machine main body 100 is used. Is displayed on the display section, and the image forming operation is stopped as necessary. Thus, toner supply to the toner supply device 350 can be performed at an appropriate time.

During image formation, the collected toner is removed from each of the cleaning devices 300 and 251 by the developing device 20.
The apparatus is configured to drive the drive motor 413 and the air supply means 415 of the collected toner transfer device 400 to transfer the collected toner to zero. As a result, the collected toner can be reliably recycled.

The CPU 710 of the control device 700 has a timer function, and the drive motor 3 of the toner supply device 350 and the collected toner transfer device 400 is driven at an arbitrary timing.
58, 413, the air supply means 367, 415, etc., can be controlled.

[0050]

The toner transfer device used in the conventional image forming apparatus generally employs a toner transfer method using a coil screw or the like and a pipe. However, mechanical stress caused by the coil screw and the pipe causes damage to the toner. (Blocking, agglomeration, heat fusion, etc.), and the arrangement of the toner transfer path is considerably restricted due to the method of rotating the coil screw. On the other hand, in the image forming apparatus according to the first aspect, the toner transfer device includes a toner pump of a powder pump type (screw pump) and an air supply unit (air pump), and the inside of the toner transfer pipe is air. Since the toner is transferred in an air-fuel mixture state, little mechanical stress is applied, and since there is no rotating member such as a coil screw in the toner transfer pipe, a flexible pipe is used for the toner transfer pipe. Therefore, the arrangement of the toner transfer path can be freely performed like an electric wire arranged in the apparatus, and there is almost no restriction on the layout. The problem of the toner scattering at the toner discharge portion where the toner is transferred, which is a problem of the powder pump system (screw pump), is to connect the air suction portion of the air supply means to the space of the toner discharge portion and force the air. By sucking the air pressure, the air pressure can be reduced and prevented. In addition, the air suction is performed using an air supply means (air pump) for supplying the air required by the powder pump, so the optimum suction amount (= the air supply amount by the powder pump) is low and the cost is low. Can be realized.

In the image forming apparatus according to the second aspect,
The toner collecting device provided in the toner discharge section promotes separation of toner and air, and supplies air to the air supply means (air pump).
Because the amount of toner flowing into the path can be reduced,
The reliability of the present toner transfer device can be improved.

In the image forming apparatus according to the third aspect,
Since a filter is provided at the air suction part of the air supply means (air pump) connected to the toner discharge part, the toner and air are reliably separated by the filter, and only the air is sucked into the air suction part of the air supply means. So
The toner can be prevented from flowing into the path of the air supply means, and the reliability of the toner transfer device can be improved.

Therefore, according to the present invention, reliable toner transfer can be achieved with a simple and low-cost apparatus configuration, and the problem of toner scattering at the toner transfer destination (toner discharge section) can be solved. An image forming apparatus provided with a configuration for transferring toner (at least one system for supplying, collecting, and recycling toner) can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus showing one embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a configuration example of a developing device of the image forming apparatus illustrated in FIG.

FIG. 3 is a perspective view of a toner supply unit of the developing device shown in FIGS.

FIG. 4 is a front view of the toner supply unit shown in FIG.

FIG. 5 is a cross-sectional view of the toner supply unit shown in FIG.

6 is an exploded configuration diagram of a toner supply device of the image forming apparatus shown in FIG.

7 is a cross-sectional view of the toner supply device of the image forming apparatus shown in FIG.

FIG. 8 is a perspective view of a collected toner transfer device of the image forming apparatus shown in FIG.

FIG. 9 is a sectional view of a main part of a collected toner discharge unit and a collected toner transfer device of each cleaning device of the image forming apparatus shown in FIG.

FIG. 10 is a sectional view of a main part of the recovered toner transfer device shown in FIG.

FIG. 11 is a block diagram illustrating an example of a control system of a toner supply device and a collected toner transfer device in the image forming apparatus of the present invention.

[Explanation of symbols]

 100: Copier (image forming apparatus) main body 150: Photoconductor (image forming body) 200: Developing device 200A: Developing unit 200B: Toner replenishing unit 206: Agitator 208: Toner replenishing roller 209: Toner collecting device 210: Toner transfer Container 212: Hopper 213a: Inlet hole (connection portion of toner supply pipe) 213b: Inlet hole (connection portion of collected toner transfer pipe) 214: Toner discharge hole 215: Air discharge member 216: Filter 217: Joint 218: Toner near end Detector 250: Transfer belt unit 251: Transfer belt cleaning device 252: Collected toner discharge unit 300: Photoconductor cleaning unit 301: Collected toner discharge unit 350: Toner supply device 352: Toner supply pipe (toner transfer unit) 353: Toner storage Container 358 : Drive motor 360: agitator 361: horizontal transport screw 362: toner delivery means (screw pump) 363: rotor 364: stator 365: holder 367: air supply means 371: air transfer pipe (air suction unit) 400: recovered toner transfer device 402: Recovered toner transfer pipe (toner transfer means) 403: Toner guide member 404: Toner delivery means (screw pump) 405: Rotor 406: Stator 407: Holder 408: Horizontal transfer screw 413: Drive motor 414: Hopper 415: Air supply Means 419: Air transfer pipe (air suction unit) 700: Control device

Claims (3)

[Claims] An electrostatic latent image is formed on an image forming body, and the latent image is developed with a toner in a developer of a developing device into a visible image, and the visible image is transferred to a transfer material. In an image forming apparatus using an electrophotographic process for forming an image, a rotor that moves toner in the axial direction by rotating, and a rotor that is disposed so as to include the rotor and forms a passage of the rotor to make contact with the rotor A toner transfer device comprising: a toner delivery unit having a stationary stator to be engaged; and an air supply unit configured to supply and fluidize air to the toner moving in the toner delivery unit. A toner transfer unit that serves as a transfer path for the toner sent from the toner transfer device, wherein an air suction unit of an air supply unit in the toner transfer device is connected to a toner discharge unit of the toner transfer unit; An image forming apparatus having a configuration connected to a space, wherein the toner transfer according to the above configuration is used for at least one of supply, collection, and recycling of toner in an electrophotographic process. 2. An image forming apparatus according to claim 1, wherein only a toner is separated and collected from a mixture of the transferred toner and air at a connection destination (toner discharge portion) of said toner transfer means. The toner collecting means is formed in a conical shape, the upper surface thereof is connected to the toner transfer means, the upper surface thereof is connected to an air suction part of the air supply means, and the lowest part thereof is provided with a toner discharging means. An image forming apparatus having an outlet. 3. The image forming apparatus according to claim 1, wherein the air suction unit of the air supply unit is connected to a connection destination (toner discharge unit) of the toner transfer unit via a filter. Characteristic image forming apparatus.