JPH1184805A - Developing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To open the shutter of a developing container at the replenishing position of developer and to close it at a position other than the replenishing position of the developer. SOLUTION: This device is constituted so that plural developing units Dk, Dy, Dm and Dc successively stopped at a first stop position P1 where the latent images of respective color components formed on the surface of an image carrier 16 are developed to the toner images of respective colors are provided with the developing containers 61 having a developer replenishing port (73a) for replenishing the container with the new developer, a developer replenishment member (Th) replenishing the container with the new developer from the port (73a) by a carrying member for replenishing 77 carrying the new developer to the port (73a) and the replenishing port shutter 82 opening and closing the port (73a). Besides, it is composed of a shutter driving device opening the shutter 82 by mechanically interlocking with the action of the carrying member 77 at the developer replenishing position P1 and closing it when the developing unit is moved to the other position from the position P1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device for developing an electrostatic latent image formed on an image carrier into a toner image in an image forming apparatus such as an electrophotographic copying machine or a laser printer. And a developing device using a two-component developer composed of a carrier.

[0002]

2. Description of the Related Art Conventionally, in a dry copying machine or the like, a developing device using a two-component developer composed of a toner and a carrier has been used. In such a developing device, while the toner is consumed by the developing operation, the carrier is not consumed and remains in the developing device. Accordingly, the carrier agitated together with the toner in the developing device is deteriorated as the stirring time becomes longer, because the toner adheres to the surface of the carrier and becomes contaminated. For this reason, the charging performance of the developer gradually decreases, and image quality defects such as fogging occur, which causes deterioration in image quality.

In order to prevent image quality defects such as fogging, it is necessary to periodically replace the developer in the developing container. Further, maintenance for replacing the developer is troublesome. Therefore, for the purpose of non-replacement of the developer, an apparatus capable of suppressing the deterioration of the charging performance by replenishing the carrier and the toner into the developing container and discharging the deteriorated developer having the lowered charging performance from the developing container. Proposed. This type of technology is conventionally called a “trickle development system”, and the following technology (J01) is known.

(J01) (Technique described in Japanese Patent Application Laid-Open No. 61-117575) In the technique described in this publication, a shutter member is provided at a developer supply port formed in a developing container of a developing device that rotates. The shutter member is opened by its own weight or by a plunger mechanism at a developer replenishing position (an upper position or a lower position at which the developing device is rotated and stopped), and the shutter member is always kept at a position other than the developer replenishing position. Closed. This prevents the developer from flowing out of the developer supply port even if the developer supply port opens downward due to the rotational movement of the developing device.

[0005]

[Problems to be solved by the invention]

(Problem of (J01)) The prior art (J01) has the following problem. (A) When the shutter member opens and closes by its own weight,
When vibration or impact is applied to the developing container at a position other than the developer supply position and at a position where the developer supply port of the developing container opens downward, the shutter member is opened, and the developer in the container flows backward. In addition, when the developing container is detached from the developing device, if the developing container is tilted, the shutter member is easily opened, and there is a problem that the developer is spilled. (B) When the shutter member is opened and closed by the plunger mechanism, a power source for operating the shutter member must be provided as in the case of the plunger mechanism, which causes a problem that the production cost of the image forming apparatus increases. (C) Since the stop position for performing the developing operation is different from the stop position for replenishing the developer, the developer is replenished into the container when a large number of single color copies are performed and the developer in the developer container is consumed in a large amount. However, there is a problem that the toner density is reduced and the image quality is reduced.

In view of the above circumstances, the present invention provides a developing position in which a plurality of developing units having a developing container provided with a shutter member for opening and closing a developer supply port for replenishing a new developer into the container perform development. 90 °, 180 ° from the developing position,
A developing device for replenishing a developer in a developer container at a developer replenishing position set at any of the stop positions at 270 ° has the following contents (O01) to (O02). (O01) Open the shutter of the developer stopped at the stop position (developer supply position) for replenishing the developer, and move the developer to a position other than the stop position (developer supply position) for replenishing the developer. Close the shutter. (O02) To be able to supply the developer into the developing containers of the respective developing devices stopped at the stop position (developing position) where the developing operation is performed.

[0007]

Next, the present invention devised to solve the above-mentioned problems will be described. The elements of the present invention are used to facilitate correspondence with the elements of the embodiments described later. , The reference numerals of the elements of the embodiment are enclosed in parentheses. The reason why the present invention is described in correspondence with the reference numerals of the embodiments described below is to facilitate understanding of the present invention, and not to limit the scope of the present invention to the embodiments.

According to the present invention, in order to solve the above-mentioned problems, a developing device of the present invention has the following requirements. (A01) A plurality of image writing devices (ROS) corresponding to image information are provided. A rotating shaft (Do) which is arranged adjacent to the surface of the image carrier (16) on which a latent image of the color component is written and rotates and is rotatably supported by fixed frames (F1, F2). And a plurality of developing devices (Dk, Dy,
Dm, Dc) (H), (A02)
The plurality of developing devices (Dk, Dy, Dm, Dc) are developed into latent images of respective color components on the surface of the image carrier (16) into toner images of respective colors by the rotational movement and stop of the rotation shaft (Do). The developing device supporting member (H), and (A03) the new developer, which are sequentially stopped at each of the stop positions rotated by 90 °, 180 °, and 270 ° from the first stop position (P1). A developer container (61) having a developer supply port (73a) for replenishing toner and a developer discharge port (68) for discharging surplus developer and containing a two-component developer composed of toner and carrier; A developing roll (R0) that conveys the two-component developer to a developing area adjacent to the surface of the image carrier (16) when moved to the first stop position (P1)
A developer stirring / conveying member (R1 + R2) for supplying a developer to the developing roll (R0); and a replenishing conveying member (77) for conveying a new developer to the developer replenishing port (73a). From the developer supply port (73a) to the developing container (61)
Replenishing member (Th) for replenishing the new developer into the inside
A supply port shutter (82) for opening and closing the developer supply port (73a); and a discharge port for conveying the developer discharged from the developer discharge port (68) toward the developer collection container (V). Developer discharging member (Hb) having transport member (72)
And a plurality of developing units (Dk, Dy, D
m, Dc), (A05) of the developing device (Dk, Dy, Dm, Dc) stopped at a predetermined stop position set at the developer supply position (P1) for supplying the developer to the developing container (61). The replenishment transport member drive device (TD) for operating the replenishment transport member (77), (A06) the replenishment transport member (77)
The supply port shutter (82) in mechanical association with the operation of
And a shutter operating device (SD) for closing the supply port shutter (82) when the developing devices (Dk, Dy, Dm, Dc) move from the developer supply position (P1) to another position.

(Operation of the present invention) In the developing device of the present invention having the above-described features, the image writing device (ROS) is provided with a plurality of colors corresponding to image information on the surface of the rotating image carrier (16). Write the latent image of the component. A developing device support member (H) arranged adjacent to the image carrier (16) supports a plurality of developing devices (Dk, Dy, Dm, Dc). The rotation axis (Do) of the developing device support member (H) is fixed to the fixed frames (F1, F2).
It is rotatably supported by 2).

At the first stop position (P1), the developer agitating / conveying member (R) of each of the developing units (Dk, Dy, Dm, Dc).
1 + R2) is a two-component developer composed of a toner and a carrier housed in a developing container (61) and a developing roll (R0)
To supply. The developing roll (R0) is a developing unit (Dk, D
y, Dm, Dc) move to the first stop position (P1), the developing region (Q) adjacent to the surface of the image carrier (16).
In 2), a two-component developer including the toner and the carrier is transported. The toner conveyed to the developing area (Q2) by the developing roll (R0) is consumed by the developing operation. Due to the consumption of the toner, the toner in the developing container (61) decreases and the carrier deteriorates. The developing units (Dk, D
y, Dm, Dc) are 90 degrees from the first stop position (P1).
The rotation is sequentially stopped at °, 180 、 ２ and 270 、 and stopped at a predetermined stop position set at the developer supply position (P1). The replenishing transport member driving device (TD) is configured to stop the replenishing transport member (7) of the developing device (Dk, Dy, Dm, Dc) stopped at a predetermined stop position set at the developer replenishing position (P1).
Activate 7). The shutter operating device (SD) mechanically interlocks with the operation of the replenishing transfer member (77) to open the replenishing port shutter (82) and newly develops the developer into the developing container (61) from the developer replenishing port (73a). The drug is replenished.

When the developing devices (Dk, Dy, Dm, Dc) move from the developer supply position (P1) to another position,
The shutter operating device (SD) closes the supply port shutter (82). The surplus developer containing the deteriorated carrier is discharged from a developer discharge port (68), and the discharge conveying member (72) transfers the developer discharged from the developer discharge port (68) to a developer collection container (68). V).

Accordingly, when the developing container (61) is stopped at the developer replenishing position (P1), the replenishing port shutter (82) opens the developer replenishing port (73a) and the developing container (61) When the supply port shutter (82) closes the developer supply port (73a) when moving from the supply position (P1) to another stop position, the developer supply port (73a) moves to a position where the developer supply port (73a) opens downward. Even so, the developer supply port (73a) is closed by the supply port shutter (82) member. Therefore, the developer in the container does not flow out of the developer supply port (73a) and flow back into the developer supply member (Th). Since the shutter operating device (SD) opens the supply port shutter (82) in mechanical linkage with the operation of the supply member (77), the supply port can be provided without providing a power source for operating the shutter. The shutter (82) can be opened.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Embodiment 1 of the developing device of the present invention
(A07) The developer replenishment position (P1) set at the first stop position (P1). (Operation of First Embodiment) In the first embodiment of the developing device of the present invention, the developer supply position (P1) is set to the first stop position (P1). Therefore, the developing operation and the developer replenishing operation are performed at the first stop position (P1). Accordingly, when the developing device (Dk, Dy, Dm, Dc) stops at the first stop position (P1), the supply port shutter (82) of the developing device (Dk, Dy, Dm, Dc) causes the developer supply port ( Open 73a). Then, the developing device (D
When (k, Dy, Dm, Dc) moves from the first stop position (P1) to another stop position, the supply port shutter (82) closes the developer supply port (73a). Therefore, at the first stop position (P1) where the developing operation is performed, new developer can be replenished in the developing container (61). Since a large number of single color copies can be made,
Even when the developer 1) is consumed in a large amount, a decrease in the toner concentration in the container can be prevented.

(Embodiment 2) Embodiment 2 of the developing device according to the present invention is characterized by satisfying the following requirements in the present invention or Embodiment 1 described above. (A08) Development supply position ( P1), the developing devices (Dk, Dy, Dm, D) stopped
When c) moves from the developing replenishment position (P1) by the rotation of the developing device supporting member (H), the moving member engages with the operating member (Pi) supported by the fixed frames (F1, F2) and moves. A shutter operating device (SD) having a moving member (83) for closing and closing the supply port shutter (82) when engaged with the operating member (Pi) and moved.

(Effect of Second Embodiment) In the second embodiment of the developing device of the present invention, the closing moving member (83) of the shutter operating device (SD) is stopped at the developing replenishing position (P1). When (Dk, Dy, Dm, Dc) moves from the developing replenishment position (P1) by the rotation of the developing device supporting member (H), the operating member (Pi) supported by the fixed frames (F1, F2) is moved. Engage and move. The developing container (61) when moved by engaging with the operating member (Pi);
Closes the supply port shutter (82).

Therefore, the developer supply position (P1)
When the developing container (61) moves from the developer replenishing position (P1) to another stop position, the replenishing opening shutter (82) opened when the developing container (61) is stopped in the state described above. 73a) is closed. Therefore, when the closing moving member (83) engages with the operating member (Pi) and moves, the supply port shutter (82) of the developing container (61).
Is closed, the supply port shutter (82) of the developing container (61) can be closed at a position other than the developer supply position (P1) without providing a power source for operation.

(Embodiment 3) Embodiment 3 of the developing device of the present invention is characterized by having the following requirements in the present invention or any of Embodiments 1 and 2 of the present invention. (A09) The developing device (Dk, Dy, D
m, Dc) stops at the developer supply position (P1), the developer storage containers (111k, 111y, 111m,
111c), a developer carry-in port (76) into which the developer is carried in.
b) a developer supply cylinder (76) having a supply port connection part (76a) connected to the developer supply port (73a) at the other end and extending along the rotation axis (Do); A developer supply member (77) provided in the developer supply cylinder (76) for transporting the developer conveyed to one end of the developer supply cylinder (76) to the other end; Member (T
h).

(Operation of Third Embodiment) In the third embodiment of the developing device of the present invention, the developer storage container (111)
k, 111y, 111m, and 111c), the developing units (Dk, Dy, Dm, and Dc) send the developer to the developer supply position (P
When stopped at 1), the developer is supplied to the developer supply port (76b) at one end of the developer supply cylinder (76) of the developer supply member (Th). A replenishing developer transport member (77) provided in the developer replenishing cylinder (76) includes a developer replenishing cylinder (76).
The developer carried into one end is transported along the rotation axis (Do) to the supply port connection portion (76a) at the other end. The developer transported to the supply port connection portion (76a) is supplied into the developing container (61) from the developer supply port (73a).
That is, the developer storage containers (111k, 111y, 11y) are stopped at the developer supply position (P1).
1m, 111c) can be replenished into the developing container (61).

(Embodiment 4) Embodiment 4 of the developing device according to the present invention is characterized by satisfying the following requirements in Embodiment 3 of the present invention, wherein (A010) K (black),
The developer storage containers (111k, 111y, 111m, 111) for storing developers having toners of Y (yellow), M (magenta), and C (cyan) colors and carriers.
c), (A011) The developer carrying port (76b) extends outward from the outer end of the developing device (Dk, Dy, Dm, Dc) at predetermined intervals in the axial direction of the rotating shaft (Do). (A012) a replenishment developer receiving section (100) communicating with the developer carrying-in port (76b) of the developer replenishment cylinder (76); A replenishment developer receiving port (93a) connected to the developer receiving portion (100) has an outer peripheral surface 90 degrees around the rotation axis (Do).
° and the developing units (Dk, Dy, Dm,
Dc), the rotating cylindrical members (Bk, By, Bm, B) mounted on the rotating shaft (Do) at predetermined intervals in the axial direction thereof.
c), (A013) fixedly supported by the fixed frames (F1, F2) and the rotating cylindrical members (Bk, By, Bm,
Bc) and each of the developing units (Dk, Dy, D
m, Dc) sequentially stops at the developer replenishing position (P1), and the replenishment developer receiving ports (93a) of the rotary cylindrical members (Bk, By, Bm, Bc) are sequentially connected to the developer supply. A fixed cylindrical member (F1a) having a mouth (86e),
(A014) The replenishment developer receiving port (93a) which is disposed in the space between the outer peripheral surface of the rotary cylindrical member (Bk, By, Bm, Bc) and the inner peripheral surface of the fixed cylindrical member (F1a) ) Ring-shaped sealing member (8)
8), (A015) The developer storage container (111k, 111
y, 111m, 111c) K (black), Y (yellow),
The developer having toners of M (magenta) and C (cyan) and a carrier is supplied to the developer supply port (86e).
Developer transfer pipe (114k, 114y, 11)
4m, 114c) and transport screw (116).

(Effect of Embodiment 4) In Embodiment 4 of the developing apparatus of the present invention, the developer storage container (111k,
111y, 111m, and 111c) contain toners of K (black), Y (yellow), M (magenta), and C (cyan), and a developer having a carrier. The fixed cylindrical member (F1a) is fixed and supported by the fixed frames (F1, F2), and the developing units (Dk, Dy, Dm, D
It has a plurality of developer supply ports (86e) corresponding to c).
Developer conveying pipe (114k, 114y, 114m, 11
4c) and the conveying screw (116) are connected to the K of the developer storage container (111k, 111y, 111m, 111c).
(Black), Y (Yellow), M (Magenta), C (Cyan)
The developer is conveyed to the developer supply port (86e). The rotating shaft (Do) corresponding to each of the developing units (Dk, Dy, Dm, Dc)
The rotating cylindrical member (B
k, By, Bm, Bc) are arranged inside the fixed cylindrical member (F1a). The rotating cylindrical member (Bk, By, Bm,
A replenishment developer receiving port (93a) provided on the outer peripheral surface of Bc) at an interval of 90 ° around the axis of the rotation axis (Do),
When the developing units (Dk, Dy, Dm, Dc) are sequentially stopped at the developer supply position (P1), they are connected to the corresponding developer supply ports (86e).

The developer supply cylinder (76) extends outward from the outer ends of the developing devices (Dk, Dy, Dm, Dc), and the developer carrying port (76b) is connected to the rotating shaft (Do). Are arranged at predetermined intervals in the axial direction. The rotating cylindrical member (Bk, By,
A replenishment developer receiving portion (100) connected to the replenishment developer receiving port (93a) of Bm, Bc) communicates with the developer carrying-in port (76b) of the developer replenishing cylinder (76). Therefore, when the developing devices (Dk, Dy, Dm, Dc) rotate by 90 ° and sequentially move to the stop position (P1), each replenishment developer receiving of the rotating cylindrical member (Bk, By, Bm, Bc) is performed. The opening (93a) is connected to each of the developing units (Dk, D
(y, Dm, Dc) are sequentially connected to the developer supply ports (86e) respectively. At this time, the developer supply port (8) is connected by the developer transport pipes (114k, 114y, 114m, 114c) and the transport screw (116).
6e), the developer is supplied to the developer supply port (86).
e), through the replenishment developer receiving port (93a) and the replenishment developer receiving part (100), the developer replenishing cylinder (7)
6) The developer is conveyed to the developer carrying-in port (76b).

The rotating cylindrical member (Bk, By, Bm, Bc)
A ring-shaped seal member (88) arranged in a space between the outer peripheral surface of the fixed cylindrical member (F1a) and the inner peripheral surface of the fixed cylindrical member (F1a) blocks the space between the adjacent replenishment developer receiving ports (93a), and Then, the space between the adjacent developer supply ports (86e) is shut off. Therefore, adjacent developer supply ports (86e),
The developers of different colors between (86e) move and mix in the space between the outer peripheral surface of the rotating cylindrical member (Bk, By, Bm, Bc) and the inner peripheral surface of the fixed cylindrical member (F1a). Can be prevented.

[0023]

Next, examples (embodiments) of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. In order to facilitate understanding of the following description, arrows X, Y,
The orthogonal coordinate axes X axis, Y axis, and Z axis are defined in the Z direction, and the arrow X direction is forward, the arrow Y direction is left, and the arrow Z direction is upward. In this case, the direction opposite to the X direction (front) (−X direction) is backward, the direction opposite to the Y direction (left) (−Y direction) is right, and the direction Z (upward) is opposite (−Z direction). Is below. Also referred to as the front-rear direction or the X-axis direction including the front (X direction) and the rear (-X direction), and the left-right direction or the Y-axis direction including the left (Y direction) and the right (-Y direction). Good,
It is referred to as a vertical direction or a Z-axis direction including the upper part (Z direction) and the lower part (-Z direction). Furthermore, in the figure, those with "•" in "○" mean arrows pointing from the back of the paper to the front, and those with "x" in "○" are from the table on the paper. It shall mean an arrow pointing to the back.

(Embodiment) FIG. 1 is an explanatory view of an entire image forming apparatus provided with an embodiment of a developing device of the present invention. FIG. 2 is an enlarged explanatory view of a main part of FIG. 3 is a cross-sectional view of the developing container at the developing position of FIG. 2, FIG. 3A is a diagram showing a state in which a supply port shutter is closed in the developing container of the developing position of FIG. 2, and FIG. 3B is a developing device of FIG. FIG. 7 is a diagram illustrating a state in which a supply port shutter is opened in a developing container at a position. FIG. 4 is a diagram showing a state in which the developing device of the embodiment is mounted on a rotating developing device support member. FIG. 5 is a perspective view of the developing container of the embodiment. FIG. 6 is a perspective view of the shutter operating device.

In FIG. 1, an image forming apparatus U has a platen glass (transparent document table) A1 on its upper surface, a digital copying machine U1 as an image forming apparatus main body, and is detachably mounted on the platen glass A1. Automatic document feeder U2. The automatic document feeder U2 moves the document Gi (i = 1,2,2) stored in the document feed tray TRk.
..) Are sequentially taken out, conveyed to a copy position on the platen glass A1, and the copied document is discharged to a document discharge tray TRh. The automatic document feeder U2 has a document presence sensor S1 for detecting the presence or absence of a document on the document feed tray TRk, a document registration sensor S2 for detecting the passage of the conveyed document, and the like.

The main body U1 of the copying machine has a UI (user interface) arranged on the upper surface thereof, and an I (document reading device) sequentially arranged below the platen glass A1.
It has an IT (Image Input Terminal), an IPS (Image Processing System), and an IOT (Image Output Terminal) as an image recording operation unit. The UI (user interface) includes an input operation member (not shown) such as a copy start button, a copy setting number input key, and the like, by which a user of the image forming apparatus U inputs an operation command signal such as a copy start signal; A display unit (not shown) on which information on the current setting state of U is displayed.

An IIT as an original reading device disposed below the transparent platen glass A1 on the upper surface of the copying machine main body U1.
Is the OP located at the platen registration position (OPT position)
It has a T registration sensor (platen registration sensor) Sp and an exposure optical system 1 as an image reading device. The exposure optical system 1 has a lamp unit 2 mounted on a full-rate carriage.
And a first mirror 4. Also, the exposure optical system 1
Has a mirror unit 5 mounted on a half-rate carriage that moves at half the moving speed of the full-rate carriage, and the mirror unit 5 has a second mirror 6 and a third mirror 7. . The exposure optical system 1 has a lens 8.

Then, the lamp unit 2 moves in the horizontal direction in FIG. 1 in parallel with the document, and the moving mirror unit 5 moves at a speed half the moving speed of the lamp unit 2 and a distance of 1/2. , The distance between the document Gi and the lens 8 is kept constant, and during that time, the reflected light of the document Gi illuminated by the lamp 3 passes through the exposure optical system 1 and passes through a CCD (solid-state imaging device). Element). The CCD converts the original reflected light converged on the imaging surface into R (Red, G), G (Green,
(Green) and B (Blue, blue) are converted into electric signals of three color components.

The IPS (image processing system) has read image data output means 11 for reading the three color electric signals obtained by the CCD and write image data output means 12 for outputting write image data. I have.
The read image data output unit 11 is a conventional AGC
(Auto gain controller), AOC (auto offset controller), ADC (analog-to-digital converter), and the like. The write image data output means 12 to which the image data output from the read image data output means 11 is input is the input R, G, B3
After performing shading correction on the color image data, Y
(Yellow), M (magenta), C (cyan), K
It has a function of converting the image data into image data of four colors (black) and performing conventionally known image processing such as enlargement / reduction correction, density correction, and the like on the image data, and temporarily stores the image data. It has an image storage memory 13 for storing data. The write image data output means 12 outputs the processed image data to the IOT laser drive signal output device 14 as write data. The IOT laser drive signal output device 14 includes:
The laser drive signal corresponding to the input image data is ROS
(Optical writing scanning device, that is, a latent image writing device, an image writing device).

The ROS scans an electrostatic latent image writing position Q1 on the rotating image carrier 16 with a laser beam L modulated by the input laser drive signal. A charger 17 for uniformly charging the image carrier 16 is disposed along the rotating image carrier 16 and upstream of the latent image writing position Q1 in the moving direction of the image carrier 16. After the image carrier 16 is uniformly charged by the charger 17,
At the latent image writing position Q1, an electrostatic latent image is written by the laser beam L.

A rotary developing unit (developing unit) for developing the electrostatic latent image into a toner image is provided in a developing area Q2 on the downstream side of the latent image writing position Q1 along the moving direction of the image carrier 16. (Device) D is disposed. The developing unit D
Has developing units Dk, Dy, Dm, and Dc mounted around the rotation axis Do for developing the four colors, respectively.
k, Dy, Dm, and Dc are developing units that perform development using a two-component developer having toners and carriers of respective colors of K, Y, M, and C. Developing units Dk, Dy, Dm, Dc for each of the four colors
The first stop position (development position, that is, the development area Q) shown in FIG.
2) It is configured to stop at P1, the second stop position P2, the third stop position P3, and the fourth stop position P4.

In FIG. 1, the rotating image carrier 16 is rotated.
A toner image density sensor SNd is arranged on the downstream side of the developing area Q2 along the surface of the image forming apparatus, and a transfer drum 21 and a transfer unit 22 are arranged at a transfer position Q3 set on the downstream side. Further, along the rotating image carrier 16,
A static eliminator 23 and a cleaner unit 24 are arranged downstream of the transfer position Q3. The toner image density sensor SNd is composed of a light emitting element and a light receiving element disposed in the vicinity of the image carrier 16, and is a toner image (patch) formed by developing a test electrostatic latent image formed on the image carrier 16. ) Is measured to detect the toner image density.
The transfer device 22 extends along the rotation direction of the transfer drum 21.
On the downstream side, a static eliminator 26, a cleaner 27, and an adsorption corotron 28 are sequentially arranged. The adsorption corotron 28 is disposed at the adsorption position Q4.

Below the transfer drum 21, a first paper feed tray T for storing recording sheets is sequentially arranged downward.
1, a second paper supply tray T2, an intermediate tray T0 for temporary stock used for duplex copying, a third paper supply tray T3, a fourth paper supply tray T4, a fifth paper supply tray T5 for storing a large number of recording sheets. Is detachably stored. The intermediate tray T0 is an intermediate tray used when circulating the recording sheet (hereinafter referred to as a sheet) S on which the first copy has been performed at the time of double-sided copying and retransmitting the recording sheet S to the transfer position Q3. A manual feed tray 31 is provided at an upper right position of the first paper feed tray T1. The recording sheets conveyed from the manual feed tray 31 by the paper feeding rollers R6 and R7 and the recording sheets sent out from the paper feeding trays T1 to T5 pass through the first sheet conveying path 32 to the suction position Q4. It is designed to be transported. The recording sheet conveyed in the first sheet conveyance path 32 is detected by the registration sensor SNy, temporarily stopped by the registration roller 33, and then conveyed to the suction position Q4 at a predetermined timing. At the suction position Q4, the sheet S
Is adsorbed to the transfer drum 21 by an adsorption roll 34.

The sheet S adsorbed on the transfer drum 21
Is transferred to the transfer position Q3 as the transfer drum 21 rotates. The transfer unit 22 transfers the toner image on the image carrier 16 to the sheet S passing through the transfer position Q3.
After the developer remaining on the surface of the image carrier 16 that has passed the transfer position Q3 is recovered by the cleaner unit 24, the image carrier 16 is uniformly charged again by the charger 17. At the suction position Q4, the transfer drum 21
The sheet S adsorbed to is rotated four times in the case of full color,
Every time it passes through the transfer unit 22, K (black), Y (yellow),
Magenta (M) and C (cyan) toner images are transferred. The sheet S on which the four full-color images are formed is separated from the transfer drum 21 by the separation corotron 36,
The sheet is conveyed to the fixing position Q5 through the second sheet conveying path 37.

At the fixing position Q5, a pair of fixing rolls 41 and 4 composed of a heating roll 41 and a pressure roll 42 are provided.
The fixing device F having a fixing position Q5
Is configured to fix the unfixed toner image on the sheet S passing through the sheet S by heating and pressing. The heating roll 41
A fixing heater 41h is built therein. A discharge roller 43 for discharging sheets to a sheet discharge tray TR is provided in the second sheet transport path 37 downstream of the fixing position Q5.

In the second sheet conveying path 37, a switching gate 44 is disposed upstream of the discharge roller 43.
The switching gate 44 is used when switching the transport direction of the sheet S on the second sheet transport path 37 to the sheet circulation path 46 or the direction of the sheet discharge tray TR. The sheet circulation path 46 is connected to a sheet reversing path 47 and the intermediate tray T0 via a switching gate 48. The switching gate 48 is configured to direct the sheet S of the sheet circulation path 46 to the sheet reversing path 47 when performing double-sided copying. The sheet-shaped and comb-shaped mylar gate 49 provided in the sheet reversing path 47 allows the sheet S to move downward by elastic deformation when the passing sheet S is conveyed downward. When the sheet S that has passed through the switch 49 is switched back and conveyed upward, the sheet S is guided in the direction of the intermediate tray T0. Sheet S once stored in intermediate tray T0
Is transported again from the intermediate tray T0 to the suction position Q4 by the first sheet transport path 32.

2 and 4, the developing unit D
The rotary shaft Do on which the developing devices Dk, Dy, Dm, and Dc of four colors K, Y, M, and C are mounted is a front wall portion and a rear fixed portion of a fixed cylindrical member F1a fixedly supported on a front fixed frame F1. It is rotatably supported by a frame F2 (see FIG. 4). A driven gear G1 meshing with the driving gear G0 is fixed to the rear (-X direction) outer end of the rotation shaft Do. The drive gear G0 is driven to rotate by a drive motor (not shown). When the gear G0 rotates, the gear G1 and the rotation shaft Do are also driven to rotate integrally.

In FIG. 4, a front rotating plate 56 is fixedly supported at the front end of the rotating shaft Do, and a rear rotating plate 57 is fixedly supported at the rear end. It is supported so as to be able to rotate integrally with the shaft Do. The rotating shaft Do is provided with a plastic connecting block 58 for covering the outer periphery of the rotating shaft Do at an adjacent portion on the rear surface side of the front rotating plate 56 and an adjacent portion on the front surface side of the rear rotating plate 57. ing. The connecting block 58 is connected to the developing units Dk, Dy,
Dm and Dc are used to connect and support. The connection block 58 has a substantially square cross section (see FIG. 2) and has four side surfaces extending in the axial direction. A pair of front and rear pin insertion holes 59 and 5 are provided on each side surface.
9 are formed. The pin insertion holes 59, 59 are holes into which projecting pins of developing units Dk, Dy, Dm, Dc described later are inserted, and are holes used for positioning and fixing the developing units. The developing device support member H is constituted by the symbols Do and 56 to 59.

In FIG. 2, each of the developing devices Dk, Dy, Dm,
Dc rotates with the rotation of the rotation shaft Do due to the rotation of the drive gear G0, and sequentially moves to the first stop position (development position,
(The developer supply position, the developer discharge position) P1, the second stop position P2, the third stop position P3, and the fourth stop position P4. In the present embodiment, the first stop position P1 is a developing position, and at the same time, serves as a developer replenishing position and a developer discharging position. At the first stopping position, the developing devices Dk, Dy, Dm, and Dc are stopped. A developing operation is performed. Each of the developing units Dk, Dy, Dm, and Dc is a developing container 61, respectively.
In the first stop position, new developer is supplied into each developing container 61 by the developer replenishing member (Th), surplus developer is discharged from the developing container 61, and surplus development is discharged. The transfer of the agent (described later) is performed.

Each developing container 61 has a pair of front and rear projecting pins 62, 62 (see FIG. 3) on the outer surface thereof. The pair of projecting pins 62, 62 are inserted into pin insertion holes 59, 59 of the developing device support member H, and
1 is used for positioning and fixing. Since the developing units Dk, Dy, Dm, and Dc have the same configuration, the developing unit Dy will be described below. FIG. 2, FIG.
The developing container 61 of the developing device Dy contains a two-component developer composed of a negatively charged toner and a positively charged magnetic carrier. The developing container 61
Is a developing roll accommodating portion 63 that accommodates the developing roll R0,
It has a first developer reservoir 64 adjacent to the developing roll housing 63 and a second developer reservoir 65 adjacent to the first developer reservoir 64. A layer thickness regulating member 66 for regulating the layer thickness of the developer on the developing roll R0 is disposed in the developing roll accommodating section 63.
Further, a first stirring and conveying member R1 is disposed in the first developer reservoir 64, and a second conveying member R2 is disposed in the second developer reservoir 65.

As shown in FIGS. 2 and 3, a partition wall 67 is provided between the first developer reservoir 64 and the second developer reservoir 65 at portions other than both ends thereof. The first developer reservoir 64 and the second developer reservoir 65 are connected at connecting portions (not shown) at both ends in the front-rear direction (X-axis direction). The developing roll R0 shown in FIGS. 2 and 3 is a conventionally known one in which a sleeve is provided outside a magnet roll. And the first developer reservoir 6
The developer of No. 4 is attracted onto the surface of the developing roll R0 by the magnetic force of the magnet roll, and is conveyed. The shaft of the developing roll R0 is rotatably supported by the front rotation plate 56 and the rear rotation plate 57.

Gears G6 and G7 are mounted at the rear end of the rotation shaft of the first stirring and conveying member R1. A gear G8 is attached to the rear end of the rotation shaft of the developing roll R0.
Meshes with a second gear (not shown). The first and second stirring and conveying members R1 and R2 constitute a developer stirring and conveying member (R1 + R2).

When a rotational force is transmitted to the gear G6 (the transmission mechanism will be described later), the gears G7 and G8 and the gear of the second stirring and conveying member R2 rotate, and the developing roll R0 and the developer stirring and conveying member ( R1 + R2) rotates. Due to the rotation of the developer stirring and transporting member (R1 + R2), the developer in the first and second developer reservoirs 64 and 65 circulates while being transported in opposite directions. The second developer reservoir 6
On the side wall of the developing container 61 on the fifth side, a developer outlet 68 is formed. The developer outlet port 68 is provided with a discharge tube connecting portion 69 which bulges outward from the outer surface of the developing container 61. A developer discharge tube 71 is connected to the discharge tube connection portion 69, and the developer discharged from the developer discharge port 68 is discharged into the developer discharge tube 71 via the discharge tube connection portion 69. ing. A collection container communication portion 71a (see FIG. 5) is formed at the front end (X direction end) of the developer discharge cylinder 71. As shown in FIGS. 3, 4, and 5, a discharge conveying member 72 is rotatably disposed in the developer discharge tube 71. The discharge conveying member 72 includes a rotating shaft 72a and conveying blades 72b fixed to the outer peripheral surface of the rotating shaft 72a. A gear G9 (see FIG. 4) is fixed to the rear end (the end in the -X direction) of the rotating shaft 72a of the discharge conveying member 72. The gear G9 meshes with a gear (not shown) of the second stirring and conveying member R2. The developer discharging cylinder 71 and the discharging conveying member 72 constitute a developer discharging member Hb.

By the rotation of the discharge conveying member 72, the surplus developer in the developer discharging cylinder 71 is conveyed forward (in the X direction) and discharged from the collection container communicating portion 71a. ing. As shown in FIGS. 2 to 5, a developer supply port 73 a is formed in the upper lid 73 above (in the Z direction) the second developer reservoir 65. In order to prevent the new developer supplied from the developer supply port 73a from being discharged from the developer discharge port 68 immediately after the supply, the developer supply port 73a is connected to the developer discharge port 6a.
It is formed downstream of the position 8 in the transport direction.

In FIGS. 2, 3 and 6, on the outer peripheral side of the developer supply port 73a and on the upper surface of the upper lid 73, a developing roll accommodating portion 63 on the left side (Y direction) of the developing container 61 is provided.
The left communication member fixing wall 73L, which is the side surface, the right communication member fixing wall 73r formed lower than the left communication member fixing wall 73L, the front communication member fixing wall and the rear communication member fixing wall (not shown) are respectively upward. Are formed integrally so as to extend. Spring engaging portions 73d, 73d
Are formed. As shown in FIG. 3, a shutter engaging member 74 is disposed on the upper surface of the upper lid 73 on the outer surface side of the right communication member fixing wall 73r. The shutter engagement member 74 is a substantially L-shaped member, and an engagement portion 74a extending upward in contact with the outer surface of the right communication member fixing wall 73r.
And a shutter slide surface 74b which is inclined so as to climb rightward (-Y direction) from the engagement portion 74a.

Outside the upper lid 73 of the developing container 61 moved to the first stop position P1, above the fixed walls 73L, 73r, a supply port connecting portion 76a is provided at a position corresponding to the developer supply port 73a. Developer supply cylinder 76 is disposed. In the developer supply cylinder 76, a supply member 77 for supply is rotatably arranged as shown in FIG. The supply member 77 for replenishment includes a rotating shaft 77a and the rotating shaft 77a.
And a transport blade 77b fixed to the outer peripheral surface of the transport blade 77b. Also, as shown in FIG. 3 and FIG.
The closing member engaging pin Hp, whose tip is cut off obliquely, is fixed perpendicularly to the rotating shaft 77a, so that when the rotating shaft 77a rotates, the closing member engaging pin Hp rotates around the axis. Has become. Then, the proximity switch Sk disposed on the outer surface of the developing roll accommodating portion 63 of the developing container 61 on the side of the developer replenishing cylinder 76 detects the passage of the rotating closing member engaging pin Hp and rotates. The closing member engaging pin Hp is stopped at a predetermined position. The developer supply cylinder Th and the supply member 77 constitute a developer supply member Th (see FIG. 5).

The replenishing transport member 77 extends forward from an opening (developer carrying port) 76b at the front end (the end in the X-axis direction) of the developer replenishing cylinder 76. A bearing 78 (see FIG. 13) is rotatably supported at the front end (the end in the X direction) of the rotating shaft 77a.
By the rotation of the supply member 77 for replenishment, the developer carried into the developer replenishing cylinder 76 from the developer carry-in port 76b is conveyed rearward (in the −X-axis direction), and the replenishment port connection portion 76a And the second developer reservoir 65 (see FIG. 2) from the developer supply port 73a (see FIGS. 2, 3, and 5).
Is to be replenished inside.

2 to 6, the developer supply cylinder 7
6, a substantially rectangular parallelepiped communication member 79 is disposed between the supply port connection portion 76a and the developer supply port 73a. The direction matches the front-back direction (X-axis direction) of the developing container 61. The communication member 79 is fitted and fixed inside each of the communication member fixing walls above the developer supply port 73a.

In FIG. 6, the communication member 79 has a left wall 79L and a right wall 79r, which are both side surfaces on the long side, and a front wall 79f and a rear wall 79u, which are both short side surfaces which face the front-back direction. A communication passage 79a is formed inside the communication member 79. The upper end surface of the communication member 79 is formed with a curve so as to easily support the cylindrical outer surface of the developer supply cylinder 76. Left wall 79L and right wall 79r of communication member 79
Are formed with slits 79b for shutter guide. Plate-like guide members 81, 81 are fixed to the front wall 79f and the rear wall 79u of the communication member 79.
As shown in FIG. 5, each guide member 81 is
The shutter engaging member 7 disposed on the upper surface of the upper lid 73
It is configured to extend to the four sides (that is, the right wall 79r side). The position of the lower surface of each of the guide members 81 matches the position of the upper edge surface of the shutter guide slit 79b.

In FIG. 6, a rectangular supply port shutter 82 is guided by the shutter guide slits 79b, 79b in the short side direction (left-right direction) of the communication member 79 to open or close the communication passage 79a. It is supposed to. The left wall 79L of the supply port shutter 82
A tapered surface 82a is formed on the side (developing roll accommodating portion 63 side). It is easy to enter the slits 79b, 79b. The right wall 79 of the supply port shutter 82
The r (shutter engaging member 74 side) side is supported by a closing moving member 83 having the supply port shutter portion 82 and a shutter joint portion 83a integrally formed. Guided portions 83b, 83b extending leftward (Y direction) along front and rear walls 79f and 79u, which are both short side surfaces of the communication member 79, at both front and rear ends of a shutter joining portion 83a of the shutter support portion 83. Are formed.

The left end of the guided portion 83b on the front wall 79f side is bent in the forward direction of the communication member 79, and a front spring locking portion 83c is formed at the distal end thereof. The left end side of the guided portion 83b on the rear wall 79u side has a shaft portion 83d extending rearward (-X direction) of the communication member 79, and the shaft portion 83d
A rear spring locking portion 83e is formed at a position adjacent to the guided portion 83b on the rear wall 79u side. 4 and 6, the rear end of the shaft portion 83d of the closing moving member 83 passes between the gears on the rear side of the developing container 61, passes through the rear rotating plate 57, and Extend to the rear frame F2 when mounted on the developing device support member H, and extend to the right (-Y) on the front surface of the rear frame F2.
Direction). If it is impossible to pass between the gears behind the developing container 61 due to the position of the shaft portion 83d, the gears can be rearranged so as to pass between the gears. Also, the shaft 83d
The supply port shutter 82 and the closing moving member 83 of the shaft 83d penetrate the rear rotating plate 57 movably to the closing position and the opening position. The front end side of the portion bent rightward (-Y direction) has a pin engaged surface (see FIG. 6) 83f cut obliquely downward from above.
have.

As shown in FIGS. 4 and 9A, the pin engaged surface 83f is connected to the developing container 6 stopped at the first stop position P1.
The first supply port shutter 82 opens the communication passage 79a and the front side of the rear fixed frame F2 (the developing container 61).
Is engaged with an operating pin (operating member) Pi fixed to the surface on the side where is disposed. 83a
To the closing moving member 8
3 are configured.

2, 3, and 6, tension springs 84, 84 are locked to the front spring locking portion 83c and the rear spring locking portion 83d of the closing moving member 83, respectively. . The other ends of the tension springs 84, 84 are engaged with spring engaging portions 73d, 73d of the developing container 61, respectively.
The tension springs 84, 84 are connected to the closing moving member 83.
Further, the supply port shutter 82 supported by the closing moving member 83 is urged to the left (Y direction), and the supply port shutter 82 is pulled in a direction to close the communication passage 79 a of the communication member 79. ing. In addition, the said code | symbol 79-8
The shutter actuating device SD is constituted by the components indicated by 4, Hp and Pi.

In FIG. 4, a gear G11 is fixed to the rear end (the end in the −X-axis direction) of the rotation shaft 77a of the supply member 77 for supply in the developer supply cylinder 76. The gear G11 meshes with a gear G7 of the first stirring and conveying member R1 and a gear (not shown) of the second stirring and conveying member R2.
In FIG. 4, a driven gear G13 meshing with a drive gear G12 rotated and driven by a drive device (not shown) is supported by the rear fixed frame F2. The driven gear G13
And a gear G14 coaxial with the gear G6. The gear G6 is a gear that is coaxial with the gear G7 that rotates integrally with the first stirring and conveying member R1. As can be seen from FIGS. 4 and 5, the gear G14 supported by the rear fixed frame F2 is provided.
Is arranged so as to mesh with the gear G6 supported by each of the developing devices Dk, Dy, Dm, and Dc that has moved to the developing position P1 (see FIG. 2).

When the drive gear G12 is driven to rotate while the gears G14 and G6 are in mesh with each other, the rotational force is transmitted to the gear G7 via the gears G13, G14 and G6. The rotation of the gear G7 causes the first stirring and conveying member R1 to rotate. The rotation of the gear G7 is transmitted to the gear G8, the gear G9, the gear G11, the gear of the second stirring and conveying member R2, and the developing roll R0, the second stirring and conveying member R2, and the conveying member for discharging the developer discharge cylinder 71. 72, the supply conveying member 77 in the developer supply cylinder 76 rotates. The gears G12 to G14, G6,
G7, G9, G10, the drive motor for the gear G12 and the like constitute a discharge conveying member driving device JD (see FIG. 4).

FIG. 10 is a sectional view taken along line XX of FIG. FIG. 11 is a sectional view taken along line XI-XI of FIG. FIG.
2 is an explanatory diagram of a developer replenishing device of the developing device, which is a cross-sectional view taken along line XII-XII in FIG. FIG. 13 shows X in FIG.
FIG. 3 is a sectional view taken along line III-XIII. FIG. 14 is an explanatory diagram showing the positional relationship between the developer supply case and the developer supply device. FIG.
5 is a view as seen from the direction of the arrow XV in FIG. FIG.
At the front side (X side) of the front fixed frame F1, which is the front side (X direction) of the developer supply cylinder 76,
The fixed cylindrical member F1a is fixed. In FIGS. 4, 12, and 13, the fixed cylindrical member F1a is configured by connecting a plurality of ring-shaped members sealed in such a manner that toner of each color supplied to the developing container 61 does not mix colors in the front-rear direction. . That is, the fixed cylindrical member F1a is connected to the frame fixing ring-shaped connecting member Lb connected to the front surface of the front fixed frame F1; (Black) ring-shaped connecting members Lk, Y for replenishing the developer
(Yellow) ring-shaped connecting members Ly, M (magenta)
And a ring connecting member Lc for C (cyan) and a ring connecting member Lf for the front wall. Since the respective Lk, Ly, Lm, and Lc have the same configuration, only the K ring-shaped connecting member Lk will be described as a representative.

11 to 13, the ring-shaped connecting member Lk for K has a ring-shaped connecting member main body 86. In FIG. 11, other ring-shaped connecting members Lb, Lh, Ly, Lm, L
Three connection fixing portions 86a, 86b, 86c are formed to be connected to the front fixing frame F1 by screws N1a, N1b, and N1c. At a position deviated from the diameter of the outer peripheral surface of the ring-shaped connecting member main body 86, the developer supply portion 86d
6, the developer supply unit 86
A developer supply port 86e is formed inside d. A sponge cylindrical transport pipe receiving member 87 (see FIG. 11) is adhered to the open end surface (upper end surface) of the developer supply port 86e. The inner peripheral surface of the ring-shaped connecting member main body 86 has seal member fitting portions 86f, 86f on both ends.
(See FIG. 12).

In FIGS. 12 and 13, a ring-shaped seal member 88 having elasticity is attached to the seal member fitting portions 86f, 86f. The ring-shaped connecting member Lk for K is composed of a ring-shaped connecting member main body 86 and a pair of seal members 88, 88 elastically mounted on the inner peripheral surface of the ring-shaped connecting member main body 86. The Y-, M-, and C-ring connecting members Ly, Lm, and Lc have the same configuration as the K-ring connecting member Kk.
Each of the ring-shaped connecting members 87 is attached to the ring-shaped connecting member L.
When connected to b, Lh, Ly, Lm, and Lc and fixed to the front fixed frame F1, the outer surfaces of the seal member 88 are opposed to each other. Each sealing member 8
8, a ring-shaped spacer 89 (see FIGS. 12 and 13) is arranged.

The discharge ring-shaped connecting member Lh shown in FIG. 10 has a ring-shaped connecting member main body 86 'similar to the ring-shaped connecting member main body 86. Instead of the developer supply section 86d and the developer supply port 86e of the K ring-shaped connection member main body 86, a collection container connection port 86g 'is provided on the ring-shaped connection member main body 86' below the rotation axis Do. Formed on the side. The discharge ring-shaped connecting member Lh
Ring-shaped connecting member main body 86 '(see FIGS. 10 and 11)
Other configurations of the ring-shaped connecting member main body 86 for K
It is configured similarly to. The discharge ring-shaped connecting member Lh is composed of the ring-shaped connecting member main body 86 'and a seal member 88 mounted on the inner peripheral surface thereof (see FIGS. 12 and 13).
It consists of. A developer collecting container V is disposed below the collecting container connection port 86g '.

The frame fixing ring-shaped connecting member Lb
12 and 13 are joined to the rear side surface (-X side surface) of the discharge ring-shaped connecting member Lh, and have a ring-shaped connecting member main body 86 ". The connecting member main body 86 "has substantially the same shape as the ring-shaped connecting member main body 86 ', and the three connecting fixing portions 86a,
It has the same connection fixing part as 86b and 86c. Also,
The ring-shaped connecting member main body 86 ″ has a shorter overall axial length than the ring-shaped connecting member main body 86 ′,
The collection container connection port 8 is formed to about 1/2.
6g 'is omitted. The frame fixing ring-shaped connecting member Lb is fixed to the front fixing frame in a joined state.

In FIGS. 12 and 13, the ring connecting member Lf for the front wall is joined to the front side of the ring connecting member Lc for C (cyan), and the ring connecting member Lb for frame fixing. Ring-shaped connecting member main body 86 ″
And a flat portion Lf2 on the front end face of the cylindrical portion Lf1. The cylindrical portion Lf1 and the flat plate portion Lf2 are integrally formed. On the outer surface of the cylindrical portion Lf1, there are provided connection fixing portions similar to the three connection fixing portions 86a, 86b, 86c.

The ring-shaped connecting members Lb, Lh, Lk, Ly, Lm, Lc and Lf shown in FIGS.
Three connection fixing parts 86a, 86b, 86c of Ly, Lm, Lc
(See FIGS. 10 and 11) and the same L as those described above.
b, Lh, and Lf are fixed by screws N1a, N1b, and N1c.
By this, it is fixed to the front fixed frame F1. Also,
The front wall ring-shaped connecting member Lf rotatably supports the rotation axis D0 at the center of the flat plate portion Lf2. Each of the ring-shaped connecting members Lb, Lh, Lk, Ly, Lm, Lc,
Lf constitutes the fixed cylindrical member F1a.

In FIG. 4, FIG. 12, and FIG. 13, a plurality of rotating cylindrical members Bh, Bk,
A rotating cylindrical member B composed of By, Bm, Bc, and Bf is arranged. The rotating cylindrical member B has a central portion supported by being fitted to the rotating shaft D0, and is configured to rotate integrally with the rotating shaft D0. The rotating cylindrical member B is provided along the rotation axis D0 with the front rotation frame 5.
In the order from 6 forward, a discharge cylindrical member Bh that supports the tip of each developer discharge cylinder 71, and a K (black) cylinder that supports the tip of the developer supply cylinder 76 of the developer container 61 for each toner color. A member Bk, a cylindrical member By for Y (yellow) By, a cylindrical member Bm for M (magenta), a cylindrical member Bc for C (cyan), and a front cylindrical member Bf are connected to each other.

Since the cylindrical members Bk, By, Bm, and Bc have the same configuration, the K cylindrical member Bk will be described as a representative. In FIGS. 11 to 13, the K cylindrical member Bk
Has a cylindrical member main body 90. Cylindrical member body 90
Has the outer cylinder portion 91, the outer cylinder portion 91 has a rear-side large-diameter outer cylinder portion 92, and a front-side small-diameter outer cylinder portion 93 extending forward of the rear-side large-diameter outer cylinder portion 92. I have. The front small-diameter outer cylindrical portion 9
3 has the same outer diameter as the inner diameter of the rear large-diameter outer cylindrical portion 92, and as shown in FIG. 12, the K cylindrical member Bk is connected to other cylindrical members back and forth. At this time, the front small-diameter outer cylinder portion 93 is fitted into the rear large-diameter outer cylinder portion 92. In FIG. 11, a supply developer receiving port 93a is formed on the side surface of the front small-diameter outer cylindrical portion 93, and the positions shown in FIG. Thus, an inner bent portion 93b whose tip extends in the center direction and is bent, and an outer bent portion 93c whose tip extends and bends outward are formed.

In FIG. 11 to FIG.
0 has an inner cylinder portion 94 at the center thereof, and the inner cylinder portion 94 has a cylindrical front-side large-diameter inner cylinder portion 96 and a rear-side small-diameter inner cylinder portion 97. The outer diameter of the rear-side small-diameter inner cylinder portion 97 is formed to be the same size as the inner diameter of the front-side large-diameter inner cylinder portion 96,
As shown in FIGS. 12 and 13, when the K cylindrical member Bk is connected to other cylindrical members Bh and By before and after, the rear small-diameter inner cylindrical portion 97 is connected to the front large-diameter internal cylindrical portion 96. Is fitted within. At this time, the end surfaces of the inner cylindrical portions 94 come into contact with each other, and positioning in the front-rear direction is performed. Also, the cylindrical member main body 90
Has a ring-shaped connecting wall 98 for connecting the outer tubular portion 91 and the inner tubular portion 94 and four ribs 99 for reinforcing the strength. The outer peripheral edge of the connection wall 98 is connected to the boundary between the large-diameter outer cylindrical portion 92 and the front-side small-diameter outer cylindrical portion 93. The rib 99 is provided on the front side surface (X side surface) of the connection wall 98.
In total, four are formed every 90 °.

The inner cylindrical portion 94 has a rotary shaft fitting hole 94a formed in a rear portion thereof and a small diameter inner cylindrical portion fitting hole 94b formed in a front portion thereof. As shown in FIGS. 12 and 13, the rotating shaft fitting hole 94a is fitted to and fitted to the rotating shaft Do. Is fitted. The inner cylinder portion 94 has four fixing screw through holes 94c formed along the central axis. The connecting wall 98 includes the four ribs 9.
A supply member through hole 98a is formed in each wall portion divided into four by 9 and a bearing through hole (see FIG. 13) 98b is formed in one wall portion.

The connecting wall 98 is provided with the four ribs 9.
A supply member through hole 98a is formed in three of the four wall portions divided into four by 9 and a supply member through hole of the three wall portions is formed in one wall portion. The supply member through-hole 98b having a smaller inner diameter than the inner diameter of the supply member 98a by one turn.
(See FIG. 13). A supply cylinder front end receiving hole 98c having an inner diameter larger than the inner diameter of the supply member through-hole 98b is formed on the rear surface (-X side surface) of the connection wall 98. The supply tube front end receiving hole 98c has the same inner diameter as the supply member through hole 98a, and the supply member through hole 98b and the supply tube front end receiving hole 98c are arranged concentrically.

In FIGS. 11 and 13, the cylindrical member main body 90 is integrated with the front small-diameter outer cylindrical portion 93 and the connecting wall 98 inside the supply developer receiving port 93a of the front small-diameter outer cylindrical portion 93. A replenishment developer receiving section 100 is formed. The replenishment developer receiving section 10
0 is a plane wall 101 disposed in front of the connecting wall 98 at a distance as shown in FIGS.
2 is formed. As shown in FIG. 11, the curved wall 102 is formed so as to become narrower downward from the supply developer receiving port 93a. The flat wall 1
01, a supply member supporting cylindrical portion 101 extending forward.
a is provided, and the inner hole of the supply member support cylindrical portion 101a is concentric with the supply member through-hole 98b and has the same inner diameter.

In FIG. 13, the front end of the developer supply tube 76 is fitted into the supply member support cylindrical portion 101a, and the front end of the developer supply tube 76 is connected to the rear surface (−
(The X-side surface). At this time, a developer carrying inlet 76b (see FIG. 5) at the front end of the developer supply cylinder 76 is connected to the supply member through-hole 98b. The bearing 78 (see FIG. 13) at the front end (the end in the X direction) of the rotation shaft 77a of the supply member 77 for supply that extends forward from the developer carrying-in port 76b of the developer supply cylinder 76 is connected to the supply member support cylindrical portion 101a. It is fitted and supported on the inner peripheral surface. Therefore, the developer supplied to the replenishment developer receiving portion 100 from the replenishment developer receiving port 93a is carried into the developer replenishing cylinder 76 from the developer carrying-in port 76b by the rotation of the replenishment conveying member 77. You. This developer supply cylinder 7
The developer 6 is conveyed rearward (−X-axis direction), and the second developer pool 65 (see FIG. 2, FIG. 3, and FIG. 5) is supplied from the supply port connection portion 76a and the developer supply port 73a (see FIGS. 2, 3, and 5). FIG.
See)). The cylindrical member body 90 of the K cylindrical member Bk has the above-mentioned reference numerals 91 to 102.
It consists of the elements shown by.

In FIGS. 12 and 13, a ring cover 106 is mounted on the outer surface of the large-diameter outer cylindrical portion 92 on the rear side of the cylindrical member main body 90. The ring cover 106 is a member having an L-shaped cross section, and is fixed to the rear large-diameter outer cylindrical portion 92. The K (black) cylindrical member Bk includes the cylindrical member main body 90 and the ring cover 106.
The Y (yellow) cylindrical member By, the M (magenta) cylindrical member Bm, and the C (cyan) cylindrical member Bc are the same as the cylindrical member body 9 similar to the K (black) cylindrical member Bk.
0 and a ring cover 106. The position of each replenishment developer receiving portion 100 of each of the cylindrical members Bk, By, Bm, and Bc is set at 9 degrees around the rotation axis Do.
They are shifted by 0 °.

As shown in FIG. 11, each of the connecting members Ly and L is connected to the developer supply port 86e of the ring-shaped connecting member Lk.
The developer supply ports 86e of m and Lc are arranged in the front-rear direction and are all upward. Therefore, for example, in a state where the replenishment developer receiving portion 100 of the cylindrical member Bk is connected to the developer supply port 86e, the replenishment developer receiving portions 100 of the other cylindrical members Bk, By, Bm, and Bc.
From the position connected to those developer supply ports 86e.
It is positioned at 0 °, 180 °, and 270 ° rotation. Then, as the rotation axis Do rotates by 90 °, the replenishment developer receiving portion 100 of each of the cylindrical members By, Bm, and Bc sequentially moves to a position connected to the developer supply port 86e. .

10 to 14, the discharge cylindrical member Bh is constituted by a cylindrical member main body 90 'having a shape similar to the cylindrical member main body 90 of the K cylindrical member Bk and a ring cover 106. In FIGS. 10 to 14, components that are components of the cylindrical member main body 90 ′ and correspond to components 91 to 98 of the cylindrical member main body 90 are denoted by the same reference numerals with “′” (dash). Explanation is omitted. Cylindrical member main body 90 'of discharge cylindrical member Bh
The four ribs 99, the replenishment developer receiving portion 100, the replenishment developer receiving hole 93a, etc. of the cylindrical member main body 90 of the K cylindrical member Bk are omitted, and the thickness of the connecting member 98 is reduced instead of the connecting wall 98. It has a thick connecting wall 98 '(see FIG. 12). The thicker connecting wall 98 'is formed with four supply member through-holes 98a' having the same inner diameter and four discharge member through-holes 98b '.

The four supply member through holes 98a 'penetrate through the developer supply cylinder 76 (see FIG. 13), and the four discharge member through holes 98b penetrate through the tip of the developer discharge cylinder 71 (see FIG. 13). 2). In addition, the front small-diameter outer cylindrical portion 93
Are formed with a total of four collection container communication ports 93a 'every 90 degrees. The discharge tube connecting portion 69, the developer discharge tube 71, the discharge conveying member 58, the discharge cylindrical member Bh,
A developer discharging device J (J = 69 + 71 + 72 + Bh + Lh) is constituted by the discharging ring-shaped connecting member Lh.

12 and 13, the front cylindrical member Bf is composed of a cylindrical member main body 90 ″ corresponding to the cylindrical member main body 90 of the K cylindrical member Bk and a ring cover 106. The front cylindrical member Bf The cylindrical member body 90 ″ of Bf is the cylindrical member body 9 of the K cylindrical member Bk.
0, the front small-diameter outer cylindrical portion 93, four ribs 99, a replenishment developer receiving portion 100, and a replenishment developer receiving hole 93a.
Are omitted. The cylindrical member main body 90 "has an outer cylindrical portion 91", an inner cylindrical portion 94 ", and a connecting wall 98" connecting the front ends of the outer cylindrical portion 91 "and the inner cylindrical portion 94". The portion 91 "has the same outer diameter as the rear large-diameter outer cylindrical portion 92. The ring plate 106 is fitted on the circumferential side surface of the outer cylindrical portion 91".

The inner cylindrical portion 94 ″ is a front small-diameter inner cylindrical portion 96 ″.
And a rear-side large-diameter inner cylindrical portion 97 ". The inner cylindrical portion 94" is formed with a rotating shaft fitting hole 94a "and a not-shown fixing screw through-hole. Are formed with holes 98a ″. A fixing screw through hole (not shown) of the front cylindrical member Bf, four fixing screw through holes 94c ′ of the discharge cylindrical member Bh, and the K,
The four fixing screw through holes 94c of the cylindrical members Bk, By, Bm, and Bc of Y, M, and C are connected in a straight line, and the fixing screws that pass through the through holes 94c, 94c ', and 94c ". The tip of N2 (see FIGS. 12 and 13) is screwed into a nut (not shown) fixed to the front rotating frame 56.

9 to 15, the fixing screw N2
The cylindrical members B connected to each other by (see FIG. 9)
The developer receiving ports 93a of k, By, Bm, and Bc are arranged so as to be shifted by 90 ° around the axis. Since the positions of the cylindrical members Bk, By, Bm, and Bc are shifted along the rotation axis Do, the positions of the developer receiving ports 93a are also shifted in the direction of the rotation axis Do. For this reason, since the developer carrying-in port 76b at the tip end of each of the developer supply cylinders 76 has a different position in the axial direction, each of the developer supply cylinders 76 has a different shape.
The tip is formed to have a different length in the axial direction.
The developer carrying-in port 76b (see FIG. 5) formed at the tip of each of the developer supply cylinders 76 has a cylindrical member Bk, By, B
It communicates with the developer receiving port 93a through the supply developer receiving section 100 for m and Bc.

For example, the developer replenishing cylinder 76 for replenishing the developer from the replenishment developer receiving portion 100 of the K (black) cylindrical member Bk to the developing container Dk has a front end (X side end) having the above-described configuration. The discharge cylindrical member Bh (see FIG. 13) penetrates the supply member through hole 98a ', and its front end is the K (black).
The supply cylinder front end accommodation hole 98c (see FIG. 13) connected to the supply developer receiving portion 100 of the supply cylinder member Bk. Further, for example, the developer supply cylinder 76 for supplying the developer from the supply developer receiving section 100 of the Y (yellow) cylindrical member By to the developer container Dy has a front end (X
Side end) is a supply member through hole 9 of the discharge cylindrical member Bh.
8a 'and the supply cylinder front end housing which penetrates the supply member through hole 98a of the K (black) cylindrical member Bk and whose front end is connected to the supply developer receiving portion 100 of the Y (yellow) cylindrical member By. It is housed in the hole 98c. The developer supply cylinder 76 is similarly arranged for the cylindrical members Bm and Bc for M (magenta) and C (cyan).

The developer receiving port 93a of each of the cylindrical members Bk, By, Bm, and Bc is connected to each of the ring-shaped connecting members Lk, Ly,
It rotates around the axis in Lm and Lc and communicates with the developer supply ports 86e (see FIG. 11) of the ring-shaped connecting members Lk, Ly, Lm and Lc. A new two-component developer falling from the developer receiving port 93a for each toner color is carried into the developer receiving port 76b (see FIG. 5). The rotating cylindrical members Bh, Bk, By, B
m, Bc and each of the fixedly supported ring-shaped connecting members L
The space between h, Lk, Ly, Lm, and Lc is a seal member 88.
Is sealed for each of the cylindrical members Bh, Bk, By, Bm, and Bc, so that the cylindrical members Bh, Bk, By, Bm, and Bm are supplied when a new two-component developer is supplied or surplus developer is discharged.
Bc and each ring-shaped connecting member Lh, Lk, Ly, Lm, Lc
Is prevented from moving toward another cylindrical member.

In FIGS. 14 and 15, a developer supply case K is disposed above the fixed cylindrical member F1a. The developer supply case K includes developer storage containers 111 k, 111 y, and 111 in which two-component developers including K (black), Y (yellow), M (magenta), and C (cyan) toners and carriers are stored. 111m, 111c and developer stirring containers 112k, 112y, 112 provided therebelow.
m, 112c. Developer storage container 111k, 1
11y, 111m, 111c to developer stirring container 112k,
The two-component developer supplied to 112y, 112m, and 112c is a developer stirring container 112k, 112y, and 112c, respectively.
It is stirred while circulating in m, 112c. The two-component developer stirred in the developer stirring containers 112k, 112y, 112m, and 112c is connected to pipe connection holes 113k, 113y, and 1c.
13m, 113c to developer conveying pipes 114k, 114
y, 114m and 114c.

The developer transport pipes 114k, 114
y, 114m and 114c each have a transport screw 1
16 is rotatably arranged, and is rotatably driven by motor units 117k to 117c arranged at the ends of the developer transport pipes 114k, 114y, 114m, 114c. Each of the developer conveying pipes 114k, 114y,
The developer storage containers 111k, 111y, 111m, 111c are rotated by the rotation of the conveying screws 116 of 114m, 114c.
The new two-component developer is transported to the developer supply port 86e. Reference numerals 76 to 117, Lk
The developer supply device T (FIG. 4, FIG. 14, FIG. 15 minimum) is constituted by the components indicated by Lc, Lh, Bk to Bc, Bf, Bh, K. The gears G6, G7, G9, G1
A supply member driving device TDh for supply is constituted by 1 to G14.

In FIG. 15, the pipe connection hole 113
y, 113m, 113c are linearly arranged on one side (right side) of the four developer supply holes 86e arranged on one straight line, and only four pipe connection holes 113k are arranged on one straight line. It is arranged on the opposite side (left side) of the developer supply hole 86e. As can be seen from FIG. 14, the developer storage containers 111k, 111y, 111m, and 111c have the same configuration, and only the developer storage container 111k is different from the other developer storage containers 111y, 111m, and 111c. It is arranged in a state rotated by 180 ° around the Z axis. Therefore, the pipe connection holes 113k, 113y, 113
m, 113c, the developer is conveyed from the developer supply hole 86e to the right (−Y
Direction) and the other developer conveying pipes 114y, 114
m and 114c indicate the left direction (Y direction). The developer conveying pipes 114k, 114y, 114m, and 114c are arranged in parallel with each other.

As described above, each developer storage container 111
By using the same configuration for k, 111y, 111m, and 111c, it is possible to reduce the number of component types and to save manufacturing costs. Further, as described above, the developer transport pipe 11
By arranging the 4k, 114y, 114m, and 114c parallel to each other, the assembling work can be facilitated. In the present embodiment, the developer supply holes 86e and the pipe connection holes 113k, 113y, 113m,
Developer transport pipes 114k and 114 connecting the 113c
In order to arrange y, 114m and 114c parallel to each other,
The direction in which the developer supply holes 86e are arranged (front-back direction, X-axis direction)
To the pipe connection holes 113k, 113y, 113
The directions in which m and 113c are arranged (that is, the directions in which the developer storage containers 111k, 111y, 111m, and 111c are arranged) intersect.

(Operation of Embodiment) An image carrier on which an electrostatic latent image is written by a ROS (optical writing scanning device, ie, a latent image writing device, image writing device) at a latent image writing position Q1. Reference numeral 16 moves to the development area Q2. The developing device supporting member H rotatably supported by the front fixed frame F1 and the rear fixed frame F2 is disposed adjacent to the surface of the image carrier 16 in the developing area Q2. The plurality of developing devices Dk, Dy, Dm, and Dc supported by the developing device support member H are:
A first stop position (development position, developer supply position, developer discharge position) P for developing the latent image on the surface of the image carrier 16 into a toner image with the rotation and stop of the developing device support member H
1. The movement is sequentially stopped at the second stop position P2, the third stop position P3, and the fourth stop position P4.

(Operation at First Stop Position P1) In FIG. 4, the gear G7 supported by the developing container 61 of the developing devices Dk, Dy, Dm and Dc stopped at the first stop position P1 (see FIG. 2). And a gear G6 coaxial with the gear G14 meshes with a gear G14 supported by the fixed frame F2. The gears G6 and G7 are rotated by the rotation of the gear G14, and the gear G8 meshes with the gear G7 and the gear of the second transport member R2 (not shown).
And the gear G9 also rotates. The rotation of each gear rotates the developing roll R0, the first stirring and conveying member R1, the second conveying member R2, the replenishing conveying member 77, and the discharging conveying member 72. The rotation of these members causes the first stop position P
At 1, the following operation is performed.

(1) Developing Operation In the developing container 61, a developer stirring and conveying member (R
1 + R2) supplies the developer to the developing roll R0. The developing roll R0 conveys a two-component developer composed of a toner and a carrier to a developing area Q2 facing the surface of the image carrier 16. At this time, the electrostatic latent image on the surface of the image carrier 16 is developed into a toner image by the toner conveyed. By this developing operation, the toner in the developing container 61 is consumed and reduced, and the carrier is contaminated and deteriorated. The two-component developer having the carrier and the toner is supplied, but the carrier is not consumed, so that the amount of the two-component developer in the developing container 61 increases. In particular, when a single color continuous copy is performed, the amount of the developer rapidly increases. Therefore, it becomes necessary to discharge the deteriorated two-component developer including the carrier.

(2) Developer discharging operation The first and second developer pools 64 and 65 are transported by the rotation of the first stirring and transporting member R1 and the second transporting member R2, and the first and second developer transporting members R1 and R2 are conveyed. Second developer pool 64, 65
The developer circulates through the developer outlet 68 to discharge the developer. At this time, since the developer is discharged in a state where the developer discharge port 68 is disposed in a vertical plane, the developer at a position higher than the height of the lower end position of the developer discharge port 68 is discharged. become. That is, if the upper end of the developer is lower than the height of the developer outlet 68, the developer is discharged from the developer outlet 68.
Will not be discharged from Therefore, only the surplus developer is discharged.

The discharged surplus developer is supplied to the developer discharge cylinder 71.
A collection container communicating portion 7 which is a tip (that is, a front, X direction) portion of the developer discharge cylinder 71 by a discharge conveying member 72 in the inside.
Transported to 1b. The conveyed surplus developer is discharged from the collection container communicating portion 71b into the discharge cylindrical member Bh. 10 and 12, the excess developer discharged into the discharging cylindrical member Bh is connected to the collecting container of the discharging ring-shaped connecting member Lh through a collecting container communication port 93a 'formed in the discharging cylindrical member Bh. The developer is discharged to the developer collecting container V through the port 86g 'and collected.

(3) Developer Supply Operation The developer storage containers 111k and 111 of the developer supply case K
The developer of y, 111m, 111c (see FIGS. 14 and 15) is supplied to each of the developer conveying pipes 114k, 114y, 114m,
The ring-shaped connecting members Lk, Ly, Lm,
Lc is transported to each developer supply port 86e (see FIGS. 11 and 14). The developer supply port 86e is connected to the cylindrical member Bk,
Any one of the developer receiving ports 93a of By, Bm, and Bc.
And a developer carrying port 7a through the developer receiving port 93a.
6b (see FIG. 5) and is supplied into the developer supply cylinder 76. The supplied developer is conveyed to the developer supply port 74 (see FIG. 6) of the developing container 61 by the rotational driving of the supply conveying member 77 in the developer supply cylinder 76. When the developer amount set according to the consumption amount of the developer is replenished into the container, the transport screw 11 of the developer supply case K
6, the supply of the developer into the developer supply port 76 is stopped.

(4) Supplying developer transport operation FIG. 7 is a diagram for explaining the operation when the supply opening shutter is opened.
FIG. 7A illustrates a state before the supply port shutter is opened, and FIG. 7B illustrates a state where the supply port shutter is opened. 8A and 8B are diagrams illustrating the operation of the operation member, FIG. 8A is a diagram illustrating a state in which the supply port shutter is closed, and FIG. 8B is a diagram illustrating a state in which the supply port shutter is open. 9A and 9B are explanatory views of the operation when the supply port shutter is closed, FIG. 9A is a view showing a state before the supply port shutter is closed, and FIG. 9B is a view showing a state where the supply port shutter is about to be closed.

In FIG. 7, when the rotation shaft 77a of the supply member 77 for rotation rotates, the conveyance blades 77b on the outer periphery of the rotation shaft 77a rotate so that the developer in the developer supply cylinder 76 (see FIG. 6) is removed. Rear (-X direction) supply cylinder connecting portion 76
conveyed to a. The rotating shaft 77a of the supply member 77 for replenishment
, The closing member engaging pin Hp fixed to the rotating shaft 77a rotates. The rotating closing member engaging pin Hp is engaged with the shaft portion 83d of the closing moving member 83, and the closing member engaging pin Hp moves the closing moving member 83 to the right (-Y direction) of the developing container 61. ). The shutter unit 8 closing the communication passage 79a of the communication member 79 shown in FIG.
2 also the slit 79 for shutter guide of the communication member 79
along the right side (−Y direction), that is, the opening position (FIG. 7B
See). When the shutter 82 comes to the open position, the tip of the closing member engaging pin Hp that engages with the shaft 83d rotates around the axis, and when the tip moves upward (in the Z direction), the shaft 83d also tries to move upward.

However, each of the guided portions 83b formed integrally with the shaft portion 83d is a guide member 81b.
Is restricted from moving upwards,
The closing moving member 83 of the guided portion 83b does not move upward. Therefore, the closing engagement pin Hp is disengaged from the shaft portion 83d, and the closing moving member 83 is pulled by the tension spring 84, which is locked by the closing moving member 83,
The shutter 82 is pulled rightward (−Y direction) of the developer supply cylinder 76 by being pulled to the left (Y direction) by 84.
Moves to the left (Y direction) along the shutter slide surface 74b of the shutter engaging member 74 disposed at
By being engaged with the engaging portion 74a (shown by a broken line in FIG. 7B), the open state of the communication passage 79a of the communication member 79 is maintained. At this time, as shown in FIGS. 8B and 9A, the operating pin Pi fixed to the rear fixed frame F2 is engaged with the pin engaged surface 83f on the rear end side of the shaft portion 83d. After the developer amount set in accordance with the consumption amount of the developer is supplied to the container and the supply of the developer into the developer supply port 76 is stopped, the supply member 77 for supply rotates for a predetermined time. The closing member engaging pin Hp fixed to the rotating shaft 77a detects that the proximity switch Sk has passed the rotating closing member engaging pin Hp, and the rotating closing member engaging pin Hp is detected.
For example, p is stopped at a predetermined position shown in FIG. In the illustrated position shown in FIG. 3, when the shutter portion 82 moves from the open position to the closed position, the closing member engaging pin Hp does not engage with the shaft portion 83d, so that the closing movement supporting the shutter portion 82 is performed. The movement of the member 83 does not stop halfway, and the shutter 82 is connected to the communication passage 49a.
Is completely closed.

The transported developer is supplied from the supply port connecting portion 76a of the developer supply cylinder 76 to the communication path 7 of the communication member 79.
The developer is supplied into the developing container 61 from the developer supply port 73 through 9a. Further, even when the developer is transported before the communication path 79a is opened by the shutter 82, the transported developer is temporarily removed from the shutter 82.
Is accumulated on the upper surface of the right wall 79r, and is moved down by the right wall 79r when the shutter portion 82 moves through the shutter guide slit 79b of the right wall 79r. Since the developer supply port 74 is disposed adjacent to the downstream side of the developer discharge port 68,
The developer supplied from the developer supply port 74 is transported away from the developer discharge port 68. Therefore, the replenished new developer is not immediately discharged from the developer discharge port 68. That is, the developer discharged from the developer discharge port 68 is a developer containing a large amount of deteriorated developer.

(Operation When Moving to Second Stop Position P2) In FIGS. 8 and 9A, the developer container 61 stopped at the first stop position P1 is moved from the first stop position P1 to the second stop position P2. , The operating pin Pi engages with the pin engaged surface 83f on the rear end side of the closing moving member 83. As a result, as shown in FIG. 9A, the communication member 7 of the shutter portion 82 engaged with the shutter engagement member 74
The 9 side (left side (Y direction) side) is lifted up and disengages from the engaging portion 79a of the shutter engaging member 74. The shutter 82 and the closing moving member 83 are connected to the tension spring 8.
4, the shutter 82 and the closing moving member 83 move leftward (in the Y direction), which is the direction of the closing position, to move the communication member 79.
Is closed, and the developer supply port 73a is also closed. Therefore, the second, third, fourth
At each stop position, the communication passage 79a (including the developer supply port 73a) of the communication member 79 is closed.

Since the shutter portion 82 is urged to the closed position by the tension spring 84, the developer replenishing port is provided even if the weight of the developer is applied by the impact or the rotating position when the developer container 61 is rotationally moved. 73a does not open. Therefore, when the developer container 61 rotates, it flows out of the developer supply port 73a, and the developer supply cylinder 7
No backflow to 6. Further, the shutter portion 82 is moved to the open position by the closing engagement pin Hp fixed to the rotating shaft 77a of the supply member 77, and is moved to the closed position by the operation pin Pi when the developing container 61 is rotated. Since it returns, a power source for operating the shutter portion 82 is not required. Further, at the first stop position P1, the developer supply port 73a is opened to supply new developer into the developing container 61 and discharge the developer from the container at the same time. For this reason, even if a large amount of the developer in one developing container 61 is used in a single color continuous copy, a new developer and a deteriorated developer are supplied and discharged at the same time.
The amount of developer in 1 is kept within a specified amount.

(Modifications) Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above-described embodiments, but falls within the scope of the present invention described in the appended claims. Thus, various changes can be made. Modified embodiments of the present invention will be exemplified below. (H01) The developer supply position can be set at a position other than the first stop position P1. (H02) The present invention can be applied to analog copying machines, printers, facsimile machines, etc., in addition to digital copying machines. (H03) When the developer storage containers 111k and 111y are disposed symmetrically with respect to the four developer supply holes 86e on the one straight line, the developer transport pipes 114k and 114y
14y can be of the same configuration.
Also in this case, it is possible to reduce the number of parts. Further, the developer storage containers 111k, 111y, 111
m, 111c are connected to the four developer supply holes 86e on the straight line.
(The developer supply hole 86e)
111k and 111y are placed on the left side of the
111c), the developer transport pipes 114k and 114c can have the same configuration, and the developer transport pipes 114y and 114m can have the same configuration. In this case, there are two types of developer transport pipes, and the number of parts can be further reduced.

[0096]

The developing device of the present invention described above has the following effects. (E01) Open the shutter of the developing device stopped at the stop position (developer supply position) for supplying the developer, and move the developing device moved to a position other than the stop position (developer supply position) for supplying the developer. The shutter can be closed. Therefore, even if the rotation of the developer container is stopped at a position other than the developer supply position or the developer container is detached from the developing device, the developer in the container can be prevented from flowing out from the developer supply port of the developer container. The shutter member can be operated mechanically without specially providing a power source for operating the shutter. (E02) At the developing position, the developer can be supplied to the developing containers of the plurality of developing devices.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an entire image forming apparatus provided with a developing device according to an embodiment of the present invention.

FIG. 2 is an enlarged explanatory view of a main part of FIG. 1;

3 is a cross-sectional view of the developing container at the developing position in FIG. 2; FIG. 3A is a diagram showing a state in which a supply port shutter is closed in the developing container in the developing position in FIG. 2; FIG.
FIG. 10 is a diagram illustrating a state in which the supply port shutter is opened in the developing container at the developing position.

FIG. 4 is a diagram illustrating a state in which the developing device of the embodiment is mounted on a rotating developing device support member.

FIG. 5 is a perspective view of the developing container of the embodiment.

FIG. 6 is a perspective view of a shutter operating device.

7A and 7B are explanatory diagrams of the operation when the supply port shutter is opened, FIG. 7A is a view showing a state before the supply port shutter is opened, and FIG. 7B is a view showing a state where the supply port shutter is opened.

8A and 8B are explanatory diagrams of the operation of the operation member. FIG. 8A is a diagram illustrating a state in which the supply port shutter is closed, and FIG. 8B is a diagram illustrating a state in which the supply port shutter is open.

9 is a diagram illustrating the operation when the supply port shutter is closed, FIG. 9A is a view showing a state before the supply port shutter is closed, and FIG. 9B is a view showing a state where the supply port shutter is about to be closed; It is.

FIG. 10 is a sectional view taken along line XX of FIG. 4;

FIG. 11 is a sectional view taken along the line XI-XI in FIG. 4;

12 is an explanatory view of a developer replenishing device of the developing device, and is a cross-sectional view taken along line XII-XII in FIG.

FIG. 13 is a sectional view taken along line XIII-XIII in FIG.

FIG. 14 is an explanatory diagram showing a positional relationship between a developer supply case and a developer supply device.

FIG. 15 is a view as seen from the direction of arrow XV in FIG. 14;

[Explanation of symbols]

Bk, By, Bm, Bc: rotating cylindrical member, F1, F2: fixed frame, F1a: fixed cylindrical member, Do: rotating shaft, Dk, D
y, Dm, Dc: developing unit, H: developing unit supporting member, Hb: developer discharging member, JD: discharging conveying member driving device, P1: first stop position, Pi: operating member, Q2: developing area, R0 ... Developing roll, (R1 + R2) ... Developer stirring and conveying member, ROS
... Image writing device, SD ... Shutter actuating device, TD ... Replenishing conveyance member driving device, Th ... Developer replenishing member, V ... Developer collecting container 16 ... Image carrier, 41 ... Developing container, 61 ... Developing container 6
Reference numeral 8: developer discharge port, 72: discharge conveyance member, 73a: developer supply port, 76: developer supply cylinder, 76a: supply port connection portion, 76b: developer carry-in port, 77: supply conveyance member, 8
2: Supply port shutter, 83: moving member for closing, 86e ...
Developer supply port, 88: ring-shaped seal member, 93a: supply developer receiving port, 100: supply developer receiving section,
111k, 111y, 111m, 111c: developer storage container, 116: transport screw,

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Shigemi Murata 2274 Hongo, Ebina-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Hirohisa Kono 2274 Hongo, Ebina-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd.

Claims (3)

[Claims] 1. A developing device having the following requirements: (A01) a surface of an image carrier on which latent images of a plurality of color components corresponding to image information are written and rotated by an image writing device. A developing device support member having a rotating shaft rotatably supported by a fixed frame and supporting a plurality of developing devices, and (A02) rotating and stopping the rotating shaft to A plurality of developing devices, a first stop position for developing a latent image of each color component on the surface of the image carrier into a toner image of each color;
The developing device supporting member which is sequentially stopped at each of the stop positions rotated by 270 ° and 270 °; (A03) a developer supply port for replenishing new developer and a developer discharge port for discharging surplus developer; A developing container for storing a two-component developer comprising a toner and a carrier, a developing roll for transporting the two-component developer to a developing area adjacent to the surface of the image carrier when moved to the first stop position; A developer stirring / conveying member for supplying the developer to the roll; and a replenishing conveying member for conveying the new developer to the developer replenishing port. A developer discharge member having a developer supply member, a supply port shutter for opening and closing the developer supply port, and a discharge conveyance member for conveying the developer discharged from the developer discharge port toward a developer collection container; And (A05) actuating the replenishing transport member of the developing device stopped at a predetermined stop position set at a developer replenishing position for replenishing developer to the developing container. (A06) The replenishing port shutter is opened in mechanical linkage with the operation of the replenishing transporting member, and replenished when the developing device moves from the developer replenishing position to another position. A shutter operating device that closes the mouth shutter. 2. The developing device according to claim 1, further comprising: (A07) the developer supply position set at the first stop position. 3. The developing device according to claim 1, wherein the developing device stopped at the developer replenishing position is rotated by rotation of the developing device supporting member. A shutter moving member which moves by engaging with an operating member supported by the fixed frame when moving from the agent supply position, and closing the shutter when moving by engaging with the operating member; apparatus.