JPH09185258A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent developer which has fallen from sticking onto a transfer material by providing a developer receiving member, and receiving developer which is discharged from a developing area and falls by itself toward a transfer- material carrying path which is below it. SOLUTION: An opening which faces a photoreceptive drum is made in the casing of each developing device, and a developing roller 84 is provided in a developing chamber so that a part of it is exposed via this opening. A toner receiving member 330 as the developer receiving member, so composed of a rigid body as to cover the periphery of the developing unit which is below the opening of the developing device, is detachably fixed to a storage base 46 with a fixing screw. By the provision of the toner receiving member 330, even in case toner falls onto a carrying belt from the opening of the developing device, the toner is received by the toner receiving member before reaching the surface of the carrying belt. Therefore, it does not reach the surface of transfer paper which is carried in a place lower than the opening of the developing device, and soil on the transfer paper with toner which has fallen can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile and a printer.

[0002]

2. Description of the Related Art Conventionally, as this type of image forming apparatus,
A latent image is formed by rotating a developing unit having a plurality of developing units arranged around the rotation center line, and moving each developing unit to a developing position facing the latent image carrier. An image forming apparatus including a rotary developing device that develops a latent image on a carrier is known.

[0003]

However, in the rotary developing device of the image forming apparatus described above, the developer floating in the developing device is partially exposed, for example, from the opening of the developing device case due to the use over time, and the latent image is generated. In a region facing the image carrier, the developer is conveyed in a predetermined direction and adheres or accumulates on a wall of a developing device or the like above the developer supply member that supplies the developer to the latent image carrier. Then, the developer drops as a lump on the developer supply member due to impact or vibration generated due to the rotation of the developing device unit, and the developing device is rotated by centrifugal force due to the rotation of the developing device unit. It may be discharged to the outside. Here, in the case where a transfer material conveying device is provided so as to convey the transfer material that transfers the developed image of the latent image carrier or the transfer material that transfers the developed image below the developing device unit, the developing device When the discharged developer falls due to its own weight, a toner drop image occurs due to the dropped developer adhering to the transfer material, or a developer having a color different from the color of the image formed on the transfer material. However, there is a problem in that a mixed color image is generated by falling and adhering to the transfer material.

For example, when a developing device is used in which a magnetic developer is used as the developer and the magnetic developer is supplied to the latent image carrier by a developer supply member having a magnet inside, the developer is supplied. The developer carried on the portion of the member where the magnetic force is weak may be discharged to the outside of the developing device due to the rotation of the developing device unit. When such developer discharging occurs, the developer inside the image forming apparatus Contaminated with
There is also a problem in that it attaches to the drive system and causes abnormal noise.

The present invention has been made in view of the above problems, and an object thereof is to contaminate the inside of the device with the developer discharged to the outside of the developing device as the developing device unit rotates. , Prevents the toner from adhering on the transfer material conveyed by the transfer material conveying device below the developing unit,
An object of the present invention is to provide an image forming apparatus capable of preventing the occurrence of a toner drop image.

[0006]

In order to achieve the above object, the invention of claim 1 comprises a latent image carrier on which a latent image is formed, and a plurality of developing devices arranged around a rotation center line. A rotary developing device for rotating the developing device unit having the developing device unit, and moving each developing device to a developing position facing the latent image carrier to develop the latent image on the latent image carrier. ,
In the image forming apparatus including a transfer material for transferring the developed image of the latent image carrier or a transfer material transfer device for transferring the transfer material on which the developed image is transferred, the transfer material is moved to the developing position. From a region of a certain developing device, which is partially exposed from a developing device case opening for supplying the developer to the latent image carrier, to the developing device unit, from a region facing the latent image carrier. And a developer receiving member for receiving the developer falling toward the transfer path of the transfer material transfer device located below the.

According to the first aspect of the present invention, the development is such that the developer supply member for supplying the developer to the latent image carrier and the latent image carrier face each other as the developing device unit rotates. The developer receiving member receives the developer discharged from the area to the outside of the developing device and dropped by its own weight toward the transport path of the transfer material transport device located below the developing area in the developing device unit. As a result, while the transfer material that transfers the developed image on the latent image carrier or the transfer material that has transferred the developed image is transported through the transport path, the dropped developer adheres to the transfer material. Prevent that.

Particularly, in the invention of claim 2, in the invention of claim 1, the developer receiving member is formed separately from the member of the main body of the image forming apparatus, and the latent image bearing is carried on the developer receiving member. It is characterized in that a seal member is provided to seal a gap between the developer receiving member and the image forming apparatus main body side member that is close to the body side.

Here, by forming the developer receiving member separately from the member of the image forming apparatus main body, for example, the developing device unit is taken out from the image forming apparatus main body and the developer contained in each of the developing devices is stored. Can be easily replaced.

According to the second aspect of the present invention, since the developer receiving member is formed separately from the member of the image forming apparatus main body, an image which is close to the developer receiving member from the latent image carrier side. A gap is formed between the member on the main body of the forming apparatus and the developer receiving member. Therefore, by sealing this gap with a seal member, it is possible to prevent a part of the developer that has dropped below the developing area from dropping onto the transfer material through the gap.

According to a third aspect of the present invention, in the first aspect of the invention, a developing device unit support for supporting the developing device unit in the main body of the image forming apparatus is provided, and the developing device unit support is provided in the longitudinal direction. In order to increase the strength, the developer receiving member is provided on the developing device unit support.

According to another aspect of the present invention, the developer receiving member provided on the developing device unit support for supporting the developing device unit in the main body of the image forming apparatus is the longitudinal direction of the developing device unit support. By exhibiting the function of increasing the strength of the developing device unit support, the developing device unit support is prevented from being twisted or bent due to its own weight.

In particular, a fourth aspect of the present invention is the invention of the first aspect, further comprising a developing device unit support for rotatably supporting the developing device unit, and a predetermined first position on the developing device unit support. A developer collecting container is attached to the opening for collecting developer contained in the developing device in the rotating position, and the developing device with the developer collecting container is attached to a predetermined second rotation position on the developing device unit support. And is configured to collect the developer in the developer collecting container through the opening, and collects the developer during rotation of the developing unit from the first rotation position to the second rotation position. The developer receiving member is detachably attached to a position overlapping the path along which the container moves.

According to another aspect of the present invention, the developing unit located at the first rotation position during the rotation of the developing unit from the predetermined first rotation position to the second rotation position on the development unit support. Toner transferred from the developing area onto the transfer material during the developing operation is performed by the developer receiving member provided at a position overlapping the moving path of the developer collecting container attached to the developer collecting opening of the container. To prevent falling. Further, at the time of the developer replacement work, by removing the developer receiving member, the developer accumulated in the developer receiving member can be cleaned, and the most recoverable development can be performed from the opening of the developing device. The developer can be collected at the agent collecting position.

According to a fifth aspect of the invention, a latent image carrier on which a latent image is formed, and a developing device unit having a plurality of developing devices arranged around the rotation center line are provided around the rotation center line. In an image forming apparatus equipped with a rotary developing device that rotates and moves each developing device to a developing position facing the latent image bearing member to develop the latent image on the latent image bearing member, A guide member that receives the developer scattered from the developing device case opening of the developing device by the centrifugal force when rotating and collects it in the lower part is arranged on the outer periphery of the developing device unit. It is a feature.

In the invention of claim 5, the guide member disposed on the outer periphery of the developing device unit is developed from the developing device case opening of the developing device by centrifugal force when the developing device unit rotates. The developer scattered to the outside is received, and the developer is guided so as to move downward by its own weight. Then, the developer moved by its own weight is collected under the guide member.

In particular, the invention of claim 6 is characterized in that, in the invention of claim 5, wherein a magnetic developer is used as the developer, at least a part of the guide member is constituted by using a magnet. is there.

In the sixth aspect of the invention, the magnetic developer scattered from the developing device case opening to the outside of the developing device is attracted to the guide member side by the magnetic force of the magnet used for the guide member. Further, the magnetic developer attracted to the guide member side is securely held in the guide member by the magnetic force of the magnet, and does not scatter to the outside of the guide member even when subjected to vibration from the outside, for example. To do so.

[0019]

DETAILED DESCRIPTION OF THE INVENTION An embodiment in which the present invention is applied to a color electrophotographic printer (hereinafter referred to as a printer) which is an image forming apparatus will be described below. FIG. 1 is a schematic configuration diagram of a printer according to the present embodiment. First, an outline of the entire printer will be described. In FIG. 1, a photosensitive drum 1 as a latent image carrier is uniformly charged by a charging charger 2 as a uniform charging unit while being driven to rotate in the direction of arrow A, and then image information is formed by a laser optical device 3. And an electrostatic latent image is formed on the surface. Here, the image information to be exposed is monochromatic image information obtained by decomposing a desired full-color image into yellow, magenta, cyan, and black color information. The electrostatic latent image formed on the photoconductor drum 1 is developed by the rotary developing device 4 described later with yellow, magenta, cyan, and black toners as predetermined developers, respectively. An image of each color is formed on.

Each color image formed on the photosensitive drum 1 is transferred to the intermediate transfer belt 5 rotating in the direction of arrow B in FIG. 1 in synchronization with the photosensitive drum 1 by a single color of yellow, magenta, cyan, and black. Are sequentially superimposed and transferred by the primary transfer charger 6. The yellow, magenta, cyan, and black images superimposed on the intermediate transfer belt 5 are transferred from a double-sided copying / automatic paper feed cassette 7 or a manual paper feed tray 7a via paper feed rollers 8, 8a and registration rollers 9 to a transfer unit. Are collectively transferred by a secondary transfer charger 11 onto a transfer paper 10 as a transfer material conveyed to the printer. The transfer paper 10 after the transfer is conveyed on a conveyance belt 15 as a transfer material conveyance device disposed below the rotary developing device 4, where the toner image is fixed by the fixing device 12, and discharged out of the apparatus as a full color print. You.

The toner on the photoconductor drum 1 that has not been transferred onto the intermediate transfer belt 5 is removed by the photoconductor cleaner 13.
Is removed from the photosensitive drum 1 by the
The toner on the intermediate transfer belt 5 that has not been transferred onto
It is removed from the intermediate transfer belt 5 by the intermediate transfer belt cleaner 14.

Next, the rotary developing device according to this embodiment will be described. 2 is an exploded perspective view of the developing device, FIG.
FIG. 4 is a sectional view showing the internal structure of the developing device unit 40 of the developing device, and FIG.
9 is a sectional view taken along a plane including a central axis 52 of 91. FIG. In FIG. 2, the rotary developing device has a developing device for each of four colors, for example, black, cyan, yellow, and magenta formed therein, and has a substantially cylindrical outer periphery that is attached rotatably around the central axis in the printer body. And a four toner container 41, 42, 43, 44 corresponding to each developer in a one-to-one correspondence and containing toners of black, yellow, magenta, and cyan, respectively. A toner container unit 45 which is attached so as to be substantially coaxial with the front side of the central axis with respect to 40 and rotates integrally with the developing unit 40 around the central axis.
In the state in which the developing device unit 40 and the toner container unit 45 (hereinafter, referred to as a revolver developing unit) are carried, an accommodating stand 46 slidable on the printer body substantially parallel to the central axis, and the toner container unit. A cover 47 is provided on the front support plate 48 of the storage base so as to cover 45, and the cover 47 is non-rotatably provided.

The revolver developing unit is provided with a receiving table 46.
Rotatably attached to the front support plate 48 of, for example, 2
One support roller 49 supports the disk-shaped front end wall 50 of the developing device unit 40, and the central axis 5 of the tip taper projectingly provided at the center of the disk-shaped rear end wall 51 of the developing device unit 40.
2 is rotatably supported by the central shaft insertion hole 54 formed in the rear plate 53 of the main body, so that the rotation axis of the printer 2 becomes the rotation axis of the photosensitive drum 1 in the printer main body as shown in FIG. They are positioned so as to be parallel to each other in substantially the same horizontal plane and are rotatable.

First, the mechanism for rotatably supporting the revolver developing device unit 40 will be described with reference to FIG. In FIG. 2, the accommodation base 46 includes the front support plate 48, the rear support plate 55, and a side cover 59 having front and rear end portions fixed to both support plates and reinforced by connecting rods 56, 57 and 58. Have. The side cover 59 has a notched portion 59 formed by notching a hatched portion in the drawing.
a is formed. As will be described later, the side surface cover 59 also functions as a guide member that prevents the developer scattered from the developing device. An insertion hole 60 into which the developing device unit 40 can be inserted is formed in the front support plate 48, and in addition to the support roller 49, a motor 61 for driving a toner replenishing roller provided in the toner container unit 45 and A gear train driven by the motor 61 is attached. An intermediate plate 63 is attached to the connecting rods 56 and 57 near the rear support plate 55.
A positioning pin 63b that fits into a positioning hole 63a formed in the rear side plate of the main body is provided on the reference numeral 3. The middle plate 63
A base end portion of a bracket 64 holding a rotary positioning roller 66 is swingably attached to a positioning pin portion between the rear support plate 55 and the rear support plate 55. And this bracket 6
The reference numeral 4 designates a spring 67 in a direction in which the roller 66 is fitted into a recessed portion 65 formed at a predetermined position (a total of four positions corresponding to each of the four developing devices in the present embodiment) on the peripheral surface portion of the developing device unit rear end wall 51. Is urged by.

The developing unit 4 is provided on the front plate 68 of the main body.
An insertion hole 69 and the like into which the accommodating base 46 carrying 0 is inserted are formed, and a vertical direction for slidably supporting the accommodating base 46 between the main body front side plate 68 and the main body rear side plate 53. Guides 70 and 71 are hung.
Guided portions 72 and 73 are provided at the upper end and side portions of the side cover 59 of the storage table 46, respectively, as the receiving base portion guided by these guides 70 and 71, and the guided portion 73 on the side portion thereof is provided. A guide pin groove 75 into which the guide pin 74 planted upward in the guide 71 is inserted is formed on the lower surface of the guide 71. The pin groove 75 allows the accommodation base 46 to escape in the direction of separating from the photoconductor drum 1 at the time of inserting or withdrawing the accommodation base 46 into the printer main body, and at a predetermined position relatively close to the photoconductor drum 1 when the insertion is completed. In order to guide the developing device unit 40, only a predetermined portion on the front side is bent from the middle so that it is closer to the photosensitive drum 1 than the rear portion.

In the above supporting mechanism of the developing unit 40, when the main body of the accommodating base 46 is inserted, the tapered tip end of the positioning pin 63b projecting from the intermediate plate 63 completes the insertion of the accommodating base into the printer main body. Immediately before entering the positioning hole 63a of the rear plate 53 of the main body, when the insertion is completed,
The rear support plate 55 and the bracket 63 of the accommodation table 46 are accurately positioned in the main body. Further, in the pulled-out state of the accommodating base 46, the rear end portion of the developing device unit 40 supported by the rear side plate 53 of the accommodating base 46 has the tapered central axis 52 just before the completion of insertion of the main body of the accommodating base 46. It is lifted as it gradually enters the central shaft insertion hole 54, and completely lifts from the rear support plate 55 when the insertion is completed. The front support plate 48 of the accommodation table 46 is the accommodation table 4
6 is inserted into the main body, the front plate 6
It is fixed to 8. As a result, the developing unit 40 is
The front end portion is supported by the support roller 49 of the housing base front support plate 48 that is accurately positioned on the main body, and the rear end portion is rotatably positioned on the main body rear side plate 53 via the central shaft 52,
It becomes rotatable.

Further, in a state in which the accommodation table 46 is pulled out to the front side of the apparatus main body, the front end wall 50 of the developing device unit 40 is rotatably supported by the support roller 49 of the accommodation table front support plate 48,
Further, since the rear end wall 51 of the developing device unit 40 can be rotatably supported by the rear support plate 55 of the accommodating base and the developing device unit 40 can be rotatably held, the developing device unit 40 described later will be described.
It is possible to favorably perform the developer replacement work for each developing device while appropriately rotating the developing device in this pulled-out state. In order to allow the developing device unit 40 to rotate more smoothly in this pulled-out state, the same supporting roller as that on the front side may be used to support the rear supporting plate 55 of the accommodating base.

A revolver drive gear driven by a revolver rotation motor (not shown) such as a stepping motor is attached to the main body rear side plate 53 for driving the rotation of the developing device unit 40. This meshes with a revolver input gear having substantially the same diameter as that of the rear end plate 51 fixed to the rear surface of the rear end plate of the developing device unit 40 by screws or the like, and rotationally drives the developing device unit 40.

Next, the developing unit 4 will be described with reference to FIGS.
0 main body will be described. Referring to FIG. 3, the developing device unit 40 includes the front and rear end plates 50 and 51 having the substantially disk shape described above.
It has a partition wall between them. This partition wall has a hollow cylindrical portion 82 into which a cylindrical black toner bottle containing black toner can be inserted, and a partition wall extending radially from the hollow cylindrical portion 82 so that the space around the hollow cylindrical portion 82 is substantially in the circumferential direction. The developing device casing sections 83, 83C, 83M, and 83Y are divided into four developing chambers of the same type. Each of the developing chambers contains a two-component developer composed of a carrier as a developer and toner of each color. In the example shown in the drawing, the developing chamber of the black developing device containing the black toner and the carrier is located at the developing position opposed to the photosensitive drum, and the developing device of the yellow developing device containing the yellow toner and the carrier is arranged in the counterclockwise direction in the figure. A developing chamber is a developing chamber of a magenta developing device containing magenta toner and a carrier, and a developing chamber of a cyan developing device containing cyan toner and a carrier.

Since the internal structures of the four developing chambers are exactly the same, the internal structure will be described below by taking the black developing chamber at the developing position in FIG. 3 as an example, and the internal structures of the other developing chambers will be described. As the reference numerals of the members to be used, yellow, magenta,
In the drawing, reference numerals with subscripts of Y, M, and C are shown in the drawings to distinguish each of the cyan developing chambers, and the description is omitted.

In the black developing device at the developing position in the figure, an opening portion facing the photosensitive drum 1 is formed in the developing device casing portion 83, and a part is exposed through the opening portion in the developing chamber. A developing roller 84 is provided. In the developing chamber, a doctor blade 85 that regulates the amount of developer carried by the developing roller 84 and conveyed to the portion facing the photosensitive drum 1, and the developing blade regulated by the doctor blade 85 and pressed into the developing chamber. An upper transport screw 86 for transporting a part of the developer along the central axis direction from the rear to the front, a guide 87 thereof, and a stirring paddle 88 for stirring the developer in the developing chamber are provided. The stirring paddle 88 has a plurality of developer discharge holes 89a over the width direction of the developing roller 84.
Are formed, and a plurality of agitating plate portions 90 radially extending from the peripheral surface of the hollow cylindrical portion 89, and the upper conveying portion is provided in the hollow cylindrical portion 89 along the center axis direction. A lower transport screw 91 that transports the developer in a direction opposite to that of the screw 86 is accommodated. In the developing device casing below the lower conveying screw 91, when a developer is exchanged due to the development deterioration in the developing chamber, an agent exchange used as an outlet for a deteriorated developer or an inlet for an unused developer (toner mixed). An opening 92 is formed. The agent exchange port 92 is covered from the outside by a cap 93 attached with a screw 94. (Hereinafter, margin)

In FIG. 4, the upper and lower conveying screws 8 are
The front end portions of the reference numerals 6, 91 extend to the outside of the front end wall 50 of the developing device unit, and the upper conveying screw 86 is extended to the extending portion.
There is provided a dropping section 96 for dropping the developer conveyed by the above method onto the lower conveying screw 91 by its own weight. Through this drop portion 96, the developer regulated by the doctor blade 85 and conveyed to the front side by the guide 87 and the upper conveyance screw 86 drops onto the lower conveyance screw 91, and the lower conveyance screw 91 develops the developing roller 84. After being conveyed within the effective width of the above, the developer is discharged from the developer discharge port of the hollow cylindrical portion of the stirring paddle into the developing chamber. Thereby, so-called lateral stirring of the developer in the developing chamber is performed. Further, the developer discharged from the developer discharge port of the hollow cylindrical portion 89 of the stirring paddle 88 to the developer pool at the lower portion of the developing chamber is stirred by the stirring plate portion by the rotation of the stirring paddle 88, whereby vertical stirring is performed. Done. Further, the front end portion of the lower transport screw 91 extends further to the front side than the dropping portion 96, and the toner receiving cases 91Y, M, C, 110 are provided corresponding to the developing chambers of the toner container unit 45. It extends inside, specifically below the toner supply roller 97 provided in the case.

In the example of FIG. 3, the front and rear end wall portions that support the developing roller 84Y and the doctor blade 85Y are small end wall portions that can be separated from other front and rear end wall portions, as shown for a yellow developing device, for example. It is configured in 104. As a result, when cleaning the inside of the developing chamber or replacing parts, the developing roller 84Y and the doctor blade 85Y together with the small end wall portion 104.
It is easy to access to the developing room by removing.

Next, the toner container unit 45 will be described with reference to FIG. 2 again. The toner container unit 45 includes a disk-shaped unit face plate 108 and a total of four toner receiving cases 91Y, M, C attached to the front face of the face plate so as to correspond to each developing device in a one-to-one relationship.
110. The unit face plate 108 has a circular through hole (not shown) through which a cylindrical black toner container can pass, which is formed in the central portion thereof, and the toner receiving cases 91Y, M, C, 110 are It is attached by escaping the through hole.

These four toner receiving cases 91
Of the Y, M, C, and 110, the three color toner receiving cases 91Y, M, and C corresponding to each color developing device are
A toner receiving port is formed facing upward when the corresponding developing chamber is located at the developing position. Then, in the mounting portion around the toner receiving port, color toner containing containers 42, 43, 4 having the same shape for each color containing the color toner are formed.
4 is mounted by sliding in the direction of the rotation axis of the revolver developing unit, with the toner discharge port facing downward.

On the other hand, the black toner receiving case 110 corresponding to the black developing device is the color toner receiving case 91.
The peripheral wall shape is substantially the same as the entire peripheral wall shape of the color toner containers 42, 43, and 44 attached to Y, M, and C. Then, a toner receiving opening having a shape corresponding to the toner discharge opening of the black toner container 41 is formed at a portion of the peripheral wall portion having a shape similar to that of the color toner receiving case and facing the center line of the revolver developing unit.

The black toner container 41 has a cylindrical shape, a toner discharge port is formed on a peripheral wall portion at one end in the longitudinal direction, and a ridge portion for feeding toner is formed on the inner peripheral surface portion from the other end portion. It is formed in a spiral shape toward the toner discharge port side. With this spiral protrusion, the stored toner is sent from the rear end portion to the front end portion during the rotation integrally with the revolver developing unit attached to the revolver developing unit, and the black toner is received from the toner discharge port. The toner is supplied into the toner receiving port of the case. Such a black toner container 41 has a rear end partway inside the hollow cylindrical part 82 of the developing device unit 40 through the center part of the toner container insertion notch 47a formed in the cover 47. The toner container unit 45
Each of the cases is attached in a state of being inserted until it is substantially flush with the front surface of the front end wall portion.

FIG. 4 shows a case 11 for receiving black toner.
0 as an example, inside each of the four toner receiving cases 91Y, M, C, 110,
A toner replenishing roller 97 is provided. The toner replenishing roller 97 is provided in the case when the corresponding developing chamber is located at the developing position.
1 is pivotally supported by the front end wall portion of the case and the unit face plate 108 so as to be located almost directly above the extending portion. The shaft end portion of the toner replenishing roller 97 pivotally supported by the unit face plate 108 penetrates the face plate 108 and the developing unit 40.
The gear 197 is fixedly provided at the protruding end. A supply input gear for drive input (not shown) that meshes with the gear 197 is rotatably provided on the surface of the unit face plate 108 on the developing unit side. Among the replenishment input gears provided for each toner replenishment roller 97, the one corresponding to the toner replenishment roller 97 in the case corresponding to the developing device at the developing position is the gear driven by the above-mentioned replenishment motor 61. The motor 61 can be rotationally driven by engaging with (see FIG. 2). The toner dropped onto the lower carrying screw 91 by the rotation of the toner supply roller 97 is taken into the developer dropped from the upper carrying screw 86 on the way, and is mixed with each other and carried into the developing chamber by the lower carrying screw 91. , Increase the toner concentration of the developer in the developing chamber.
The toner supply control is performed by the rotation control of the toner supply roller 97.

By the way, in the rotary type developing device employed in this embodiment, the developer floating in the developing device is partially exposed, for example, from the opening of the developing device case due to use over time, and the photosensitive drum is exposed. In the area opposite to 1, the developer is conveyed in a predetermined direction and adheres or accumulates on the wall of the developing device above the developing roller 84 that supplies the developer to the photosensitive drum 1. Then, this developer is applied to the developing unit 4
In some cases, the impact or vibration generated by the rotation of 0 causes the toner to drop as a lump on the developer supply member, and is discharged to the outside of the developing device due to the centrifugal force due to the rotation of the developing device unit. . Further, the magnetic developer may be discharged to the outside of the developing device from the portion of the developing roller 84 where the magnetic force is weak through the developing device case opening due to an impact or vibration generated when the developing device unit 40 rotates. In particular, in this embodiment, the transfer material for transferring the developed image on the photosensitive drum 1 or the transfer paper 10 on which the developed image is transferred is used as the developing unit 40.
Since the conveyor belt 15 is provided so as to convey the toner below the developing device, the developer lumps discharged to the outside of the developing device are not conveyed by the conveyor belt 1.
When the developer lumps drop toward No. 5, and the developer lumps adhere to the transfer material, a developer deficient image is generated. Further, in the present embodiment, since images are formed by using developers of different colors, when a developer of a color different from the color of the image formed on the transfer material falls and adheres to the transfer material, This leads to the generation of mixed color images.

FIG. 5 is an explanatory view showing a structure for preventing the scattering of the developer to the outside of the developing device. In the illustrated example, the toner receiving member 330, which is a rigid developer receiving member, covers the outer periphery of the developing device unit 40 below the opening of the developing device of the rotary developing device 4 with respect to the accommodation table 46. It is fixed with a fixing screw 360 so as to be detachable. By providing the toner receiving member 330, even if the toner drops from the developing device opening portion onto the conveyor belt 15, the toner is provided on the accommodation table 46 before the toner reaches the conveyor belt 15. Since the toner is received by the received toner receiving member 330, it does not reach on the transfer paper 10 conveyed below the opening of the developing device, and it is possible to prevent the transfer paper 10 from being contaminated by the falling toner.

Further, the rotary developing device 4 of the present embodiment is constructed such that the accommodating base 46 can be detached from the printer body, and the drum support 35 supporting the photosensitive drum 1 is provided.
0 and the toner receiving member 330 have a slight gap, so a sponge seal 340 as a sealing member that closes the gap is provided on the toner receiving member 330 side in the entire longitudinal direction. And this sponge seal 3
40, the drum support 350 and the toner receiving member 330.
It is also possible to prevent the toner falling from the opening of the developing device from falling on the transfer paper 10 through this gap by closing the gap between the above.

The side cover 59 described with reference to FIG.
The side cover 59 is disposed on the outer periphery of the developing device unit 40. The side cover 59 receives the toner scattered from the developing device case opening of the developing device to the outside of the developing device by the centrifugal force when the developing device unit 40 rotates, The toner receiving member 330 located at the position. A magnet sheet 370 is attached to the surface of the side cover 59 facing the developing device unit 40, and the magnetic force of the magnet sheet 370 allows the side cover 59 to catch the carrier component scattered from the developing device. You can Therefore, for example, it is possible to prevent contamination of the inside of the image forming apparatus due to the scattered carriers adhering to the inside of the image forming apparatus, and generation of abnormal noise due to attachment to the drive system such as gears.

Further, since the toner receiving member 330 is made of a rigid body, the accommodating table 46 is provided in the developing unit 40.
Therefore, the developing gap between the developing roller 84 and the photosensitive drum 1 can be maintained accurately without being twisted by its own weight or the face plate being bent.

Next, the replacement of the developer in the developing device will be described. In the replacement of the developer in this embodiment, in order to efficiently discharge the deteriorated developer from the replacement port 92, the revolver developing device unit 40 together with the accommodating base 46 is pulled out from the printer main body, that is, in FIG. Do as shown. First, in order to remove the lid that closes the exchange port 92 without spilling the developer, the accommodating base 46 (see FIG. 2) of the developing device unit 40 is moved to the developer replacing target as shown in FIG. Fall down so that the exchange port 92 faces upward. Then, at this overturned position, the screw 94 is removed to remove the lid 93 that closes the exchange port 92, and the joint hole (not shown) of the jogo shown by reference numeral 200 is screwed using the screw hole for the screw 94. Thus, as shown in the drawing, the jogo 200 is attached to the developing device. Then, the accommodation table 46 is turned over again to return to the state shown in FIG. 8, and at the first rotation position, the jogo 200 and the recovery container denoted by reference numeral 210 are slid and joined to each other.

Next, the fixing screw 360 for fixing the toner receiving member 330 to the receiving table 46 is removed, and the toner receiving member 330 is removed from the receiving table 46. After this joining, the roller 66 is released and the developing unit 4
0 is rotated clockwise so as to reach the second rotation position where the exchange port 92 of the developing device faces directly below, that is, the developer recovery position shown in FIG. At this time, the collection container 2
Reference numeral 10 is also used as a rotation stop member for stopping the rotation of the developing device unit 40. That is, the recovery container 210 moves in the rotational direction of the developing device unit 40 as the developing device unit 40 rotates. And the exchange port 9 of the developing device
When 2 comes to a position directly below, the recovery container 210
As shown in FIG. 9, a part 210P of the housing 4
The developing unit 40 is stopped by making contact with a part 46P of the developing unit 6. Thereby, the developing unit 40
Rotation stops at the developer collecting position where the rotation is good.
Then, the developer is collected from the developing device at the developer collecting position having the best collecting property.

Here, in order that the recovery container 210 can take the position shown in FIG. 9, the side cover 59 in FIG. 2 is formed with a cutout portion 59a formed by cutting out a hatched portion in the drawing. There is. Further, the toner receiving member 330 is attached so as to cover the lower portion of the side surface cover 59 so that the toner does not drop from the cutout portion 59a onto the lower transfer paper 10 during the normal developing operation. The toner receiving member 330 is fixed to the accommodation table 46 by a fixing screw 360. When the developer replacement work is performed, the fixing screw 360 is removed to remove the toner receiving member 33.
By removing 0 from the accommodation table 46, the recovery container 210 can be set to the position shown in FIG.
By doing so, during the developing operation,
By the toner receiving member 330, it is possible to prevent the toner from dropping onto the transfer paper 10, and at the time of the developer replacement work, the toner dropped on the toner receiving member 330 can be cleaned, and the toner is most collected from the developing device. The developer can be collected at the developer collecting position having good properties.

Then, at this developer collecting position, the developer inside the developing device is collected into the collecting container 210 through the jogo 200 as shown by an arrow 202 in FIG. This recovery is performed by causing the developer in the developing device to flow down by its own weight through the exchange port 92 (see the arrow indicated by 202 in the figure).

Further, at the time of this recovery, in order to separate the developer held by the magnetic force on the developing sleeve from the developing sleeve and let it flow down by its own weight, the developing input gear is rotated by using a jig or a hand. , The developing roller 84, the vertical transport screws 86 and 91, and the paddle 88 are rotated.

In the illustrated example, the movement of the developer from the actual developing device to the recovery container 210 is performed during the rotational movement from the developer input position shown in FIG. 7 to the developer recovery position shown in FIG. It has begun.

After the recovery of the developer into the recovery container 210 is completed, the developing device unit 40 is rotated counterclockwise and returned to the first rotation position shown in FIG. The recovery container 210 is slid from the jogo 200 and removed.

Thereafter, as shown in FIG. 7, the accommodating table 46 is turned over so that the exchange port 92 of the developing device faces upward, and a new developer is attached to the jogo 200 as indicated by an arrow 203 in the figure. It is charged into the developing device through. Even when this new developer is charged, the developer can be uniformly dispersed by rotating the developing roller 84, the vertical transport screws 86 and 91, and the stirring paddle 88. After the introduction of the developer is completed, the jogo 200 is removed from the exchange port 92, and the exchange port 92 is closed with the lid 93.
Then, the accommodation table 46 is pushed into the printer body and set at a predetermined position. As a result, the developer replacement work is completed.

[0052]

According to the invention of claim 1, the developer discharged from the developing area where the developer supplying member and the latent image carrier face each other is located below the developing area below the developing unit. Even if the developer drops toward the transport path of the transfer material transport device located, the developer is received by the developer receiving member before reaching the transport path, so the dropped developer falls onto the transport path. Then, the transfer material that transfers the developed image of the latent image carrier when it is transported through the transport path is contaminated, or the toner image is generated by adhering to the transfer material onto which the developed image is transferred. It has an excellent effect of preventing this. Further, for example, when each of the developing devices contains a developer of a different color, the developer of a color different from the color of the image formed on the transfer material drops and adheres to the transfer material. By doing so, it is possible to prevent the occurrence of a mixed color image.

In particular, according to the second aspect of the invention, the gap between the developer receiving member and the image forming apparatus main body side member which is close to the developer receiving member from the latent image carrier side is sealed by the seal member. By doing so, it is possible to reliably prevent the transfer material from being contaminated due to a part of the developer that has dropped below the developing area falling on the transfer material through the gap.

In particular, according to the third aspect of the invention, the developer receiving member exerts a function of increasing the strength in the longitudinal direction of the developing device unit supporting member, so that the developing device unit supporting member is Since twisting or bending due to the weight of the developing device unit does not occur, unlike the case where twisting or bending of the developing device unit support occurs,
It is possible to always obtain a good image without changing the developing gap between the developer supply member and the latent image carrier.

In particular, according to the invention of claim 4, during the developing operation, by using the apparatus with the developer receiving member mounted, the developer is transferred onto the transfer material by the developer receiving member. It can be prevented from falling. Also,
At the time of developer replacement work, by removing the developer receiving member, the toner accumulated in the developer receiving member can be easily cleaned, and moreover, from the developing device,
The developer can be collected at the developer collecting position having the best collecting property.

According to the invention of claim 5, the guide member arranged on the outer periphery of the developing device unit receives the developer scattered to the outside of the developing device and collects it under the guide member by its own weight. Since it is guided to, the inside of the image forming apparatus can be prevented from being contaminated by the scattered developer. If the guide member is configured to be detachable, the developer received by the guide member is collected in the lower part, so that the collectability of the collected developer can be improved.

In particular, according to the invention of claim 6, since the developer scattered outside the developing device is attracted to the guide member side by the magnetic force of the magnet used for the guide member, no magnet is used. Compared with the case, the scattered developer can be efficiently attracted to the guide member side. In addition, since the magnetic developer once housed in the guide member is securely held in the guide member by the magnetic force of the magnet, even when it receives vibration from the outside, for example, outside the guide member. There is no scattering. Therefore, it is possible to more reliably prevent the inside of the image forming apparatus from being contaminated by the scattered magnetic developer.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a copying machine according to the present embodiment.

FIG. 2 is an exploded perspective view of a rotary developing device of the copying machine.

FIG. 3 is a sectional view of a developing unit of the developing device.

FIG. 4 is an explanatory view of a connection structure between a developing device and a toner container in the developing device.

FIG. 5 is an explanatory view showing a mounting state of a toner receiving member for preventing the developer from falling onto the transfer paper.

FIG. 6 is an explanatory diagram of developer replacement work in the developing device according to the present embodiment.

FIG. 7 is an explanatory view of the same developer replacement work.

FIG. 8 is an explanatory diagram of the same developer replacement work.

FIG. 9 is an explanatory diagram of the same developer replacement work.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoconductor drum 4 Rotational developing device 40 Developing device unit 41 Black toner container 59 Side cover 83, 83C, 83M, 83Y Developing device casing part 84 Developing roller 200 Joego 210 Recovery container 330 Toner receiving member 340 Sponge seal 350 Drum support Body 360 Fixing screw 370 Magnet sheet

Claims (6)

[Claims] 1. A latent image bearing member on which a latent image is formed and a developing device unit having a plurality of developing devices arranged around a rotation center line are rotated about the rotation center line to carry the latent image bearing member. A rotary developing device for developing each latent image on the latent image carrier by moving each developing device to a developing position facing the body, and a transfer material or the developed image for transferring the developed image on the latent image carrier. An image forming apparatus including a transfer material conveying device that conveys the transferred transfer material below the developing device unit, in order to supply a developer to the latent image carrier of the developing device at the developing position. The developer supply member partially exposed from the container case opening falls from the area facing the latent image carrier toward the transfer path of the transfer material transfer device located below the developer unit. Providing a developer receiving member for receiving the developer An image forming apparatus comprising. 2. The image forming apparatus according to claim 1, wherein the developer receiving member is formed separately from a member of the image forming apparatus main body, and an image is provided close to the developer receiving member from the latent image carrier side. An image forming apparatus comprising a seal member for sealing a gap between a member of the main body of the forming apparatus and the developer receiving member. 3. The image forming apparatus according to claim 1, further comprising a developing unit support for supporting the developing unit in the main body of the image forming apparatus to increase the strength of the developing unit support in the longitudinal direction. An image forming apparatus, wherein the developer receiving member is provided on the developing device unit support. 4. The image forming apparatus according to claim 1, further comprising a developing device unit support member that rotatably supports the developing device unit, wherein the developing device unit support member is in a predetermined first rotation position on the developing device unit support member. A developer recovery container is attached to the opening for accommodating developer contained in the developing device, and the developing device having the developer recovery container is rotated to a predetermined second rotation position on the developing device unit support, A path configured such that the developer can be collected in the developer collecting container through the opening, and the developer collecting container moves during the rotation of the developing unit from the first rotation position to the second rotation position. An image forming apparatus, wherein the developer receiving member is detachably attached to a position overlapping with the. 5. A latent image bearing member on which a latent image is formed, and a developing device unit having a plurality of developing devices arranged around a rotation center line are rotated about the rotation center line to carry the latent image bearing member. In an image forming apparatus equipped with a rotary developing device for developing each latent image on the latent image carrier by moving each developing device to a developing position facing the body, centrifugal force generated when the developing device unit rotates An image forming apparatus characterized in that a guide member for guiding the developer scattered to the outside of the developing device through the opening of the developing device case of the developing device and collecting the developer in the lower part is arranged on the outer periphery of the developing device unit. 6. The image forming apparatus according to claim 5, wherein a magnetic developer is used as the developer, wherein at least a part of the guide member is formed by using a magnet.