JP2000035736A - Toner recovery device for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a toner carrying path short and to prevent a decrease in the lifespan of a cleaning blade. SOLUTION: In the toner recovery device, the cleaning blade 12 of a cleaner is disposed on a photoreceptor drum 2, and a toner recovery hopper 6, disposed on a developing device 8, is provided for storing residual toner removed from the peripheral surface of the photoreceptor drum by the cleaning blade. The toner recovery hopper has a bottom wall 61 forming a toner collecting part 611 having a toner falling port 613 connected to the development housing 80 of the developing device. The bottom wall is so formed as to slope down toward the toner collecting part, thereby guiding the residual toner, removed by the cleaning blade, to the toner collecting part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner collecting device for an image forming machine such as an electrostatic copying machine, a printer, a facsimile and the like.

[0002]

2. Description of the Related Art An image forming machine of this type develops a toner image by applying a toner to a photosensitive drum rotatably disposed and an electrostatic latent image formed on a peripheral surface of the photosensitive drum. And a cleaning device for removing residual toner adhered to the peripheral surface of the photosensitive drum. The residual toner removed from the peripheral surface of the photosensitive drum by the cleaning device is collected and returned to the developing device,
2. Description of the Related Art Image forming machines that are reused as a developer have been put to practical use. As a method of collecting the residual toner, the residual toner removed from the peripheral surface of the photosensitive drum by the cleaning device is once conveyed to the front side or the back side of the photosensitive drum, and new toner is supplied into the developing housing of the developing device. In general, the sheet is conveyed to a hopper. Further, there is also used a method in which the residual toner removed from the peripheral surface of the photoconductor drum by the cleaning blade is released on the peripheral surface of the photoconductor drum by releasing the cleaning blade, moved to the developing device, and collected.

[0003]

In the former method of collecting the residual toner described above, the toner conveying path is long and the whole apparatus is complicated, and the toner adheres to the toner conveying path and solidifies, so that the toner conveying member is locked. There are problems such as. Further, the latter method of recovering the residual toner requires a mechanism for releasing the cleaning blade, and the cleaning blade repeatedly presses and releases, so that there is a problem that so-called curling occurs and the life is short. Further, there is a concern that the toner may be scattered in the feeling of the cleaning device and the developing device to stain the inside of the device.

[0004] The present invention has been made in view of the above-mentioned facts, and its main technical problem is that the toner transport path is short,
Further, it is an object of the present invention to provide a toner collecting device of an image forming machine which can shorten the life of a cleaning blade and prevent toner from scattering into the machine.

[0005]

According to the present invention, there is provided, in accordance with the present invention, a photosensitive drum rotatably disposed and a static drum formed on a peripheral surface of the photosensitive drum. An image forming machine comprising: a developing device that applies toner to an electrostatic latent image to develop a toner image; and a cleaning device that removes residual toner attached to the peripheral surface of the photosensitive drum. A blade disposed above the photoconductor drum, a toner recovery hopper disposed above the developing device and containing residual toner removed from a peripheral surface of the photoconductor drum by the cleaning blade; Hopper is
A bottom wall forming a toner collecting portion having a toner dropping port connected to a developing housing of the developing device, wherein the bottom wall is formed to be inclined downward toward the toner collecting portion, and is formed by the cleaning blade. A toner collection device for an image forming apparatus, wherein the removed residual toner is guided to the toner collecting section.

The toner drop openings are provided at both ends in the width direction of the bottom wall, respectively, and the bottom wall is provided with residual toner removed by a cleaning blade toward the toner drop openings provided at both ends in the width direction. Is formed so as to be guided.

Further, a toner conveying member for conveying the toner toward the toner drop port is provided in the toner collecting section. The toner falling ports are provided at both ends in the width direction of the bottom wall, respectively, and the toner conveying member conveys the toner in the toner collecting section from the center to both ends.

According to the present invention, other features of the present invention will be clarified by the following description.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of a toner collecting device for an image forming machine constituted according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of a main part of a printer as an image forming machine equipped with a process unit having an embodiment of a toner collecting device constructed according to the present invention, and FIG. 2 is a cross-sectional view along AA in FIG. FIG. 3 is an exploded perspective view showing the process unit shown in FIG. The printer in the illustrated embodiment includes a process unit 1. The process unit 1 includes a photosensitive drum 2, a unit housing 4, a toner collecting hopper 6, and a developing device 8.

The unit housing 4 includes an upper wall 41, a front wall 42 formed obliquely downward from a front end (left end in FIG. 1) of the upper wall 41, and a width direction of the upper wall 41 (in FIG. 1). Side walls 43 and 44 extending downward from both ends (in the direction perpendicular to the plane of the paper, the vertical direction in FIG. 2),
These are integrally formed of an appropriate synthetic resin.
A sealing member 420 made of a synthetic resin film is attached to a front end of the front wall 42 by a fixing means such as a double-sided adhesive tape or an adhesive. The tip of the seal member 420 is brought into contact with the peripheral surface of the photosensitive drum 2.
First support holes 431 and 441 are provided at the front ends (upper left in FIG. 3) of the side walls 43 and 44, respectively. The rotation shafts of the photosensitive drum 2 are provided in the first support holes 431 and 441, respectively. 20 is rotatably supported. The photosensitive drum 2 rotatably supported in this way
Is rotated in a direction indicated by an arrow in FIG. 1 by a driving unit (not shown), and a charging area 21 and an electrostatic latent image forming area 2
2, development area 23, transfer area 24 and cleaning area 25
Are sequentially moved. Also, the side walls 43 and 44
The second support holes 432 and 442 are also provided at the rear end (the lower right in FIG. 3). The support shaft 14 is inserted into the second support holes 432 and 442 as described later.

The toner recovery hopper 6 has a bottom wall 61.
A rear wall 62 extending upward from a rear end (right end in FIG. 1) of the bottom wall 61; and a rear wall 62 extending upward from both ends in the width direction of the bottom wall 61 (a direction perpendicular to the plane of FIG. 1 and a vertical direction in FIG. 2). It has extending side walls 63 and 64, which are integrally formed of a suitable synthetic resin. Bottom wall 61
At the front end (the left end in FIGS. 1 and 2) of the
10 is provided, and a mounting plate 7
Are attached by fixing means such as an adhesive. A charging corona discharger 10 is mounted on the lower surface of the mounting plate 7 so as to face the peripheral surface of the photosensitive drum 2. A cleaning blade 12 is mounted on the upper surface of the mounting plate 7 by a fixing means such as an adhesive.
In the illustrated embodiment, the cleaning blade 12 is formed of an elastic member such as urethane rubber, and its tip is formed on the peripheral surface of the photosensitive drum 2 in a cleaning area 25 defined above the photosensitive drum 2. The residual toner adhered to the peripheral surface of the photosensitive drum 2 by being pressed is removed. In the illustrated embodiment, toner collecting portions 611 and 612 are formed on both sides of the rear end (the right end in FIGS. 1 and 2) of the bottom wall 61. And
On both sides of the rear end of the bottom wall 61, toner collecting portions 61 are respectively provided.
1, toner drop ports 613 and 614 opening to 612 are provided. Further, a toner drop port 61 is provided on the bottom wall 61.
Connection flanges 615 and 616 are formed to protrude downward from the periphery of the third and third 614, respectively. The bottom wall 61 is formed so as to be inclined so as to guide the residual toner removed from the peripheral surface of the photosensitive drum 2 by the cleaning blade 12 toward the toner drop ports 613 and 614. In the illustrated embodiment, the central portion of the bottom wall 61 is formed in a mountain shape so that the residual toner flows toward the toner drop ports 613 and 614. Engaging portions 631 and 641 are formed on the side walls 63 and 64, respectively (see FIG. 3). Blind hole 632,
642 are provided. The toner recovery hopper 6 configured as described above is fixed to the unit housing 4 by fixing means such as welding or an adhesive, and is integrated with the unit housing 4.

Next, the developing device 8 will be described.
The illustrated developing device 8 includes a developing housing 80 in which a developer composed of one-component toner is stored. Developing housing 80 that can be molded from an appropriate synthetic resin
Are the bottom wall 81, the side walls 82 and 83, and the developing housing 8
0 includes a cover wall 84 covering the upper side. The bottom wall 81 of the developing housing 80 is provided with four transport paths 811, 812, 813, and 814 formed in a concave arc shape and extending in the width direction (perpendicular to the plane of FIG. 1).

The dimensions between the outer surfaces of the side walls 82 and 83 are set to values slightly smaller than the dimensions between the inner surfaces of the side walls 43 and 44 of the unit housing 4. Are disposed between the side walls 43 and 44.
Support holes 821 and 831 corresponding to the second support holes 432 and 442 provided at the rear ends of the side walls 43 and 44 of the unit housing 4 are provided at the upper ends of the side walls 82 and 83 at positions facing each other. Have been. Unit housing 4
Support holes 432 and 4 provided in side walls 43 and 44 of
By inserting the support shaft 14 through the support holes 821 and 831 provided in the side walls 82 and 83 of the developing housing 80 and the developing housing 80, the unit housing 4 and the developing housing 80
They are rotatably connected to each other around four turns. Also, the side wall 8
Lock holes 822 and 832 are formed at the upper end portions of the support holes 2 and 83 at positions on the front side (upper left side in FIG. 3) of the support holes 821 and 831, respectively. This locking hole 822,
Both ends of the coil springs 16 and 16 are respectively locked in locking holes 832 and locking holes 632 and 642 formed in the side walls 63 and 64 of the toner recovery hopper 6. Therefore, the developing housing 80 is urged to rotate clockwise in FIG. 1 around the support shaft 14 with respect to the unit housing 4 integrally formed with the toner collecting hopper 6 by the spring force of the coil springs 16, 16. Have been.

The cover wall 84 is attached to the rear end of the bottom wall 81 and the upper surfaces of the side walls 82 and 83 by fixing means such as welding. On both sides of the cover wall 84 in the width direction (the direction perpendicular to the sheet of FIG. 1), the transport path 813 is provided.
And 814 are provided with toner receiving openings 841 and 842, respectively, at positions facing the boundary between them. The distance between the toner receiving openings 841 and 842 is set to a value corresponding to the distance between the toner drop ports 613 and 614 provided on the bottom wall 61 of the toner recovery hopper 6. A connection flange 84 is formed on the upper surface of the cover wall 84 so as to protrude upward from the periphery of the toner receiving openings 841 and 842.
3 and 844 are provided. The connection flanges 843 and 844 and the bottom wall 6 of the toner recovery hopper 6
Both ends of the flexible joints 18, 18 are fitted to the connection flanges 615, 616 provided in 1, respectively, and both connection flanges are connected.

The developing housing 8 constructed as described above
0, transport paths 811, 81 formed in the bottom wall 81.
A developing roller 85, a supply roller 86, a downstream stirring means 87, and an upstream stirring means 88 are provided at 2, 813 and 814, respectively. The developing roller 85 is used for the developing housing 8.
The rotary shaft 851 is rotatably mounted on the side walls 82 and 83 constituting the above-described 0, and a solid synthetic rubber roller 852 fixed to the outer peripheral surface of the rotary shaft 851. The rotating shaft 851 can be formed from an appropriate metal material such as stainless steel. The solid synthetic rubber roller 852 is made of a relatively flexible and conductive material, for example, a conductive solid synthetic rubber such as urethane rubber. The roller 852 of the developing roller 85 configured as described above is exposed through an opening formed in the developing housing 80 and is positioned to face the photosensitive drum 2. The peripheral surface of the roller 852 constituting the developing roller 85 is formed by the springs of the coil springs 16 and 16 stretched between the side walls 63 and 64 of the toner collecting hopper 6 and the side walls 82 and 83 of the developing housing 80, respectively. Due to the force, the peripheral surface of the photosensitive drum 2 is pressed against the peripheral surface of the photosensitive drum 2 in the developing area 23, and the peripheral surface of the roller 852 is slightly elastically compressed at the pressed nip portion. The rotating shaft 851 of the developing roller 85 is rotationally driven in a direction indicated by an arrow by a driving unit (not shown), and a developer holding region 853, a developer regulating region 854, and the developing region 23 are formed.
Are sequentially moved. The developer regulation area 854
5, the regulating blade 32 of the developer regulating means 30 is pressed against the peripheral surface of the developing roller 85. The regulating blade 32 is attached to the front end (the left end in FIG. 1) of the cover wall 84 via the attachment member 33.

The replenishing roller 86 is connected to the developing housing 8.
The developing roller 85 includes a rotating shaft 861 rotatably mounted on the side walls 82 and 83 constituting the rotating shaft 86 and a roller 862 fixed to the outer peripheral surface of the rotating shaft 861.
And are arranged in parallel. The rotating shaft 861 can be formed of an appropriate metal material such as stainless steel, similarly to the rotating shaft 851 of the developing roller 85. The roller 862 is made of foam such as foamed silicone or foamed urethane. The roller 862 is pressed against the roller 852 of the developing roller 85 in a developer holding area 853 which is a nip portion with the developing roller 85. The hardness of the foam forming the roller 862 of the replenishing roller 86 is set to be considerably smaller than the hardness of the roller 852 forming the developing roller 85, and by pressing the roller 862 against the roller 852 of the developing roller 85. It is desirable that the roller 862 be elastically compressed by about 0.1 to 0.6 mm in the nip area. Rotary shaft 86 of supply roller 86
1 is driven to rotate in a direction indicated by an arrow by a driving means (not shown), that is, in a developer holding area 853 which is a nip portion between the roller 862 and the roller 852 of the developing roller 85, in the opposite direction.

The downstream agitating means 87 is disposed in parallel with the replenishing roller 86, and includes a rotating shaft 871 rotatably mounted on the side walls 82 and 83 constituting the developing housing 80; The agitation member 872 fixed to the agitator 871 and an agitation sheet member 873 having elasticity attached to the agitation member 872 are included. Stirring member 872
Is formed of a synthetic resin and has a longitudinal direction (FIG. 1).
In the direction perpendicular to the plane of the drawing). The stirring sheet member 873 is formed of, for example, polyethylene terephthalate (PET) resin having flexibility and elasticity, and is fixed to an end edge of the stirring member 872 with an adhesive or the like. In the stirring means 87 thus configured, the rotating shaft 871 is continuously driven to rotate in a direction indicated by an arrow in FIG. 1 by a driving means (not shown).

The upstream stirring means 88 is constructed similarly to the downstream stirring means 87. That is, the upstream stirring means 88 is provided with the side wall 8 constituting the developing housing 80.
A rotating shaft 881 rotatably mounted on the rotating shafts 2 and 83; a stirring member 882 fixed to the rotating shaft 881 and provided with a plurality of openings 882a in the longitudinal direction; and an elastic stirring mounted on the stirring member 882. The sheet includes a sheet member 883, and the rotating shaft 881 is continuously driven to rotate in a direction indicated by an arrow in FIG.

The process unit configured as described above is mounted at a predetermined position on a machine frame (not shown).
As shown in FIG. 1, a printer as an image forming machine equipped with a process unit includes a laser unit 34 disposed on the right side of the process unit in FIG.
The laser unit 34 irradiates a laser beam 340 corresponding to print data from, for example, a word processor connected to a printer to the peripheral surface of the photosensitive drum 2 in the electrostatic latent image forming area 22, and An electrostatic latent image is formed on the surface. At this time, the laser light 340 from the laser unit 34 is formed so as to protrude downward from the periphery of the toner drop ports 613 and 614 provided in the bottom wall 61 of the toner recovery hopper 6 as shown in FIGS. Between the connection flanges 615 and 616, the bottom wall 61 of the toner recovery hopper 6 and the cover wall 84 of the developing housing 80.
To the peripheral surface of the photosensitive drum 2.
In the illustrated embodiment, the printer includes a transfer roller 36 disposed opposite to the peripheral surface of the photosensitive drum 2 in the transfer area 24 and a registration roller pair 38 disposed below the transfer area 24. Have.

A printer provided with an embodiment of the toner collecting device constituted according to the present invention is constituted as described above, and its operation will be described below. Each of the above members starts operating based on a print command from a word processor (not shown) or the like, and the peripheral surface of the photosensitive drum 2 is substantially uniformly charged to a specific polarity by the charging corona discharger 10. Next, a laser beam 340 corresponding to print data from a word processor or the like is irradiated from the laser unit 34 onto the charged peripheral surface of the photosensitive drum 2 to form an electrostatic latent image. The electrostatic latent image thus formed on the peripheral surface of the photosensitive drum 2 is developed into a toner image by the developing operation of the developing device 8. This developing action is performed as follows. When the operation of the developing device 8 is started, the developing roller 85, the replenishing roller 86, the downstream agitating means 87 and the upstream agitating means 88 are driven to rotate in directions indicated by arrows by driving means (not shown). The stirring member 882 and the stirring sheet member 8 constituting the upstream stirring means 88
83 rotates in the direction indicated by the arrow, and
The developer accommodated in 14 is sent to the transport path 813 while being stirred. Further, when the stirring member 872 and the stirring sheet member 873 constituting the downstream stirring means 87 rotate in the direction shown by the arrow, the developer contained in the conveyance path 813 is sent to the conveyance path 812 while being stirred, It is supplied to the supply roller 86 from above. In this way, the developer supplied by the downstream stirring means 87 rides on the roller 862 of the supply roller 86 and is transported to the nip portion which is the developer holding area 853 with the roller 852 of the developing roller 85. In this manner, the developer conveyed to the developer holding area 853, which is the nip between the supply roller 86 and the developing roller 85,
The developer is held on the peripheral surface of the roller 852 constituting the developing roller 85 and is conveyed toward the developer regulating area 854.

In the developer regulating area 854, the regulating blade 32 constituting the developer regulating means 30 is
5 acts on the developer retained on the peripheral surface of the roller 852 to regulate the developer retained on the peripheral surface of the roller 852 to a required amount to form a thin layer.

As described above, the developer is held on the peripheral surface of the roller 852 constituting the developing roller 85 in the developer holding area 853, and is formed into a thin layer by the action of the regulating blade 32 of the developer regulating means 30 in the developer regulating area 854. The formed developer is moved in the developing zone 23 with the rotation in the direction of the arrow.
Transported to In the developing area 32, the photosensitive drum 2
The developer is applied to the electrostatic latent image on the electrostatic photosensitive member disposed on the peripheral surface of the toner image, and the electrostatic latent image is developed into a toner image. For example, an electrostatic latent image has a non-image area charged to about +600 V and an image area charged to about +120 V, and toner as a developer is attached to the image area (so-called reversal development).

On the other hand, the printer is provided with transfer paper supply means (not shown), and the transfer paper is conveyed one by one toward the registration roller pair 38 by the transfer paper supply means. The transfer paper conveyed toward the pair of registration rollers 38 stops at the nip portion of the pair of registration rollers 38, and is transferred by the pair of registration rollers 38 which are operated in synchronization with the rotation of the photosensitive drum 2. 2
4 is conveyed. Then, the transfer paper is transported between the photosensitive drum 2 and the transfer roller 36 in the transfer area 24, and the toner image formed on the peripheral surface of the photosensitive drum 2 is transferred to the surface thereof. The transfer paper on which the toner image has been transferred is
The toner image is conveyed to a fixing unit (not shown), where it is discharged after being heat-fixed.

As described above, the toner image formed on the peripheral surface of the photosensitive drum 2 in the transfer area 24 is transferred to the transfer paper, and the toner remaining on the peripheral surface of the photosensitive drum 2 at this time is removed from the cleaning area 25. Is removed by the cleaning blade 12. The residual toner removed from the peripheral surface of the photosensitive drum 2 accumulates on the cleaning blade 12 and the mounting plate 7. When the accumulated amount exceeds a predetermined amount, it is sent to the upper surface of the bottom wall 61 of the toner recovery hopper 6. . The residual toner sent to the upper surface of the bottom wall 61 is
1 is formed to be inclined so as to be guided toward the toner drop openings 613 and 614, so that the toner drop
3 and 614, and are dropped from the toner drop ports 613 and 614. The residual toner dropped from the toner drop ports 613 and 614 is
15, 616, the flexible joints 18, 18 and the cover wall 84 of the developing housing 80 are carried into the developing housing 80 from the toner receiving openings 841, 842 provided in the cover wall 84 through the connection flanges 843, 844 provided. . The residual toner conveyed into the developing housing 80 is stirred and mixed with the new toner existing in the developing housing 80 by the upstream stirring means 88 and the downstream stirring means 87, and is subjected to a developing action.

As described above, the toner collecting device of the image forming machine in the embodiment shown in FIGS. 1 to 3 sends the residual toner removed by the cleaning blade 12 onto the bottom wall 61 of the toner collecting hopper 6, and The wall 61 guides the toner to the toner drop ports 613 and 614 and drops the toner into the developing housing 80 from the toner drop ports 613 and 614. Therefore, the toner transport path is short and the entire apparatus is simplified, and the toner transport path is reduced. The toner does not adhere and harden. Further, the cleaning blade 12 does not need to repeat pressing and releasing each time to collect the residual toner, so that the so-called curling can be prevented and the durability can be improved.

Next, another embodiment of the toner collecting device of the image forming machine constituted according to the present invention will be described with reference to FIGS. The embodiment shown in FIGS. 4 and 5 is one in which the toner collecting device constructed according to the present invention is applied to a developing device using a two-component developer.
The same members as those of the embodiment shown in FIG. 3 to FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. A developing device 8 using a two-component developer composed of toner and carrier particles includes a developer applying unit 91 and a downstream stirring and conveying unit 9 in a developing housing 80.
2 and the upstream stirring and conveying means 93 are provided.

The developer applying means 91 is disposed in parallel with the photosensitive drum in the developing area 23 with a slight gap. The developer applying unit 91 is provided with the sleeve member 9.
11 and a stationary permanent magnet member 912 disposed in the sleeve member 911. Sleeve member 9
Numeral 11 is made of a nonmagnetic material such as aluminum, and is rotatably mounted. The stationary permanent magnet member 912 is fixed at a predetermined position. A rotating shaft (not shown) is fixed to the sleeve member 911. It is rotationally driven in the direction shown by the arrow by a driving means (not shown). In the developer regulating area 854, a cutting board 94 attached to the front end (the left end in FIG. 4) of the cover wall 84 of the developing housing 80 is disposed in parallel with and near the peripheral surface of the sleeve member 911. The ear cutting plate 94 is provided with a sleeve member 911.
Regulates the amount of the developer that is held on the peripheral surface and is conveyed to the developing area 23.

The downstream stirring / conveying means 92 disposed behind the developer applying means 91 comprises a rotating shaft 921 and a spiral blade 922 formed on the rotating shaft 921. Downstream stirring and conveying means 92 configured as described above
The rotating shaft 921 is driven to rotate in a direction indicated by an arrow by a driving unit (not shown), and the developer is transported from the back side to the front side while being stirred and supplied to the developer applying unit 91.

The upstream stirring / conveying means 93 disposed behind the downstream stirring / conveying means 92 also comprises a rotating shaft 931 and a spiral blade 932 formed on the rotating shaft 931. Upstream stirring and conveying means 93 configured as described above
The rotating shaft 931 is driven to rotate in a direction indicated by an arrow by a driving unit (not shown), and the developer is conveyed from the front side to the back side while being stirred, and the downstream stirring conveyance unit 92
Send to the side. The developing device using the two-component developer composed of the toner and the carrier particles does not constitute a novel feature of the present invention, but may have a well-known form itself. The description is omitted in this specification.

In the embodiment shown in FIGS. 4 and 5,
The unit housing 4 and the toner recovery hopper 6 are integrally formed. The unit housing 4 has the upper wall 41 in the embodiment shown in FIGS. 1 to 3 removed except for the front end (left end in FIG. 4). Further, the bottom wall 61 of the toner collecting hopper 6 is formed by a uniform plane in a width direction (a direction perpendicular to the paper surface in FIG. 4 and a vertical direction in FIG. 5). Further, a toner conveying roller 66 is disposed in the toner collecting section 65. This toner transport roller 6
Reference numeral 6 includes a rotating shaft 661 rotatably mounted on the side walls 63 and 64 of the toner collecting hopper 6, and a roller 662 fixed to the outer peripheral surface of the rotating shaft 661. The rotating shaft 661 can be formed of a suitable metal material such as stainless steel, and is driven to rotate in a direction indicated by an arrow in FIG. The roller 662 is made of foam such as silicone foam or urethane foam, and has spiral grooves 662a and 662b formed in the peripheral surface thereof in opposite directions from the center toward both ends. Note that a cover 68 is attached to the upper surface of the toner collection hopper 6.

The embodiment shown in FIGS. 4 and 5 is configured as described above, and the operation of the toner collecting device will be described below. In the same manner as in the embodiment shown in FIGS. 1 to 3, the toner image formed on the peripheral surface of the photosensitive drum 2 in the transfer area 24 is transferred to the transfer paper. The remaining toner is removed by the cleaning blade 12 in the cleaning area 25. The residual toner removed from the peripheral surface of the photosensitive drum 2 is supplied to the cleaning blade 12 and the mounting plate 7.
When the accumulated amount exceeds a predetermined amount, the toner is sent to the upper surface of the bottom wall 61 of the toner collecting hopper 6. The residual toner sent to the upper surface of the bottom wall 61 is transferred to the toner collecting portion 65 by the bottom wall 61.
Since it is formed to be inclined to guide toward,
It is guided toward the toner collecting section 65. On the other hand, when the toner concentration of the developer in the developing housing 80 falls below the lower limit, the toner conveying roller 66 disposed in the toner collecting section 65 receives a signal from a toner concentration detector (not shown) disposed in the developing housing 80. It is operated by control means (not shown) based on the above. When the toner conveying roller 66 is operated, the residual toner guided to the toner collecting section 65 is formed in a spiral groove 662 formed on the peripheral surface of the roller 662.
By the action of a and 662b, the sheet is conveyed from the center toward both ends, and is dropped from the toner drop ports 613 and 614. Residual toner dropped from the toner drop ports 613 and 614 is connected to the connection flanges 615 and 616, the flexible joints 18 and 18, and the connection flange 843 provided on the cover wall 84 of the developing housing 80.
Through 844, the toner is carried into the developing housing 80 through the toner receiving openings 841 and 842 provided in the cover wall 84. The residual toner conveyed into the developing housing 80 is stirred and mixed with the new toner existing in the developing housing 80 by the upstream stirring / conveying means 93 and the downstream stirring / conveying means 92 to be subjected to a developing action. When the toner concentration of the developer in the developing housing 80 increases and becomes equal to or higher than the upper limit, the toner transport roller 66 is stopped by a control unit (not shown).

As described above, the toner collecting device of the image forming machine in the embodiment shown in FIGS. 4 and 5 sends the residual toner removed by the cleaning blade 12 onto the bottom wall 61 of the toner collecting hopper 6, and Guided by the bottom wall 61 to the toner collecting section 65, the toner conveying roller 6
6, the toner is conveyed toward the toner drop ports 613 and 614 and dropped into the developing housing 80 from the toner drop ports 613 and 614.
The same operational effects as those of the embodiment shown in FIGS.

Although the present invention has been described based on an embodiment in which the present invention is applied to a printer, the present invention is not limited to the illustrated embodiment, and can be applied to, for example, an electrostatic copying machine or a facsimile. Various changes or modifications can be made without departing from the technical idea of the present invention.

[0035]

The toner collecting device for an image forming machine according to the present invention is constructed as described above, and has the following functions and effects.

That is, according to the present invention, the toner collecting hopper has a bottom wall forming a toner collecting portion provided with a toner drop port connected to the developing housing of the developing device, and the bottom wall faces the toner collecting portion. Is formed so as to be inclined downward, and the residual toner removed by the cleaning blade is formed so as to be guided to the toner collecting portion, so that the toner transport path for transporting the residual toner is short, and the entire apparatus is simplified. The toner does not adhere to the toner conveying path and harden. Further, since the cleaning blade does not need to repeat pressing and releasing each time to collect the residual toner, it is possible to prevent so-called curling, improve durability, and scatter toner into the machine. Can be prevented. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of an image forming machine equipped with a process unit having an embodiment of a toner recovery device configured according to the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is an exploded perspective view showing the process unit shown in FIG. 1;

FIG. 4 is a cross-sectional view of a main part of an image forming apparatus equipped with a process unit having another embodiment of a toner recovery device configured according to the present invention.

FIG. 5 is a sectional view taken along line BB in FIG. 4;

[Explanation of symbols]

1: process unit 2: photosensitive drum 4: unit housing 41: upper wall of unit housing 42: front wall of unit housing 420: sealing member 43, 44: side wall of unit housing 431, 441: first support hole 432, 442: second support hole 6: toner collection hopper 61: bottom wall of toner collection hopper 611, 612: toner collecting section 613, 614: toner drop port 615, 616: connection flange 62: rear wall 63 of toner collection hopper 64: Side wall of toner recovery hopper 631, 641: Engaging portion 632, 642: Locking hole 65: Toner collecting portion 66: Toner transport roller 68: Cover 8: Developing device 80: Developing device housing 81: Developing device housing 811, 812, 813, 814: conveying path of developing device housing 82, 83: developing device Side walls 821, 831: Support holes 822, 832: Engagement holes 84: Cover walls of developing device housing 841, 842: Toner receiving openings 843, 844: Connection flange 85: Developing roller 86: Supply roller 87: Downstream side Stirring means 88: Upstream stirring means 7: Mounting plate 10: Charging corona discharger 12: Cleaning blade 14: Support shaft 16: Coil spring 18: Flexible joint 30: Developer regulating means 32: Regulation blade 33: Mounting member 34 : Laser unit 340: Laser beam 36: Transfer roller 38: Registration roller pair 91: Developer application means 92: Downstream stirring and conveying means 93: Upstream stirring and conveying means 94: Front cutting board

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yu Watanabe 1-2-28 Tamazo, Chuo-ku, Osaka-shi F-term (reference) 2H034 BF00 CB01 2H077 AA12 AA14 AA37 AC01 AC16 CA03

Claims (4)

[Claims] A photosensitive drum rotatably disposed;
A developing device that applies toner to the electrostatic latent image formed on the peripheral surface of the photoconductor drum to develop the toner image, and a cleaning device that removes residual toner attached to the peripheral surface of the photoconductor drum. A cleaning blade of the cleaning device is disposed above the photosensitive drum, and a residual toner removed from a peripheral surface of the photosensitive drum by the cleaning blade disposed above the developing device. And a bottom wall forming a toner collecting portion having a toner drop port connected to a developing housing of the developing device, wherein the bottom wall is formed of the toner collecting portion. And guiding the residual toner removed by the cleaning blade to the toner collecting portion. Toner collecting device of an image forming machine according to. 2. The toner falling port is provided at both ends in the width direction of the bottom wall, and the bottom wall is removed by the cleaning blade toward the toner drop ports provided at both ends in the width direction. The toner recovery device for an image forming apparatus according to claim 1, wherein the toner recovery device is configured to guide the residual toner that has been formed. 3. The toner collecting device according to claim 1, wherein a toner conveying member that conveys the toner toward the toner drop port is disposed in the toner collecting section. 4. The toner dropping port is provided at each of both ends in the width direction of the bottom wall, and the toner conveying member conveys the toner in the toner collecting section from the center to both ends. 4. The toner collecting device of the image forming machine according to 3.