JPH01126672A - Toner recovering device - Google Patents

Abstract

PURPOSE:To contain much toner with high filling degree and to compactly set a collecting container by forming the recovery container to which acceleration is given so that its cross-sectional area perpendicular to a motion direction can be altered. CONSTITUTION:The recovery container 13 has a toner receiving port 13a on one edge side and such motion that the container can be fully filled with the toner is given to the collecting container 13, so that it can be compactly set in a space below a cleaning device 9. Besides to that, it is formed in such a shape that the cross-sectional area is different according to the motion direction in order to contain the toner as much as possible. In such a shape, much toner can be contained in spite of small volume because the cross-sectional area on the innermost side, where the filling concentration of the toner is higher, is larger than that on an entrance side. Thus, the recovery container can be compactly set and much toner can be effectively contained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a toner recovery device in an image forming apparatus such as an electrophotographic copying machine, and more specifically, toner recovery device for removing toner from the surface of an image bearing member such as a photosensitive drum with a cleaning device. , relates to a toner collection device that is dropped into a collection container and collected.

[Background of the invention]

In the toner collection device described above, the toner receiving port of the collection container is provided on one end side, and an eccentric rotating cam having a step on the circumference is used to collect and store the toner in the collection container. The cam is displaced against the spring bias toward one end edge where the toner receiving port is provided, and the cam falls onto the small-diameter circumferential surface at the stepped portion of the cam. A toner recovery device is known from Japanese Patent Laid-Open No. 58-54369, which repeatedly applies large accelerations that are stopped by a small-diameter circumferential surface.

However, with this toner collection device, it is not possible to easily adjust the magnitude of the acceleration applied to the collection container, and the collection container is only filled with toner to the side opposite to the edge where the toner receiving opening is provided. If a stepped eccentric cam or spring is installed that provides an acceleration of Acceleration is limited to a lower level, and therefore toner tends to accumulate on the toner receiving opening bone.In order to fully store toner in the collecting container, the height of the collecting container must be adjusted not only at the toner receiving opening but also from above. Even distant parts must be made higher, which poses problems such as an increase in the size of the image forming apparatus.

In addition, a toner collection device was developed in Japanese Patent Application Laid-Open No. 5-11301 that uses an optical sensor to detect the pile of toner that accumulates in the toner receiving eye of the collection container, and uses that information to forcibly vibrate the collection container.
It is known from Publication No. 9-231575, but this 1
In the toner collection device, not only does the detection by the optical sensor tend to be inaccurate due to toner contamination, but also the toner receiving opening of the collection container must be located in the center or the height must be increased. There is a problem in that it is difficult to stably store toner in the collection container and to downsize the device.

[Purpose of the invention]

The present invention has been made with the aim of solving the above-mentioned problems with the conventional toner collection device.The present invention has been made with the aim of solving the above-mentioned problems with the conventional toner collection device. It is an object of the present invention to provide a toner collection device that can accommodate a large amount of toner with a high filling degree and can compactly install a collection container in an image forming apparatus.

[Structure of the invention]

The present invention provides a toner collection device that removes toner from the surface of an image carrier of an image forming apparatus using a cleaning device and collects the toner by dropping the toner into a collection container. A container that is reciprocated in the direction of the other end and is accelerated by colliding with a fixed member each time the container moves toward the other end, and the cross-sectional area perpendicular to the direction of movement changes. The present invention provides a toner recovery device characterized in that the above object is achieved by this configuration.

〔Example〕

The present invention will be explained below using illustrated examples.

FIG. 1 is a schematic side view showing an example of an image forming apparatus equipped with the toner collecting device of the present invention, FIG. 2 is a partial side view showing an example of the toner collecting device of the present invention, and FIGS. Partial front view showing an example of a recovery device, FIGS. 5A, B, and C
6 is a perspective view showing examples of different collection containers, and FIG. 6 is a graph showing changes in toner storage capacity and acceleration of the collection containers.
FIG. 7 is a graph showing the acceleration of the collection container and the state in which it is filled with toner.

The image forming apparatus shown in FIG. 1 includes a photosensitive drum 1 which is an image bearing member.
rotates in the direction of the arrow, the charger 2 uniformly charges the surface of the photosensitive drum 1, and the image exposure device 3 using a laser beam scanner performs image exposure by dot exposure on the charged surface of the photosensitive drum 1. to form an electrostatic image, one of the developing devices 4 to 6 develops the electrostatic image into a toner image of yellow, cyan, magenta, etc., and the surface of the photosensitive drum 1 on which the toner image is formed. When the transfer device 79 passes through the inactive position of the separator 8 and the cleaning device j9 and enters the second rotation, it is charged again, charged by the fat 2, and an electrostatic image is formed by the image exposure device 3. .

Developing is performed using one of the developing devices 4 to 6 different from the previous one, and the same process is repeated even in the third rotation.
A color image consisting of a combination of three-color toner images is formed on the photosensitive drum 1, and the color image is transferred by the transfer device 7 to a recording paper fed by the paper feeding means IO, thereby the recording paper onto which the color image is transferred. is separated from the photosensitive drum l by a separator 8, and transferred to the fixing device 1 by a transfer device 11.
2, the fixing device 12 fixes the color image on the recording paper, and the recording paper is discharged outside the machine. Then, residual toner is removed from the surface of the photosensitive drum 1 onto which the color image has been transferred by the cleaning device 9, and the state returns to the state where the next color image can be formed again.

The cleaning device 9 scrapes off toner on the surface of the photosensitive drum 1 with a scraping member 9a, and removes the toner from the guide plate 9.
The toner is guided to the toner conveying means 9c by the toner conveying means 9c, and the toner is conveyed to one end side in the width direction of the cleaning device W9 by the toner conveying means 9c, and is dropped into the collection container 13 through a drop conduit 9d provided at the end. Although a blade is used as the scraping member 9a and a screw conveyor is used as the toner conveying means 9c, the toner is not limited to this, and it is also possible to scrape off with a rotating brush or the like and convey it with a belt conveyor or the like.

In the example shown in FIG. 1, the collection container 13 is placed below the transfer device 11 and the fixing device 12, but in the example shown in FIGS.
It may be arranged below the cleaning device 9 as shown in the figure. However, in the arrangement shown in Figure 1,
Since the toner head is large, the toner moves to the back from the toner receiving port 13a without forming a pile in the collection container 13, and the position of the drop pipe 9d is on the side of the transfer device 11. It now comes off in the opposite direction, and the drop pipe 9
Since the connection between the drop pipe 9d and the collection container 13 is located below the transfer device 11, even if toner were to leak from the connection between the drop pipe 9d and the collection container 13,
The recording paper will not be contaminated, and the collection container 1
3 from the image forming apparatus, the arrangement shown in FIG. 1 is preferable because it provides a degree of design freedom in that it can be taken out to the left of the figure, to the front, or to the back. .

Although the drive mechanism of the collection container 13 is omitted in Fig. 1,
The drive mechanism is the collection container 13 shown in FIGS. 2 to 4.
Since the drive mechanism is the same as the one shown in FIG.

As shown in FIGS. 1 to 4, the collection container 13 has a toner receiving port 13a on one edge side, and as described below, is given a movement that allows it to be fully filled with toner, so that the cleaning device 9 In order to be installed compactly in the space created below the toner and to accommodate as much toner as possible, it is formed into a shape with a cross-sectional area that differs in the direction of movement as shown in Figures 3-4 and 5. . 3rd, 4th
The shape shown in the figure and FIG. 5A has a constant width, and the height of the opposite edge is higher than that of the edge where the toner receiving port 13a is located, and the shape of FIG. 5B has a constant width. The width is constant, and the width is wider at the opposite edge than at the edge where the toner receiving opening 13a is located. With such a shape, the cross-sectional area a on the back side where the toner packing density is high is larger than the cross-sectional area a on the entrance side, so a large amount of toner can be accommodated in a small volume. However, depending on the shape of the empty space of the image forming apparatus in which the collection container 13 is installed, the height on the back side may be lower than the height on the entrance side as shown in FIG. 5C.
The available space in the image forming apparatus may be utilized to the maximum extent for installing the collection container. Further, the collection container 13 as described above is held so as to move integrally with the holding tray 14 within the image forming apparatus so that it can be taken out from the image forming apparatus and the collected toner can be removed.

The holding tray 14 is held by a fixed frame 15 of the image forming apparatus so as to be movable in the direction of one end edge having a toner receiving opening 13a in which the toner storage chamber of the collection container 13 is expanded and the opposite edge. The collection container 13 is biased toward the opposite edge of the collecting container 13 from the one end edge having the toner receiving opening 13a by a fully tensioned spring 17 with a spring hook 16 provided on the side. Note that the holding plate 14 may come into contact with the fixed frame 15 through rollers with low friction;
It is preferable that contact be made with a slider made of resin or the like having an appropriate coefficient of friction so that the reciprocating movement is smooth and the holding plate 14 does not bounce. The holding plate 14 is moved against the bias of the spring 17 by an actuating means 18 such as a stepped eccentric cam (FIG. 3), a stepped surface cam (FIG. 4), or an electromagnetically driven plunger. The actuating means 1 is displaced toward one end edge having the toner receiving port 13a.
When the actuator 8 is released from its operation due to the step of the cam or the de-energization of the electromagnet, it moves to the opposite side due to the bias of the spring 17 and repeatedly collides with the fixing member 19 provided on the fixing frame 15. In this way, as the holding plate 14 collides with the fixed member 19, the occurrence of collision noise and vertical vibration is reduced.
A toner receiving port 1 is provided in a collection container 13 that is integrated with a holding tray 14.
It is possible to apply a large acceleration to move the toner received from 3a to the opposite edge side and sequentially fill the toner storage chamber from the back.

Note that the acceleration can be easily controlled by moving the position of the spring hook 16 or the fixing member 19. The movement of the fixing member 19 is limited within the maximum displacement range of the holding tray 14 provided by the actuating means 18. Therefore, in the illustrated example, the position of the spring hook 16 is moved by a motor 20 provided on the fixed frame 15, and an acceleration sensor 21 is also provided on the holding tray 14, and the control device 22 drives the motor 20 based on the information. The position of the spring hook 16 is moved under control so that the acceleration can be kept constant regardless of changes in the amount of toner in the collection container 13.

However, even if the acceleration is not controlled as described above, the acceleration is applied by the collision with the fixed member 19, which makes it possible to apply the acceleration to the lower surface of the stepped portion of the stepped cam. Compared to the collection device, the collection container 1
The rate at which the acceleration decreases as the amount of toner in the toner increases is significantly reduced, and the collection container 13 can be uniformly filled with toner at a high density.

Figure 6 shows the relationship between the toner storage capacity of the collection container and the acceleration α when the acceleration is not controlled, and the dotted curves A and B
In the case of the conventional toner recovery device, the solid curve C indicates the urethane 7. This is a case of the toner collection device of the present invention which is provided with a cushioning member 19a made of rubber. Note that other rubbers such as silicone rubber and natural rubber, rubber foam, leather, or springs may also be used for the buffer member 19a.

Regarding FIG. 6, in order to fill the collection container 13 with toner from the back side at high density, it is preferable that α is kept at 1.0G or more. From the viewpoint of suppressing vibrations, it is preferable that α does not exceed 2.0G, but in the case of a conventional toner collection device, if α is kept at 1.0G or more, the amount of toner in the collection container 13 is small. is larger than 2.0G, it becomes impossible to suppress collision noise and vertical vibration, and α is set to 2.0G.
If you try to keep it below G, then when the amount of toner in the collection container 13 increases, α will be below 1.0G or even further.
0, 5 will not be able to fill the toner fully.
It becomes below G.

On the other hand, in the case of the toner collection device of the present invention, it is possible to maintain α within the range of 1.0G to 2.0G without controlling α, reduce the generation of impact noise and harmful vibrations, and 1
3 can be filled with toner at high density.

To explain KEPCO's relationship between α and the situation in which toner is filled into the collection container 13 using FIG. The toner filling area F keeps its growth front Pa parallel to the back edge of the collection container 13 and grows in the direction of the edge where the toner receiving port 13a is located (therefore, the toner filling area F grows in such a way that it advances toward the edge where the toner receiving port 13a is located). When the toner starts to overflow, the collection container 13 is almost completely filled with toner, but when α reaches 0.5G, the collection container 13 is separated from the toner receiving port 13a by the growth front Fa of the toner filling area F. Since the side wall of the collection container 13 is largely receded, even when toner overflows into the toner receiving port 13a, the side wall where the growth front Fa is still receding is equivalent to the toner storage chamber of the collection container 13. If α is 0, it goes without saying that even if toner overflows at the toner receiving port 13a, most of the other parts will remain empty.
To fill 3 with toner, α is 0.5G.
It is necessary that the force is above 1.0 G, and particularly preferably 1.0 G or above. Note that the hatched areas in FIG. 7 are areas where unfilled toner is present, and the white areas are areas where there is almost no toner.

The above-mentioned preferable upper limit of α of 2.0G is for the conventional toner collection device that obtains acceleration by collision with the lower surface of the stepped cam.In the toner collection device of the present invention, impact noise and Since the occurrence of harmful vibrations is reduced, the upper limit can be increased to about 3.0G. In particular, in the example shown in FIG. 4 in which a stepped surface cam is used as the actuating means 18, force is applied in the axial direction of the cam. Compared to the example shown in the figure, impact noise and harmful vertical vibrations are much less generated. Furthermore, the toner collection device can be made compact and the drive system can be simplified.

As described above, in the toner recovery device of the present invention, large acceleration is applied to the recovery container 13 without generating impact noise or harmful vibrations. As shown, the height or width of the toner storage chamber can be made larger on the back side than on the toner receiving opening 13a side, so that it can accommodate a large amount of toner. In order to increase the toner storage capacity of the collection container 13, not only the height but also the width on the back side may be increased.This allows the collection container 13 to accommodate toner compactly installed in the image forming apparatus. As the amount increases, the period for removing the collected toner or replacing the collection container 13 becomes longer.

In the examples shown in FIGS. 3 and 4 in which the acceleration sensor 21 is provided, not only can the acceleration α be controlled to be constant, but also α can be controlled to be constant according to the amount of toner contained in the collection container 13 as shown in FIG. Based on this information, the control device 22 determines when the collection container 3 is full of toner and collects the toner by using the change in α or the movement of the spring hook 16 to keep α constant. A warning can be given to remove or replace the toner in the container 13. In this case, the fixing member 19
Alternatively, an impact pressure sensor is provided at the collision part of the holding tray 14,
If the warning trigger is determined from the ratio of this information and the information of the acceleration sensor 21, the accuracy can be improved.

In a particularly preferred embodiment of the present invention, a toner collection device is incorporated into the image forming apparatus as shown in FIG. 1, and the collection container 13 is arranged as shown in FIGS. 3 to 5A.

A stepped surface cam is used as the actuating means 18 as shown in FIG. The stroke of the holding plate 14 stopped by 19 is 5 m.
m, and the rotation speed of the stepped surface cam is about 50 rpm+,
α is 1.0G to 2.0G by controlling the position of the spring hook 16.
There is an example in which a range of toner is kept constant and a warning is given that the collection container 13 is about to be full of toner from information on the amount of movement of the spring hook 16. This allows the collection container 13 to be stably filled with toner at a high density without contaminating the recording paper with collected toner, with little impact noise or vertical vibration, and toner removal from the collection container 13 or It is possible to obtain the effects that the replacement cycle can be lengthened and the durability of the toner collection device is also excellent.

In order to allow the collection container 13 to be taken in and out horizontally, the holding tray 14 has its left wall in the direction perpendicular to the reciprocating direction in the example of FIG. 1, and in the reciprocating direction in the example of FIG. The left side wall in one figure, and the right side wall (not shown in the example in Figure 3), are configured to collapse horizontally. In addition, the collection container 13 can be taken in and out horizontally, and the drop pipe 9d of the cleaning device 9 is designed to prevent toner from leaking out from the part where the drop pipe 9d contacts the toner receiving port 13a of the collection container 13. A flange cover is provided at the lower part of the conduit 9d. It is preferable that this flange lid is slidably engaged with the outer shape of the drop conduit 9d so as to come into contact with the upper surface of the recovery container 13, rather than being fixed to the drop conduit 9d.

〔Effect of the invention〕

The toner recovery device of the present invention generates less impact noise and vibration, and
Since the cross-sectional area of the collection container is changed in the direction of movement,
The collection container can be installed compactly in the image forming apparatus, and a large amount of toner can be efficiently stored in the collection container, and the cycle of removing or replacing toner in the collection container I can be extended. play.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an example of an image forming apparatus equipped with the toner collecting device of the present invention, FIG. 2 is a partial side view showing an example of the toner collecting device of the present invention, and FIGS. Partial front view showing an example of a recovery device, FIGS. 5A, B, and C
6 is a perspective view showing examples of different collection containers, and FIG. 6 is a graph showing changes in toner storage capacity and acceleration of the collection containers.
FIG. 7 is a graph showing the acceleration of the collection container and the state in which it is filled with toner. 1... Photosensitive drum, 2... Charger, 3...
Image exposure device, 4-6... Developing device, 7... Transfer device, 8... Separator, 9... Cleaning device, 9a... Scraping member, 9b... Guide plate, 9c
... Toner conveyance means, 9d ... Drop pipe, 10.
...paper feeding means, 11... receiving and passing device, 12
...Fixing device, 13...Collection container, 13a
... Toner receiving port, 14 ... Holding tray, 15 ...
Fixed frame, 16... Spring hook, 17... Spring, 18... Operating means, 19... Fixed member, 19a... Buffer member, 20... Motor, 21... Acceleration sensor, 22...control device. Figure 4 Figure 5 (, 3> (go) ° 6 Figure 200 400 600 Bo. Toner 4 sentence 's-t<':i>

Claims (1)

[Claims] In a toner recovery device that removes toner from the surface of an image carrier of an image forming apparatus using a cleaning device and collects the toner by dropping the toner into a recovery container, the recovery container has a toner receiving opening on one edge side, and the one edge and the other edge are connected to each other. It is made to reciprocate in the direction of
A toner collecting device characterized in that the container is accelerated by colliding with a fixed member each time it moves toward the other edge, and the cross-sectional area perpendicular to the direction of movement changes.