JPH087521B2 - Image forming device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus, and in particular, after forming a toner image on an image carrier and transferring the toner image on a recording paper. The present invention relates to an image forming apparatus that removes toner remaining on the surface of an image carrier by a cleaning unit.

[Background of the Invention]

As a toner recovery device for recovering the toner removed by the cleaning means, an eccentric rotation having a step on the peripheral surface is provided with a toner receiving port of the recovery container on one end side, and moreover, the recovery container is filled with toner and accommodated therein. The cam displaces the collection container against the bias of the spring to the one edge side where the toner receiving port is provided, and drops it on the small diameter peripheral surface at the stepped part of the cam, and the collection container is spring-loaded to the opposite side. Japanese Patent Laid-Open No. 58-54369 discloses a toner collecting device which repeatedly gives a large acceleration by stopping the motion due to the force on the small diameter peripheral surface of the cam. However, this toner recovery device
Since the collection container is swingably supported, not only is the acceleration to move the toner in the collection container given, but also vertical vibration is given, so that the filling movement of the toner is not effectively performed, and the toner is not received. There is a problem that it is easily deposited on the mouth. Therefore, if a large amount of toner is to be stored in the collection container, the height of the collection container must be increased, which results in an increase in size of the image forming apparatus. Further, since the acceleration is applied by the collision of the stepped cam with the small diameter peripheral surface, the magnitude of the acceleration cannot be easily adjusted, and the acceleration is applied so that the toner can be moved satisfactorily. When the stepped eccentric cam or spring is set, not only the wear of the cam and the cam follower becomes large, but also the impact drop and the vertical vibration of the recovery container become large, which cannot be suppressed.

On the other hand, there is a toner recovery device in which an optical sensor detects a pile of toner accumulated in the toner receiving port of the recovery container and the vibration of the recovery container is forced based on the detected information.
It is known from the publication 59-231575. In this toner collecting device, not only the detection by the optical sensor is likely to be inaccurate due to toner stains, but also the toner receiving port of the collecting container has to be provided in the central part or the height has to be increased.
There is a problem that it is difficult to achieve stable toner storage in the collection container and miniaturization of the device.

[Object of the Invention]

In consideration of the above-mentioned problems, the present invention can extend the toner removal period of the toner recovery container by fully storing the toner in the toner recovery container, and can efficiently pack the toner in the toner recovery container. It is an object of the present invention to provide a compact image forming apparatus which can be made and has less impact noise and vibration.

[Structure of Invention]

The present invention is an image forming apparatus in which a toner image is formed on an image carrier, the toner image is transferred onto a recording paper, and then the toner remaining on the surface of the image carrier is removed by a cleaning unit. A collection port for collecting the collected toner is provided at one edge, and a collection container for housing the collected toner, a moving means for horizontally reciprocating the collection container, and the moving means are separate means. ,
Collision means for colliding with the collection container via a cushioning member having a rubber hardness of 65 to 70 when the collection container moves from the one edge toward the opposite edge. This is a characteristic image forming apparatus, and the object is achieved by this configuration.

〔Example〕

 Hereinafter, the present invention will be described with reference to illustrated examples.

FIG. 1 shows an embodiment of the present invention, and is a schematic side view showing an image forming apparatus equipped with a toner collecting device, FIG. 2 is a partial side view showing the toner collecting device, and FIGS. FIG. 5 is a partial front view showing an example of a toner collecting device, FIG. 5 is a perspective view showing a different example of a collecting container, FIG. 6 is a graph showing changes in toner storage amount and acceleration of the collecting container, and FIG. 7 is a collecting container. 5 is a graph showing the acceleration of the toner and the state of being filled with toner.

In the image forming apparatus shown in FIG. 1, the photosensitive drum 1, which is an image carrier, rotates in the direction of the arrow, the charging device 2 uniformly charges the surface of the photosensitive drum 1, and image exposure using a laser beam scanner device is performed. The device 3 performs image exposure by dot exposure on the charged surface of the photosensitive drum 1 to form an electrostatic image, and one of the developing devices 4 to 6 develops the electrostatic image by using any toner such as yellow, cyan, and magenta. A transfer device that develops an image and the surface of the photosensitive drum 1 on which the toner image is formed is placed in an inoperative state.
7. After passing through the positions of the separator 8 and the cleaning device 9 and entering the second rotation, charging by the charging device 2 again, formation of an electrostatic image by the image exposing device 3, and developing devices 4 to 6 different from the previous ones.
Development is carried out, and the same steps are repeated even after the third rotation, to form a color image on the photosensitive drum 1 by combining three color toner images, and the color image is fed by the paper feeding means 10. The transfer device 7 transfers the transferred color image onto the recording paper, and the recording paper on which the color image is transferred is separated from the photosensitive drum 1 by the separator 8. The transfer device 11 sends the recording paper to the fixing device 12, and the fixing device 12 transfers the color image. Fix the image on the recording paper and eject the recording paper to the outside of the machine. Then, the cleaning device 9 removes the residual toner from the surface of the photosensitive drum 1 onto which the color image has been transferred, and returns to a state where the next color image is formed again.

The cleaning device 9 scrapes off the toner on the surface of the photosensitive drum 1 with the scraping member 9a, and the scraped toner is guided by the guide plate 9b.
The toner is conveyed to the toner conveying means 9c by the toner conveying means 9c and conveyed to one end side in the width direction of the cleaning device 9 and dropped into the collecting container 13 by the dropping pipe 9d provided at the end. In addition,
In the illustrated example, a blade is used as the scraping member 9a, and a screw conveyor is used as the toner conveying means 9c, but the invention is not limited to this, and the scraping member 9a may be scraped by a rotating brush or the like and conveyed by a belt conveyor or the like. Good.

Although the recovery container 13 is arranged below the delivery device 11 and the fixing device 12 in the first example, it may be arranged below the cleaning device 9 as shown in FIGS. 2 to 4. Good. However, in the arrangement of FIG. 1, since the toner drop is large, the toner moves to the back from the toner receiving port 13a portion without forming a ridge in the collecting container 13, and the dropping pipe line 9d. The position of is removed to the side of the delivery device 11, and since the connection portion of the dropping pipe line 9d and the collection container 13 is located below the delivery device 11, from the connection portion of the dropping pipe line 9d and the collection container 13. Even if toner should leak, the recording paper will not be contaminated. Furthermore, the recovery container 13 can be taken out from the image forming apparatus to the left in the figure, Alternatively, the arrangement shown in FIG. 1 is preferable because the degree of freedom in design is obtained in that it can be taken out to the back side.

Although the drive mechanism of the recovery container 13 is omitted in FIG. 1,
The drive mechanism is the same as the drive mechanism of the recovery container 13 shown in FIGS. 2 to 4, and therefore the recovery container 13 will be described below mainly with reference to the drawings of FIG.

As shown in FIGS. 1 to 4, the recovery container 13 has a toner receiving port 13a at one end side thereof, and as described below, is given a motion capable of fully filling the toner. In the image forming apparatus, it is integrally held in at least the moving direction so that the toner can be compactly installed in a space generated below the image forming apparatus, and the toner collected from the image forming apparatus can be removed. .

The holding plate 14 is held by a fixed frame 15 of the image forming apparatus so as to be linearly movable in the direction of one end edge having the toner receiving port 13a in which the toner storage chamber of the collection container 13 is widened and the opposite edge, A toner receiving port 13 of the collecting container 13 is provided by a spring 17 stretched between a spring hook 16 provided on the fixed frame 15 side.
It is biased toward the edge opposite to the edge having a.
The holding plate 14 is brought into contact with the fixed frame 15 by a slider such as a resin having an appropriate friction coefficient so that the holding plate 14 is smoothly reciprocated and the holding plate 14 does not bounce. Is preferably performed. And the holding plate 14 is the third
A stepped eccentric cam whose rotation shaft is supported at right angles to the movable surface of the holding tray 14 as shown in the drawing, and a rotation shaft which is supported in the same direction as the moving direction of the holding tray 14 as shown in FIG. , An actuating means such as an electromagnetically driven plunger that does not generate a component force in the vertical direction at right angles to it by applying a force in the movable direction to the stepped surface cam or the holding tray 14 with which the cam follower contacts at the bottom or the top By 18 is displaced to the one end side having the toner receiving port 13a of the collection container 13 against the bias of the spring 17, and when the operating means 18 releases the operation by the step portion of the cam or the non-excitation of the electromagnet, The movement of the spring 17 to the opposite side by the bias of the spring 17 and the collision with the fixing member 19 provided on the fixing frame 15 are repeated. As a result, in the collection container 13 integrated with the holding dish 14,
There is little vertical vibration that reduces the toner transport effect of impact noise and acceleration, and a large acceleration to efficiently transfer the toner received from the toner receiving port 13a to the opposite edge side and to fill the toner storage chamber in high density sequentially from the back. And the durability of the toner recovery container is excellent even if a large acceleration is applied. Among the above-mentioned actuating means 18 that does not cause vertical vibration, the stepped surface cam of FIG. 4 has a simple cam drive mechanism, and therefore the image forming apparatus can be configured more compactly. Most preferred.

In the toner collecting apparatus of the embodiment as described above, in the conventional toner collecting apparatus, when an attempt is made to give a large acceleration to the collecting container, the impact sound and the vertical vibration become large and cannot be suppressed. It had to be smaller than G (G is the acceleration of gravity), and there was the problem that the wear of the cam and cam follower was remarkable, but even if the acceleration was increased to about 3.0 G, the impact noise and vertical vibration would occur. It can be suppressed and has excellent durability. Therefore, even if the height of the toner storage chamber as shown in FIG. 5 is higher on the inner side than on the toner receiving port 13a side or wider on the inner side as shown in FIG. Can be filled with toner to a full
The toner removal or replacement period of 13 can be extended.

Further, in the toner collecting apparatus of the embodiment, the acceleration is applied by the collision with the fixing member 19, so that the acceleration can be easily suppressed. That is, the acceleration can be easily controlled by moving the position of the spring hook 16 or the fixing member 19. When controlled by the movement of the fixing member 19, it 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 the motor 20 provided in the fixed frame 15, and the acceleration sensor 21 is further provided in the holding tray 14, and the control device 22 drives the motor 20 according to the information. The position of the spring hook 16 is controlled to be moved so that the acceleration can be kept constant regardless of the change in the amount of toner in the collection container 13.

However, even if the acceleration is not controlled as described above, the acceleration is given by the collision with the fixed member 19, so that the conventional toner that is given by the collision with the stepped lower surface of the stepped cam is used. Compared to the collection device, the collection container 13
The rate of decrease in acceleration due to an increase in the amount of toner inside is significantly reduced, and it becomes possible to fill the recovery container 13 with toner at a uniform high density. This point will be described with reference to FIG.

FIG. 6 shows the relationship between the amount of toner contained in the recovery container and the acceleration α when the acceleration is not controlled, and is shown by the dotted curves A and B.
In the case of the conventional toner collecting apparatus, the solid curve C is the case of the toner collecting apparatus of the present invention in which the impact surface of the fixing member 19 is provided with the cushioning member 19a of urethane rubber. The cushioning member 19a
Other silicone rubber, rubber such as natural rubber, rubber foam, leather, or spring may be used as the rubber. Referring to FIG. 6, α is preferably kept at 1.0 G or more in order to highly densely fill the collection container 13 with toner from the back side. Further, in the conventional toner collection device, in particular, impact noise and vertical vibration From the viewpoint of suppression of, it is preferable that α does not exceed 2.0G,
In the case of the conventional toner collecting device, if α1.0G or more is maintained, as shown in the curve A, α becomes larger than 2.0G in a state where the toner amount in the collecting container 13 is small, and the impact noise and the vertical movement If the vibration cannot be suppressed and α is kept at 2.0 G or less, as shown by the curve B, when the toner amount in the collection container 13 increases, α is 1.0 G or less or further
13 will not be able to be fully filled with toner and will fall below 0.5G. On the other hand, in the case of the toner collecting apparatus of the embodiment, 1.0 G
It can be maintained in the range of up to 2.0 G, the impact noise and the vertical vibration can be reduced, and the collection container 13 can be filled with the toner with high density.

The relationship between α and the situation where toner is filled in the collecting container 13 will be described with reference to FIG. 7. When α is 1.0 G or more, the toner indicated by cross-hatching fills the toner storage area of the collecting container 13 to the toner storage chamber ceiling. F grows by keeping its growth front Fa substantially parallel to the inner side edge of the collection container 13 and advancing in the direction of the edge having the toner receiving port 13a, so that the toner may overflow into the toner receiving port 13a. However, when α becomes 0.5 G, the growth front Fa of the toner filling area F is on the side wall of the collection container 13 distant from the toner receiving port 13a. Since the shape is largely retracted, even if the toner overflows into the toner receiving port 13a, a considerable space remains in the toner storage chamber of the recovery container 13 on the side wall side where the growth front Fa is still retracted. become. Needless to say, if α is 0, even if the toner overflows at the toner receiving port 13a, the other portions remain almost empty. Therefore, in order to fully fill the recovery container 13 with toner, α needs to be 0.5 G or more, and particularly preferably 1.0 G or more. The hatched area in FIG. 7 is an area where unfilled toner is present, and the white area is an area where there is almost no toner.

In the example of FIGS. 3 and 4 in which the acceleration sensor 21 is provided, not only the acceleration α can be controlled so as to be constant, but also α as shown in FIG.
Changes, or springs to keep α constant
Using the movement of 16 or the fixing member 19, the control device 22 judges the time when the toner is full in the collection container 13 based on the information and warns the toner removal or replacement of the collection container 13. You can In this case, if an impact pressure sensor is further provided at the collision portion of the fixing member 19 or the holding tray 14 and the warning timing is determined from the ratio of the information of the impact pressure sensor and the information of the acceleration sensor 21, the accuracy can be further improved. . As described above, the removal or replacement of the toner in the collection container 13 can be minimized.

As a particularly preferred embodiment of the present invention, as shown in FIG. 1, a toner collecting device is incorporated in the image forming apparatus, the collecting container 13 has the shape shown in FIG. Using a stepped surface cam as shown in FIG.
The fixed member 19 is provided with a cushioning member 19a having a rubber hardness of 65 to 70, the stroke of the holding plate 14 stopped by the fixed member 19 is set to about 5 mm, the rotation speed of the stepped surface cam is set to about 50 rpm, α
Is an example in which the position of the spring hook 16 is controlled to be kept constant in the range of 1.0G to 2.0G, and the time when the toner of the recovery container 13 is full is warned from the movement amount information of the spring hook 16. by this,
The image forming apparatus can be configured compactly, the recording paper is not contaminated with the collected toner, the impact noise and the vibration are small, and the toner can be stably stored in the collection container 13 at a high density. As a result, the toner removal or replacement cycle of the collection container 13 becomes longer, and the durability of the toner collection device is excellent.

In order to allow the recovery container 13 to be taken in and out horizontally, the holding plate 14 has a left side wall in the drawing in the direction perpendicular to the reciprocating direction in the example of FIG. 1 and a reciprocating direction in the example of FIG. The left side wall of one figure and the right side wall (not shown in the example of FIG. 4) are configured to fall horizontally. Further, the collection container 13 can be horizontally taken in and out, and moreover, the toner does not leak from the portion where the dropping pipe line 9d of the cleaning device 9 is in contact with the toner receiving port 13a of the collection container 13.
A flange lid is provided at the bottom of the drop pipe 9d. This flange lid is used for collecting container 13 rather than fixing it to the drop pipe 9d.
It is preferably slidably engaged with the outer shape of the drop pipe 9d so as to come into contact with the upper surface of the.

〔The invention's effect〕

The image forming apparatus of the present invention can give a sufficient acceleration to store the toner in the toner recovery container having the recovery port at one end, and the dispersion of the acceleration is small, and the toner is efficiently packed in the toner recovery container. Because you can
The toner removal period of the toner collection container can be extended, and the image forming apparatus can be made compact.
Since a cushioning member having a rubber hardness of 65 to 70 is provided, an impact noise and vibration are reduced.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, and is a schematic side view showing an image forming apparatus having a toner collecting device, FIG. 2 is a partial side view showing the toner collecting device, and FIGS. 3 and 4 are respectively. FIG. 5 is a partial front view showing an example of the toner collecting device, FIG. 5 is a perspective view showing another example of the collecting container, FIG. 6 is a graph showing changes in the toner storage amount and acceleration of the collecting container, and FIG. 6 is a graph showing acceleration and a state where toner is filled. 1 ... Photosensitive drum, 2 ... Charging device, 3 ... Image exposure device, 4-6 ... Developing device, 7 ... Transfer device, 8 ... Separator, 9 ... Cleaning device, 9a ... Scraping Member, 9b ... Guide plate, 9c ... Toner transporting means, 9d ... Dropping line, 10 ... Paper feeding means, 11 ... Transfer device, 12 ... Fixing device, 13 ... Collection container, 13a. Toner receiving port, 14-holding plate, 15-fixing frame, 16-spring mount, 17-spring, 18-step slant cam, 19-fixing member, 19a-impact member, 20 --- Motor, 21 ... Acceleration sensor, 22 ... Control device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-58-54369 (JP, A) JP-A-57-88476 (JP, A)

Claims (1)

[Claims] 1. An image forming apparatus in which a toner image is formed on an image bearing member, the toner image is transferred onto a recording sheet, and then the toner remaining on the surface of the image bearing member is removed by a cleaning unit. A recovery port for recovering the removed toner is provided at one edge, and a recovery container that stores the recovered toner, a moving unit that horizontally reciprocates the recovery container, and the moving unit are separate units. And a collision unit that collides with the recovery container via a cushioning member having a rubber hardness of 65 to 70 when the recovery container moves from the one edge toward the opposite edge. An image forming apparatus characterized by the above.