JPH0758417B2 - Toner recovery device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner collecting device used in an image forming apparatus using electrostatic recording means, such as an electrostatic copying machine and a printer.

(Problems to be Solved by Prior Art) In a well-known image forming apparatus that repeats the step of transferring a movable toner image formed on the surface of an image carrier to a sheet-like transfer material such as paper, the toner is not transferred during transfer. It is difficult to transfer all the image forming toner to the transfer material, and a small amount of toner remains on the surface of the image carrier.

For this reason, it is indispensable to provide a cleaning device for removing such residual toner at each transfer so as not to hinder the next image formation, and in general, the toner of the cleaning device is not provided. Since the storage space is usually not so large, a separate waste toner container is installed so that the waste toner generated at each transfer will not become full, resulting in poor cleaning and deterioration of image quality. Conventionally, a structure in which a cleaning device and a waste toner container are connected by a hollow tube member having a coil-spring-shaped carrier screw installed therein, and the toner is guided and stored in the container by driving the carrier screw Widely used. In such a case, when the toner container is full, this is instructed, and the weight of the waste toner and the average toner amount generated at each transfer are integrated in order to inform the necessity of post-processing such as container replacement. Alternatively, various detection means such as blocking the optical path formed in the container with toner have been proposed and put into practical use.

However, the recent progress in downsizing of the image forming apparatus, the demand for effective utilization of the space in the apparatus due to this, further, the image bearing member normally formed in the shape of a rotating cylinder, and the image forming members arranged around the image bearing member. With the widespread use of image forming apparatuses of a cartridge type that are integrally replaceable, it has been proposed that waste toner is guided and stored from a cleaning device to a space inside a hollow image carrier.

In such a type of toner container, it is difficult to adopt the above-mentioned means based on the weight of toner and the unit usage amount. Also, due to the presence of toner,
Even in the case where the preformed optical path is blocked, the toner in the moving container behaves like dust in the empty space due to rotational movement, etc., which causes the optical path to be contaminated and malfunction. May occur.

Therefore, the image carrier, which is a container, becomes full, or
If the toner solidifies in the conveying portion, excessive torque may be applied to the conveying screw.

FIG. 4 is a diagram schematically showing such a situation, however, as the number of revolutions of the conveying screw and the amount of toner become excessive, the torque of the conveying screw increases and the toner is displaced from its normal position.

That is, the conveying screw maintains a predetermined rotation speed at a predetermined position until the stored toner reaches a predetermined quantity, but when the toner becomes excessive, the rotation speed sharply decreases and a part of Since the driving force is applied while the position of the screw is substantially fixed, the positions of the other screw parts are gradually changed.

The present invention has been made to cope with such a situation, and in the case where the toner is conveyed from the cleaning device of the image forming apparatus to the waste toner container by the coil spring-shaped conveying screw, the toner amount can be reliably measured. It is an object of the present invention to provide a toner recovery device that can be constantly detected and used in a stable state.

(Means for Solving the Problem, Its Action) In order to achieve the above object, the present invention provides a toner recovery for recovering the toner removed from the surface of an image carrier into a recovery container, which is used in an image forming apparatus. In the apparatus, a tube for guiding the toner removed from the surface of the image carrier to a collection container, and a tube for transporting the toner removed from the surface of the image carrier to the collection container through the tube. A rotation screw provided on the tube, a pipe slidably provided on the outer periphery of the tube so as to connect the tube to a separation part of the tube on the front side of the u-turn part of the tube, and rotation of the screw. A disc member provided on the pipe, projecting in a direction intersecting the axial direction, and having one end attached to the screw, A rotating member provided so as to be located inside the material, a dust blocking member provided inside the disk member for preventing toner from entering the disk member, and an irregular force acts on the screw depending on a toner state. Then, a detection unit that detects a displacement of the disk member that is displaced in association with the rotating member that is displaced in the rotation axis direction of the screw is provided.

With this configuration, it is possible not only to detect that the toner reaches a predetermined amount without error, but
It is possible to carry a sufficient amount of toner.

(Explanation of Embodiments) FIG. 1 is an explanatory view showing an embodiment in which the present invention is applied to a copying machine provided with a rotating cylindrical photoconductor.

As shown in the figure, the cleaning device 2 is disposed close to the photoconductor 1, and the residual toner on the surface circle of the photoconductor is collected by the cleaning device, and when it is accumulated to some extent, it is driven by a drive source (not shown). The conveying screw 4 feeds the inside of the tube 3 from the left side to the right side in the figure, and further guides it through the tube extending to the outside of the cleaning device to a waste toner container which is a void in the photoconductor.

In such a case, according to the present invention, the toner detecting means 6 is arranged at a proper position outside the cleaning device of the tube.

As shown in FIG. 2, in the toner detecting means 6, the tube 3 is divided into a portion 3a inside the cleaning device and a portion 3b outside thereof for guiding the toner to the photoconductor. The ends of both parts are slightly separated from each other, and the pipe member 5 is slidably provided in that part.

A hollow disk-shaped disk member 6 made of a transparent material is attached to the pipe member 5.

The conveying screw 4 is internally provided over the tube portion 3a, the pipe member 5, and the tube member 3b, and is rotationally driven by a driving source (not shown) to be guided from the cleaning device side to a waste toner container, that is, a space inside the photoconductor. Shall be done.

A rotating member 7 attached to the conveying screw 4 is arranged in the disc member 6, and the rotating member 7 rotates together with the conveying screw 4 in the disc member 6.

As can be seen from FIGS. 2 and 3, an annular dust blocking member 8 and a dustproof member 90 are arranged in the disk member 6, and these members prevent the toner from entering the disk member. It is designed to prevent Further, a retaining member 10 is also arranged in an annular shape inside the disc member, and the rotating member 7 is rotated by the retaining members at a position equidistant from both inner wall surfaces of the disc member. It is like this.

The rotating member 7 is made of a material having relatively high rigidity such as a metal having a smooth surface, and the dust blocking member 8 and the dust preventing member 9 are both made of sponge, felt, etc. It is configured to sandwich the member 7.

With this configuration, when the toner is conveyed in a normal state, the conveying screw also rotates in a uniform state as a whole, and the rotating member 7 also moves in the disk member 6 at a uniform speed. It will rotate.

When the toner container becomes full and the conveying screw is driven after that, excess toner accumulates in the tube and tends to solidify, which causes excessive torque on the conveying screw, which causes As the rotation cycle of the rotating member changes, a part of the conveying screw is displaced, and the disc member 6 and these integrated pipe member 5 are displaced in the direction of the dotted line in the figure via the rotating member 7 attached to the screw. Will be done.

As shown in FIG. 2, a displacement detector 11 is arranged near the disc member 6, and the disc member 6 and the detector 11 are connected by a connecting rod 11a. Therefore, the displacement of the disk member 6 is detected by a displacement detector, or an appropriate means such as the period detector 12 is used to warn the operator of this, or the device is stopped, and an appropriate process is performed. It is possible to do.

As the displacement detector, for example, a variable resistor whose resistance value is changed by the movement of the connecting rod is incorporated, or the position of the rotating member 7 in the disk member 6 and its rotation cycle are changed. Appropriate ones such as detecting a change in the reflected light of the light projected onto the rotating member can be used.

When using the displacement detector, it is preferable to perform processing such as stopping the operation of the device when the displacement amount reaches an appropriate value within the range of 0.1 to 50.0 mm.

Although the present invention has been described above with reference to the embodiments in which the present invention is applied to the one including the rotating cylindrical photosensitive member, the present invention is not limited to this, and is provided with a toner container of a value type. However, it can be easily understood that it is applicable.

Since the above-described embodiment has the above-described structure, the image forming apparatus using the electrostatic recording means can accurately and reliably store the generated waste toner in any toner container. The state can be detected, maintenance is easy, and a stable cleaning action can be obtained.

(Effect of the Invention) According to the present invention as described above, it is possible to detect that the toner reaches a predetermined amount without error (erroneous detection prevention), and in addition, the screw conveys a sufficient amount of toner. Was realized. Because, according to the present invention, the pipe has a pipe slidably provided on the outer circumference of the tube so as to connect the tube to the separated part of the tube on the front side of the u-turn part of the tube, and further, This is because it has a rotating member attached to the screw so as to be located inside the disk member. Therefore, according to the present invention, on the front side of the u-turn portion of the tube, that is,
Since the displacement of the disc material is detected at the portion where the toner is easily clogged and the displacement amount of the disc member is large, erroneous detection can be prevented. In addition, according to the present invention, the pipe has a pipe slidably provided on the outer periphery of the tube, and further has a rotating member attached to the screw and provided so as to be located in the disc member. Since the displacement of the screw can be detected directly on the outside of the tube, erroneous detection can also be prevented by this, and in addition, the screw shaft is not required and a sufficient amount of toner can be conveyed by the screw. .

[Brief description of drawings]

FIG. 1 is a principal part explanatory view showing an embodiment in which the present invention is applied to a copying machine. 2 and 3 are an enlarged side view and an end view showing a cross section of the toner detection member. FIG. 4 is a graph schematically showing the relationship between the rotation number and the displacement amount of the conveying screw with respect to the accumulated toner. 1 ... Photoconductor, 2 ... Cleaning device, 3 ... Tube, 4 ... Conveying screw, 6 ... Disk member, 7 ... Rotating member, 8 ... Dust blocking member, 9 ... Dustproof member, 10 ... …
Holding member.

Claims (1)

[Claims] 1. A toner recovery device used in an image forming apparatus for recovering toner removed from the surface of an image carrier into a recovery container, for guiding the toner removed from the surface of the image carrier to a recovery container. A tube, a rotating screw provided in the tube for conveying the toner removed from the surface of the image carrier to the collection container through the tube, and the tube on the front side of the u-turn portion of the tube. A pipe slidably provided on the outer circumference of the tube so as to connect the tube to the separated part of the tube, and a disc member provided on the pipe so as to project in a direction intersecting with the rotation axis direction of the screw. A rotary member having one end attached to the screw and provided so as to be located in the disc member; and a rotating member provided in the disc member. The dust blocking member for preventing the toner from entering the disk member, and the displacement of the screw in the direction of the rotation axis of the screw when an improper force acts on the screw depending on the state of the toner. A toner collecting device for detecting the displacement of the disk member.