JPH0710369Y2 - Recovery toner full detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a collected toner full detection device attached to a toner recovery device for recovering residual toner on a latent image carrier in a copying machine or the like, In particular, the present invention relates to an improvement of a collected toner full detection device capable of detecting the full state of collected toner using an optical sensor.

[Prior Art] Generally, in a copying machine or the like, as shown in FIG. 7, the residual toner on the photosensitive drum 1 as a latent image carrier is scraped off by a cleaning blade 2 as a cleaning means and the toner is also removed. After being received by the receiving member 3, it is fed into the toner collecting box 5 via the toner conveying member 4. Then, when the collected toner in the toner collection box 5 becomes full, the toner collection box 5 must be replaced. At this time, it is necessary to reliably detect the full state of the collected toner.

As an example of a conventional device for detecting the fullness of collected toner using an optical sensor, as shown in FIG. 7, an opening 10 is provided in the upper part of the toner collection box 5, and the edge of the opening 10 is transparent. Alternatively, it is provided that the semitransparent housing 11 is formed to bulge upward, and the optical sensors 12 including the light emitting element 12a and the light receiving element 12b are arranged on both sides of the housing 11 so as to face each other. ing.

According to this type, when the toner is gradually filled in the toner collecting box 5 and the toner becomes full, the toner in the housing 11 is also filled, so that the toner in the housing 11 passes through the optical path of the optical sensor 12. It will block. The change in the output of the optical sensor 12 at this time detects the full state of the collected toner.

[Problems to be solved by the invention] However, in this type, when the collected toner becomes full, the toner is filled up to the upper wall position of the toner collection box 5, and then the housing 11 is further filled with the above-mentioned material. Although it is necessary to push up the toner, since the toner conveying means 4 only pushes up the collected toner as a whole,
There is a risk that the toner will not be reliably filled in the housing 11, which makes it difficult to accurately detect the full state of the collected toner, and the full toner is transferred from the seal portion of the toner collection box 5 to the outside. There is also the fear of overflowing.

Furthermore, since the toner recovery box 5 normally extends along the axial direction of the photosensitive drum 1, the distribution of the recovered toner in the toner recovery box 5 may be offset in the longitudinal direction. In such a case, if only the toner part corresponding to the housing 11 part rises, the optical path of the optical sensor 12 will be immediately interrupted, and the collected toner will be erroneously detected as if it were full. This problem can be solved by providing a plurality of optical sensors 12 and housings 11 in the longitudinal direction of the toner recovery box 5, but the number of parts of the recovery toner full detection device unnecessarily increases. ,
There is a problem that the cost of the device increases.

[Means for Solving Problems] The present invention has been made in view of the above problems, and reduces the cost of the apparatus without being affected by the deviation of the toner in the toner collection box. It is an object of the present invention to provide a full-collection-toner detection device capable of extremely accurately detecting the full-state of the collected toner.

That is, the present invention is premised on a recovery toner full detection device attached to a toner recovery device for recovering the residual toner on the latent image carrier cleaned by the cleaning means in the toner recovery box, An optical sensor including a light emitting portion and a light receiving portion is arranged above the toner collecting box, while a flat plate-like float member is floatably provided in the toner collecting box, and the optical member is attached to the float member. A non-transmissive light-shielding protrusion extending upward is provided corresponding to the facing gap of the sensor, and the light-shielding protrusion interrupts the optical path of the optical sensor when the float member rises according to the amount of collected toner. Is a full-collection-toner detecting device for detecting the full state of the full-collection toner by means of the dimension of the float member along the axial direction of the latent-image carrier, and the maximum latent-image forming area. Set more than half and within a high latent image forming area using frequency narrower than the maximum latent image forming area,
It is characterized in that the float member is arranged at a position substantially corresponding to a frequently used latent image forming region along the axial direction of the latent image carrier.

In such a technical means, the toner recovery device may be an independent unit separate from the cleaning device and the latent image carrier, or any one of a unit configured with the cleaning device and the latent image carrier. The type does not matter. Further, the shape and arrangement position of the toner recovery box may be appropriately changed, but in order to ensure the floating operation of the float member, an introduction section for the recovered toner is provided below the toner recovery box. is necessary.

The material of the float member may be appropriately selected, but it is desirable to use a material that is light to some extent because it needs to rise as the collected toner rises. Further, regarding the position of the float member, from the viewpoint of suppressing the floating of the float member by the collected toner from outside the normal latent image forming region as much as possible, the latent image forming region on the latent image carrier which is frequently used. However, in order to effectively absorb the deviation of the toner distribution along the axial direction of the latent image carrier, the dimension of the float member along the axial direction of the latent image carrier should be set. It is necessary to set it to more than half of the maximum latent image forming area. Also, as for the support means for the float member, if it is arranged so as to be supported above the position where the collected toner is introduced, and the float member is automatically raised as the toner rises, it is appropriate. The design may be changed.

Furthermore, it is necessary to design the above-mentioned light-shielding protrusion so that the optical path of the optical sensor can be blocked at least when the toner is full.

[Operation] According to the technical means described above, when the residual toner on the latent image carrier cleaned by the cleaning means is gradually collected in the toner collection box, the toner gradually rises in the toner collection box. When the toner reaches the full position, the light-shielding protrusions are arranged to project inside the housing to reliably block the optical path of the optical sensor. As a result, the full state of the collected toner is detected.

In this case, even if the distribution of the collected toner deviates to a position corresponding to the outside of the frequently used latent image forming area on the latent image carrier, the float member has a surface outside the frequently used latent image forming area. Since it does not, the float member does not rise directly following the biased toner,
Moreover, the float member is not inclined due to the uneven toner distribution. Further, since the float member has a size which is more than half of the maximum latent image forming area, even if the distribution of the collected toner corresponding to the frequently used latent image forming area is locally biased, The locally biased toner portion due to its own weight is dispersed in the periphery. Therefore, the float member follows only the collected toner corresponding to the frequently used latent image forming area and ascends while maintaining a substantially parallel state.

[Embodiment] Hereinafter, the present invention will be described in detail based on an embodiment shown in the accompanying drawings.

FIGS. 1 and 2 show a collected toner full detection device used in a so-called center registration type copying machine.

In the figure, the toner collecting device comprises a photosensitive drum 1 serving as a latent image carrier, a cleaning blade 2 serving as a cleaning unit, a toner receiving member 3 and a toner conveying member 4 to form one unit. In the unit case C, the toner receiving member 3 is arranged in the vicinity of the toner introducing portion 5c of the toner recovery box 5, and the photosensitive drum 1, the cleaning blade 2 and the toner conveying member 4 are integrally provided. It is a thing. Further, the toner conveying member 4 is formed in a substantially quadrangular shape in cross section and rotated in the arrow direction. In FIG. 1, reference numeral 8 is a partition wall vertically extending from the upper wall of the unit case C to partition the toner recovery box 5 region, and 9
Is a plate-shaped toner scraping member whose one end is fixed to the partition wall 8 and elastically contacts the toner transport member 4.

Further, the full-collection-toner detecting device attached to the toner collecting device is provided with a transparent or semitransparent housing 11 bulging upward at an opening 10 formed in the upper part of the toner collecting box 5, and the housing 11. Corresponding to the optical sensor 12 in which the light emitting element 12a and the light receiving element 12b are disposed on both sides of the optical element 12 so as to face each other, the float member 20 floatably disposed in the toner recovery box 5, and the housing 11 section. And a light-shielding protrusion that is erected on the float member 20.
It has 30 and.

In this embodiment, the float member 20 is
As shown in FIGS. 4 and 5, the float member 20 is formed of ABS resin or the like into a substantially rectangular plate shape, and the float member 20 has a frequency of use with the axial center position 50 of the photosensitive drum 1 as a symmetry line. It is arranged in a range corresponding to a high latent image forming area (for example, an area corresponding to the JIS standard A4 size paper size) M. Specifically, the longitudinal dimension (the dimension along the axial direction of the photosensitive drum) l ₁ of the float member 20 is the maximum latent image forming area (for example, JIS standard A3 plate size Area) The width dimension of the float member 20 (dimension along the direction orthogonal to the axial direction of the photosensitive drum 1) l ₂ is set to about 70% of M _max , and is substantially equal to the width dimension 1 of the toner collecting box 5. Correspondingly set. Both sides in the longitudinal direction of the float member 20 are suspended and supported on the upper part of the toner recovery box 5 via flexible sheets 21 (specifically, 21a and 21b), and the float member 20 is flexible. It is designed to move up and down together with the seat 21. In this embodiment, the flexible sheet 21 is made of, for example, a polyethylene terephthalate film or polypropylene film having a thickness of 25 μm, has bent portions 22 and 23 at the upper and lower ends thereof, and is provided on the inner wall of the upper portion of the toner recovery box 5. One bent part
22 is fixed by double-sided tape or the like, and the other bent portion 23 is fixedly attached to both ends in the longitudinal direction of the float member 20 by double-sided tape or the like.

The light-shielding protruding piece 30 is made of, for example, an impermeable black member such as ABS resin, and is provided corresponding to the axial center position 50 of the photosensitive drum 1, while the length dimension thereof is recovered. The position is set so that the optical path of the optical sensor 12 is reliably blocked with the position of the float member 20 as a reference surface when the toner is full in a flat state.

Next, the operation of the collected toner full detection device according to this embodiment will be described.

Now, as shown in FIGS. 1 and 2, if the residual toner on the photosensitive drum 1 is scraped off by the cleaning blade 2 and falls on the toner receiving member 3, the toner on the toner receiving member 3 is discharged. Are collected in the toner collecting box 5 via the toner conveying member 4. At this time, the toner in the toner recovery box 5 gradually rises, and after a certain amount of time has passed, the toner reaches the lower surface of the float member 20. After that, when the toner further rises, the float member 20 rises following this as shown by the phantom line in FIGS. 1 and 2, and when the toner becomes full, the float member 20 Twenty stops its movement. In this state, the light shielding protrusion 30 on the float member 20,
The optical path of the optical sensor 12 is interrupted because it is arranged so as to plunge into the housing 11. Then the optical sensor
Since the output of 12 changes from high level to low level, the optical sensor 12 detects the full state of toner.

In such a detecting operation process, when the copying operation is performed on a copy paper (A4 size) of a size which is frequently used and is smaller than the maximum size copy paper (A3 size), the substantial amount on the photosensitive drum 1 is substantially reduced. The latent image forming area M is narrower than the maximum latent image forming area M _max. However, in a type without an erase device for erasing an unnecessary latent image on the photosensitive drum 1, a document cover (not shown) is used. If the copying operation is performed without closing, the area outside the substantial latent image forming area M is developed as a solid black image, and the residual toner corresponding to the solid black image is collected in the toner collecting box 5. Occur.

In this state, the amount of toner collected outside the substantial latent image forming region M is larger than the amount of toner collected in the substantial latent image forming region M, so that the toner is collected outside the substantial latent image forming region M. Although the toner T ′ reaches the free hanging position of the float member 20 earlier, the float member 20 is not arranged facing the outer side of the substantial latent image forming area M, and thus the recovered toner is obtained. The float member 20 is not directly raised by T'and the float member 20 is not inclined. Further, even if the distribution of the collected toner T corresponding to the substantial latent image forming area M is locally biased, the float member 20 functions to disperse the locally biased toner portion due to its own weight. Accordingly, the float member 20 follows only the collected toner T corresponding to the substantial latent image forming area M and sequentially rises substantially in parallel, and the full state of the collected toner in the substantial latent image forming area M is Accurately detected.

Further, in this embodiment, even if the floating toner in the toner collecting box 5 adheres to the inner wall surface of the housing 11, if the toner full detection signal in the optical sensor 12 is preset to an absolute zero level. The situation in which the optical sensor 12 erroneously detects the toner full state due to the presence of the adhered toner is effectively avoided.

Further, in this embodiment, if the full amount of the collected toner is set in advance corresponding to the life of the photosensitive drum 1, it becomes possible to display the replacement of the unit based on the full toner detection signal. In this case, it is not necessary to individually maintain and inspect the toner collecting device, the cleaning unit, the photosensitive drum 1, and the like, and the maintenance and inspection work of parts such as a copying machine is simplified.

Furthermore, in this embodiment, since the float member 20 is hung and supported by the flexible sheets 21 on both sides in the longitudinal direction, the flexible sheet 21 transfers the collected toner onto the float member 20. It also functions as a seal member to prevent riding. If both sides in the width direction of the float member 20 are suspended and supported by the flexible sheets as described above, the sealing property of the width direction peripheral edge of the float member 20 can be further improved. In this case, even if the widthwise dimension of the float member 20 is set to be somewhat short, the toner collected from the both widthwise end edges of the float member 20 is collected.
The situation of climbing up is effectively avoided.

In this embodiment, a collected toner full detection device used in a center registration type copying machine is shown. For example, in a corner registration type copying machine, as shown in FIG. A latent image forming area that is frequently used and is partitioned based on a positioning reference line 51 located near the axial end of the drum 1 (for example,
The float member 20 may be arranged corresponding to the area M of the A4 size paper. At this time, the disposition position of the light shielding protrusion 30 may be generally at the center of the float member 20, but, for example, when the frequency of use of the latent image forming area M'corresponding to the B5 plate size is relatively high, the Since the collected toner in the image forming areas M and M ′ is dealt with intensively, the float member
A light-shielding protrusion near the positioning reference line 51 with respect to the approximate center of 20.
It is desirable to set up 30. Further, in this embodiment, since an extremely thin film is used as the flexible sheet 21, it becomes difficult to handle when suspending the float member 20, but as shown by a phantom line in FIG. If the flexible sheet 21 is made of a polyethylene terephthalate film or a polypropylene film having a thickness of about 50 μm, and a cut 28 is provided in a part of the flexible sheet 21, it becomes easy to handle when suspending the float member 20, and
It is possible to sufficiently secure the bending deformation margin of the flexible sheet 21. Further, in the above embodiment, the float member
Although 20 is hung and supported, it is not limited to this. For example, as shown in FIG. 6, a pair of support pieces 25 made of synthetic resin or the like are provided on the inner wall of the upper portion of the toner collection box 5 (specifically, 25a, 25b) project downward and
The tip end portions of 25 may be bent inward, and the float member 20 may be placed on the bent portions 26.

[Advantages of the Invention] As described above, according to the full-collection-toner detection device of the present invention, even if the amount of collected toner outside the frequently used latent image forming area is large, the toner distribution Of the toner corresponding to the latent image forming area because the collected toner corresponding to the frequently used latent image forming area is made to follow without directly raising the float member. The full state can be detected accurately.

Further, since the dimension of the float member along the axial direction of the latent image carrier is set to be more than half of the maximum latent image forming area, even if the toner distribution is locally biased, the toner distribution is biased. Can be dispersed around the float member by its own weight, and the inclination of the rising posture of the float member can be effectively prevented.

Further, according to this invention, since the flat plate-shaped float member is merely added to the conventional structure, there is no concern that the apparatus cost unnecessarily increases.

[Brief description of drawings]

FIG. 1 is a sectional explanatory view showing an embodiment of a full-collection detector for collected toner according to the present invention, FIG. 2 is a sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a float member according to the embodiment. FIG. 4 is a perspective view of a main part showing a support structure, FIG. 4 is an explanatory view showing a positional relationship of the float members according to the embodiment, FIG. 5 is an explanatory view showing a modified example of the positions of the float members, and FIG. FIG. 7 is an explanatory view showing a modified example of the support structure of the float member, and FIG. 7 is a sectional explanatory view showing an example of a conventional collected toner full detection device. [Explanation of Codes] (M) …… Latent image forming area that is frequently used (M ′) …… Maximum latent image forming area (1) …… Photosensitive drum (latent image carrier) (2) …… Cleaning blade ( Cleaning means) (5) Toner collection box (11) Housing (12) Optical sensor (12a) Light emitting element (12b) Light receiving element (20) Float member, ( 21) …… Flexible sheet (30) …… Shade piece

Claims (4)

[Scope of utility model registration request] 1. A full-collection-toner detection device attached to a toner recovery device for recovering residual toner on a latent image carrier cleaned by a cleaning means in a toner recovery box. An optical sensor consisting of a light emitting portion and a light receiving portion is arranged at the top of the box, while a flat plate-like float member is floatably provided in the toner collecting box, and the float member faces the optical sensor. A non-transmissive light-shielding protrusion that extends upward corresponding to the gap is provided, and when the float member rises according to the amount of collected toner, the light-shielding protrusion blocks the optical path of the optical sensor to collect the toner. Is a device for detecting the full state of the collected toner, in which the dimension of the float member along the axial direction of the latent image carrier is more than half of the maximum latent image forming area. Is set within a latent image forming area that is narrower than the maximum latent image forming area and is frequently used, and the float member is placed at a position substantially corresponding to the frequently used latent image forming area along the axial direction of the latent image carrier. An apparatus for detecting the fullness of collected toner, which is characterized by being arranged. 2. A utility model registration claim characterized in that the widthwise dimension of the float member along the direction orthogonal to the axial direction of the latent image carrier substantially coincides with the corresponding dimension of the toner recovery box. The collected toner full detection device according to item 1. 3. A device for detecting fullness of collected toner according to claim 1, wherein the float member is suspended and supported on the upper part of the toner collection box through a flexible sheet. . 4. A practical use characterized in that a toner recovery device is a unit type with a cleaning device and a latent image carrier, and the replacement of the unit is indicated based on a full detection signal of the recovered toner. The device for detecting the fullness of collected toner according to claim 1 of the new model registration.