JPH01158474A - Fullness detecting device for waste toner recovery mechanism and waste toner recovery container of cleaning device - Google Patents

Abstract

PURPOSE:To detect a specific fullness state with high accuracy at all times by making a detecting means abut elastically on a cleaning part which has a member to be detected movably or a member coupled with it in one body. CONSTITUTION:The detecting member 15 is freed after a cleaning unit 20 is mounted at a specific position, and then the lower end of the detecting member 15 abuts elastically on the peak surface of a cleaning unit case 14 with the energizing force of a leaf spring 16. Therefore, the position relation between a position corresponding to the toner recovery amount of the member 13 to be detected which is supported pivotally on a shaft fixed to the cleaning unit case 14 and the optical axis 15a of the detecting member 15 is held highly accurate regardless of variation in the size and assembly accuracy among parts. Consequently, when the waste toner recovery part in the cleaning unit case 14 become full, the member 13 to be detected accurately operates the detecting member 15.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recovery mechanism for removing and recovering toner remaining on a photoreceptor after transfer of an electrostatic recording device using a cleaning means, and a fullness detection device for a recovery container.

In recent years, electrostatic recording devices such as electrophotographic copying machines, electrostatic printers, and facsimile machines have been equipped with an integrated system for cleaning the toner remaining on the photoreceptor after transfer and collecting the toner removed by this cleaning. , which can be attached to and detached from the main body of the device,
Devices that allow users to easily replace or dispose of waste toner have come into wide use. Therefore, it is necessary to provide a means for detecting whether the waste toner collection container is full.

FIG. 7 is a diagram showing an example of a configuration near the cleaning unit of an electrostatic recording apparatus including a cleaning unit having a waste toner collection container fullness detection device. In the figure, around the photoreceptor drum 1, there is a charger 2, an exposure position 3. A developing roller 4, a transfer charger 6, and a cleaning unit 20 are provided, and the toner image formed on the photoreceptor drum 1 by a predetermined process is transferred to the transfer paper 5 by the transfer charger 6, and after the transfer, the toner image is transferred to the photoreceptor 1. The toner remaining on the top is cleaned and collected by the cleaning unit 20.

The cleaning unit 20 includes a cleaning unit case 14 and a holding member 8 on the outer surface of the cleaning unit case 14 on the photosensitive drum 1 side.
A cleaning blade 7 whose tip is held so as to be in pressure contact with the photoreceptor drum 1 via a cleaning blade 7; 1 having a collection member 9 with a rectangular cross section extending over approximately the entire width of the casing for collecting waste toner in a waste toner collection section; and a scraper 10 for scraping off toner from the collection member.
At the top of the collection section, there is a shaft 13a that is pushed up by the upper surface of the collected toner pile and is fixed to the unit case 14.
A detected member 13 is provided which rotates in the direction of the arrow about the center, and its upper portion protrudes through a slit 14a provided in the top plate of the unit case 14.

On the other hand, a cleaning unit 2 is installed in the machine frame 17 of the main body of the apparatus.
A fullness detection member 15 configured as a photointerrupter is fixed opposite to the top surface of the toner recovery container 1 at a position where the detection target member 13 is activated at the position occupied when the toner collection container is full. In order to ensure that the accumulation of toner pushes up the pressure-receiving part of the detection member 13 and to prevent the toner from going around from the pressure-reception part upwards, a sheet-like sheet is attached to the frame 11 fixed to the cleaning unit at the bottom of the detection member. It is covered with rubber fi12.

Therefore, the residual toner on the photoreceptor 1 that has been scraped off by the cleaning blade 7 is conveyed to the waste toner collection container by the collection member 9, and the toner adhering to the collection member is scraped off by the scraper 10 and placed inside the collection container. When the toner reaches a full state, the detection target member 13 is pushed up by the accumulation of waste toner, and in a predetermined full state, the detection target member 13 activates the fullness detection member 15.

By the way, the cleaning unit 20 is positioned in the frame of the main body of the apparatus by reference bins (not shown) provided on both sides of the unit case 14, and is detachably mounted thereon. In that case, it is necessary to provide a considerable margin for the fitting part of the mounting part so that it can be smoothly attached and detached, and taking into consideration that there are variations in the dimensional accuracy and mounting position accuracy of the parts, the cleaning unit 20 and the detection member 15 A certain amount of space is provided between the two and the two are kept in a non-contact state.

Therefore, the position W relationship between the cleaning unit 20 and the detection member 15 changes due to variations in the dimensions of the parts and the accuracy of assembly, resulting in a difference in the detection capacity for full detection. In the example of a cleaning unit of a copying machine, experiments show that
A difference of 11 IIm results in a difference in toner amount of 20 gf (approximately 2,000 sheets of A4 size 6% image chart). If it is detected too early, the frequency of replacing the waste toner collection unit or discharging waste toner will increase; on the other hand, if the detection is delayed, toner will condense in the collection container and the torque of the collection shaft will increase. , causing jitter.

Variations in the positional relationship between the cleaning unit and the detection member are particularly important because the main body of the device is divided into two parts, upper and lower, which are pivoted to each other at one end, and the upper unit is flipped open and the unit including the cleaning unit is guided through the opening. This is a problem with jump-open type recording devices that can be attached and detached along the same line.

FIGS. 8 and 9 are diagrams showing an example of this type of electrophotographic copying machine. In this device, the device main body 17 is divided into an upper unit 17a and a lower unit 17b, which are pivoted to each other at the left end in the figure, and the right side is opened wide as shown in FIG. 5 for maintenance, inspection, and replacement of components. It is now possible to do this. The cleaning unit 20 constitutes the photoreceptor unit 18 together with the belt-shaped photoreceptor, and the guide rail 19, which has one end pivotally supported by the upper unit 17'a and is rotatable in the directions of arrows B and B', is tilted in the direction of arrow B. Insert the guide portions 18a provided on the outer surfaces of both side plates of the photoreceptor unit 18 into it in the direction of arrow C, lift it in the direction of B' and fix it to the upper unit 17a of the main body, so that it is in the state shown in FIG. set. A photointerrupter 15 is fixed to the upper unit 17a, and becomes operable by the detected member 13 provided in the cleaning unit 20. In the recording apparatus having this configuration, it is difficult to maintain an accurate positional relationship between the detection member 15 and the detected member 13 due to variations in the dimensions of the components and variations during assembly.

In addition to the above-mentioned inaccurate positional relationship between the detection member and the detected member, the cause of the error in the fullness detection timing of the toner collection unit is
There is non-uniformity in the longitudinal distribution of the amount of toner collected in the toner collection section. Since the detection member is provided at one location in the longitudinal direction, if the amount of toner collected in that area of the toner collection section is small, the full detection time will be delayed from the actual time.
If the amount of toner collected in that area is larger than in other areas, the full detection time will be earlier than the actual time.

Non-uniformity in the longitudinal direction of the amount of collected toner can be caused by uneven image ratio of the original image, toner adhering to the photoconductor to the extent that it is not visible on a partial copy, or outside the original area when exposed with the original pressure plate open. This can occur due to various reasons, such as the formation of solid black areas on images, copying of small originals, etc.

If the toner collection amount becomes excessively uneven in the longitudinal direction, the toner filling density will increase partially before fullness is detected, causing damage to the collection means due to overload on the collection member, especially if the filling density at the ends increases. Problems such as toner leaking from the edges may occur.7 If the full detection section is filled with a large amount of toner, a full detection signal will be issued prematurely, but failure of the collection member or toner leakage due to overload will not occur. do not have.

The present invention solves the above-mentioned error in the fullness detection timing of the conventional recording device that detects the fullness of the waste toner collection container by detecting the displacement of the detected member due to the amount of collected toner with the detection member. In view of the actual situation, our first challenge is to provide a fullness detection device that can always detect a predetermined fullness state with high accuracy even if there are variations in the dimensional accuracy and assembly accuracy of parts. A second object of the present invention is to provide a waste toner collection mechanism that prevents the toner from shifting to a portion other than the full detection section even when the amount of toner is uneven in the longitudinal direction.

In order to solve the above-mentioned first problem, the first invention provides a first invention in which the detection means provided in the main body of the apparatus is coupled to a cleaning section movably having a member to be detected, or to a fishing rod. It is characterized in that it is adapted to resiliently abut against a member that is attached.

In addition, in order to solve the above-mentioned second problem, the second invention has a collecting means that transports the toner removed by the cleaning means to the toner storage section, and rotates about its own axis to remove the toner being transported. The present invention is characterized in that means is provided for moving the detected member in the axial direction within the provided range.

The configuration of the first invention improves the dimensions and assembly accuracy of members.
Instead, the full detection member is connected to the cleaning section or to the cleaning section.
Since the positional relationship with the detected member can be accurately maintained by resiliently abutting the member connected to the fishing rod, detection errors are eliminated.

Further, according to the configuration of the second invention, the toner collected by the cleaning member is transferred to the range where the fullness detection section is provided by the rotation of the collection means, so it may be assumed that a large amount of toner is collected in other parts. Even though the fullness detection may be made earlier, various problems caused by the delay can be avoided.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a diagram showing an embodiment in which the above-described first invention is applied to the waste toner container full detection device of Cleaning UniSoto, which was previously explained with reference to FIG. 7.

Therefore, the same members are given the same reference numerals, and the explanation will focus on the differences. Figure 2 shows the detection part shown in Figure 1.
- It is a view seen in the direction shown by the line.

In the device of this embodiment, the detection member 15 configured as a photointerrupter is not directly fixed to the device frame 17, but the lower end of the detection member 15 is connected to the top surface of the cleaning unit 20 via a plate spring 16 made of stainless steel or the like. It is attached so that it is biased in the direction of contact. Cleaning unit 2
0 to a predetermined position, lift the detection member 15 upward against the elasticity of the leaf spring 16 by means not shown,
Insertion and extraction are performed without interfering with the cleaning unit 20 and the detected member 13. After the cleaning unit 20 is installed in a predetermined position, when the detection member 15 is released, the lower end of the detection member 15 resiliently contacts the top surface of the cleaning unit case 14 due to the biasing force of the leaf spring 16. The positional relationship between the optical axis 15a of the detection member 15 and the position corresponding to the amount of collected toner of the detected member 13, which is swingably supported on a shaft fixed to the cleaning unit case 14, is determined by the dimensions of the parts and the assembly accuracy. Extremely high accuracy is maintained despite variations. Therefore, when the waste toner collecting section in the cleaning unit case 14 becomes full, the detected member 13 accurately activates the detecting member 15 and warns the user with a lamp, buzzer, etc., so that excess toner can be collected. It is possible to avoid problems caused by premature replacement of the cleaning unit, premature disposal of waste toner, etc.

Note that when the present invention is applied to an apparatus in which the cleaning unit as explained in FIGS. 8 and 9 is contained inside the photoreceptor unit case and is attached to and detached from the apparatus body integrally with the photoreceptor unit, the detection member The lower end of may be brought into contact with the photoreceptor unit case.

Further, the means for elastically bringing the detection member into contact with the cleaning unit or a member connected thereto with a fishing line is not limited to a leaf spring, but may be a spring such as a coil spring, rubber, or the like.

Next, an embodiment in which the above second invention is applied to the cleaning device described in FIG. 7 will be described based on FIGS. 3 and 4. These figures show the toner collecting member 9 with a square cross section, the full detection member 13, and the cleaning unit case 14 in which the toner collecting container is formed, and other members are omitted. As is clear from these figures, the full member to be detected 13 is provided at the center of the cleaning unit case 14 in the longitudinal direction. Further, the toner collection member 9 has a square cross section as in the conventional case, and as it rotates clockwise in FIG. The point at which it is moved is not particularly different from the conventional one, but it is twisted 90' in the opposite direction from the center in the longitudinal direction to both ends. As a result, when the toner collecting member 9 is rotated clockwise in FIG. Move it closer to the center.

As a result, the toner moves to the center where the full detection target member 13 is located.

Note that in FIG. 4, reference numeral 21 is a gear for rotating the toner collection member, which meshes with a drive gear rotated by a drive source (not shown).

Since the toner collecting member 9 is twisted gently, the flexible scraper 10 can easily follow the surface of the toner collecting member 9 and scrape off the toner.

5 and 6 show an embodiment in which the toner collecting member 9a has a sheet metal shape with both ends of the cross section bent.

In this case as well, both ends are twisted 90° in opposite directions with respect to the center, and the same effect as in the embodiments shown in FIGS. 3 and 4 is achieved. The toner is dammed by a member indicated by the reference numeral 22 and collected into the toner container.

Incidentally, as a collection member for conveying the toner scraped off from the photoreceptor drum by the cleaning blade to the waste toner collection section, a square bar with a square cross section has been widely used as described above. The recovery member having this shape has four edges that push the toner forward, and has excellent features such as high conveyance efficiency and low manufacturing cost.

However, in the conventional cleaning device, the collecting member is
As shown in the figure, since the entire length of the cleaning unit is configured as one square prism, as the amount of toner in the toner collecting section increases, the edges of the collecting member rotate as they push the toner forward. The torque increases gradually, and during one rotation of the collection member, the rotational torque reaches the 11th
As shown in Figure (a), the torque fluctuates so that four peaks occur, and the output of the drive source and the strength of the drive system had to correspond to the maximum torque. Therefore, it is desirable to equalize the torque during one rotation of the recovery member as shown in FIG. 11(b).

As a countermeasure, as shown in Fig. 12, if the collection member is divided into two parts at the center in the longitudinal direction and the positions of the ridges of each square cross section are shifted by 45 degrees, the torque of one side will be maximum. On the other hand, the load on the gear at the end of the shaft is equalized over one revolution.

Also, as shown in Fig. 13, the square prism is 90° to 90° along its entire length.
Even if the shape is twisted by 180°, load fluctuations are made uniform. In this case, compared to the example shown in Figure 12, there is no concentration of stress, and with this degree of torsion, the lateral movement of the toner due to the conveying force due to the twist is not as large as on the left, and toner deviation occurs. do not.

9-1 As described above, according to the first invention, the positional relationship between the detected member and the detection member for detecting the fullness of the waste toner collection container can be accurately determined regardless of variations in member dimensions and assembly accuracy. Furthermore, according to the second aspect of the invention, even if toner is collected unevenly, fullness is detected without delay, making it possible to replace and dispose of the waste toner collection container in a timely manner. Also, since toner leakage is prevented, it is easy to handle when replacing.
It also prevents the interior of the aircraft from getting dirty.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of the first invention of the present invention, FIG. 2 is a sectional view taken along the line II-II in FIG. 1, and FIG. FIG. 4 is a sectional view thereof, FIG. 5 is a sectional view showing another embodiment of the second invention,
FIG. 6 is a perspective view of the toner collecting member, FIG. 7 is a side sectional view of a conventional waste toner collecting section, and FIGS. 8 and 9 are side sectional views of an example of a conventional jump-open type recording device, respectively. Fig. 10 is a perspective view showing an example of a conventional rectangular cross-section collection member, and Fig. 11 (
a) is a curve diagram showing the torque fluctuation during one rotation, the first
Figure 1 (b) is a curve diagram showing desirable torque fluctuations, the 12th
This figure and FIG. 13 are perspective views showing examples of the shape of the recovery member that can equalize the torque. ■... Photoreceptor, 9... Toner collection member, 10... Scraper, 13... Detected member, 14... Cleaning unit gauge, 15... Photo interrupter (detection member), 16... ...Plate spring (elastic member), 17...Device main body, 18...Photoconductor unit, 20...Cleaning unit Fig. 1 Fig. 2 Fig. 6 Fig. 7 Fig. 9 Fig. 7b

Claims (4)

[Claims] (1) A cleaning means for removing toner remaining on the photoreceptor after transfer, a collection container for storing the waste toner collected by the cleaning means, and a detection member that is displaced according to the amount of collected toner in the container. in a cleaning section that is detachable from the apparatus main body, and detects the detected member with a detection means provided in the apparatus main body to detect whether the waste toner collection container is full. A fullness detection device characterized in that the detection means elastically abuts the cleaning section or a member integrally connected thereto. (2) The means for elastically bringing the detection means into contact with the cleaning part that holds the detected member or a member integrally connected therewith is connected to the unit that holds the detection member via an elastic member. The fullness detection device according to claim 1, wherein the fullness detection device is installed. (3) A cleaning means for removing toner remaining on the photoreceptor after transfer, and a toner storage section that extends over the entire width of the photoreceptor and rotates around its own axis to remove the toner removed by the cleaning means. The cleaning device includes a collecting means for transporting the toner, a toner storage section for collecting the toner, and a detected member that is displaced according to the amount of collected toner in the toner storage section, and the detection means is provided in the main body of the device. In a toner collection mechanism of a cleaning device for an electrostatic recording device that detects whether a toner storage portion is full by detecting the fullness of the toner storage portion, the toner conveyed by rotating around its own axis is transferred to the detected member in the axial direction. A toner collection mechanism characterized in that the toner collection mechanism is provided with a means for moving the toner to a predetermined range. (4) Claim 3, wherein the means for moving the toner in the axial direction provided in the collecting means has a shape in which the collecting means is twisted around its axis.
The toner collection mechanism described in .