JPS5952275A - Electrophotographic copying device - Google Patents

Abstract

PURPOSE:To prevent a cleaning defect and to improve the life of a cleaning blade by detecting sliding contact pressure and adjusting the sliding contact pressure of the cleaning blade with an image carrier. CONSTITUTION:The turn state of a photosensitive drum as an image carrier corresponding to a load depending upon the sliding contact pressure of the blade 10 is detected through a clock pulse disk 7, a photointerrupter 9, etc. A motor 16 for sliding contact pressure adjustment is feedback controlled microcomputer, etc., on the basis of the detected pressure to adjust the sliding contact pressure of the blade 10 with the drum 5 to a specified value; the cleaning defect is prevented and unnecessary abrasion is eliminated to improve the life of the cleaning blade.

Description

[Detailed description of the invention]

(1) Technical Field The present invention relates to an electronic copying device that transfers an image on an image carrier consisting of a drum-shaped or belt-shaped image bearing member to a recording material using toner, and particularly relates to a cleaner blade for removing residual toner and an image carrier. The sliding pressure between the bodies can be detected and adjusted. (1) Prior Art In electronic copying apparatuses, cleaning means for removing toner remaining on the image carrier after transfer include a blade method, a wave method, a brush method, a magnetic brush method, and the like. Among these, those using the blade method (blade cleaning method) are cleaner blades (hereinafter referred to as blades) made of wear-resistant plate materials such as urethane rubber.
This device scrapes off the residual toner on the image carrier by sliding it in pressure contact with the image carrier, but it has a relatively simple structure, is small, has excellent cleaning properties, and has a relatively low manufacturing cost. It is commonly used because it has advantages such as less noise and toner scattering. However, with such a grade system, it is necessary to increase the sliding pressure on the image carrier to a certain extent in order to improve the cleaning effect, but as the sliding pressure increases, the life of the blade itself and the image carrier decreases. There's a problem. On the other hand, if the sliding EE (cleaner blade pressure, contact pressure) is too low, fine powder toner will not be removed and will remain on the image carrier even after cleaning, resulting in poor cleaning that will cause image defects. There is. Therefore,
In order to solve the above-mentioned problems, the sliding pressure between the image carrier and the blade must always be maintained at a predetermined appropriate pressure.
Conventional devices do not have a self-diagnosis function or adjustment function for the sliding pressure, so it is difficult to maintain the sliding pressure at an appropriate level. (II+) Purpose In view of the above-mentioned points, the present invention provides a numerical value that can be used as a guide to objectively know the cleaning performance by means of a self-diagnosis means that detects and displays the sliding pressure of the cleaner blade on the image bearing member. The sliding pressure adjustment means that can maintain the proper sliding pressure eliminates the need for sliding pressure inspection during regular maintenance work and sliding friction pressure adjustment during factory assembly, and prevents image defects. to maintain the best cleaning performance at all times.
An object of the present invention is to provide an electronic copying apparatus that can improve the lifespan of an image carrier and a grade. (IV-1) First Embodiment The present invention will now be described in detail with reference to the drawings. In general, main motors used in electronic copying machines, etc. have "speed-torque" characteristics as shown in Figure 1.
Within its practical output range, its speed decreases in proportion to the increase in torque. As described above, since there is a certain correlation between the speed and torque fluctuations of the main motor used in the device of the present invention, if a speed change of the main motor or the rotating body driven by the main motor is detected, the load fluctuation can be detected. The corresponding change in the aforementioned sliding pressure can be objectively and accurately calculated. Figure 1 shows an example of the configuration of the speed detection means of the device of the present invention,
Here, l is the main motor, (j) is the driving gear fixed to the output shaft of the main motor l, 3 is the driven gear that meshes with the driving gear 2, da is the bottle protruding from the back of the driven gear 3, and S is the binder. Driven gear 3 through
The output of the main motor l is transmitted to the photosensitive drum j via gears 2 and 3 and the binder, and rotates the photosensitive drum j in the direction indicated by the arrow. 6 is the rotating shaft of the driven gear 3, 7 is a Cronk pulse disk which is fixed to the tip of the rotating shaft B and rotates together with the photosensitive tram 5, and r is formed at equal intervals over the entire outer circumference of the Cronk pulse disk 7. The notch r is formed by dividing the circumference into 100 equal parts, for example, as shown in FIG. Reference numeral 9 denotes a photointerrupter consisting of a light emitting diode and a light receiving transistor, which is sandwiched between both end surfaces of the Cronk pulse disk 70 in a non-contact manner.
The rotational speed of the photosensitive drum j is detected via the photosensitive drum j. Driven by the main motor l, the photosensitive drum (6) j and the clock pulse disc 7 rotate together in the same direction, and the parts 11 between the notch t on the circumference of the clock pulse disc 7 and the photointerrupter 90 are successively rotated. pass. By passing through this notch t. The light-receiving transistor in the photo-interrupter 9 repeats on-off (conduction-non-conduction) operations and generates a rectangular wave as shown in FIG. Fig. 4 shows an example of the circuit configuration of an interface circuit IF inserted between the photointerrupter 9 and a device built-in microcomputer (hereinafter referred to as microcomputer) CPU, which will be described later. A noise-canting diode, C a bypass capacitor, and R/ and SE resistors. FIG. 6 shows an example of the configuration of the control means of the device of the present invention, which has the speed detection means shown in FIG. 1 and the interface circuit IF shown in FIG. Blade (cleaner blade), /no is a holding plate that holds the blade 10.

This is a blade shaft that makes the [mounting angle] variable. By rotating the blade shaft /2, the angle of the blade /θ that presses against the photosensitive drum S can be changed around the shaft 12, and the angle of the blade 10 relative to the photosensitive drum S can be changed by rotating the blade shaft /2. The sliding pressure can be adjusted. In addition, DEW Lt has a depth inch for self-diagnosis mode switching, TK has a tenth inch for setting the number of copies, and M
C is a motor control board (motor driver), and DNS is an indicator that displays the sliding pressure. Next, an example of the operation of the electronic copying apparatus of the present invention shown in FIG. 7 will be described with reference to the flowchart of FIG. First, when it is not in the self-diagnosis mode, normal copy processing operations are carried out (steps T/ and T2), but when the focus of the depth switch DSW is turned on (ON), it becomes the self-diagnosis mode (step T/), and then the numeric keypad TKO
predetermined number

[For example, 19"] is pressed, the self-diagnosis start signal S/ is supplied from the numeric keypad TK to the microcomputer cptr (step TJ). In response to the reception of this self-diagnosis start signal 8/, the microcomputer CPU sends the signal to the motor control board MC. In response, a drive signal S2 instructing to drive the main motor is sent (step Tel).Motor control board MC
In response to the reception of the drive signal 8.2, the main motor 1 is accurately rotated for a predetermined period of time (for example, 2 seconds) (step Tj). While the main motor l is rotating, the clock pulse disk 7 rotates in synchronization with it. Here, if the notch r of the clock pulse disk 7 is in the form of, for example, 100 divisions as shown in FIG. This will be obtained from the IF. The microcomputer CPU counts the number of pulses of the output signal S3 from the interface circuit IP while the main motor l is rotating (for example, for -seconds) (step T6). The number of pulses counted by the microcomputer CPU (9) The rotational speed of the original drum 5 corresponds, so the microcomputer CPU
U is the r speed [-)k” characteristic of the main motor l

[See Figure 1], the number of pulses is converted into a sliding pressure (step S7), and a numerical value indicating the resulting sliding pressure is displayed on the display DI8 via the signal St (step S7). I'
, r). Note that the display target displayed on the display DIS is not necessarily limited to the sliding pressure, but it goes without saying that the rotation speed of the photosensitive drum 50, which has a correlation with the sliding pressure, may also be displayed. As mentioned above, since the blade lθ is in contact with the photosensitive drum 5 with a predetermined pressure (sliding pressure), the main motor lθ
rotates at a predetermined number of rotations corresponding to the sliding pressure. Therefore, when the blade 10 is damaged due to expiration of its durability period, etc., the sliding pressure changes, and the rotational speed of the main motor 1 etc. changes accordingly. This change in rotational speed is confirmed by the display DIS as a change in sliding pressure, so cleaning performance can be objectively known, and the sliding pressure can be adjusted by adjusting the angle of the grade (If) 1 axis/2. It can be maintained at the appropriate pressure. In other words, the number of rotations of the main motor detected by the speed detection means is rubbed by the cleaner blade.
Since the sliding friction pressure is converted and displayed, it is possible to objectively detect the sliding friction pressure, and by comparing this with a predetermined appropriate pressure, the sliding friction pressure adjustment work is facilitated. Since a guideline for replacement can be obtained, cleaning abnormalities can be prevented from occurring. Also, if the copying machine is operated for a long period of time with the blade/θ being defective, toner may scatter inside the machine or the band 1! Is there any possibility of line contamination?1
In this example, since a defective state of the blade /θ can be detected early, it is possible to prevent the above-mentioned negative effects from expanding. (Iv-1 Second Embodiment FIG. 1 shows another example of the structure of the cleaner section of the electronic copying apparatus of the present invention, where 73 is a plate) - A driven gear fixed to M No. 2, /4t is a driven gear 13 /S is the motor output shaft with the drive gear fixed to one end;
This is a motor for automatic adjustment of sliding friction pressure having a 6Gilt motor output shaft/S. This motor/6 is controlled by the microcomputer CPU in the self-diagnosis mode by the motor driver MCJ (described later).
The motor output shaft 15. rotates in the forward or reverse direction by drive control through the motor output shaft 15. A pair of gears 13 and 1
The angle of the blade 10 is increased/decreased via the I11 blade shaft 12 and the holding plate//, and the aforementioned sliding portion pressure is automatically adjusted to a predetermined appropriate level. A roller 17 prevents a portion of the residual toner that was pressed against the photosensitive drum 5 and removed from the photosensitive drum s by the blade lθ from sliding off the photosensitive drum j before reaching the conveyance area of the screw/I. To prevent. /9 is a scrubber for removing toner adhering to the roller 17; 〃 and n are sealing members l that prevent residual toner from scattering.
A pipe communicates with a recovered toner cassette (not shown), and the remaining toner removed from the photosensitive drum j by the blade /θ is transferred to the recovered toner cassette via the screw /g and pipe n. 21 is a photosensitive drum depending on the grade/θ! A web is used to completely remove the fine powder toner that has not been removed from above from the top of the photosensitive drum 5, 25 is the unused web, bu is the used web, and the shaft 1 is interlocked with the photosensitive drum S. When the web 24I rotates in the direction of arrow B, the web 24I is unwound from the roll-shaped unused web B which is supported by a bearing d,
Roll it up onto the used web. 〃 is a pressure roller made of an elastic material that presses the wound web cog onto the photosensitive drum S;
3θ is a pressure roller shaft that supports the roller, and 31 is a bank unroller that presses the pressure roller to ensure the feeding of the web 2. These web mechanisms 21 to 3 are used to control the above-mentioned blade mechanism 70. In steps 23 to 23, the remaining toner that could not be scraped off is completely removed from the photosensitive drum j. 32 is the above-mentioned blade mechanism including blade/θ/θ~n
The first unit 33 is a second unit equipped with the above-mentioned web mechanisms 2'l to 31 including the web (/3) 2, and both units 32 and 33 are mounted on a connecting shaft 3 and a pair of springs. The hooks 35 and 3g are separably connected via a spring n stretched between the spring hooks. FIG. 9 shows an example of the configuration of the control means of the device of the present invention having the crease section shown in FIG. This is the first motor driver that rotates the motor accurately, and corresponds to the main motor control board MC of the previous embodiment shown in FIG. 7. m, MCJ is a second motor driver that controls the drive of the motor 16 for automatic sliding friction adjustment, and the motor 16 is controlled in accordance with the drive signal SS from the microcomputer CPU.
Rotate in the forward or reverse direction to automatically adjust the sliding pressure. The rest of the structure is almost the same as the previous embodiment shown in FIG. Next, the operation of this embodiment shown in FIG. 9 will be explained with reference to the flowchart shown in FIG. 1θ. Note that the control procedure up to (/4I) steps T/-T and r is almost the same as the control procedure of the previous embodiment shown in FIG. 7, so detailed explanation thereof will be omitted. In this embodiment, after displaying the sliding pressure (blade [E) calculated in step T7 on the display device DNS] (step Ti
)%The microcomputer CPU determines whether the displayed sliding pressure (hereinafter referred to as 1 display pressure) matches the predetermined appropriate sliding pressure (hereinafter referred to as appropriate pressure). (Step T9). If the sliding pressure and the appropriate pressure match, an affirmative determination is made and the process returns to the first step T/; however, if the sliding pressure and the appropriate pressure do not match, a negative determination is made and the first step T/ is determined. Proceeding to step T10, the microcomputer CPU determines whether the displayed pressure is greater than the appropriate pressure or not. If the displayed pressure is greater than the sliding friction pressure, an affirmative determination is made and the process proceeds to step T//, where the second motor driver MC2 drives the motor in the direction of decreasing the sliding friction pressure in accordance with the drive signal 8j supplied from the microcomputer CPU. 16 by a predetermined angle, the process returns to step TII, and the series of operations from steps TF to Tll described above are repeated until an affirmative determination is made in step T9 that the displayed pressure matches the appropriate pressure. On the other hand, if the percentage display pressure is also small, a negative determination is made in step T10 and the process proceeds to step T/j.
The microcomputer CPU sends a drive signal S5 that instructs the second motor driver MC2 to slightly rotate the motor 16 by a predetermined angle in a direction that increases the sliding pressure.
After slightly rotating by a predetermined angle, return to step 'I'4 (again) and repeat the series of operations of steps TII to TIO and TI2 described above until the displayed pressure matches the appropriate pressure.The above series of control operations When the appropriate pressure is displayed on the display DI8, the automatic adjustment of the rubbing pressure is completed, and when the depth switch D8W is turned off, the process moves to step T2 and the normal copying operation is resumed.In this way, in this example, Since the sliding pressure can be automatically adjusted to the appropriate pressure, there is no need to adjust the sliding pressure during factory assembly or blade replacement, and it also eliminates cleaning defects and improves the quality of the photosensitive drum S and blade 10. The effect is that the durability can be increased. (IV-3) Third Embodiment Figure 1/Fig. Even when R is on during the copying operation, the sliding pressure (cleaner blade pressure) can be automatically adjusted to the appropriate pressure.Here, the F/V adjusts the output signal of the interface IP according to its frequency. Frequency-voltage conversion circuit that converts voltage to voltage (F-V conversion circuit)
, SRV is a general servo circuit that controls the rotation angle of the sliding pressure adjustment motor 16 via the motor driver MD based on the differential pressure between the output voltage of the conversion circuit layer and the reference tE. Since the main motor l is rotating during the copying operation, the clock pulse disk 7 connected to the photosensitive drum S is rotated as the main motor l rotates, and the rotation of the photosensitive drum S is controlled from the interface circuit IF regardless of the self-diagnosis mode. A clock pulse corresponding to the speed can be generated at all times. This clock pulse is converted into a voltage by the conversion circuit F/V, and the converted voltage is supplied to the servo circuit SRV. The servo circuit SRV compares the input voltage supplied from the conversion circuit F/V with a reference voltage corresponding to the appropriate sliding friction pressure, supplies a drive signal to the motor driver MD according to the voltage difference, and performs the sliding friction. The pressure adjustment motor/A is rotated in the forward or reverse direction, and feedback control is always performed so that the sliding pressure becomes a predetermined appropriate pressure. In this way, in this example, servo control is always performed so that the sliding pressure is at the appropriate pressure, so there is no need for manual sliding pressure adjustment or self-diagnosis mode switching instructions, making maintenance management easier. This makes it extremely easy to clean the photosensitive drum S and the blade lθ, and has the effect of reliably improving the durability of the photosensitive drum S and the blade lθ and preventing poor cleaning. In each of the above-described embodiments, the clock pulse disk 7 is attached to the photosensitive drum shaft B, but the disk 7 may of course be attached to any rotating shaft driven by the main motor I. It is. (v) Effects As explained above, according to the present invention, there is a means for detecting the sliding IIE (contact pressure) of the cleaner blade on the image bearing member, and a means for detecting the sliding friction IIE (contact pressure) based on the detected value obtained by the means. Since a means for adjusting the pressure to an appropriate level is provided, poor cleaning can be prevented, images can be kept in the best condition, and the lifespan of the image carrier and blade can be improved. Also,
According to the present invention, there is no need to perform a sliding pressure inspection or the like during periodic safety management work, thereby improving serviceability.

[Brief explanation of drawings]

FIG. 1 is a characteristic diagram showing an example of the relationship between the speed and torque of the main motor used in the device of the present invention, FIG. Figure 3 is an enlarged front view showing in detail the shape of the clock pulse disk in Figure 1, Figure 1 is a circuit diagram showing an example of the circuit configuration of the interface inserted between the 7-bit interrupter in Figure 2 and the microcontroller, and Figure 5. The figure is a signal waveform diagram showing the waveform of the output signal of the circuit in Figure q.
Figure 6 is a block diagram showing an example of the configuration of the control means of the device of the present invention in Figure 2, and Figure 7 shows an example of the operation of the control means in Figure 6. Figure 70-Theyat is a sectional view showing the configuration of a cleaning device according to another embodiment of the present invention, Figure 9 is a block diagram showing the configuration of a control means according to another embodiment of the present invention, and Figure 70 is a cross-sectional view showing the configuration of a cleaning device according to another embodiment of the present invention. 9 is a flowchart showing an example of the operation of the control means, and FIG. 1 is a block diagram showing the configuration of the control means according to still another embodiment of the present invention. l...Main motor;・Gear, G...pin, S...photosensitive drum (photosensitive member, image carrier), 6...rotation shaft (photosensitive drum rotation axis), 7...clock pulse disk. Notch. 9...Photo interrupter, /θ...Grade (cleaner blade), /l...
Holding plate, /2...Blade shaft, /3. /'l...Gear. 15...Motor output shaft, 16...Sliding ratio adjustment motor, /7...Roller (cleaner roller), 7g...Screw, /9...Scraper, ~n...Seal Element. n...pipe, 2g...web, B...unused web, 26...used web, knife...rotating shaft, d...bearing, knife...pressing roller, ( 2/) 3θ...pressure roller shaft, 31...bank up roller, 32...first unit, 33...second unit, evaluation...connection shaft, 35.3t...spring hook , I...spring. IF...Interface circuit. CPU...Microcomputer [Microcomputer] 1DS
W...Menpusuinteki, TK...Numeric keypad, DIR...Display, MC, MC/...Main motor control board (first motor driver), MC, 2, MD...For sliding friction pressure adjustment Motor control board (first motor driver), F/V...frequency-voltage conversion circuit (F-V conversion circuit)
, 5aV-- Servo circuit. (22) Figure 2 Vcc JP-A-59-52275 (10)

Claims (1)

[Scope of Claims] 1) A cleaning means for removing transfer residual toner remaining on an image bearing member after the transfer of a toner image by rubbing against the image bearing member, and a cleaning means that removes transferred residual toner remaining on the image bearing member after the transfer of the toner image, and a cleaning means that removes transferred residual toner remaining on the image bearing member after the transfer of the toner image, and a cleaning means that removes the transferred residual toner remaining on the image bearing member by rubbing against the image bearing member, and a cleaning means that removes the transfer residual toner remaining on the image bearing member after the transfer of the toner image, and a cleaning means that removes the transferred residual toner remaining on the image bearing member by rubbing against the image bearing member, and a cleaning means that removes the transfer residual toner remaining on the image bearing member after the transfer of the toner image, and a cleaning means that removes the transfer residual toner remaining on the image bearing member after the transfer of the toner image. An electronic copying apparatus comprising an image carrier driving means for changing the speed of the image carrier, a detection means for detecting the speed of the image carrier, and a speed detected by the detection means or conversion based on the speed. 1. An electronic copying apparatus comprising: an adjustment means for adjusting the sliding pressure by comparing the sliding pressure with a predetermined appropriate speed or appropriate sliding pressure. 2. An electronic copying apparatus according to claim 1, further comprising a mode in which each of the means operates independently of the copying operation, and a selection means for selecting the mode. 3) An electronic copying apparatus according to claim 1, wherein the adjusting means is a means for automatically adjusting the sliding pressure to the appropriate sliding pressure. 4. An electronic copying apparatus according to claim 1, wherein the adjustment of the sliding pressure is automatically performed even during a copying operation. 5) Claim 1 7-1 The device according to the present invention is characterized by comprising display means for displaying the speed detected by the detection means or the sliding friction pressure converted based on the speed. Electronic copying equipment.