JPH07225513A - Detection of residual toner and device therefor - Google Patents

Abstract

PURPOSE:To provide a residual toner detection device capable of surely performing the detection of the residual toner level in each rotating toner cartridge using only one set of sensor without increasing a cost by providing the detection means which does not move due to the rotation of the developing device. CONSTITUTION:In the cylindrical case 2, the developing unit communicated with toner cartridges 1 respectively containing the toner is housed inside the cylindrical case 2 and rotatably supported around the rotary shaft X. Then, the developing unit for the color corresponding to the latent image formed on the latent image carrier is stopped at the developing position and the latent image is made visual as the toner image. The detection means 3 is fixed to the fixed member of the image forming device main body in the state of straddling over the edge part of the respective cartridges 1. Moreover, the state of the change of the toner level by the rotation in the toner cartridge 1 is detected as the necessary information for grasping a correct residual amount of the toner, by the detection means 3 disposed at the fixed position in immovable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner remaining amount detecting method and apparatus applied to an electrophotographic type and electrostatic recording type image forming apparatus using a rotary developing device.

[0002]

2. Description of the Related Art A rotatably supported shaft is supported.
A plurality of developing devices each containing a predetermined powder developer,
In order to supply toner to the developing device, a toner cartridge provided corresponding to each developing device is provided, and the plurality of developing devices are rotated together with the toner cartridges.
There is a rotary type developing device which brings a predetermined developing device to a developing position facing the latent image carrier and visualizes the electrostatic latent image formed on the latent image carrier as a toner image by the developing device. .

An apparatus for detecting a toner remaining amount level by transmitted light in a monochromatic image forming apparatus using an electrophotographic system is one having a plurality of sensors, for example,
The technique disclosed in Japanese Patent Laid-Open No. 61-180226 is known.

Further, a device provided with a cleaning member for preventing erroneous detection due to the toner attached to the portion corresponding to the remaining amount detecting portion, for example, the technique disclosed in Japanese Patent Laid-Open No. Sho 63-2087, instantaneous light emission. As a technique for increasing the strength, for example, the technique disclosed in Japanese Patent Application Laid-Open No. 2-114281 is known.

[0005]

When the conventional single-color toner remaining amount detecting device as described above is applied to a full-color image forming apparatus equipped with a rotary developing device, a problem arises in that the cleaning member remains. In the method of providing the amount detection unit, when the toner storage unit to be detected is a disposable toner cartridge, the cost is increased.

Further, even if it is instantaneous, when the light emission intensity is increased, the light emitting element is still burdened and the life may be shortened.

Therefore, according to the present invention, the detection of the remaining toner level of the electrophotographic full-color image forming apparatus equipped with the rotary developing device that rotates together with the disposable toner cartridge does not use a plurality of sensors as in the prior art. In addition, it is an object of the present invention to provide a toner remaining amount detecting device which surely performs with only one set of sensors without increasing the cost.

[0008]

In order to achieve the above object, the present invention has the following constitution.

(1). A plurality of developing devices that are rotatably supported around a rotating shaft and each store a predetermined powder developer, and a toner cartridge provided corresponding to each developing device for supplying toner to the developing devices. And rotating the plurality of developing units together with the toner cartridges to bring a predetermined developing unit to a developing position facing the latent image carrier, and the electrostatic latent image formed on the latent image carrier by the developing unit. In a rotary developing device that visualizes a latent image as a toner image, the remaining amount level of toner in each rotating toner cartridge is detected by a single optical system that does not move due to rotation of the rotary developing device. By means of the means, the toner remaining amount detection device detects the cartridge in a non-contact manner, and the detection is performed during rotation (claim 1).

(2). In (1), when it is detected that the surface of the toner is lower than a predetermined height a plurality of times in succession, an accurate detection mode for accurately detecting the remaining amount is entered. 2).

(3). In (1) or (2), it is decided to enter the accurate detection mode according to the user's designation (claim 3).

(4). In (1), (2) or (3), the remaining amount of toner in the toner cartridge is determined using position data that changes due to driving of the rotary developing device (claim 4).

(5). In (2) or (3), there is provided means for notifying the user that the accurate detection mode has been entered (claim 5).

(6). In the accurate detection mode of (2) or (3), the drive motor that rotates the developing device so that the plurality of developing devices are located at the predetermined developing positions is repeatedly vibrated in small increments in the normal developing direction and the opposite direction. (Claim 6).

(7). In the accurate detection mode of (2) or (3), a mechanism for hitting the toner cartridge is provided outside the toner cartridge (claim 7).

(8). In the accurate detection modes of (2) to (7), the detection is performed after a lapse of a fixed time after the vibration and the beating operation of the drive motor are stopped (claim 8).

(9). In (1) to (8), 1
It has been decided that detection is performed a plurality of times for one toner cartridge (claim 9).

[0018]

The change state of the toner level in the toner cartridge due to the rotation can be detected as information necessary for accurately grasping the remaining amount of toner by the detection means fixedly provided at a fixed position.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the remaining amount of toner is determined by utilizing position data that changes with the driving of a rotary developing device, more specifically, the inclination angle information of a toner cartridge. That is,
The detection means for detecting the presence / absence of toner is fixedly fixed to an appropriate member and detected while the developing device is rotating. The detection during rotation is not very accurate, but it has an advantage that the printing speed is not reduced as compared with the case where detection is performed by stopping.

When the toner cartridge rotates together with the developing device and passes through the detecting means, if the absence of toner is detected, the remaining amount of toner in the toner cartridge is determined from the inclination angle at that time.

As described above, in addition to the detection during the developing operation, an accurate detection mode is provided in order to detect the remaining amount level more reliably. When it is detected that the surface of the toner is below a predetermined height several times in succession at a certain detection angle as described later, or when the user specifies, the accurate detection mode is entered at any time. I have to.

When the accurate detection mode is entered, the printing operation is stopped, and the driving motor consisting of a stepping motor for rotating the developing device so as to sequentially position each developing device at a predetermined developing position, is rotated forward and backward in small steps. The toner surface in the toner cartridge is leveled by repeating the vibration by repeating the movement.

Next, in order to prevent the toner adhering to the inner wall of the toner cartridge from erroneously detecting that there is toner in spite of the absence of toner, a mechanism for striking the toner cartridge in order to drop the adhered toner. , For example, actuating a solenoid described later.

The actual detection is carried out after the vibration of the drive motor and the striking operation are finished and a certain time has elapsed, and after the toner has stopped flowing in the toner cartridge.

In the following example, the detecting means is arranged at a predetermined fixed position so that the toner cartridge which moves in accordance with the rotation of the developing device sequentially passes through the detecting means, so that only one detecting means is used for the four toner cartridges. The remaining amount of toner of four colors of cyan, magenta, yellow, and black contained in the toner cartridge is detected. In each of the above-described detection during rotation and the accurate detection mode, a plurality of detection angles are set for one toner cartridge, and the remaining amount is determined from the detection result.

A description will be given below with reference to the drawings. FIG. 1 is a perspective view of a rotary developing device according to the present invention. A developing device that communicates with toner cartridges containing yellow, cyan, magenta, and black toners is housed in the cylindrical case 2, and rotates around the rotation axis X. Supported as possible.

At the time of development, the toner cartridges 1Y, 1M, 1C and 1K containing yellow, magenta, cyan and black toners in this order are also rotated together with the developing device to form a latent image formed on the latent image carrier. The developing device for the color corresponding to the image is stopped at the developing position to visualize the latent image as a toner image.

In this example, the detecting means 3 is fixed to a stationary member of the image forming apparatus main body so as to straddle the edge portion of each toner cartridge.

2 (a) and 2 (b) show the arrangement of the detecting means 3. As shown in FIG. FIG. 2A shows an optional toner cartridge 1.
2B is a partially enlarged front view of FIG.

In these figures, the detection means 3 is constituted by a U-shaped member, is in non-contact with the toner cartridge 1, and straddles the edge portion formed as a part of a circle, One of the two facing portions is provided with a light emitting section 4 and the other is provided with a light receiving section 5.
It constitutes a pair of detection means.

Here, the light emitting section 4 is an infrared LED and the light receiving section 5 is
Consists of a photodiode. The light emitting unit 4 and the light receiving unit 5 face each other at a narrow interval, and as shown in FIG. 1, they are the pass regions of the edges where the side portions of the toner cartridge intersect the peripheral surface, and their positions do not move in the lower part in the direction of gravity. It is located in.

The detecting means 3 is constructed so as to straddle the entire width of the toner cartridge 1 as shown in FIG. 2 (c), or a part of the toner cartridge 1 is stepped as shown in FIG. 2 (d). It is also possible to form the attached shape and straddle this narrow portion by the detection means 3.

In relation to this detection means, the toner cartridge 1 is made of a material such as light-transmitting PCB or polyethylene, and the presence or absence of toner inside the toner cartridge between the light emitting section 4 and the light receiving section 5. Can be detected.

An example of the toner detection method by changing the rotation angle will be described with reference to FIG. The detection means 3 is
The surface level 6 of the toner is detected at the height of the dotted line portion in the figure which is set as the level at which the near end of the toner can be detected.

Here, the toner near end is a display for giving advance notice of toner exhaustion before the printing operation is forcibly stopped because the toner is exhausted, and for example, 50 more are left.
This is when the printer is in a state where it is possible to print one sheet.

FIG. 3A is a rotational position where the reference line of the toner cartridge is 60 ° with respect to the vertical line, FIG. 3B is a rotational position with 80 ° with respect to the vertical line, and FIG. The rotation position is 90 ° with respect to the line, and FIG. 3D is the rotation position with 135 ° with respect to the vertical line.

In this way, FIG. 3 (a) → (b) → (c)
→ (d) As the rotation proceeds, the height of the toner with respect to the dotted line portion changes, and the toner amount can be detected by the detection unit 3.

FIG. 4 shows a timing chart for determining the remaining amount level. The respective time points shown in FIGS. 4A, 4B, 4C, and 4D correspond to the positions of the respective rotation angles in FIGS. 3A, 3B, 3C, and 3D. . The information about the rotation angle of the toner cartridge, that is, the position data in each of FIGS. 4A to 4D is the drive motor for driving the rotary developing device.
For example, since it is obtained from the drive pulse signal of the stepping motor, the remaining amount of toner in the toner cartridge in FIGS. 3A to 3D can be determined based on this position data and the output of the detection means.

In this example, 60 °, 80 °, 90 °, 13
Only at each rotation angle of 5 °, the light emitting section 4 of the detecting means 3 is caused to emit light to detect the remaining toner amount. When there is no toner at the level of the toner detecting means 3, the amount of transmitted light increases, and this becomes a detection signal when there is no toner.
As shown in (d), it is output as a pulse of the detection signal.

If there is such a detection signal for each rotation angle, the remaining amount of toner can be known by counting it. In the remaining toner amount state as shown in FIG. 3, the detection signal is output only once in FIG. 4D corresponding to the state in FIG. 3D, and the count value becomes 1.

In accordance with the reading of this count value, the remaining toner amount is displayed on the LED display means shown in FIG. 8 or the remaining amount level display means 7 which is a combination of a transparent plate and a lamp on which a graphic is drawn, Notify the user of the remaining toner amount.

The remaining amount level display means 7 is capable of discriminating four stages in the vertical direction, and a lamp is located corresponding to each stage, and the remaining amount of toner is visually indicated according to the lighting of these lamps. Can understand. Four such display means are provided corresponding to each toner cartridge.

When no detection signal is output at any of the four angular positions, that is, when the count value is 0, no light is transmitted at any angular position. There will be enough toner to replace the cartridge.

In this state, all are turned on and displayed on the display means shown in FIG. 8 for controlling the lighting of the lamps and notifying the toner amount corresponding to each level divided into four stages.

When the count value is 1, the light is transmitted at the angular position of 135 °. Therefore, in the toner cartridge, the display means 7 of FIG. It lights up and is displayed as shown in FIG.

When the count value is 2, light is transmitted at two angular positions. Therefore, in the toner cartridge, in the display means 7 of FIG. Will be displayed.

When the count value is 3, light is transmitted at three angular positions. Therefore, in the toner cartridge, in the display means 7 of FIG. 8, among the four lamps, the first one from the bottom is turned on. Will be displayed.

When the count value is 4, light is transmitted at four angular positions. Therefore, in the toner cartridge, all four lamps are turned off and displayed in the display means 7 of FIG. At this time, there is little toner remaining in the toner cartridge, for example, 50 prints become empty, that is, the toner is near end.

According to the first aspect of the invention, the above-described detection is performed while the toner cartridge is moving during the normal developing operation. Therefore, when the developing device is rotated to the position of the detecting means 3, the toner is detected. The surface 6 is not always horizontal due to the deviation of the toner, and it is considered that accurate detection cannot be performed.

Further, as the toner cartridge repeatedly rotates, the toner repeatedly flows in the toner cartridge, so that the toner adheres to the inner wall of the toner cartridge, and there is toner even though there is no toner. It may be detected.

In order to solve the above problems, an accurate detection mode for detecting the accurate remaining amount is provided. In this mode, the printing operation is stopped, and the drive motor that drives the developing device is repeatedly oscillated in small increments in the normal developing direction and the opposite direction to vibrate, and the toner surface of the toner cartridge at the detection position is made horizontal. To do.

Further, as shown in FIG. 5, a solenoid 8 is provided on an immovable member in the vicinity of the toner cartridge 1, and the solenoid is operated to reciprocate to strike the toner cartridge to attach it to the inner wall of the toner cartridge. The toner 9 present is knocked off.

These operations are performed for one toner cartridge for four rotation angles shown in FIGS. 3A to 3D, and for other toner cartridges in the same manner, the remaining amount is accurately measured. Can be detected.

As described above, after the vibration of the drive motor and the striking operation of the solenoid are performed, the toner is flying in the toner cartridge, which may cause an erroneous detection. Therefore,
After the vibration of the motor and the hitting operation of the solenoid are stopped, a certain period of time (here, 3 seconds) is set, and the detection of the toner is started after the toner has stopped flowing.

The above-described accurate detection mode for accurately detecting the remaining amount is applied in either of the following two cases. ． [Normal Detection During Rotation When No Toner is Detected Multiple Times Continuously at a Certain Angle] In normal detection during rotation, the detection accuracy is low because each angle is detected during rotation of each toner cartridge.
As a result of detecting four times for any one toner cartridge, if no toner is detected at a certain angle, that is, if five consecutive times are detected, the end of the current printing operation is set to the accurate detection mode for the toner cartridge. Transition. The detection result is displayed on the display means 7 in FIG. 8 and held until the next correct detection mode is entered.

If no toner is detected at the angle of FIG. 3 (a), it is in the near end state, and all four lamps of the display means 7 of FIG. 8 are turned off. Even from this state, the toner cartridge is not completely empty, and about 50 sheets can be printed. Therefore, even if the toner near-end state is reached, printing may be continued, and the toner cartridge may be replaced after the toner cartridge becomes empty and the machine is stopped. Alternatively, the toner cartridge may be replaced as a toner cartridge.

Since development cannot be performed in the accurate detection mode,
Even if the print command is input, the user has to wait until the accurate detection mode ends, and the average print speed becomes slow. Therefore, in order to eliminate this problem as much as possible, normally, detection is performed during rotation without applying vibration or hitting motion, and it is possible to enter an accurate detection mode in which vibration or hitting motion is added only when necessary.

.. [When Accurate Detection Mode is Specified According to User's Designation] In this case, the accurate detection mode is executed for the designated toner cartridge, and the procedure according to the above is taken according to the detection result.

Next, the procedure in the accurate detection mode will be described with reference to the flowchart of FIG. In FIG. 6, in step 1, first, the drive motor is driven to rotate at a rotation angle of 60 °.
Move the toner cartridge to the position.

In step 2, the developing device is rotated by 1 (sec) in the forward direction which is the rotation direction during normal development. In step 3, it is rotated by 1 (sec) in the opposite direction.

In step 4, it is determined whether the operations of steps 2 and 3 have been repeated three times. In step 5, the toner attached to the inner wall of the toner cartridge is removed by the solenoid described in FIG.

In step 6, it waits 3 (sec) until the toner is calmed down. In step 7,
The light emitting unit 4 is caused to emit light to perform actual toner end detection.
In step 8, it is determined whether toner end detection has been performed for four types of rotation angles. If not, repeat from step 1. In step 9, the toner cartridge is returned to the original position.

When such an accurate detection mode is entered, the printing operation is interrupted by displaying the display as shown in FIG. 7 by the LED or lamp of the operation panel or by issuing a beep sound by the buzzer. Inform the user that

According to the example of the structure corresponding to claim 1, by continuously detecting the rotating toner cartridge, the remaining amount can be detected by only one set of the detecting means. Can be simplified and the cost can be reduced, and the reduction in printing speed can be suppressed.

According to the example of the structure corresponding to claim 2, the remaining amount can be accurately detected, and the rotating toner cartridge is continuously detected, and the accurate detection mode is set only when necessary. Therefore, it is possible to minimize the decrease in print speed.

According to the configuration example corresponding to claim 3, the user can accurately detect the remaining amount of toner in the toner cartridge at any time.

According to the example of the structure corresponding to claim 4, the remaining amount can be detected by only one set of detecting means,
It is possible to simplify the device and reduce the cost.

According to the example of the configuration corresponding to claim 5, the user can know the reason for entering the accurate detection mode and waiting for printing.

According to the example of the configuration corresponding to claim 6, the level of the toner can be leveled to accurately detect the remaining amount of toner in the toner cartridge.

According to the example of the structure corresponding to claim 7, erroneous detection can be prevented by dropping the toner adhering to the inner wall of the toner cartridge.

According to the example of the configuration corresponding to claim 8, erroneous detection can be prevented by performing detection after the toner has stopped flowing in the toner cartridge.

According to the example of the structure corresponding to claim 9, the remaining toner amount can be detected by only one set of detecting means, and the apparatus can be simplified and the cost can be reduced.

[0073]

According to the present invention, the toner remaining amount level can be detected reliably with only one set of detecting means without increasing the cost.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating a rotary developing device suitable for carrying out the present invention together with a detection unit.

FIG. 2A is a perspective view of an arbitrary toner cartridge described together with a detection unit, FIG. 2B is a front view of FIG. 2A, and FIG. 2C is a toner cartridge and detection unit. FIG. 2D is a perspective view illustrating still another example of the toner cartridge and the detection unit.

FIG. 3 is a diagram illustrating a change in the toner surface level for each rotation angle of the toner cartridge together with a detection unit.

FIG. 4 is a diagram illustrating a detection signal for each rotation angle of the toner cartridge in association with the angle in FIG.

FIG. 5 is a diagram schematically illustrating a mechanism for hitting a toner cartridge.

FIG. 6 is a flowchart illustrating a process in an accurate detection mode for accurately detecting a remaining toner amount.

FIG. 7 is a diagram illustrating a display content informing that the printing operation is stopped in the accurate detection mode.

FIG. 8 is a diagram illustrating a display example of a toner remaining amount level.

[Explanation of symbols]

 1 toner cartridge 3 detection means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Irie 1-3-6 Nakamagome, Ota-ku, Tokyo, Ricoh Co., Ltd.

Claims (9)

[Claims] 1. A plurality of developing devices which are rotatably supported around a rotating shaft and each contain a predetermined powder developer, and the developing devices are provided corresponding to each developing device in order to replenish toner to the developing devices. And a plurality of developing devices are rotated together with the respective toner cartridges to bring a predetermined developing device to a developing position facing the latent image carrier, and the developing device causes the latent image carrier to move. In a rotary developing device that visualizes the formed electrostatic latent image as a toner image, the remaining toner level in each of the rotating toner cartridges does not move due to the rotation of the rotary developing device. A method for detecting a remaining amount of toner in a non-contact manner with the above-mentioned optical type detection means, wherein the detection is performed while the toner is rotating. 2. The accurate detection mode according to claim 1, wherein when the toner surface is detected to be below a predetermined height a plurality of times consecutively, the remaining amount is accurately detected. A method for detecting the remaining amount of toner. 3. The toner remaining amount detecting method according to claim 1 or 2, wherein an accurate detection mode is entered according to a user's designation. 4. The toner according to claim 1, 2, or 3, wherein the remaining amount of toner in the toner cartridge is determined by using position data that changes when the rotary developing device is driven. Remaining amount detection method. 5. The toner remaining amount detecting device according to claim 2 or 3, further comprising means for notifying a user that the accurate detection mode has been entered. 6. The accurate detection mode according to claim 2 or 3, wherein a drive motor for rotating the developing device so that the plurality of developing devices are located at predetermined developing positions is provided in a normal developing direction and a reverse direction. A method for detecting the remaining amount of toner, which is characterized by repeatedly vibrating in small steps. 7. The toner remaining amount detecting device according to claim 2 or 3, wherein a mechanism for hitting the toner cartridge is provided outside the toner cartridge. 8. The toner remaining amount detecting method according to any one of claims 2 to 7, wherein the detection is performed after a lapse of a fixed time after the vibration of the driving motor and the striking operation are stopped. 9. A toner remaining amount detecting method according to claim 1, wherein detection is performed a plurality of times for one toner cartridge.