JPH10319705A - Image forming device - Google Patents

Abstract

(57) [Problem] To control the toner replenishment amount in one toner replenishment operation so that the toner is not excessively supplied from the toner container to the toner storing portion, and the toner near end in the toner container is accurately detected. And an image forming apparatus that can determine the image forming apparatus. A toner supply roller (8) for supplying toner from a toner hopper (7) to a developing device (3), a toner bottle driving device (10) for replenishing toner from the toner bottle (9) to the toner hopper, and the presence or absence of toner in the toner hopper are repeated at a predetermined timing. In a copying machine having a toner replenishing device having a toner sensor 74 to be detected and a control unit for controlling a toner bottle driving device based on the detection result of the sensor, the ratio of the number of times of toner detection to the predetermined number of toner sensor detections is Based on this, the toner supply amount in one toner supply operation is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile, and a printer.
A toner storage unit for temporarily storing toner to be supplied to the developing device, a toner supply unit for supplying toner from the toner storage unit to the developing device, a toner container for storing toner to be supplied to the toner storage unit, and the toner The present invention relates to an image forming apparatus including a toner replenishing unit that replenishes toner from a container to the toner storage unit and a toner detection unit that repeatedly detects the presence or absence of toner in the toner storage unit at a predetermined timing.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus provided with this kind of toner replenishing device, the presence or absence of toner in a toner storage section is repeatedly detected at a predetermined timing by a toner detection means, and the toner detection means detects that there is no toner. The number of toner absence detections is integrated from the start of the detection, and when the number of integrations reaches a predetermined number, the toner amount in the toner container is determined to be near end, or toner is supplied from the toner container to the toner storage unit. When the frequency of the operation reaches a predetermined frequency, it is determined that the toner is not actually replenished even though the toner replenishment operation is repeatedly performed, and the toner amount in the toner container is determined to be near end. Was known.

As a mechanism for replenishing toner from the toner container to the toner storing portion, for example, a toner bottle as a toner container having a spiral rib formed on its peripheral wall to guide the toner inside toward the opening is used. For example, a toner bottle is known in which the toner bottle is rotated for a predetermined time, and the toner inside the toner bottle flows out to the toner hopper side through the opening to supply the toner.

The toner replenishing operation is performed only for a predetermined time, and if the toner replenishing operation for the predetermined time is one toner replenishing operation, in a conventionally known toner replenishing mechanism, a toner container is moved from a toner container to a toner storing section. When the toner replenishment operation is performed for a predetermined time, the toner replenishment amount per one time is not constant, but changes according to the amount of toner contained in the toner container. Specifically, when the amount of toner in the toner container is large, the amount of toner replenishment per toner replenishment is large, but when the amount of toner in the toner container decreases, the amount of toner replenished per toner replenishment is small. The replenishment amount gradually decreases.

[0005]

However, when an image is formed on a document having a high image area ratio, the amount of toner consumed in the developing device increases. Then, at this time, if the amount of toner in the toner container is small and the amount of toner replenishment per toner replenishment to the toner storage part decreases, the toner consumption in the toner storage part becomes larger than the toner replenishment amount. Sometimes. If such a state continues for a long time, the amount of toner in the toner storage unit decreases, so that the number of times that the above-mentioned “no toner” is detected and the frequency of toner supply operation from the toner container to the toner storage unit increase, There is a problem that the toner in the toner container is determined to be the toner near end or the toner end even though a certain amount of toner remains in the container.

[0006] In order to prevent the above-mentioned problem that occurs when an image is formed on a document having a high image area ratio, the toner container is removed from the toner container when the amount of toner in the toner container decreases. It is also conceivable to set a large amount of toner replenishment per toner replenishment to the toner storage unit. However, with this setting, the toner supply amount increases in accordance with the amount of toner in the toner container. Therefore, when the amount of toner in the toner container is large, the amount of toner supplied to the toner storage unit becomes too large. There was a defect.

[0007] The above-mentioned problem in the determination of the toner near end or the toner end may occur even if the amount of toner replenishment per one toner replenishment operation does not change in accordance with the amount of toner contained in the toner container. This occurs when the state in which the consumption of toner in the toner storage unit is large compared to the amount of toner supplied to the toner storage unit continues, such as when copying a document with a high image area ratio continuously. There is a risk. In addition, the problem that the toner replenishment amount to the toner storage unit becomes too large may occur even if the toner replenishment amount per one toner replenishment operation does not change according to the toner amount stored in the toner container. This may occur when the state in which the consumption amount of toner in the toner storage unit is small compared to the amount of toner supplied to the toner storage unit continues.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to replenish toner from a toner container to a toner storage section when the amount of toner in the toner container is sufficient. An object of the present invention is to provide an image forming apparatus that can accurately determine whether a toner is near or at the end of toner in a toner container.

[0009]

According to a first aspect of the present invention, there is provided an image forming apparatus, comprising: a toner storage unit for temporarily storing toner to be supplied to a developing device; A toner supply unit for supplying toner to the toner container, and a toner container for storing toner to be supplied to the toner storage unit.
An image forming apparatus provided with a toner replenishing device including a toner replenishing unit that replenishes toner from the toner container to the toner storing unit and a toner detecting unit that repeatedly detects the presence or absence of toner in the toner storing unit at a predetermined timing. ,
A toner supply amount control means for controlling the toner supply amount by the toner supply means based on a ratio of the number of times that the toner detection means detects the absence of toner to the predetermined number of times is provided. It is assumed that.

In the image forming apparatus according to the first aspect, the presence or absence of toner in the toner storing section is repeatedly detected at a predetermined timing by the toner detecting means. When the amount of toner in the toner storage section becomes equal to or less than a predetermined value and the toner detection section detects that there is no toner, the toner supply section controls the toner supply section and supplies toner from the toner container into the toner storage section. Here, if the amount of toner replenishment to the toner storage unit per one replenishment operation of the toner replenishment unit is smaller than the amount of toner consumed by the toner storage unit, the toner detection unit detects the presence of toner after the toner replenishment. The period from when the detection of the absence of toner to the start of detection is shortened. That is, of the predetermined number of times of detection by the toner detection unit, the ratio of the number of times that toner is detected to the predetermined number of times to the toner storage unit is determined by the ratio of the toner consumption to the toner storage unit per one replenishment operation of the toner storage unit. Increases as the toner supply amount decreases. If the ratio of the number of times of toner absence detection is equal to or higher than a certain ratio, it may be considered that the absence of toner in the toner storage unit is frequently detected even though toner is being supplied to the toner supply unit. Therefore, when the ratio of the number of times of toner absence detection exceeds a preset ratio, the toner supply amount by the toner supply unit is increased by the toner supply amount control unit. At this time, if there is toner in the toner storage section, a larger amount of toner is supplied to the toner storage section, and the toner in the toner storage section can be brought into the toner-present state. As a result, while toner is present in the toner container, the ratio at which no toner is detected is reduced, thereby avoiding the determination of toner near end or toner end.

According to a second aspect of the present invention, there is provided an image forming apparatus, comprising: a toner storage unit for temporarily storing toner to be supplied to a developing device; a toner supply unit for supplying toner from the toner storage unit to the developing device; A toner container that stores the toner to be replenished; a toner replenishing unit that replenishes the toner from the toner container to the toner storage unit; and a toner detection unit that repeatedly detects the presence or absence of toner in the toner storage unit at a predetermined timing. In the image forming apparatus provided with the toner replenishing device, the toner replenishing amount by the toner replenishing unit is determined based on a ratio of the number of toner replenishment by the toner replenishing unit to the predetermined number of times of the detection by the toner detecting unit. The toner supply amount controlling means for controlling the toner supply amount is provided.

In the image forming apparatus according to the present invention, if the amount of toner supplied to the toner storage unit per one replenishing operation of the toner replenishing unit is smaller than the amount of toner consumed by the toner storage unit, the amount of toner supplied after toner replenishment is reduced. The period from when the toner detecting means detects the presence of the toner to when the toner replenishing means replenishes the toner based on the toner absence detection gradually becomes shorter. That is, the ratio of the number of toner replenishment by the toner replenishing unit to the predetermined number of the toner replenishment by the toner replenishing unit among the predetermined number of detections by the toner detecting unit is determined by the ratio of the toner storage per toner replenishing unit to the toner consumption of the toner storing unit. The amount increases as the toner supply amount to the unit decreases. Then, when the ratio of the number of times of toner replenishment becomes equal to or greater than a predetermined ratio set in advance, the amount of toner replenishment by the toner replenishment unit is increased by the toner replenishment amount control unit. At this time, the toner in the toner container can be set in the toner-present state. As a result, while the toner is in the toner container, it is possible to prevent the toner from being determined to be near end or toner end.

According to a third aspect of the present invention, in the image forming apparatus of the first or second aspect, the toner supply amount per one time is controlled by the toner supply amount control means. The amount of toner replenishment is controlled so as to change in response to the following conditions.

Here, as the amount of toner in the toner container gradually decreases, the amount of toner replenishment to the toner storage unit per one predetermined replenishing operation by the toner replenishing means decreases.

In the image forming apparatus according to the third aspect, when the amount of toner contained in the toner container decreases, the toner replenishment amount control means increases the amount of toner replenishment per one toner replenishment operation, thereby increasing the amount of toner in the toner container. A desired toner supply amount can be obtained even when the remaining toner amount becomes small.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an electrophotographic copying machine (hereinafter, referred to as a "copying machine") as an image forming apparatus will be described. [First Embodiment] First, a schematic configuration and operation of the entire copying machine according to a first embodiment will be described. FIG. 1 is a schematic configuration diagram of the copying machine. In FIG. 1, a drum-shaped photoreceptor 1 as an image carrier is rotatably mounted, and a corona charger 2, a developing device 3, a transfer device (transfer charger) 4, a cleaning device 5, a charge removing device 5 are provided around the drum. A device (static elimination lamp) 6 and the like are provided.

The developing unit 3 is a developing unit employing a dry developing method using a so-called two-component developer composed of a toner and a carrier.
1, developing impeller 32, mixing roller 33, separator 3
4, a horizontal stirring screw 35, a toner density sensor (hereinafter referred to as "T sensor") 36 for detecting the toner density inside the developing device 3 located immediately below the mixing roller 33, and the like.

In the copying machine having the above structure, the photosensitive member 1 is uniformly charged by the corona charger 2 and then subjected to image exposure, whereby an electrostatic latent image corresponding to an image is formed on the photosensitive member 1. Is done. In the developing unit 3, the toner is charged to a polarity such that the toner adheres to the electrostatic latent image by frictional charging with the carrier by stirring the developer. The charged developer is pumped up by the developing roller 31 and comes into contact with the surface of the photoconductor 1. At the time of this contact, the electrostatic latent image on the photoconductor 1 is developed. The toner image formed on the photoreceptor 1 by this development is transferred onto transfer paper by a transfer device 4 and fused onto the transfer paper by a fixing device (not shown).
The transfer paper is discharged out of the machine. After the transfer, the surface of the photoreceptor 1 is cleaned by the cleaning device 5, and after the charge is removed by the charge removing lamp 6, it is charged again and the image formation is repeated.

The toner of the developer in the developing device 3 is consumed by such an image forming operation. However, if the toner concentration in the developing device 3 detected by the T sensor 36 deviates from a predetermined value, the deviation amount is reduced. Accordingly, the toner is supplied into the developing device 3 by the toner supply device described later, so that the image density is kept constant.

Next, the configuration of a toner supply device for supplying toner to the developing device 3 will be described. This toner replenishing device is mounted above the mixing roller 33 of the developing device 3, and serves as a toner hopper 7 as a toner storage section for temporarily storing toner to be supplied to the developing device 3, and transfers toner from the toner hopper 7 to the developing device 3. A toner supply roller 8 and a driving device for the toner supply means, a toner bottle (not shown in FIG. 1) as a detachable toner container, and a toner supply for supplying toner to the toner hopper 7 from the attached toner bottle. And a toner bottle driving device (not shown in FIG. 1).

FIG. 2A is a perspective view of one end of the toner hopper 7 shown together with a main control unit block according to the present invention, and FIG. 2B is a view of one end of the toner hopper 7 and the toner bottle 9. It is a perspective view. The toner hopper 7 moves in a direction orthogonal to the photoconductor surface moving direction (hereinafter, “photoconductor axis direction”).
), And a toner receiving port 72 formed at one end of the case 71 in the axial direction of the photoconductor (the front end in FIG. 1) so as to receive the toner discharged from the toner bottle 9. A toner conveying screw 73 (see FIG. 1) as a toner conveying means for conveying the toner received from the toner receiving port 72 toward the other end in the axial direction of the photoreceptor (the rear end in FIG. 1) and its driving. It has a device and the like. Further, a toner sensor 74 as a toner detecting means for detecting the presence or absence of toner in the toner hopper 7 is provided in a toner conveying path in the case 71 near the toner receiving port 72. The toner sensor 74 can be configured using, for example, a piezoelectric vibrator. A detection surface facing the toner conveying path is vibrated by the piezoelectric vibrator, and the vibration is hindered by toner adhesion to detect the presence or absence of toner. .

Further, the toner hopper 7 is moved from the toner bottle 9 to the toner hopper 7.
A bottle holding unit 11 for holding the toner bottle 9 via a roller (not shown), and a motor as a toner container drive source for applying a rotational driving force to the toner bottle 9 12
In addition, a bottle receiving portion 14 which holds the drive transmission gear train 13 and the opening of the toner bottle 9 via a bearing (not shown) and has a discharge port 14a on the toner hopper 7 side is provided.

The toner bottle 9 which is rotatably and detachably mounted on the toner bottle driving device 10 by a user's hand is, for example, a cylindrical bottle formed of a resin material. An opening for replenishing the toner hopper 7 is provided. Further, the toner stored in the inner peripheral surface of the toner bottle 9 is filled with an opening 9b.
Spiral ribs 9a are formed to guide in the direction of. Further, on the outer peripheral surface of the toner bottle 9, there is provided a gear portion 9 b which meshes with the last gear of the drive transmission gear train 13 to transmit a rotational driving force.

The control unit of the copying machine according to the present embodiment is shown in FIG.
As shown in (a), an MPU 100 as a main control unit is provided.
The operation display unit 200 and the like are connected to control each unit and process signals transmitted from each unit.

In the copying machine having the above configuration, when the image forming operation is repeated and the toner concentration in the developing device 3 decreases,
A toner supply signal is output from the control unit based on the detection result of the T sensor 36, a clutch (not shown) is turned on, and the toner transport screw 73 and the toner supply roller 8 start rotating. The rotation time of the toner supply roller 8 is controlled by the T sensor 36 so that the toner density in the developing device 3 is kept constant.
Was changed according to the detection result of the toner density.

In the above copying machine, the toner sensor 74 detects the presence / absence of toner in the toner hopper 7 every time one copy is made. In response to the toner bottle drive ON signal output from the unit, the motor 12 starts rotating and rotates the toner bottle 9 via the gear train 13 for 0.7 seconds. As described above, since the spiral rib 9 a is provided on the inner peripheral surface of the toner bottle 9, the toner stored in the toner bottle 9 is gradually moved to the opening of the toner bottle 9 by this rotation. And is discharged to the toner receiving port 72 of the toner hopper 7. The toner supplied from the toner receiving port 72 is conveyed in the toner hopper 7 in the axial direction of the photoconductor by the toner conveying screw 73, and falls uniformly onto the toner supply roller 8.

Here, in the copying machine having the above configuration, A4
The number of times that the toner sensor 74 detects the presence or absence of toner (A) and the number of times that the toner sensor 74 detects “no toner” (B)
(B / A) and changes in the amount of toner in the toner container were checked. As a result, as the amount of toner in the toner bottle 9 decreases, the frequency of detecting “no toner” increases, and even though about 80 g of toner remains in the toner bottle 9, it is determined that the toner is out and the apparatus is determined to be out of toner. Turned out to stop. Thus, in the present embodiment, the control unit controls the toner supply amount in one toner supply operation based on the frequency (B / A) of detecting “no toner”. (Hereinafter, margin)

FIG. 3 is a graph showing the relationship between the change in the frequency of detecting “no toner” and the remaining amount of toner in the toner bottle 9. The solid line in the figure indicates the rotation time of the toner bottle 9 in which the toner supply from the toner bottle 9 to the toner bottle 9 is performed every time the detection result of the toner presence / absence detection of the toner sensor 74 is detected as “no toner” five consecutive times. (Less than,
(The replenishment operation time) is set to 0.7 seconds / time, and the dashed line indicates the replenishment operation time of toner replenishment performed at the same timing as described above.
0.7 seconds / time while the value is less than 3, and (B / A) is set to 0.
If it becomes three or more, it is a result according to the present embodiment when 1.4 seconds / time is set. As shown in FIG. 3, (B /
When A) becomes 0.3 or more, the supply operation time is set to 1.4 seconds /
When the toner was replenished, the remaining amount of toner in the toner bottle 9 was about 15 g and stopped at the toner end. As a result, it was possible to copy about 600 more copies in comparison with the case where the toner supply operation time was always kept constant at 0.7 seconds / time before the apparatus stopped at the toner end.

After the toner replenishing operation from the toner bottle 9 to the toner hopper 7, the value of (B / A) temporarily changes.
Is determined, the likelihood of the toner near-end determination changes. Based on the past data (B
/ A) is calculated as follows: if (A) is small, (B
/ A) is easy to understand the degree of change, but fluctuates greatly,
If (A) is large, it is easy to catch the whole change by wiping out a small error, but it is desirable to set according to the needs in view of the fact that the difference from the current situation is likely to be large. In the first embodiment, the calculation is performed based on the past 200 data as the setting condition (A).
Since the characteristics shown in FIG. 3 change depending on the size of the machine, the CPM, and the like, and the appropriate setting conditions change, the above condition setting may be performed according to the size of the machine, the CPM, and the like.

As described above, according to the first embodiment, the phenomenon that the amount of toner to be replenished in a fixed toner replenishing operation time decreases as the amount of toner in the toner bottle 9 decreases is used to detect the absence of toner. Based on the frequency (B / A), the toner supply operation time in one toner supply can be controlled to control the toner supply amount. By controlling the toner replenishment amount in this way, the toner is not replenished from the toner bottle 9 to the toner hopper 7 when the toner amount in the toner bottle 9 is sufficient.
Further, when the remaining amount of toner in the toner bottle 9 decreases, the amount of toner consumption in the developing device increases, such as copying of an image having a high image area ratio, and the amount of toner consumption in the toner bottle 9 increases. In addition, the toner supply amount from the toner bottle 9 to the toner bottle 9 is insufficient.
It does not happen that the toner near end or the toner end is determined in a state where a sufficient amount of toner remains in the inside.

In the first embodiment, the amount of toner supply from the toner bottle 9 to the toner bottle 9 is controlled by changing the toner supply operation time. Is maintained at 0.7 seconds / time, and when (B / A) becomes 0.3 or more, the same toner replenishing operation is repeated twice, or one toner replenishing operation time is set to 0.7. (B / A)
May be controlled to increase the number of rotations of the toner bottle 9 to control the toner supply amount.

[Second Embodiment] Next, a copying machine according to another embodiment in which the present invention is applied to a copying machine will be described. The overall configuration and operation of the copying machine according to the present embodiment are the same as those in the first embodiment, and a description thereof will be omitted.

Also in the present embodiment, the toner sensor 74 detects the presence or absence of toner in the toner hopper 7 every time one copy is made. In response to the toner bottle drive ON signal output from the unit, the motor 12 starts rotating and rotates the toner bottle 9 via the gear train 13 for 0.7 seconds.

In the present embodiment, the copying operation of the original image having the image area ratio of 20% of the A4 landscape size is continued, and the number of toner replenishment operations (A) of the toner sensor 74 (A) The change in the ratio (S / A) of S) and the amount of toner in the toner container was checked. As a result, as the amount of toner in the toner bottle 9 decreases, the frequency of the toner replenishing operation to the toner hopper 7 increases quickly, and even though approximately 80 g of the toner remains in the toner bottle 9, It was determined that the device would shut down. Therefore, in the present embodiment, as shown in FIG. 4, the control unit measures the number of times the motor 12 for rotating the toner bottle 9 is driven, and determines the ratio of the number of toner supply operations (S / S).
The toner supply amount in one toner supply operation is controlled based on A).

FIG. 5 is a graph showing the relationship between the change in the frequency of toner supply operation to the toner hopper 7 and the remaining amount of toner in the toner bottle 9. The solid line in the figure indicates the rotation time of the toner bottle 9 in which the toner supply from the toner bottle 9 to the toner bottle 9 is performed every time the detection result of the toner presence / absence detection of the toner sensor 74 is detected as “no toner” five consecutive times. (Hereinafter, referred to as “supply operation time”) is set to 0.7 seconds / time. The dotted line indicates the replenishment operation time of toner supply performed at the same timing as described above.
0.7 seconds / time while A) is less than 0.1, (S /
This is the result according to the present embodiment when 1.4 seconds / time is set when A) becomes 0.1 or more. As shown in FIG. 5, when (S / A) becomes 0.1 or more, when the replenishing operation time is set to 1.4 seconds / time and the toner is replenished, the remaining toner amount in the toner bottle 9 becomes about 10 g. And stopped at toner end. As a result, about 650 more copies could be made as compared with the case where the toner supply operation time was always kept constant at 0.7 seconds / time before the apparatus stopped at the toner end.

After the toner replenishing operation from the toner bottle 9 to the toner hopper 7, the value of (S / A) temporarily changes.
Is determined, the likelihood of the toner near-end determination changes. (S
/ A) may be calculated if (A) is small (S
/ A) is easy to understand the degree of change, but fluctuates greatly,
If (A) is large, it is easy to catch the whole change by wiping out a small error, but it is desirable to set according to the needs in view of the fact that the difference from the current situation is likely to be large. In the second embodiment, as the setting condition of (A), the calculation is performed based on the past 200 data.
Since the characteristics shown in FIG. 5 change depending on the size of the machine, the CPM, and the like, and appropriate setting conditions change, the above-described condition setting may be performed according to the size of the machine, the CPM, and the like.

As described above, according to the first embodiment, the toner replenishing operation frequency is utilized by taking advantage of the phenomenon that the amount of toner replenished in a fixed toner replenishing operation time decreases as the amount of toner in the toner bottle 9 decreases. Based on (S / A), the amount of toner replenishment can be controlled by controlling the toner replenishment operation time in one toner replenishment. By controlling the toner replenishment amount in this way, the toner is not replenished from the toner bottle 9 to the toner hopper 7 when the toner amount in the toner bottle 9 is sufficient. Further, when the remaining amount of toner in the toner bottle 9 decreases, the amount of toner consumption in the developing device increases, such as copying of an image having a high image area ratio, and the amount of toner consumption in the toner bottle 9 increases. In addition, the toner replenishment amount from the toner bottle 9 to the toner hopper 7 is not sufficient, and the toner near end or the toner end is not determined in a state where a sufficient amount of toner remains in the toner bottle 9.

In the second embodiment, the amount of toner replenishment from the toner bottle 9 to the toner bottle 9 is controlled by changing the toner replenishment operation time. Is maintained at 0.7 seconds / time, the same toner replenishing operation is repeated twice when (S / A) becomes 0.1 or more, or one toner replenishing operation time is reduced to 0.7. (S / A)
May be increased by increasing the number of rotations of the toner bottle 9 to control the toner supply amount.

[0039]

According to the image forming apparatus of the first aspect, when the ratio of the number of times of detecting the absence of toner to the predetermined number of detections among the predetermined number of times detected by the toner detecting means becomes higher, the toner is supplied to the toner storage section. Since the amount of toner is increased, the amount of toner consumed in the toner storage unit is large even though the toner remains in the toner container, and the empty state of the toner storage unit continues to determine the toner near end or the toner end. Therefore, there is an excellent effect that the toner near end or the toner end can be accurately determined regardless of the amount of toner remaining in the toner container and the amount of toner consumed in the toner storage unit. In addition, since the toner replenishment amount from the toner container to the toner storage unit is controlled based on a ratio of the number of times that the toner detection means detects the absence of toner to the predetermined number of times, the toner consumption of the toner storage unit is controlled. The toner replenishing amount can be increased only when the toner replenishing amount per one replenishing operation of the toner replenishing means for the toner replenishing unit with respect to the toner amount is small, and when the toner amount in the toner container is sufficient, The toner is not replenished from the container to the toner storing portion.

According to the image forming apparatus of the present invention, when the ratio of the number of toner replenishment by the toner replenishing unit to the predetermined number of the predetermined number of times detected by the toner detecting unit becomes high, the toner replenishment to the toner storing unit is performed. Since the amount of toner is increased, the amount of toner consumed in the toner storage unit is large even though the toner remains in the toner container, and the empty state of the toner storage unit continues to determine the toner near end or the toner end. Therefore, there is an excellent effect that the toner near end or the toner end can be accurately determined regardless of the amount of toner remaining in the toner container and the amount of toner consumed in the toner storage unit. Since the toner replenishment amount from the toner container to the toner storage unit is controlled based on a ratio of the toner replenishment number by the toner replenishment unit to the predetermined number out of the predetermined number of times detected by the toner detection unit, the toner consumption of the toner storage unit is controlled. The toner replenishing amount can be increased only when the toner replenishing amount per one replenishing operation of the toner replenishing means for the toner replenishing unit with respect to the toner amount is small, and when the toner amount in the toner container is sufficient, The toner is not replenished from the container to the toner storing portion.

According to the image forming apparatus of the third aspect, when the remaining amount of toner in the toner container becomes small, the toner replenishing operation is performed.
Since the amount of toner replenishment per cycle is increased, the toner reservoir can be in the toner-present state even when the amount of toner remaining in the toner container is small or the number of toner replenishment operations is small, and the toner remains in the toner container. Nevertheless, it is possible to prevent the toner storage unit from being left empty even after replenishing the toner due to the large amount of toner consumption in the toner storage unit and subsequently determining the toner near end or the toner end. . Therefore, there is an excellent effect that the toner near end or the toner end in the toner container can be accurately determined regardless of the remaining amount of toner in the toner container. Further, even when the amount of toner contained in the toner container is reduced and the amount of toner supplied to the toner storage portion is substantially reduced in a predetermined toner supply operation, a sufficient amount of toner is supplied. When the amount of toner in the toner container is small, the amount of toner in the toner container can be sufficiently increased. In this case, there is an excellent effect that the toner is not replenished from the toner container to the toner storing portion.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a copying machine according to an embodiment of the present invention.

FIG. 2A is an explanatory diagram of a toner hopper and a control block of the copying machine. (B) is a perspective view of the toner hopper and the toner bottle driving device.

FIG. 3 is a graph showing a relationship between a change in the frequency of detecting “no toner” and the remaining amount of toner in a toner bottle.

FIG. 4 is an explanatory diagram of a toner hopper and a toner bottle driving device and a control block according to another embodiment.

FIG. 5 is a graph showing a relationship between a change in a frequency of a toner supply operation to a toner hopper and a remaining amount of toner in a toner bottle.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor 3 developing device 7 toner bottle 8 toner supply roller 9 toner bottle 10 toner bottle driving device 12 toner bottle driving motor 13 drive transmission gear train 36 toner density sensor 71 case 72 toner receiving port 73 toner conveying screw 74 toner sensor 100 MPU 200 operation display

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hiroshi Saito 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (3)

[Claims] A toner storage section for temporarily storing toner to be supplied to a developing device; a toner supply means for supplying toner from the toner storage section to the developing device; and a toner for storing toner to be supplied to the toner storage section. An image provided with a toner replenishing device having a container, a toner replenishing unit for replenishing toner from the toner container to the toner storing unit, and a toner detecting unit for repeatedly detecting the presence or absence of toner in the toner storing unit at a predetermined timing In the forming apparatus, a toner replenishing amount control unit that controls a toner replenishing amount by the toner replenishing unit based on a ratio of the number of times that the toner detection unit detects the absence of toner to the predetermined number of times is provided. An image forming apparatus characterized in that: 2. A toner storage section for temporarily storing toner to be supplied to a developing device, a toner supply means for supplying toner from the toner storage section to the developing device, and a toner for storing toner to be supplied to the toner storage section. An image provided with a toner replenishing device having a container, a toner replenishing unit for replenishing toner from the toner container to the toner storing unit, and a toner detecting unit for repeatedly detecting the presence or absence of toner in the toner storing unit at a predetermined timing In the forming apparatus, a toner supply amount control unit that controls a toner supply amount by the toner supply unit based on a ratio of the toner supply unit by the toner supply unit to the predetermined number of times of the detection by the toner detection unit. An image forming apparatus comprising: 3. The image forming apparatus according to claim 1, wherein
An image forming apparatus according to claim 1, wherein said toner supply amount control means controls the toner supply amount such that the toner supply amount per operation changes in accordance with the amount of toner contained in said toner container.