JPH0962078A - Developing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing device and an image forming device by which abnormality on developer supply is prevented from being erroneously detected even in the case an image having high image ratio is formed on a condition that a warning is given as the remaining amount of the developer inside a developer supplying container is reduced. SOLUTION: A toner sensor 22 judges whether the toner remaining amount inside a hopper 20 is equal to or less than a specified amount, abnormal detecting time (t) is set to one minute in the case the sensor 22 judges that remaining amount is enough, and developing operation and abnormal detecting operation are performed can the condition. When the toner remaining amount inside the hopper 20 is equal to or less than the specified amount, the number of remaining copies is checked, and copying is inhibited in the case the number of copies reaches 500, and the abnormal detecting time (t) is set to 5 minutes in the case copying can be still performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic copying machine,
The present invention relates to an image forming apparatus such as an information recording apparatus and a developing apparatus used in the apparatus.

[0002]

2. Description of the Related Art In a conventional image forming apparatus, a developer is supplied from a developer supply container to the developer container, and an image is formed when the remaining amount of the developer in the developer supply container reaches a predetermined amount. There is one that prohibits the formation and prompts the user to replenish the developer.

In such an apparatus, there is no inconvenience on the apparatus side, but if the user does not have a stock of the developer to be replenished, the user waits until the user obtains the developer. There were times when I couldn't use it.

Therefore, a warning is issued when the remaining amount of the developer in the developer supply container is larger than the predetermined amount, and then a predetermined number of images are formed until the remaining amount of the developer reaches the predetermined amount and the image formation is prohibited. An image forming apparatus capable of achieving the above has been proposed and put into practical use.

Further, in such an apparatus, since the abnormality in the supply of the developer from the developer supply container to the developer container is detected, when it is detected that the remaining amount of the developer in the developer container is less than a predetermined amount. At the same time as requesting the developer supply to the developer supply container side, at the same time measuring the elapsed time after detecting that it is less than the predetermined amount, the remaining amount of the developer does not reach the predetermined amount. When the time exceeds a predetermined time, an error is displayed and image formation is prohibited.

[0006]

However, according to the above-mentioned conventional apparatus, the amount of the developer in the developer supply container is reduced when the warning is issued due to the decrease of the remaining amount of the developer in the developer supply container. Due to the decrease, the supply amount of the developer from the developer supply container to the developer container is smaller than usual, so when the image with a high image ratio is formed, the developer supply amount cannot keep up with the developer consumption amount, Although there is no abnormality in the supply of the developer, the error display and the inhibition of image formation may be executed in some cases.

Therefore, according to the present invention, even when an image with a high image ratio is formed in the state where the warning is issued due to the decrease of the remaining amount of the developer in the developer supply container,
An object of the present invention is to provide a developing device and an image forming apparatus that do not erroneously detect that the supply of the developer is abnormal.

[0008]

According to the first invention of the present application, the above object is to provide a developer container for containing a developer, and a developer supply container for supplying the developer into the developer container. A control means for controlling the supply of the developer from the developer supply container to the developer container, and a developer amount detection means for detecting the developer container and the amount of the developer in the developer supply container, In a developing device having an abnormality detection means for detecting an abnormality in the supply of the developer from the developer supply container to the developer container, the abnormality determination condition of the abnormality detection means is set in the developer container or in the developer supply container. It is achieved by changing the state of the developer inside.

According to the second invention of the present application,
The above object is to provide a latent image bearing member, a developer bearing member arranged to face the latent image bearing member, a developer container for accommodating a developer to be supplied to the developer bearing member, and the developer. A developer supply container for supplying the developer into the container, a control means for controlling the supply of the developer from the developer supply container to the developer container, the developer container and the developer in the developer supply container In the image forming apparatus including the developer amount detecting means for detecting the amount of the developer and the abnormality detecting means for detecting the abnormality of the supply of the developer from the developer supply container to the developer container, This is achieved by changing the determination condition according to the state of the developer in the developer container or the developer supply container.

Therefore, according to the first invention of the present application, the abnormality in determining the supply of the developer from the developer supply container to the developer container is determined by the developer supply container or the state of the developer in the developer container. For example, since the amount is changed according to the developer amount, even when the amount of supply from the developer supply container to the developer container is reduced while appropriately warning the user that the developer amount is small, Since the abnormality detection is performed according to the degree of the reduction, erroneous detection of the developer supply abnormality can be prevented regardless of the image ratio of the document.

Further, according to the second invention of the present application,
Since the supply abnormality determination condition of the developer from the developer supply container to the developer container in the image forming apparatus is changed according to the state of the developer in the developer supply container or the developer container, for example, the developer amount, Even when the amount of developer supplied from the developer supply container to the developer container is reduced, an abnormality is detected according to the extent of the decrease, while properly issuing a warning to the user that the developer amount is small. An erroneous detection of a developer supply abnormality is prevented regardless of the image ratio of the original, and good image formation is always performed.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) FIG. 1 is a flow chart for determining a developer supply abnormality detection time in the first embodiment of the present invention, and FIGS. 2 and 3 are a developer container to which the present invention is applicable and It is a schematic diagram of a development supply container.

In FIGS. 2 and 3, reference numeral 11 denotes a toner sensor including a piezoelectric element or the like as a developer amount detecting means,
The toner sensor 11 is provided in the developer container 10 of the developing device 1. Therefore, when the remaining amount of toner in the developing device 10 reaches a predetermined amount, the toner sensor 11 outputs a signal indicating that the remaining amount of toner has decreased, and in accordance with this output signal, the hopper 20 serving as a developer supply container. The transporting means 21 is driven to move the developer transporting section 30 from the hopper 20.
Toner as a developer is supplied to.

The toner thus supplied by the developer carrying section 30 is carried by the carrying screw 3 as a developer carrying means.
While being conveyed in the longitudinal direction of the developer container 10 by 1, the toner is dropped and supplied along the developer falling amount control wall 32, and further conveyed by the stirring and conveying member 12 to the developing sleeve 13 which is a developer carrier, and the developing sleeve. 13 is carried and carried by 13 to be used for developing the electrostatic latent image on the photosensitive drum 40 which is a latent image carrier.

Therefore, the developer container 10 is provided in the hopper 20.
If there is not enough toner to be supplied to the developer container 10, even if the toner sensor 11 outputs a signal indicating that the remaining amount of toner in the developer container 10 is small,
Therefore, an appropriate amount of toner cannot be supplied and the image cannot be output.

Therefore, a toner sensor 22 which is a developer amount detecting means in the hopper 20 is also provided in the hopper 20, and when the toner sensor 22 detects that the remaining amount of toner in the hopper 20 is below a predetermined amount, the user It was proposed to display a message prompting to replenish the toner and prohibit copying.

However, with such a structure, if there is no toner stock to be supplied to the hopper 20,
In some cases, copying could not be performed until the toner was obtained, and the device could not be used efficiently.

Therefore, in the present embodiment, the reference amount when the toner sensor 22 determines that the remaining amount of toner in the hopper 20 has become less than or equal to a predetermined amount is set to be larger than the conventional amount, and toner is supplied to the user. Even after the prompting message is displayed, a predetermined number of copies can be made.

After the toner sensor 22 detects that the amount of remaining toner in the hopper 20 is small, the number of copies is counted, and when the count value reaches 500, copying is prohibited.

That is, the user can make a copy up to 500 sheets after that even if there is no toner stock at the time the message prompting toner supply is displayed, and during that time, the user can obtain toner and obtain toner 20. Copying can be continuously performed by replenishing the toner.

However, even in the case of such a configuration, when a failure occurs in the conveying means 21 of the hopper 20, the toner is supplied to the developing device 10 although the toner is sufficiently present in the hopper 20. It is also possible that the image is not output. Further, when the toner sensor 11 fails, the toner is supplied to the developer container 10 and the developer container 10 is filled with the toner, even though the toner is sufficiently present in the developer container 10. May occur.

Therefore, in the present embodiment, if the state in which the toner sensor 11 detects that the amount of toner remaining in the developer container 10 has fallen below a predetermined amount continues for a predetermined time or longer, a failure occurs. Error is displayed and copying is prohibited.

If the predetermined time until it is determined that the failure has occurred (hereinafter, this time is referred to as an abnormality detection time) is set to be too long, it is impossible to avoid the situation where the toner sensor 11 becomes full in the case of failure. On the contrary, if it is too short, the toner sensor 11 detects the absence of toner and then the hopper 2
Since there is a time lag from when the toner is supplied from 0 to when the toner sensor 11 detects the presence of toner, it may be erroneously detected as a failure, so it is necessary to set it appropriately.

In the present embodiment, the abnormality detection time is set to 1 minute as a time sufficient to prevent erroneous detection while avoiding the above situation. Specifically, the developing device 1
Standard toner control amount within 0 200 ± 20g, hopper 20
Standard toner supply amount from the printer 40 ± 6 g / min, developing device 10
Maximum capacity 300g (toner equivalent) Copy speed 50
Since the number of sheets / minute (A4) and the maximum toner consumption amount are 25 g (sheets of black original), if the abnormality detection time t is set to 1 minute, the apparatus side will not be damaged even when an error occurs.

However, when the amount of toner in the hopper 20 becomes less than a predetermined amount, the amount of toner supplied from the hopper 20 decreases as shown in FIG. 4, so if the abnormality detection time is left at 1 minute. However, there is a case where the toner consumption amount is large and the toner supply amount cannot catch up, and in one minute, sufficient toner is not supplied to the developer container 10, and an error may occur even though it is not a malfunction.

Therefore, in the present embodiment, after the toner sensor 22 in the hopper 20 detects that the amount of toner in the hopper 20 is less than or equal to a predetermined amount, the abnormality detection time is lengthened and t = 5 minutes. Set to.

That is, as shown in FIG. 1, first, the toner sensor 22 determines whether or not the remaining amount of toner in the hopper 20 is below a predetermined amount (step S1).
When it is determined that there is still a sufficient remaining amount, the abnormality detection time t is set to 1 minute (step S2), and the developing operation and the abnormality detection operation are performed in this state. But the hopper 20
If it is determined that the remaining amount of toner in the inside is less than or equal to the predetermined amount, the remaining copyable number is checked (step S
3) If the number of copies reaches 500, the copy is prohibited (step S4), but if the copy is still possible, the abnormality detection time t is set to 5 minutes.

By setting in this way, even if the solid black original is continuously copied in the state where the toner in the hopper 20 is insufficient and the message for prompting the toner replenishment as described above is displayed, an erroneous detection may occur. No error occurred.

Here, the toner supply amount of the hopper 20 will be described with reference to FIG. First, the performance required for the hopper 20 is that the toner supply amount is enough to catch up with the toner consumption amount, and that the toner amount is replenished at any time after detecting that the toner amount in the hopper 20 is equal to or less than a predetermined amount. It is possible to cite that it has a toner receiving space for one toner cartridge.

The characteristics of the toner supply amount of the hopper are generally as shown in FIG. 4, and it is difficult to effectively use all the toner in the hopper 20 due to the influence of the dead space in the hopper 20. Therefore, if the abnormality detection time is fixed to 1 minute, the toner remaining amount in the hopper 20 is always high in order to secure a sufficient toner supply amount and prevent erroneous detection even for an image with a large toner consumption amount. It is necessary to keep in mind.

That is, in order to take such a configuration,
The capacity of the toner cartridge must be reduced to make the capacity of the hopper 20 the same, or the capacity of the toner cartridge must be made the same to increase the capacity of the hopper 20,
The former is unfriendly to the user in that the number of times of toner supply is increased, and the latter is disadvantageous in terms of cost and space.

However, by switching the abnormality detection time according to the amount of toner in the hopper 20 as in the present embodiment, it is possible to copy any original without any disadvantage in terms of cost and space. However, it is possible to provide a user-friendly device having a mechanism for notifying the user that the amount of remaining toner is low without causing erroneous detection of an error.

Needless to say, each set value shown in this embodiment can be set to an appropriate value corresponding to each device.

(Second Embodiment) FIG. 5 is a row chart for determining the developer supply abnormality detection time in the second embodiment of the present invention.

In the present embodiment, the first embodiment is divided into two cases, but after the toner sensor 22 in the hopper 20 detects the absence of toner, while the 500 sheets are being copied, the hopper 20 is Taking into consideration that it takes time for the toner amount in the developer container 10 to return to a steady state even after the toner is replenished to the hopper 20 when the toner supply amount from the developer container 10 to the developer container 10 cannot catch up. So, there are three cases.

That is, as shown in FIG. 5, first, the toner sensor 22 determines whether or not the remaining amount of toner in the hopper 20 is below a predetermined amount (step S1).
0), if it is determined that the remaining amount of toner in the hopper 20 is less than or equal to a predetermined amount, the remaining copyable number is checked (step S11). As a result, the number of copies is 50
If the number of sheets is less than 0, the abnormality detection time t is set to 2 minutes (step S12), and the toner supply to the hopper 20 is awaited. On the other hand, if the number of copies reaches 500, copying is prohibited (step S1).
3) Wait for toner to be supplied to the hopper 20.

Then, if the toner remaining amount in the hopper 20 is continuously checked and it is determined that the toner is supplied to the hopper 20 (step S10), the toner remaining amount in the developer container 10 is checked. Yes (step S1
4). As a result, when it is determined that the toner amount in the developer container 10 is in the steady state, the abnormality detection time t is set to 1 minute (step S15), but the toner amount in the developer container 10 decreases. If it is determined that the abnormality is not in the steady state, the abnormality detection time t is set to 3 minutes (step S16). In other words, in this case, it is considered that the amount of toner supplied from the hopper 20 to the developer container 10 cannot catch up, and it takes time for the amount of toner in the developer container 10 to return to a steady state even after the toner is supplied to the hopper 20. Therefore, the abnormality detection time is set to the longest.

Therefore, when the amount of toner in the developer container 10 is recovered thereafter, it is determined that the state has returned to the steady state, and the abnormality detection time t is set to 1 minute (steps S14 to S15).

As a result, the toner in the hopper 20 and the developer container 10 is sufficiently present, the toner in the hopper 20 is reduced, and the toner in the developer container 10 is also reduced. If there is an abnormality in each state in which the toner has been replenished in the developer container 20 but the toner in the developer container 10 has decreased, an error can be generated early and damage to the apparatus can be minimized. Can be suppressed.

(Third Embodiment) The present invention is not limited to the above-described two embodiments. For example, in an installation mode in which toner is supplied from an hopper to an empty developer container, or when the toner cohesion degree is around. The present invention can be applied to an apparatus in which it is necessary to change the setting of each developer supply abnormality detection time when the toner supply amount from the hopper changes due to the environment.

Further, in the above embodiment, the abnormal developer supply is detected according to the time when it is detected that there is no toner, but it is also possible to detect it based on other information such as the number of copies.

[0043]

As described above, the first embodiment according to the present application is described.
According to the invention, since the developer supply abnormality determination condition is changed according to the state of the developer supply container or the developer container, it is possible to determine what kind of development device the development device can be performed without increasing the size of the device or increasing the cost. Even in the state, it is possible to detect an abnormality before the device is seriously damaged, and prevent erroneous detection of the abnormality.

According to the second invention of the present application,
Since the condition for determining the supply abnormality of the developer in the image forming apparatus is changed according to the state of the developer supply container or the developer container, the state of the image forming apparatus can be determined without increasing the size of the device or increasing the cost. Even in this case, it is possible to detect the abnormality before the damage to the device is serious and prevent the erroneous detection of the abnormality.

[Brief description of drawings]

FIG. 1 is a flow chart for determining a developer supply abnormality detection time according to the first embodiment of the present invention.

FIG. 2 is a schematic view of a developer container and a hopper according to the first embodiment of the present invention.

FIG. 3 is a sectional view taken along the line A-A ′ of the developing device in FIG.

FIG. 4 is a graph showing the relationship between the remaining toner amount in the hopper and the toner supply amount.

FIG. 5 is a flowchart for determining a developer supply abnormality detection time according to the second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Developing device 10 Developer container 11 Toner sensor in a developing device (developer amount detection means) 13 Developing sleeve (developer carrying body) 20 Hopper (developer supply container) 22 Toner sensor in hopper (developer amount detection means) 40 Photosensitive drum (latent image carrier)

Claims (2)

[Claims] 1. A developer container for containing a developer, a developer supply container for supplying the developer into the developer container, and a supply of the developer from the developer supply container to the developer container are controlled. Control means, a developer amount detecting means for detecting the amount of the developer in the developer container and the developer supply container, and an abnormality in the supply of the developer from the developer supply container to the developer container. In a developing device having an abnormality detecting means, the abnormality determining condition of the abnormality detecting means is changed according to the state of the developer in the developer container or the developer supply container. 2. A latent image carrier, a developer carrier arranged to face the latent image carrier, a developer container for accommodating a developer to be supplied to the developer carrier, and the developing device. A developer supply container for supplying the developer into the developer container, a control means for controlling the supply of the developer from the developer supply container to the developer container, the developer container and the development in the developer supply container In the image forming apparatus including the developer amount detecting means for detecting the amount of the developer and the abnormality detecting means for detecting the abnormality in the supply of the developer from the developer supply container to the developer container, An image forming apparatus, wherein the abnormality determination condition is changed according to the state of the developer in the developer container or the developer supply container.