JPH0429270A - Developer feeding discharging mechanism - Google Patents

Abstract

PURPOSE:To shorten a handling time spent on the developer replacing working of a maintenance parson or an operator by providing a mechanism discharging the developer from a developing machine, a container housing the developer, a tank storing a fresh developer, and a mechanism newly feeding the developer. CONSTITUTION:A printer main body counts the number of printing pages, and a printer displays a message so as to urge the operator to replace the developer when the prescribed number of pages is obtained. The operator carries out the discharging working of the developer by turning on a switch for exchanging the developer. In other words, a discharging valve 9 is opened, after the lapse of a prescribed time a closing action is carried out. Then, the measurement of the fresh developer is carried out, that is, a measuring valve 6 is opened, a measuring tank is made full, and then, the measuring valve 6 is closed. Then, a feeding valve 7 is opened to feed the developer of a necessary amount to the developing machine 1. This consecutive actions (sequence) are automatically controlled. Thus, the number of times of the exchanging working of the developer by the maintenance parson or the operator can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a developer supply/discharge mechanism for exchanging the developer in a developer using a dry two-component developer in an electrophotographic system.

[Background of the invention]

Conventionally, maintenance personnel or operators have been responsible for discharging the developer that has reached the end of its life and supplying new developer.

The work usually involves collecting the expired developer into the empty container that contained the developer, and then supplying new developer from the inlet of the developing machine. The amount of developer filled in the developer container is normally the same amount as the amount of developer in the developing machine. Therefore, the developer in the developing machine must be replaced every time the developer reaches the end of its life. This has the disadvantage that, in the case of a printer that prints a large amount, the developer replacement cycle becomes short. still,
As the developing machine becomes smaller and lighter, the developing machine itself is also required to be smaller, and the developer capacity within the developing machine is also reduced to a walking capacity, which has the disadvantage of shortening the developer replacement cycle.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-described drawbacks of the prior art and to reduce the amount of effort required by maintenance personnel or operators to replace the developer.

[Summary of the invention]

The printer main body had a capacity that was approximately an integral multiple of the amount of developer in the developing machine. A developer storage tank is implemented. The printer automatically discharges the developer when the number of printed pages reaches the end of the developer's lifespan. The discharged developer at the end of its life is collected in the container that originally contained the new developer.

After the developer is discharged, the same amount of developer as the discharged developer is measured and supplied from the developer storage tank into the developing machine.

In this way, by making the developer storage tank approximately an integer multiple of the internal capacity of the developing machine, maintenance personnel or operators can supply developer to the storage tank once and use the empty developer container at that time for long-term development. By replacing the developer with the collected developer container, it is possible to replace the developer in the developing machine for an integral number of times at once.

[Embodiments of the invention]

A specific example of the present invention will be described below with reference to FIG.

The amount of developer contained in the developing machine 1 is 2 kg.

The storage tank 3 stores 4 kg of developer 4. The storage tank 3 is arranged at a higher position than the developing machine 1. The developing machine 1 and the storage tank 3 are connected via a developer measuring section 5, which is a mechanism for measuring the amount (2 kg) of developer to be introduced at one time. Further, a developer discharge port of the developing machine 1 is connected to a developer container 10 via a discharge valve 9 that controls opening and closing. The developer container 10 is the developing machine 1
It is located at a lower position and can store the same amount of developer as the storage tank 3.

The lifespan of the developer is approximately 200 pages per page, so it is approximately 40 pages long.
At page 0, the life of the developer 2 is reached and it is time to replace it. The printer body counts the number of printed pages, and when the number reaches 400 pages, the printer displays a message prompting the operator to replace the developer. By turning on the switch for developer replacement, the operator performs the developer discharge operation, that is, opens the discharge valve 9, and closes it after a predetermined time has elapsed, and then measures new developer, that is, opens the metering valve 9. 6 is opened and the metering tank 8 is filled, the metering valve 6 is closed and the supply valve 7 is opened to supply the required amount of developer to the developing machine 1. This series of operations (
sequence) is automatically controlled and performed.

Therefore, if 4 kg of developer 4 is stored in storage tank 3, developer replacement work will be avoided for at least two 800-page periods.

Although the storage tank 3 for the developer 4 in the above embodiment constitutes one component of the printer main body, it may be the developer container 10 itself.

The amount of new developer supplied is controlled by installing a developer measuring section 5 at the front stage of the developing machine 1, as shown in FIG.
A level sensor 11 for detecting the amount of developer 2 may be provided in the developing machine 1, and this may be used to control the amount of new developer supplied.

The printer counts the number of pages printed or the printing time, and when the number of pages or the lifespan of the developer reaches its lifespan, a message prompting the operator to replace the developer is displayed, and the operator turns on the switch to replace the developer. However, when the number of pages or time of life has been reached, the developer may be replaced automatically while printing is stopped for each print job.

Even if the amount of new developer to be supplied is controlled by the opening and supplying time of the supply valve 7, similar effects can be obtained and the structure can be mechanically simple.

〔Effect of the invention〕

According to the present invention, even in a small developing machine or a printer that prints a large amount, maintenance personnel or operators can extend the frequency of developer replacement work, and handle developer that easily stains clothes and hands. It is possible to reduce the number of printing operations and to improve the execution printing speed.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of a developer supply/discharge mechanism according to the present invention, and FIG. 2 is a block diagram of a developing device section of another embodiment of the present invention. In the figure, 1 is a developing machine, 2 is a developer in the developing machine 1, and 3 is a developing machine.
1 is a storage tank, 4 is a developer, 5 is a developer measuring section, 6 is a metering valve, 7 is a supply valve, 8 is a metering tank, 9 is a discharge valve, 1o is a developer container 11 is for detecting the amount of developer. It is a level sensor. Name of patent applicant Hitachi Koki Co., Ltd.

Claims (1)

[Scope of Claims] 1. In a developer supply and discharge mechanism of a developing machine using a dry two-component developer using an electrophotographic method, a mechanism for discharging the developer from the developing machine and storing the discharged developer A developer supply/discharge mechanism comprising a container, a tank for storing new developer, and a mechanism for supplying new developer from the tank to a developing machine. 2. The developer supply/discharge mechanism according to claim 1, wherein the capacity of the new developer storage tank built into the printer main body is at least equal to the developer capacity in the developing machine. 3. The developer supply and discharge mechanism according to claim 1, wherein the container for storing the discharged developer is an empty container that originally contained new developer. 4. The developer supply and discharge mechanism according to claim 1, wherein a series of developer replacement operations such as discharging the developer and supplying new developer are automatically performed. 5. The developer supply/discharge mechanism according to claim 4, wherein the developer replacement operation is automatically performed when a predetermined number of printed pages or printing time corresponding to the lifespan of the developer is reached. 6. The developer supply and discharge mechanism according to claim 5, wherein the storage tank is disposed at a higher position than the developing machine, and the developer container is disposed at a lower position than the developing machine. 7. Claim 1, characterized in that a mechanism is provided near the storage tank for measuring the amount of developing machine supplied into the developing machine.
The developer supply and discharge mechanism described. 8. The developer supply and discharge mechanism according to claim 1, further comprising a level sensor for detecting the amount of developer provided in the developing machine.