JPH01188878A - Developing device - Google Patents

Abstract

PURPOSE:To assure printing from after a toner is empty until a toner is supplied by being equipped with a toner sub-tank mechanism to supply toners by the number of printed and assured sheets. CONSTITUTION:A toner sub-tank 3 to charge the number of toners to be printed and assured in order to print after it is detected that the toner is empty, at a part of a toner tank 2 and a supplying port 3a of the toner sub-tank 3 is sealed with a film 11. Consequently, when it is detected that the toner is empty, by the change of the torque of a mixer 4, the film 11 is separated, and the toner can be supplied from the toner sub-tank 3 into the toner tank 2. Thus, the printing and assuring after it is detected that the toner is empty by the toner in the supplied toner tank can be executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developing device having a toner empty mechanism.

[Conventional technology]

Conventionally, this type of developing device only issues a toner empty warning when the toner is empty, or issues a warning before the toner becomes empty and guarantees printing until the toner becomes completely empty. It was of a structure that

[Problem to be solved by the invention]

However, since the above method does not guarantee printing after the toner is empty, it is assumed that the user always carries consumables such as toner or EP cartridges.

If you want to detect toner empty and simply issue a warning,
Since there is no guaranteed number of subsequent prints, if the user does not have replacement consumables, he or she must judge by himself whether or not he can continue printing by looking at the print. Also, when toner near-end is detected and there is a guaranteed number of sheets, there are no consumables.

The device stops when the guaranteed number of sheets is reached, which is inconvenient for the user.

In other words, if the toner becomes empty, there is a drawback that it is not possible to follow up on the user's usage until the purchase of consumables unless the guaranteed number of toner sheets is about one hopper after that.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide a developing device that guarantees printing after toner empty.

[Means to solve the problem]

In order to achieve the above objects, the developing device having a mechanism for detecting toner empty according to the present invention is equipped with a toner sub-tank mechanism for replenishing toner for the guaranteed number of sheets to be printed in order to guarantee printing after toner empty detection. It is something.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing one embodiment of the present invention.

In the figure, 7 is a drum (OPC) whose surface is charged by a main charger 8, and the charged surface of the drum 7 is irradiated with light to form an electrostatic latent image. The developing section, which attaches toner to the electrostatic latent image on the drum 7 and develops it into a visible image, uses a funnel-shaped inner wall surface with an angle approximately equal to the toner's angle of repose to supply the toner downward by falling under its own weight. a sleeve 6 for supplying toner to the drum 7; a doctor blade 12 for regulating the amount of toner adhering to the sleeve 6;
It consists of mixers 4 and 5 that convey the toner in the toner tank 2 to the sleeve 6.

The waste toner cartridge includes a toner box 10 that stores waste toner, and a scraping blade 9 that scrapes off residual toner on the drum 7. 1 is a cover.

Therefore, the toner conveyed to the sleeve 6 is regulated by the doctor blade 12 and adheres to the surface of the drum 7 to develop the latent image into a visible image. On the other hand, excess toner remaining on the drum 7 is scraped off by the blade 9 and collected into the toner box 10. Furthermore, toner empty is detected based on a change in the torque of the mixer 4.

In the present invention, a toner sub-tank 3 filled with toner for the number of sheets guaranteed to be printed is installed in a part of the toner tank 2 to ensure printing after toner empty detection, and the replenishment port 3a of the toner sub-tank 3 is connected to the film 11. It is sealed. Therefore, when toner empty is detected due to a change in the torque of the mixer 4, the film 11 is peeled off, toner is replenished from the toner sub-tank 3 into the toner tank 2, and the toner in the toner tank 2 is filled with the toner. Printing is guaranteed after empty detection. The user purchases toner or an EP cartridge within a period during which printing with the supplied toner is guaranteed, and prepares to replenish the toner by the time the toner empty status of the toner is detected.

〔Effect of the invention〕

As explained above, according to the present invention, in order to guarantee printing during the period from when the toner is empty to when the toner is refilled, even when there are no consumables on hand and it takes time to purchase them,
This has the effect that printing can be guaranteed until toner is replenished, and management is easy for the user.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention. 1...Cover 2...Toner tank 3
...Toner sub tank 4, 5...Mixer 6...
- Sleeve 7... Drum 8... Main charger 9... Scraping blade lO... Toner box 11... Film 12... Doctor blade Figure 1

Claims (1)

[Claims] 1. A developing device having a mechanism for detecting toner empty, characterized in that the developing device is equipped with a toner sub-tank mechanism for replenishing toner for the number of sheets guaranteed to be printed in order to guarantee printing after toner empty detection.