JPH0245879Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a toner recycling device for a copying machine using one-component toner.

(Prior art) In some conventional toner recycling devices for copying machines, the discharged toner simply falls into the center of the developing unit or its vicinity through a recycling pipe, but the toner concentration in the falling area is low due to insufficient agitation. This has the disadvantage that background stains occur on the copy corresponding to that position, significantly degrading the image quality.

Therefore, even those in which small mixing is performed once within the developing unit have the drawback that the mechanism is complicated and expensive.

(Purpose) The purpose of the present invention is to use a simple structure to improve the agitation between the waste toner and the circulating toner that falls into the developing unit, eliminate background stains, and obtain excellent image quality.

(Structure) The structure of the present invention will be explained according to an embodiment shown in the attached drawings. 1 is a photoreceptor drum that rotates in the direction of the arrow, and on its outer periphery are an eraser 2, a charger 3,
A static elimination lamp 4, a cleaning unit 5, a conveyor belt 6, a transfer charger 7, a separation charger 8, a registration roller 9, and a developing unit 10 are provided. Reference numeral 11 denotes a discharge pipe for discharging toner from the cleaning unit 5, and a discharge coil 12 is interposed therein. Reference numeral 13 denotes a recycling pipe, one end of which communicates with the discharge pipe 11, the other end of which is disposed within the developing unit 10, and a discharge coil 14 that is driven in conjunction with the main body drive section is interposed inside. The toner 16 stirred by the developing agitator 15 is transferred to the developing sleeve 1 by the paddle wheel 17.
8 and is regulated to a constant amount by a doctor 19, and the regulated toner flows back to the agitator 15 via the partition plate 20. A drop hole 21 is provided in the partition plate 20, a circulating toner inlet 22 is provided on the upper surface of the recycle pipe 13 located below the drop hole 21, and a large number of discharge holes 23 are provided below the tip of the recycle pipe 13. 24 is a cleaning blade, and 25 is a toner tank.

Next, the effect will be explained. The discharged toner removed from the photoreceptor drum 1 by the cleaning blade 24 is transferred to the discharge pipe 11 by the discharge coil 12.
The discharge coil 14 in the recycle pipe 13 is further fed into the recycle pipe 13.
The liquid is agitated and fed to the tip. The recirculated toner flows into the tip of the recycle pipe 13 from the drop hole 21 of the partition plate 20, and the recirculated toner and discharged toner are mixed and stirred and fall into the developing unit 10 from the discharge hole 23, and as described above, the recirculated toner flows into the developing sleeve 18.
is supplied to

(Effects) According to the present invention, in a copying machine that has a cleaning unit that cleans residual toner on the photoconductor and a recycling mechanism that sends the discharged toner collected by the cleaning unit into the developing unit, one end of the recycling pipe can be closed. Connects to the toner discharge pipe of the cleaning unit,
The other end is disposed inside the developing unit, a discharge coil that is driven in conjunction with the main body drive section is interposed inside the recycling pipe, and an inlet for circulating toner inside the developing device is provided on the top surface of the recycling pipe. Since a large number of discharge holes are provided below the tip of the recycling pipe, the simple structure improves the agitation between the discharged toner that falls into the developing unit and the circulating toner, eliminates background stains, and provides excellent image quality. Can be done.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of the present invention, Fig. 2 is an enlarged front sectional view of the main parts of the developing unit shown in Fig. 1, and Fig. 3 is an enlarged side sectional view of the main parts of the cleaning unit and developing unit shown in Fig. 1. , FIG. 4 is an enlarged plan view of the partition plate of FIG. 1. DESCRIPTION OF SYMBOLS 1... Photoreceptor drum, 5... Cleaning unit, 10... Developing unit, 11... Discharge pipe, 1
3... Recycle pipe, 12, 14... Discharge coil, 20... Partition plate, 21... Drop hole, 22... Circulation toner inlet, 23... Discharge hole.

Claims (1)

[Scope of utility model registration request] In a copying machine that has a cleaning unit that cleans residual toner on the photoconductor and a recycling mechanism that sends the discharged toner collected by the cleaning unit into the developing unit, one end of the recycling pipe is connected to the cleaning unit for discharging the discharged toner. It communicates with the pipe, and the other end is disposed inside the developing unit, and a discharge coil that is driven in conjunction with the main body drive unit is interposed inside the recycle pipe. A toner recycling device for copying machines that has a toner inlet and numerous discharge holes below the tip of the recycling pipe.