Toner supplying method, toner supplying device, developing device, and image forming apparatus

Abstract

A toner supplying device includes: a toner density sensor for detecting a density of toner contained in a developer tank; a toner hopper for supplying toner to the developer tank; a toner cartridge for supplying toner to the toner hopper; and a control section, when a request to supply toner to the developer tank is made in accordance with a signal detected by the toner density sensor, for controlling a hopper driving motor and a cartridge driving motor so that (i) the toner hopper supplies toner to the developer tank and (ii) the toner cartridge supplies toner to the toner hopper. Thus, in a structure having first and second toner supplying sections disposed on top of each other, toner can be stably supplied to a developer tank.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pattern diagram showing a developing device including a toner supplying device according to an embodiment of the present invention.

FIG. 2 is a front view showing an inner structure of a printer including the developing device shown in FIG. 1.

FIG. 3 is a perspective view of the developing device shown in FIG. 1.

FIG. 4 is a perspective view of a toner hopper shown in FIG. 1.

FIG. 5 is a cross-sectional view taken along the arrow H-H of FIG. 4.

FIG. 6 is a cross-sectional view taken along the arrow I-I of FIG. 4.

FIG. 7 is a cross-sectional view taken along the arrow J-J of FIG. 4.

FIG. 8 is a perspective view of a toner transporting screw of the toner hopper shown in FIG. 4.

FIG. 9( a) is a perspective view of a pipe portion of a supplying pipe shown in FIG. 1.

FIG. 9 (b) is a longitudinal sectional view of the pipe portion shown in FIG. 9(a).

FIG. 10 is a block diagram showing an arrangement of a control device of the toner supplying device shown in FIG. 1.

FIG. 11 is a graph showing a relationship between (i) the toner cartridge driving time during which a toner cartridge shown in FIG. 3 is driven, and (ii) the amount of toner remaining in the toner cartridge.

FIG. 12 is a timing chart showing an example of control operation carried out with respect the toner supplying device by the control device shown in FIG. 10.

FIG. 13 is a timing chart showing a control operation carried out by the control device in cases where a remaining toner amount sensor always indicates “Low”, in the example shown in FIG. 12.

FIG. 14 is a timing chart showing a control operation carried out by the control device in cases where the remaining toner amount sensor always indicates “High”, in the example shown in FIG. 12.

FIG. 15 is a timing chart showing another example of control operation carried out with respect to the toner supplying device by the control device shown in FIG. 10.

FIG. 16 is a timing chart showing another example of control operation carried out with respect to the toner supplying device by the control device shown in FIG. 10.

FIG. 17( a) is a side view of the toner cartridge shown in FIG. 3.

FIG. 17( b) is a perspective view of the toner cartridge shown in FIG. 3.

FIG. 18 is a side view of a top end portion of a toner bottle, shown in FIG. 17(a), which is provided in the toner cartridge.

FIG. 19 is a side view illustrating that a scraper is mounted in the toner bottle's top end portion shown in FIG. 18.

FIG. 20 is a front view of the toner bottle shown in FIG. 19.

FIG. 21 is a perspective view of a lower surface of a bottle supporting member shown in FIGS. 17(a) and 17(b).

FIG. 22( a) is a perspective view of a first housing constituting the bottle supporting member shown in FIG. 21.

FIG. 22( b) is a perspective view of a second housing constituting the bottle supporting member shown in FIG. 21.

FIG. 23 is an explanatory diagram showing a relationship between (i) a toner discharging chamber of the toner supporting member shown in FIG. 21 and (ii) a location where the scraper of the toner bottle is provided.

FIG. 24 is a schematic longitudinal sectional view of the toner bottle's top end portion shown in FIG. 19.

FIG. 25 is a schematic longitudinal sectional view illustrating that the bottle supporting member is attached to the toner bottle's top end portion shown in FIG. 19.

FIG. 26( a) is an explanatory diagram showing a state in which a shutter member is open in the toner cartridge shown in FIGS. 17(a) and 17(b).

FIG. 26( b) is an explanatory diagram showing a state in which the shutter member is closed in the toner cartridge shown in FIGS. 17(a) and 17(b).

Claims

1. A toner supplying device, comprising: a toner density sensor for detecting a toner density in a developer tank;first toner supplying means for supplying toner to the developer tank;second toner supplying means for supplying toner to the first toner supplying means; andcontrol means, when a request to supply toner to the developer tank is made in accordance with a signal detected by the toner density sensor, for controlling the first toner supplying means and the second toner supplying means so that (i) the first toner supplying means supplies toner to the developer tank and (ii) the second toner supplying means supplies toner to the first toner supplying means.

2. The toner supplying device as set forth in claim 1, wherein the first toner supplying means includes (i) a toner inlet via which toner is supplied from the second toner supplying means, (ii) a toner outlet via which the toner to be supplied to the first supplying means is discharged, (iii) a toner transportation path, provided in a direction so as to cross a vertical direction, which extends from the toner inlet to the toner outlet, and (iv) a toner transporting member, provided in the toner transportation path, which sequentially transports toner, dropped onto the toner transportation path via the toner inlet, to cause the toner to drop via the toner outlet.

3. The toner supplying device as set forth in claim 2, wherein the toner transporting member is a toner transporting screw which is rotated to stir and transport the toner.

4. The toner supplying device as set forth in claim 1, further comprising: display means for carrying out a display;display control means for controlling the display means; andremaining toner amount detecting means for detecting a remaining toner amount in the first toner supplying means,the second toner supplying means including a toner cartridge, andwhen the remaining toner amount detecting means has detected for a certain period of time or longer a shortage in remaining toner amount, the display control means controlling the display means to carry out a display suggesting replacement of the toner cartridge.

5. A developing device, comprising a toner supplying device as set forth in claim 1.

6. An image forming apparatus, comprising a developing device as set forth in claim 5.

7. A toner supplying device, comprising: a toner density sensor for detecting a toner density in a developer tank;first toner supplying means for supplying toner to the developer tank;second toner supplying means for supplying toner to the first toner supplying means; andcontrol means for controlling the first toner supplying means and the second toner supplying means so that (i) the first toner supplying means supplies toner to the developer tank when a request to supply toner to the developer tank is made in accordance with a signal detected by the toner density sensor and (ii) the second toner supplying means supplies toner to the first toner supplying means when a supply of toner by the first toner supplying means to the developer tank is detected.

8. The toner supplying device as set forth in claim 7, wherein the control means (a) integrates time during which the first toner supplying means is supplying toner to the developer tank and (b) causes, every time the time thus integrated reaches a first set time, the second toner supplying means to supply toner to the first toner supplying means.

9. The toner supplying device as set forth in claim 7, wherein the first toner supplying means includes (i) a toner inlet via which toner is supplied from the second toner supplying means, (ii) a toner outlet via which the toner to be supplied to the first supplying means is discharged, (iii) a toner transportation path, provided in a direction so as to cross a vertical direction, which extends from the toner inlet to the toner outlet, and (iv) a toner transporting member, provided in the toner transportation path, which sequentially transports toner, dropped onto the toner transportation path via the toner inlet, to cause the toner to drop via the toner outlet.

10. The toner supplying device as set forth in claim 7, wherein: the control means (a) integrates time during which the first toner supplying means is supplying toner to the developer tank and (b) causes, every time the time thus integrated reaches a first set time, the second toner supplying means to supply toner to the first toner supplying means;the first toner supplying means includes (i) a toner inlet via which toner is supplied from the second toner supplying means, (ii) a toner outlet via which the toner to be supplied to the first supplying means is discharged, (iii) a toner transportation path, provided in a direction so as to cross a vertical direction, which extends from the toner inlet to the toner outlet, and (iv) a toner transporting member, provided in the toner transportation path, which sequentially transports toner, dropped onto the toner transportation path via the toner inlet, to cause the toner to drop via the toner outlet; andthe first set time is set in accordance with time required for the toner transporting member to transport toner outward a region, which is located directly below the toner inlet, in the toner transportation path of the first toner supplying means.

11. The toner supplying device as set forth in claim 9, wherein the second toner supplying means includes a toner bottle, containing toner therein, which is rotated to discharge the toner.

12. The toner supplying device as set forth in claim 9, further comprising: a supplying pipe, extending in an up-and-down direction, which has (i) one end connected to the toner outlet of the first toner supplying means and (ii) another end connected to the developer tank.

13. The toner supplying device as set forth in claim 7, further comprising: display means for carrying out a display;display control means for controlling the display means; andremaining toner amount detecting means for detecting a remaining toner amount in the first toner supplying means,the second toner supplying means including a toner cartridge, andwhen the remaining toner amount detecting means has detected for a certain period of time or longer a shortage in remaining toner amount, the display control means controlling the display means to carry out a display suggesting replacement of the toner cartridge.

14. A developing device, comprising a toner supplying device as set forth in claim 7.

15. An image forming apparatus, comprising a developing device as set forth in claim 14.

16. A method for supplying toner from first toner supplying means to a developer tank, and for supplying toner from second toner supplying means to the first toner supplying means, the method, comprising the step of:when a shortage in toner density in the developer tank is detected, (i) causing the first toner supplying means to supply toner to the developer tank and (ii) causing the second toner supplying means to supply toner to the first toner supplying means.

17. A method for supplying toner from first toner supplying means to a developer tank, and for supplying toner from second toner supplying means to the first toner supplying means, the method, comprising the steps of:when a shortage in toner density in the developer tank is detected, causing the first toner supplying means to supply toner to the developer tank; andwhen a supply of toner by the first toner supplying means to the developer tank is detected, causing the second toner supplying means to supply toner to the first toner supplying means.