JP2001042716A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To treat waste toner without contaminating hands by providing a heating source in a waste toner recovery device, then melting and solidifying the recovered toner in the recovery device. SOLUTION: A cleaning device 24 recovers the toner 18b remaining on the surface of a photoreceptor drum 12 after a toner image is transferred by a transfer roller 20. The recovered toner 18b is accumulated at a part where a stirring screw 24d is provided. A housing 24b for housing combustible material 24e such as a chip of wood, a slip of paper and paper powder and the like is provided at the upper part inside the device 24, and the material 24e freely drops while a shutter 24c is opened and closed. The waste toner 18b and the material 24e are stirred by the screw 24d and the mixture of the waste toner 18b and the material 24e drops into a solidifying bottle 24h. The bottle 24h is heated by radiant heat from a fixing heating roller 22a, whereby the temperature of the waste toner 18b is raised to glass transition point temperature, for example, 60 to 70 deg.C, and the waste toner 18b is melted, and then cooled and solidified.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus,
In particular, copiers, facsimiles, and electrophotographic processes that use an electrophotographic process of transferring a toner image on a toner image holding member to a transfer material.
The present invention relates to an image forming apparatus such as a printer or a multifunction peripheral thereof.

[0002]

2. Description of the Related Art In this type of conventional image forming apparatus, every time a toner image is transferred from a toner image holding member to a transfer material such as paper, a small amount of toner cannot be prevented from remaining on the holding member. . If the next image forming process is performed while leaving the residual toner as it is, it is inevitable that the image quality will deteriorate. Therefore, the residual toner is generally removed from the holding member after the transfer.

[0003] The toner is removed from the holding member by a cleaning means such as a cleaning blade or a fur brush, is stored in a container attached to the cleaning means, is further conveyed to a waste toner container, is stored in the waste toner container. 2. Description of the Related Art An image forming apparatus which is disposed in a container or transferred to a waste toner bottle when it is full and is disposed of is widely used.

[0004] On the other hand, with the recent heightened awareness of environmental protection, there is room for improvement in the conventional disposal method in which waste toner is buried in a waste toner container or a cleaner unit in a state of being filled or burnt.

[0005] In the first place, most of the toner used in the electrophotographic process is a resin component having a powder of 5 to 10 microns, but since a small amount of an inorganic component adheres to the surface,
Pure material cannot be recycled for toner, and even if it tries to burn as powder, the calorie is high,
In addition, since the powder is a powder, steady combustion is difficult, which causes problems such as easily damaging the combustion furnace and the kettle.

[0006]

One method for solving such a problem is disclosed in Japanese Patent Laid-Open No. 5-295375 [C1.
0L 5/00, B09B 3/00, G03G 21
/ 00]. The technique proposed here is to mix the waste toner with combustibles such as wood chips to produce a solidified solid fuel.

However, in the technology described in this publication, it is necessary to provide a special facility for solidifying the waste toner, a heater, and a mechanism accompanying the heater, which may cause a problem in cost. In addition, it is necessary to take out the waste toner from the image forming apparatus and carry it to such a facility, so that another device for preventing scattering of the waste toner during that time is required.

[0008] Therefore, a main object of the present invention is to provide a novel image forming apparatus which can solve the above-mentioned problems by solidifying waste toner in the image forming apparatus.

[0009]

According to the present invention, there is provided a toner collecting device for transferring a toner image formed on a toner image holding member to a transfer material and collecting toner remaining on the toner image holding member. In the image forming apparatus, a heating source for applying heat to the waste toner collecting device is provided, and the collected toner is melted and solidified in the toner collecting device.

[0010]

The waste toner is melted by mixing the waste toner collected in the toner recovery device with the combustible material, for example, by heating to or near the glass transition temperature of the waste toner, and thereafter cooling the waste toner. As a result, the waste toner is solidified. Therefore, the user can perform the waste toner processing without removing his / her hands by removing the solid matter.

In the case where the image forming apparatus further includes a heating and fixing unit for heating and fixing the toner image transferred to the transfer material, the fixing unit is disposed by disposing the waste toner collecting device near the fixing unit. Can be used as a heating source. In this case, another heat source is unnecessary, and there is no significant cost increase.

However, when the heat fixing means includes a fixing roller, it is necessary to rotate the fixing roller during the solidification. This is to prevent the deterioration of the fixing roller.

In the embodiment, there is further provided an instruction means for instructing execution of the toner melting and solidifying step, and the toner melting and solidifying step is executed in accordance with the instruction of the instruction means. The instruction means includes a solidification instruction key provided on the operation panel and a toner amount detection means for detecting the amount of toner collected by the toner collection device. The toner amount detecting means may be a counter that counts the number of times the image forming process has been performed, or may be a sensor such as a photo sensor that detects the amount of toner stored in the toner collecting device. .

When the heat of the heat fixing means is used in the melting and solidifying step, the toner melting and solidifying step is performed after the image forming process is performed. This is because the thermal stability of the fixing unit and the recovery device was considered.

The above-described combustible material may be stored in a combustible material storage section provided in the toner collecting device, and the combustible material may be supplied from the combustible material as needed. Waste toner solidified by mixing a combustible material can be used as a solid fuel.

Furthermore, a stirring means for mixing the combustible material and the collected toner may be provided.

In order to maintain the temperature at or near the glass transition temperature, a temperature control means for controlling the temperature in the toner melting and solidifying step is further provided.

[0018]

According to the present invention, the waste toner is melted and solidified in the image forming apparatus. Therefore, compared to solidifying the powdery waste toner in another place, environmental pollution due to scattering and scattering is reduced. Almost completely prevented.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0020]

Referring to FIG. 1, an image forming apparatus 10 of this embodiment includes a photosensitive drum 12 as an image carrier, and the photosensitive drum 12 is provided substantially at the center of the main body of the image forming apparatus 10. A charger 14 is provided above the photoconductor drum 12, and an exposure device 16 is provided diagonally above and to the right of the photoconductor drum 12. Therefore, the surface of the photosensitive drum 12 is uniformly charged by the charger 14, and the uniformly charged surface is irradiated with laser light corresponding to desired information. Therefore, an electrostatic latent image is formed on the surface of the photosensitive drum 12.

A developing device 18 is provided on the right side of the photosensitive drum 12, and the developing device 18 includes a developing roller 18a and a toner 18b. The developing roller 18a is provided so as to be in contact with the surface of the photosensitive drum 12, and is provided with a toner 18b.
Is supplied to the photosensitive drum 12. That is, the toner 18 b is attached to the electrostatic latent image, and a toner image is formed on the surface of the photosensitive drum 12. The toner 18b is composed of a binder resin (binder resin), a colorant (carbon black, dye, etc.) and a compounding agent. Known resins can be used as the binder resin, and charge control agents, release agents, magnetic powders, and the like can be used as compounding agents.

The image forming apparatus 10 also includes a transfer roller 20
And the transfer roller 20 is provided so as to be in contact with the lower part of the photosensitive drum 12. With this transfer roller 20,
The toner image formed on the surface of the photosensitive drum 12 is transferred to a sheet (transfer material: not shown) fed and conveyed.

Further, the image forming apparatus 10 includes fixing rollers 22 a and 22 disposed downstream of the transfer roller 20.
b, and the fixing rollers 22a and 22b cooperate to constitute a heating / pressing type fixing means. Although not shown, the heat source is provided to the fixing roller 22a, so that the fixing roller 22a functions as a pressure heating roller and the fixing roller 22b functions as a pressure roller. Then, the toner image is permanently fixed on a sheet as a transfer material, and the image forming apparatus 10
Is discharged from

Further, the image forming apparatus 10 includes a cleaning device 24, a temperature detector 26, and a fan 28. A cleaning device 24, which is a toner collecting device, is provided on the left side of the photosensitive drum 12.
The rubber blade 24a provided on the photosensitive drum 12 is disposed in contact with the surface of the photosensitive drum 12. Cleaning device 24
Is the toner (residual toner) 1 remaining on the surface of the photosensitive drum 12 after the transfer of the toner image by the transfer roller 20.
8b is collected. That is, the residual toner 18b is scraped off by the rubber blade 24a and collected from the side surface of the cleaning device 24.

Recovered residual toner (recovered toner) 18
b is stored in a portion of the cleaning device 24 where the stirring screw 24d is provided. As shown in FIG. 2, the stirring screw 24d is formed to extend in the longitudinal direction of the cleaning device 24. In addition, a housing 24b for accommodating a combustible material 24e such as wood chips, paper chips, and paper dust is provided at an upper portion in the cleaning device 24, and a supply port 24f for supplying the combustible material 24e is provided at a bottom surface of the housing 24b. Can be A shutter 2 for opening and closing the supply port 24f is provided.
4c is provided. In FIG. 2, the stirring screw 24
In order to clearly show d, the housing 24b and the shutter 24c are omitted.

While opening and closing the shutter 24c, the flammable material 2
4e falls freely and is supplied to the portion provided with the stirring screw 24d. Subsequently, the recovered toner 18b and the combustible material 24e are stirred by the stirring screw 24d.
Therefore, the collected toner 18b and the combustible material 24e are uniformly contacted.

Further, the cleaning device 24 is provided with a disposal port for discarding the collected toner 18b, and a solidification bottle 24h is detachably attached to the disposal port.
Then, the collected toner 18 is stirred by the stirring screw 24d.
b and the combustible material 24e are stirred and mixed, and the stirred and mixed recovered toner 18b and the combustible material 24e are conveyed toward the waste port. Therefore, the mixture of the waste toner 18b and the combustible material 24e falls into the solidified bottle 24h. As will be described later in detail, the mixture toner 18b dropped into the solidification bottle 24h is heated together with the combustible material 24e to be melted and solidified. Therefore, if the solidification bottle 24h is removed after the waste toner 18b has been melted and solidified, the solidified waste toner 18b can be taken out without soiling the hands. However, combustible material 24e
Does not actively promote the melting of the waste toner 18b, but improves the flammability when the solidified waste toner 18b is used as fuel.

In order to melt and solidify the waste toner 18b in the solidification bottle 24h, it is necessary to heat the bottle 24h. For this purpose, in this embodiment, the solidified bottle 24h is arranged near the fixing roller 22a. That is, in this embodiment, the fixing roller 22a is used as a heat source for melting and solidifying. Then, the heating roller 22a
When the solidified bottle 24h is heated by radiant heat from the waste toner 18b, the waste toner 18b is heated to a glass transition point temperature, for example, 6 ° C.
The temperature is raised to 0-70 ° C. Therefore, the toner 18b
Is melted and then cooled (natural cooling or air cooling)
The toner 18b is solidified.

As described above, since the solidified bottle 24h has a relatively high temperature, it is desirable that the solidified bottle 24h be made of a material having heat resistance and not generating harmful substances such as dioxin by heating.

For the above-mentioned temperature control, a temperature detector 2 is provided near the cleaning device 24, ie, the solidified bottle 24h.
8 and a fan 28 are provided. The temperature detector 28 detects the temperature of the lower portion of the cleaning device 24, that is, the temperature of the solidified bottle 24h. The fan 28 is turned on / off according to the detected temperature, and the solidified bottle 24h
Is maintained near the above-mentioned glass transition temperature.
More specifically, when the temperature inside the bottle 24h becomes higher than a certain temperature (for example, the first temperature), the fan 28 is turned on, and the amount of heat released from the heating roller 22a to the solidified bottle 24h is increased. The temperature inside the bottle drops. On the other hand, when the temperature inside the solidification bottle 24h is lower than a certain temperature (for example, the second temperature), the fan 28
Turn off to minimize heat escape and increase temperature. As described above, using the heat of the fixing unit as a heat source for melting and solidifying the toner is preferable in terms of power saving as compared with a case where a special heater is provided.

If the temperature of the solidification bottle 24h cannot be raised to the glass transition temperature of the toner 18b only by the residual heat from the fixing means, as shown by a dotted line in FIG. Heater 3
0 may be provided near the solidification bottle 24h.
In addition, the cleaning device 2 includes only the heater 30.
The lower part of 4, ie, the solidified bottle 24h may be heated. In this case, although the power consumption is increased, it is not necessary to dispose the solidified bottle 24h near the fixing roller 22a, so that the degree of freedom in disposing the components is improved. Further, the combustible material 24 mixed with the waste toner 18b
The firing point temperature of e is naturally higher than the glass transition point temperature of the waste toner 18b.
e does not ignite.

Further, the cleaning device 24 is provided with a photo sensor 24g.
It is detected that a certain amount of waste toner 18b is stored in the cleaning device 24. The photo sensor 24g outputs a high-level signal when receiving light from a light-emitting unit (not shown), and outputs a low-level signal when not receiving light from the light-emitting unit. That is, when the light from the light emitting unit is not received, the light is blocked by the collected toner 18b, so that a certain amount of the toner 18b in the cleaning device 24 is stored up to the position where the photo sensor 24g is provided. You can see that. When the toner amount sensor 24g detects a certain amount of toner 18b, a solidification routine shown in FIG. 5 described later can be automatically executed.

FIG. 3 shows an electrical circuit diagram of such an image forming apparatus 10. That is, the image forming apparatus 10
The CPU 40 includes a PU 40, and is connected to the operation panel 42 and to a print control circuit 46 and a buffer memory 48 via a bus 44. Further, the print control circuit 46 includes the electric charger 14, the exposure device 16, the fixing roller 24,
Shutter 24c, photo sensor 24g, temperature detector 2
6, connected to the fan 28, the heater 30, and the motor 50. The motor 50 is for driving the stirring screw 24d to rotate. A main motor (not shown) for driving the photosensitive drum 12, the transfer roller 20, the fixing roller 22, and the like, which are driven to rotate during development, is provided. Provided separately.

When the operator gives an instruction such as printing using a start button (not shown) on the operation panel 42, the CPU 40 gives an instruction to the print control circuit 46 in response to the instruction, and the above circuit is controlled. The detection result of each detector is CP
Provided to U40. Further, data corresponding to an image or a character transmitted from the host is temporarily stored in the buffer memory 48, read out according to an instruction from the CPU 40, and data (toner data) of laser light for forming an electrostatic latent image. And the print control circuit 40
Is provided to the exposure device 16 through

The operation panel 42 is provided with a solidification command key 42a so that the process of melting and solidifying the waste toner 18b can be performed at an arbitrary timing. That is, when the key 42a is operated, the CPU 40 detects the operation, and the CPU 40 executes the solidification routine shown in FIG.

However, in order to automatically melt and solidify the waste toner 18b when necessary, the counter 4
0a may be used. That is, the CPU 40 includes a counter 40a, and the counter 40a counts the number of executions of the image forming process. That is, the CPU 40 can know the number of developments by the count value of the counter 40a, and when the number of image forming processes reaches a predetermined number (for example, 1000 in this embodiment), the CPU 40 automatically executes the solidification routine of FIG. Execute. In that sense, the counter 40a is also a toner amount detecting unit.

In an image forming apparatus in which a density detecting patch is formed on the photosensitive member 12, the toner density is detected by an optical sensor, and a developing bias is determined according to the density, the toner of the patch portion is transferred. It is left on the photoconductor 12 without being changed. Since the amount of toner in the patch portion is substantially constant, the amount of waste toner can be detected almost accurately by counting the number of image forming processes by the counter 40a as described above. Therefore, in this case, the above-described toner amount sensor or photo sensor 24g can be omitted.

The CPU 40 is further provided with a timer 40b for controlling the time for executing the solidification routine. That is, the solidification routine of FIG. 5 continues for the time specified by the timer 40b. However, the time of the timer 40b is set in accordance with the result experimentally obtained at the initial manufacturing stage, but can be appropriately changed according to the subsequent use situation.

When the start button on the operation panel 42 is pressed, a routine shown in FIG. 4 is executed. In the first step S1 of this routine, an image forming process is executed according to a well-known procedure. Then, in step S2,
The counter 40a described above is incremented. That is, the counter 40a counts the number of executions of the image forming process.

In step S3, it is determined whether there is a next page. If there is another page, the process returns to step S1. If not, in step S4, whether the counter 40a has counted a predetermined value, that is, the cleaning device 24 It is determined whether or not a predetermined amount of waste toner 18b is stored therein. If "NO" is determined in the step S4, it is next determined in a step S5 whether the waste toner 18b is a predetermined amount. That is, it is determined whether a detection signal is input from the photo sensor 24g. If “NO” is determined in the step S5, in a step S6, the CP
U40 determines whether or not the solidification command key 42a of the operation panel 42 has been operated. When detecting that this key operation has been performed, the CPU 40 sets a key operation flag (not shown) formed in the memory 40c. Therefore, in this step S6, it is determined whether or not the key operation flag is "1".

After the image forming process is executed in step S1 in this manner, steps S4, S5 and S6
In, the CPU 40 determines whether or not it is time to melt and solidify the waste toner 18b. If "YES" is determined in any of steps S4 to S6, a waste toner solidification routine shown as step S7 is executed. If "NO" is determined in all the determination steps, the process is terminated.

From the viewpoint of energy saving, the solidification process of the waste toner 18b is desirably executed when the temperature in the vicinity of the fixing means and the cleaning device is in a raised state and the temperature is relatively stable. . Therefore, in this embodiment, even if the solidification command key 42a is operated at an arbitrary timing by the user, the processing is waited until the next image forming process is completed so that the solidification step can be executed after the image forming process is executed. I have decided.

However, when the solidification command key 42a is operated, it is needless to say that the solidification routine can be executed according to the key operation even after the execution of the image forming process.

First step S7 of the solidification routine of FIG.
At 1, the CPU 40 opens the shutter 24c. Depending on,
The combustible material 24e (FIG. 1) in the housing 24b falls. At the same time, in step S72, the motor 50 is turned on to rotate the stirring screw 24d. Therefore,
As described above, the waste toner 18b and the combustible material 24e are mixed well and transferred to the solidification bottle 24h.

Next, the CPU 40 controls the fixing roller 22a.
Raise the temperature of. That is, since the melting temperature of the waste toner 18b needs to be higher than the temperature of the fixing roller 22a during a normal image forming process, the temperature of the fixing roller 22a is increased in step S73.
Although not shown in FIG. 5, the fixing rollers 22a and 22b are rotated at this time. This is because if the fixing rollers 22a and 22b are heated to a high temperature without rotating,
This is because there is a possibility that the pressure contact portion of the two rollers partially becomes high temperature and deteriorates. The reason for setting the melting and solidifying temperature higher than the temperature in a normal image forming process is to prevent the toner from solidifying in a normal use state.

Thereafter, the temperature control shown in steps S74 to S77 is executed. That is, it is determined in step S74 whether or not the temperature detected by the temperature detector 26 is equal to or higher than the first temperature, for example, 70 ° C. If “YES”, the fan 28 is turned on and cooled in step S75. Conversely, it is determined in step S76 whether the temperature detected by the temperature detector 26 is equal to or lower than the second temperature, for example, 60 ° C. If “YES”, the fan 28 is turned off in step S77 to stop cooling. By doing so, the temperature of the solidified bottle 24h can be maintained at or near the glass transition temperature of the waste toner 18b. However, since the temperature sensor 26 does not directly detect the temperature in the solidified bottle 24h, the above-described specific temperature can be changed as appropriate. Further, it goes without saying that the specific temperature control range changes in accordance with the physical properties (glass transition temperature) of the toner 18b.

In the last step S78, it is determined whether or not the timer 40b triggered at the start of this routine has counted a predetermined time, for example, 5 minutes.
This time is a time required for melting and solidifying the waste toner 18b, and this time can also be arbitrarily changed. Step S7
If "YES" is determined in 8, the solidification routine ends. However, if "NO", the process returns to step S74 to continue the temperature management.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is a perspective view showing the cleaning device shown in FIG. 1 embodiment.

FIG. 3 is an electrical circuit diagram of the image forming apparatus shown in FIG.

FIG. 4 is a flowchart showing the operation of the embodiment in FIG. 1;

FIG. 5 is a flowchart showing a solidification routine shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus 12 ... Photoreceptor drum 22a, 22b ... Fixing roller 24 ... Cleaning device 24b ... Housing 24c ... Shutter 24d ... Stirring screw 24e ... Combustible material 24g ... Photosensor 24h ... Solidified bottle 26 ... Temperature detector 28 ... Fan 30 ... heater 40 ... CPU 42 ... operation panel 42a ... solidification command key

Claims (13)

[Claims] 1. An image forming apparatus comprising: a toner collecting device for transferring a toner image formed on a toner image holding member to a transfer material and collecting toner remaining on the toner image holding member; An image forming apparatus, wherein a heat source for applying heat is provided in the collecting device, and the collected toner is melted and solidified in the toner collecting device. 2. The image forming apparatus according to claim 1, further comprising a fixing unit configured to heat and fix the toner image transferred to the transfer material, wherein the waste toner collecting device is disposed near the fixing unit.
The fixing means was used as the heating source,
The image forming apparatus according to claim 1. 3. The image forming apparatus according to claim 2, wherein the fixing unit includes a fixing roller, and the fixing roller is rotated during the melting and solidification. 4. The method of claim 1, wherein said heating source includes another heater.
4. The image forming apparatus according to any one of claims 1 to 3. 5. The image forming apparatus according to claim 1, further comprising an instruction unit for instructing execution of the toner fusion and solidification step, and executing the toner fusion and solidification step in accordance with the instruction of the instruction unit. . 6. The image forming apparatus according to claim 5, wherein said instruction means includes a solidification instruction key provided on an operation panel. 7. An image forming apparatus according to claim 5, wherein said instruction means includes a toner amount detecting means for detecting an amount of toner collected by said toner collecting device. 8. An image forming apparatus according to claim 7, wherein said toner amount detecting means includes a counter for counting the number of executions of the image forming process. 9. The image forming apparatus according to claim 7, wherein said toner amount detecting means includes a sensor for detecting an amount of toner stored in said toner collecting device. 10. The image forming apparatus according to claim 2, wherein the toner melting and solidifying step is performed after the image forming process is performed. 11. The image forming apparatus according to claim 1, further comprising a combustible material storage section for storing a combustible material for mixing with the collected toner in the toner collection device. 12. The image forming apparatus according to claim 11, further comprising stirring means for mixing said combustible material and said collected toner. 13. The image forming apparatus according to claim 1, further comprising a temperature control unit for controlling a temperature in the toner melting and solidifying step.