JP2021162807A - Image forming apparatus - Google Patents

Abstract

To provide an image forming apparatus that can reduce odor generated from a sheet.SOLUTION: An image forming apparatus 1 comprises: an image forming unit 11 that forms a toner image on a sheet P; a fixing unit 12 that thermally fixes the toner image to the sheet P; a guiding unit 31 that guides ozone generated in the image forming unit 11 to the sheet P passing through the fixing unit 12; a heating unit 32 that heats the sheet P being conveyed toward the image forming unit 11 at a temperature equal to or less than a thermal fixing temperature in the fixing unit 12; an odor detection unit 33 that detects odor generated from the sheet P heated by the heating unit 32; and an adjustment unit 35 that adjusts the flow rate of ozone that the guiding unit 31 guides to the sheet P based on a result of detection performed by the odor detection unit 33.SELECTED DRAWING: Figure 3

Description

The present invention relates to an image forming apparatus.

In an electrophotographic image forming apparatus, a means for reducing an odor generated from toner is known (Patent Document 1). In this image forming apparatus, microcapsules containing an adsorbent that adsorbs odors are sprayed on the transfer paper before fixing, and the microcapsules are destroyed by the heat or pressure during fixing to reduce the odor of the transfer paper. There is.

Japanese Unexamined Patent Publication No. 10-254313

In an electrophotographic image forming apparatus, it is considered that an odor is generated by volatilizing an odor component contained in toner and an odor component such as an aldehyde compound contained in transfer paper due to heat at the time of fixing. In the image forming apparatus described above, it is considered that the odor generated from the transfer paper can be reduced in addition to the odor generated from the toner by destroying the microcapsules to expose the adsorbed substance.

However, in the above-mentioned image forming apparatus, in addition to the cost required for producing the microcapsules containing the adsorbent, an apparatus for spraying the microcapsules on the transfer paper is required, which increases the manufacturing cost of the image forming apparatus. There was a problem of doing. In addition, since the microcapsules are consumables, the microcapsules must be replenished on a regular basis, which causes an extra running cost.

The present invention provides an image forming apparatus capable of reducing an odor generated from paper in order to solve the above-mentioned problems.

The image forming apparatus of the present invention generates an image forming portion for forming a toner image on paper, a fixing portion for thermally fixing the toner image on the paper, and an image forming portion on the paper passing through the fixing portion. Generated from the induction unit that induces ozone, the heating unit that heats the paper being conveyed toward the image forming unit at a temperature equal to or lower than the heat fixing temperature at the fixing unit, and the paper that is heated by the heating unit. It is provided with an odor detecting unit that detects the odor to be produced, and an adjusting unit that adjusts the flow rate of the ozone that the guiding unit induces on the paper based on the detection result of the odor detecting unit.

In this case, a prediction unit for predicting the odor concentration generated from the paper heat-fixed by the fixing unit based on the detection result by the odor detection unit is further provided, and the adjusting unit includes the odor predicted by the prediction unit. The flow rate of the ozone induced by the induction unit on the paper may be adjusted based on the concentration.

In this case, the guiding portion includes a pipe extending from the image forming portion to the fixing portion and a fan that sends ozone toward the fixing portion through the pipe, and the adjusting portion is a fan of the fan. The ozone flow rate may be adjusted by changing the rotation speed.

Further, in this case, the induction unit further has a valve for opening and closing the internal flow path of the pipe, and the adjusting unit performs at least one of changing the rotation speed of the fan and adjusting the opening and closing of the valve. Therefore, the flow rate of the ozone may be adjusted.

In this case, the heating unit may be built in a transport roller that transports the paper before forming the toner image.

Further, in this case, a cassette for accommodating the paper before forming the toner image is further provided, and the transport roller is a pickup roller that takes out the paper contained in the cassette and feeds it toward the image forming unit. There may be.

In this case, a second prediction unit that predicts the odor concentration generated from the toner image that is heat-fixed in the fixing unit based on the printing rate, which is the ratio of the integrated area of the toner image to the imageable area of the paper. The adjusting unit further comprises the total flow rate of the ozone flow rate based on the detection result of the odor detection unit and the ozone flow rate based on the odor concentration predicted by the second prediction unit. Based on this, the flow rate of the ozone that the induction unit induces on the paper may be adjusted.

In other cases, a second prediction that predicts the odor concentration generated from the toner image that is heat-fixed in the fixing portion based on the printing rate, which is the ratio of the integrated area of the toner image to the imageable area of the paper. The adjusting unit further comprises a unit, and the adjusting unit guides the guide unit to the paper based on the total concentration of the detection result of the odor detecting unit and the odor concentration predicted by the second predicting unit. The flow rate of the ozone may be adjusted.

According to the present invention, the odor generated from the paper can be reduced.

It is a schematic (front view) which shows the internal structure of the image forming apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the image forming apparatus which concerns on 1st Embodiment of this invention. It is the schematic (front view) which shows the deodorizing part of the image forming apparatus which concerns on 1st Embodiment of this invention. It is a flowchart which shows the action of the deodorizing part of the image forming apparatus which concerns on 1st Embodiment of this invention. It is the schematic (front view) which shows the deodorizing part of the image forming apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the image forming apparatus which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the action of the deodorizing part of the image forming apparatus which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the action of the deodorizing part of the image forming apparatus which concerns on the modification of 3rd Embodiment of this invention. It is the schematic (front view) which shows the deodorizing part of the image forming apparatus which concerns on the modification of 1st Embodiment of this invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Fr, Rr, L, R, U, and D shown in the drawings indicate front, rear, left, right, top, and bottom. Although terms indicating directions and positions are used in the present specification, these terms are used for convenience of explanation and do not limit the technical scope of the present invention.

[First Embodiment]
The image forming apparatus 1 according to the first embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic view (front view) showing the internal structure of the image forming apparatus 1. FIG. 2 is a block diagram showing an image forming apparatus 1.

[Image forming device]
The image forming apparatus 1 is a color printer that forms an image by transferring a full-color toner image formed by an electrophotographic method onto paper P. As shown in FIG. 1, the image forming apparatus 1 includes an apparatus main body 5 that constitutes a substantially rectangular parallelepiped appearance. A cassette 6 is mounted on the lower side of the apparatus main body 5 so that it can be pulled out forward. The cassette 6 contains the paper P (or a bundle of paper P) before forming the toner image. An output tray 7 for receiving the paper P on which the toner image is fixed is provided on the upper surface of the apparatus main body 5. Below the output tray 7, four toner containers 8 containing toners (developer) for replenishment of four colors (yellow, magenta, cyan, and black) are detachably mounted. Inside the apparatus main body 5, a transport path 9 serving as a path for transporting the paper P extends from the cassette 6 to the paper output tray 7. In the present specification, the "transportation direction" refers to the direction in which the paper P is conveyed.

The image forming apparatus 1 includes a paper feeding unit 10, an image forming unit 11, a fixing unit 12, a paper ejection unit 13, and a control unit 14 inside the apparatus main body 5. The paper feeding section 10 is provided at the upstream end of the transport path 9, and the paper ejection section 13 is provided at the downstream end of the transport path 9. The image-creating section 11 is provided on the downstream side in the transport direction with respect to the paper feed section 10, and the fixing section 12 is provided on the downstream side in the transport direction with respect to the image-forming section 11 and on the upstream side in the transport direction with respect to the paper ejection section 13. The control unit 14 appropriately controls the devices to be controlled such as the paper feeding unit 10, the image forming unit 11, the fixing unit 12, and the paper ejection unit 13. Further, transport rollers 15 for transporting the paper P downstream in the transport direction are provided at a plurality of locations of the transport path 9.

<Paper feed unit>
The paper feeding unit 10 has a pickup roller 10A that takes out the paper P housed in the cassette 6 and sends it out toward the image forming unit 11. The pickup roller 10A comes into contact with the uppermost surface of the stack of paper P housed in the cassette 6, rotates about an axis, separates the top-level sheet P from the stack of paper P, and sends it out to the transport path 9. .. The surface of the pickup roller 10A (the surface in contact with the paper P) is made of, for example, ethylene propylene diene rubber (EPDM) in consideration of friction with the paper P, separability of the paper P, and the like. The pickup roller 10A can also be regarded as a part of the most upstream transport roller 15 in the transport direction.

<Image drawing department>
The image forming unit 11 has a function of forming (transferring) a toner image on the paper P. The image forming unit 11 includes an intermediate transfer belt 16, four drum units 17, and an optical scanning device 18. The intermediate transfer belt 16 is provided below the toner container 8 and rotates in the direction indicated by the arrow in FIG. The four drum units 17 are arranged in the left-right direction below the intermediate transfer belt 16, and the optical scanning device 18 is provided below the drum unit 17. Since the four drum units 17 have the same structure, one drum unit 17 will be described below.

The drum unit 17 includes a photoconductor drum 20, a charging device 21, a developing device 22, a primary transfer roller 23, a cleaning device 24, and a static elimination device 25.

The photoconductor drum 20 is rotationally driven around an axis while contacting the lower surface of the intermediate transfer belt 16. The charging device 21, the developing device 22, the primary transfer roller 23, the cleaning device 24, and the static elimination device 25 are arranged around the photoconductor drum 20 in the order of the image forming process. The primary transfer roller 23 is arranged to face the photoconductor drum 20 from above with the intermediate transfer belt 16 interposed therebetween. Further, the secondary transfer roller 26 is in contact with the right end of the intermediate transfer belt 16.

<Fixing part>
The fixing unit 12 has a function of heat-fixing the toner image on the paper P. The fixing portion 12 includes a heating roller 12A that is heated by a halogen lamp, an electromagnetic induction heater, or the like, and a pressure roller 12B that forms a fixing nip between the heating roller 12A. The heating roller 12A and the pressurizing roller 12B rotate around the axis while sandwiching the paper P in the fixing nip, and pressurize the paper P (transferred toner image) while heating it.

<Paper ejection section>
The paper ejection unit 13 has an ejection roller 13A that feeds the paper P that has passed through the fixing portion 12 to the paper ejection tray 7. The discharge roller 13A rotates the paper P around an axis while sandwiching the paper P to feed the paper P to the paper discharge tray 7.

<Control unit>
As shown in FIG. 2, the control unit 14 includes an arithmetic processing unit 27, a storage unit 28, and an interface unit 29.

The arithmetic processing unit 27 is a processor that executes arithmetic processing according to a program stored in the storage unit 28. The storage unit 28 includes an auxiliary storage device such as a RAM (Random Access Memory), a ROM (Read Only Memory), and a semiconductor drive. The storage unit 28 stores (stores) programs and data used in the image forming apparatus 1. Controlled devices such as the image forming unit 11 are electrically connected to the interface unit 29. The arithmetic processing unit 27, the storage unit 28, and the interface unit 29 are electrically connected to each other. An external terminal such as a personal computer is connected to the control unit 14 (interface unit 29) via a network or the like (not shown).

[Image formation process]
Here, the operation of the image forming apparatus 1 will be described. The control unit 14 executes the image forming process as follows based on the image data input from the external terminal.

The charging device 21 charges the surface of the photoconductor drum 20 by electric discharge. The optical scanning device 18 performs exposure corresponding to the image data toward the photoconductor drum 20 and forms an electrostatic latent image on the surface of the photoconductor drum 20. The developing device 22 develops an electrostatic latent image formed on the surface of the photoconductor drum 20 into a toner image using the toner supplied from the toner container 8. The four-color toner images supported on the four photoconductor drums 20 are sequentially primary-transferred to the intermediate transfer belt 16 by the primary transfer roller 23 to which the primary transfer bias is applied. As a result, a full-color toner image is formed on the surface of the intermediate transfer belt 16.

On the other hand, the paper feeding unit 10 (pickup roller 10A) feeds the paper P in the cassette 6 to the transport path 9. The secondary transfer roller 26 to which the secondary transfer bias is applied secondarily transfers the toner image on the intermediate transfer belt 16 to the paper P passing between the intermediate transfer belt 16 and the paper P. As a result, a toner image is formed on the paper P. The fixing unit 12 heat-fixes the toner image on the paper P. The paper ejection unit 13 (emission roller 13A) ejects the paper P to the paper ejection tray 7. The cleaning device 24 removes waste toner (residual toner) remaining on the surface of the photoconductor drum 20 after the primary transfer. The static elimination device 25 irradiates the static elimination light to remove the electric charge of the photoconductor drum 20.

By the way, when the photoconductor drum 20 is charged, electrons are generated by the discharge from the charging device 21, and the oxygen in the vicinity of the charging device 21 is converted into ozone. Similarly, when a bias is applied to the primary and secondary transfer rollers 23 and 26, ozone is generated around the primary and secondary transfer rollers 23 and 26.

When the paper P on which the toner image is formed is heat-fixed, the odor component contained in the toner and the odor component such as the aldehyde compound contained in the paper P may volatilize to generate an odor. The odor may flow out from the paper ejection unit 13 to the outside of the apparatus main body 5, causing discomfort to the user. It is known that the odorous component contained in such an odor can be decomposed by the oxidizing power of ozone. Therefore, the image forming apparatus 1 according to the first embodiment includes a deodorizing unit 30 that reduces the odor generated from the toner and the paper P at the time of heat fixing by utilizing ozone generated at the time of charging or the like. Further, the deodorizing unit 30 has a function of predicting the odor generated from the paper P.

[Deodorizing part]
The deodorizing unit 30 will be described with reference to FIGS. 2 and 3. FIG. 3 is a schematic view (front view) showing the deodorizing portion 30. Note that in FIG. 3, configurations such as the toner container 8 and the optical scanning device 18 that are not necessary for explaining the deodorizing unit 30 are not shown.

As shown in FIGS. 2 and 3, the deodorizing unit 30 includes an guiding unit 31, a heating unit 32, an odor detecting unit 33, a predicting unit 34, and an adjusting unit 35. The induction unit 31 induces ozone generated by the image forming unit 11 on the paper P that has passed through the fixing unit 12. The heating unit 32 and the odor detecting unit 33 are provided on the upstream side in the transport direction with respect to the image forming unit 11. The prediction unit 34 and the adjustment unit 35 are provided as functions of the control unit 14. Although the prediction unit 34 and the adjustment unit 35 have the configuration of the control unit 14, they can also be regarded as the configuration of the deodorization unit 30.

<Induction part>
As shown in FIG. 3, the guide portion 31 has a pipe 36 and a fan 37.

(Plumbing)
The pipe 36 is a duct made of synthetic resin or metal, and extends from the image forming portion 11 to the fixing portion 12. Inside the pipe 36, an internal flow path 36A for circulating ozone from the four drum units 17 toward the fixing portion 12 is formed. In the present specification, the “distribution direction” refers to the direction in which ozone is circulated in the internal flow path 36A of the pipe 36 (see the arrow in FIG. 3).

The pipe 36 has four branch pipes 361 provided corresponding to the four drum units 17 and a merge pipe 362 that merges the four branch pipes 361 into one. A first intake port 36B corresponding to the charging device 21 and a second intake port 36C corresponding to the primary transfer roller 23 are opened on the upstream side of each branch pipe 361 in the distribution direction. An exhaust port 36D corresponding to the fixing portion 12 is opened at the downstream end of the merge pipe 362 in the distribution direction. To be precise, the exhaust port 36D is opened at a position corresponding to the downstream side in the transport direction of the fixing portion 12 (upstream side in the transport direction of the paper ejection portion 13). In the present embodiment, the charging device 21 and the primary transfer roller 23 are used as ozone supply sources, and the pipe 36 communicates the ozone supply source with the ozone supply destination downstream of the fixing portion 12 in the transport direction. There is.

(fan)
The fan 37 is an electric axial blower that rotates a propeller fan around an axis, and is fixed to an exhaust port 36D of a pipe 36 (combined pipe 362). The fan 37 has a function of sending ozone toward the fixing portion 12 through the pipe 36. Specifically, when the fan 37 is rotationally driven, ozone generated in each drum unit 17 is sucked into the pipe 36 from the first and second intake ports 36B and 36C, and flows through the internal flow path 36A. The air is exhausted from the exhaust port 36D toward the downstream side in the transport direction of the fixing portion 12.

<Heating part>
The heating unit 32 is, for example, a halogen heater and is built in the pickup roller 10A. The heating unit 32 heats the blank paper P while being conveyed by the pickup roller 10A. Specifically, the heating unit 32 heats the paper P (blank paper P) being conveyed toward the image forming unit 11 at a temperature equal to or lower than the heat fixing temperature of the fixing unit 12.

<Odor detection unit>
The odor detecting unit 33 is arranged in the vicinity of the pickup roller 10A (heating unit 32) on the downstream side in the transport direction. The odor detection unit 33 is an odor sensor that detects the odor concentration as a potential difference, such as a metal oxide semiconductor type, a crystal oscillator type, or a lipid film type. The odor detecting unit 33 detects the odor generated from the paper P heated by the heating unit 32. Since the odor generated by the heating unit 32 often goes upward, the odor detecting unit 33 may be provided above the heating unit 32 (pickup roller 10A).

As shown in FIG. 2, the fan 37, the heating unit 32, and the odor detecting unit 33 are electrically connected to the interface unit 29 of the control unit 14. The operation of the fan 37 and the heating unit 32 is controlled by the control unit 14, and the odor detection unit 33 transmits the detection result to the control unit 14.

Here, when the pickup roller 10A is heated to a high temperature, an odor derived from EPDM is generated, and the odor detecting unit 33 detects the odor generated from the pickup roller 10A (EPDM) together with the odor generated from the paper P. Therefore, the heating unit 32 heats the pickup roller 10A (blank paper P) at a temperature lower than the heat fixing temperature of the fixing unit 12 so that the odor derived from EPDM is not generated. As a specific example, the heat fixing temperature by the fixing unit 12 is about 200 degrees Celsius, and the heating temperature of the pickup roller 10A (blank paper P) by the heating unit 32 is about 100 degrees or less. Preferably, the heating temperature of the pickup roller 10A (blank paper P) by the heating unit 32 is about 70 to 80 degrees.

<Prediction section>
As shown in FIG. 2, the prediction unit 34 is realized by the arithmetic processing unit 27 and the program executed by the arithmetic processing unit 27. The prediction unit 34 predicts the odor concentration generated from the paper P heat-fixed by the fixing unit 12 based on the detection result of the odor detecting unit 33. More specifically, since the odor concentration generated when the paper P is heated increases in proportion to the heating temperature, the prediction unit 34 is a fixing unit in proportion to the odor concentration generated from the paper P heated by the heating unit 32. It is predicted that the odor concentration generated from the paper P heated in No. 12 will increase. The correspondence between the odor concentration in the heating unit 32 and the odor concentration in the fixing unit 12 was experimentally obtained in advance and stored in the storage unit 28 as a first control table (not shown). The prediction unit 34 refers to the first control table stored in the storage unit 28 based on the detection result of the odor detection unit 33, and thereby, the prediction value of the odor concentration in the fixing unit 12 (for example, the odor detection unit 33). Determines the voltage value that will be output). The detection result of the odor detecting unit 33 is a range having an upper limit and a lower limit, and a correspondence relationship between the range having the upper limit and the lower limit and the predicted value of the odor concentration is set in the first control table.

<Adjustment section>
As shown in FIG. 2, the adjusting unit 35 is realized by the arithmetic processing unit 27 and the program executed by the arithmetic processing unit 27. The adjusting unit 35 adjusts the flow rate of ozone induced by the guiding unit 31 on the paper P based on the odor concentration predicted by the predicting unit 34. Specifically, the adjusting unit 35 adjusts the ozone flow rate by changing the rotation speed of the fan 37 (for example, the rotation speed per minute). The adjusting unit 35 increases the rotation speed of the fan 37 in proportion to the predicted value of the odor concentration predicted by the predicting unit 34, and increases the supply amount of ozone to the paper P that has passed through the fixing unit 12. The correspondence between the predicted value of the odor concentration and the rotation speed of the fan 37 is experimentally obtained in advance and stored in the storage unit 28 as a second control table (not shown). The adjusting unit 35 determines the rotation speed of the fan 37 by referring to the second control table stored in the storage unit 28 based on the predicted value of the odor concentration predicted by the predicting unit 34.

[Action of deodorizing part]
Next, the action of the deodorizing unit 30 will be described with reference to FIG. FIG. 4 is a flowchart showing the action of the deodorizing unit 30.

The control unit 14 controls various controlled devices connected to the interface unit 29, and executes a deodorizing process in parallel with the image forming process already described.

In the deodorizing treatment, the control unit 14 starts energizing the heating unit 32, and the heating unit 32 heats the pickup roller 10A (S1). The pickup roller 10A sends the top-level paper P from the bundle of paper P housed in the cassette 6 to the transport path 9 while heating it (S2). The odor detection unit 33 detects the odor generated from the heated paper P while passing through the pickup roller 10A, and transmits the detection result to the control unit 14 (S3). The control unit 14 temporarily stores the received detection result in the storage unit 28. The interval (sampling rate) at which the odor detecting unit 33 detects the odor can be freely set.

The prediction unit 34 determines a predicted value of the odor concentration in the fixing unit 12 corresponding to the detection result by referring to the detection result stored in the storage unit 28 and the first control table, and stores the predicted value. It is temporarily stored in 28 (S4). The adjusting unit 35 determines the rotation speed of the fan 37 corresponding to the predicted value by referring to the predicted value stored in the storage unit 28 and the second control table, and temporarily stores the rotation speed in the storage unit 28. Remember (S5). Further, the adjusting unit 35 drives and controls the fan 37 so that the rotation speed is determined. As a result, an air flow from the first and second intake ports 36B and 36C to the exhaust port 36D is formed in the internal flow path 36A of the pipe 36.

On the other hand, the control unit 14 executes the image forming process as described above, and the paper P on which the toner image is transferred is fixed by the fixing unit 12. Ozone generated by each developing device 22 and each primary transfer roller 23 is sucked into the internal flow path 36A of the pipe 36 from the first and second intake ports 36B and 36C, passes through the internal flow path 36A, and is fixed from the exhaust port 36D. It is sprayed on the paper P that has passed through the portion 12. As a result, the odor generated from the paper P heated by the fixing portion 12 is decomposed. In addition, the odor generated from the toner melted in the fixing portion 12 is also decomposed.

As a result, the deodorizing treatment is completed, and the leakage of odor to the outside is suppressed. Further, the deodorized paper P is discharged to the paper ejection tray 7 by the paper ejection unit 13, and the image forming process is completed. When the image forming process is completed, the energization of the heating unit 32 is stopped, and the data temporarily stored in the storage unit 28 is reset (erased).

According to the image forming apparatus 1 according to the first embodiment described above, the ozone generated in the image forming unit 11 is guided to the paper P after fixing by the guiding unit 31, so that the paper P (and the paper P) are guided. The odor generated from the toner) can be reduced. Thereby, for example, the odor generated from the paper P can be reduced while suppressing the manufacturing cost and the running cost of the image forming apparatus 1 as compared with the configuration in which the adsorbent or the like is sprayed on the paper P before fixing to reduce the odor. Can be done.

Further, in the image forming apparatus 1 according to the first embodiment, the adjusting unit 35 adjusts the flow rate of ozone induced on the blank paper P according to the odor concentration. Further, the prediction unit 34 is configured to predict the odor concentration generated from the paper P at the time of heat fixing from the odor concentration generated from the blank paper P. According to this configuration, it is possible to control to increase the ozone flow rate (supply amount to the paper P) when the odor concentration is high and decrease the ozone flow rate when the odor concentration is low. As a result, it is possible to suppress the excessive supply of ozone to the periphery of the fixing portion 12 while maintaining the effect of reducing the odor, and to suppress the outflow of ozone to the outside of the image forming apparatus 1.

Further, according to the image forming apparatus 1 according to the first embodiment, the rotation speed of the fan 37 can be changed according to the odor concentration (predicted value). As a result, when the odor concentration is low, the rotation speed of the fan 37 can be reduced and wasteful energy consumption can be suppressed.

Further, according to the image forming apparatus 1 according to the first embodiment, since the heating unit 32 is built in the pickup roller 10A, the paper P can be efficiently heated while being conveyed by the pickup roller 10A.

[Second Embodiment]
Next, the image forming apparatus 2 according to the second embodiment will be described with reference to FIG. FIG. 5 is a schematic view (front view) showing the deodorizing portion 40 of the image forming apparatus 2. In the following description, the same components as those of the image forming apparatus 1 according to the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the image forming apparatus 2 according to the second embodiment, the induction unit 41 of the deodorizing unit 40 further has a valve 42 for opening and closing the internal flow path 36A of the pipe 36 in addition to the pipe 36 and the fan 37. The valve 42 is, for example, a solenoid valve and is provided on the confluence pipe 362 (on the upstream side in the distribution direction of the fan 37). The valve 42 is electrically connected to the interface unit 29 and is controlled to open and close by the control unit 14.

In the image forming apparatus 2 according to the second embodiment, the adjusting unit 35 has a function of adjusting the opening / closing of the valve 42 (changing the valve opening rate) in addition to the function of changing the rotation speed of the fan 37. Here, the opening / closing adjustment of the valve 42 means changing the valve opening rate of the valve 42. The valve opening rate of the valve 42 is the degree of opening of the valve 42, and indicates how much the internal flow path 36A of the pipe 36 is opened. For example, a valve opening rate of 100% is a state in which the valve 42 is fully opened, a valve opening rate of 50% is a state in which the internal flow path 36A is half blocked, and a valve opening rate of 0% is a state in which the internal flow path 36A is fully opened. Is completely blocked.

The adjusting unit 35 increases the valve opening rate of the valve 42 in proportion to the predicted value of the odor concentration predicted by the predicting unit 34, and increases the amount of ozone supplied to the paper P that has passed through the fixing unit 12. To be precise, the adjusting unit 35 adjusts the ozone flow rate by changing at least one of the rotation speed of the fan 37 and the opening / closing adjustment of the valve 42. Specifically, the adjusting unit 35 adjusts the ozone flow rate by adjusting the opening and closing of the valve 42 while maintaining the rotation speed of the fan 37 constant (first adjustment control). Further, the adjusting unit 35 adjusts the ozone flow rate by changing the rotation speed of the fan 37 while maintaining the valve opening rate of the valve 42 constant (second adjustment control). Further, the adjusting unit 35 adjusts the ozone flow rate by changing the rotation speed of the fan 37 and adjusting the opening and closing of the valve 42 (third adjustment control). The adjustment unit 35 executes at least one adjustment control of the first to third adjustment controls.

The correspondence between the predicted value of the odor concentration, the rotation speed of the fan 37, and the valve opening rate of the valve 42 is experimentally obtained in advance and stored in the storage unit 28 as a third control table. The adjusting unit 35 refers to the third control table stored in the storage unit 28 based on the predicted value of the odor concentration predicted by the predicting unit 34, so that the rotation speed of the fan 37 and the valve opening rate of the valve 42 can be referred to. At least one of the above is determined. The adjusting unit 35 drives and controls the fan 37 so as to have a determined rotation speed, and controls the valve 42 so as to have a determined valve opening rate.

According to the image forming apparatus 2 according to the second embodiment described above, the flow rate of ozone (the amount supplied to the paper P) can be changed according to the odor concentration, and the like is the same as the image forming apparatus 1 according to the first embodiment. The effect of can be obtained.

In the image forming apparatus 2 according to the second embodiment, one valve 42 is provided in the merge pipe 362, but the present invention is not limited to this. For example, four valves 42 may be provided in the four branch pipes 361 (not shown). In this case, the opening / closing adjustment of the valve 42 includes changing the number of valves 42 to be opened among the four valves 42 in addition to changing the valve opening rate of the valve 42.

Further, in the image forming apparatus 2 according to the second embodiment, since the fan 37 is fixed to the exhaust port 36D of the pipe 36, the valve 42 is provided on the upstream side in the distribution direction with respect to the fan 37. Not limited to this. When the fan 37 is fixed on the upstream side in the distribution direction with respect to the exhaust port 36D, the valve 42 may be provided on the downstream side in the distribution direction with respect to the fan 37 (not shown).

[Third Embodiment]
Next, the image forming apparatus 3 according to the third embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a block diagram showing an image forming apparatus 3. FIG. 7 is a flowchart showing the operation of the deodorizing unit 50 of the image forming apparatus 3. In the following description, the same components as those of the image forming apparatus 1 according to the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 6, in the image forming apparatus 3 according to the third embodiment, the deodorizing unit 50 further includes a second predicting unit 38. The second prediction unit 38 is realized by the arithmetic processing unit 27 and the program executed by the arithmetic processing unit 27, similarly to the prediction unit 34. The second prediction unit 38 predicts the odor concentration generated from the toner image heat-fixed by the fixing unit 12 based on the printing rate. The print ratio is the ratio of the integrated area of the toner image to the imageable area (area where the toner image can be formed) of the paper P. The print rate is calculated from the image data input to the control unit 14. Since the odor concentration generated from the toner image (toner) during heat fixing increases in proportion to the amount of toner, the second prediction unit 38 determines the odor generated from the toner image during heat fixing in proportion to the increase in the printing rate. Predict that the concentration will increase. The correspondence between the print rate and the odor concentration in the fixing unit 12 was experimentally obtained in advance and stored in the storage unit 28 as a fourth control table (not shown). The second prediction unit 38 refers to the fourth control table stored in the storage unit 28 based on the printing rate, so that the predicted value of the odor concentration in the fixing unit 12 (for example, the odor detection unit 33 outputs). Determine the voltage value that will be applied).

In the image forming apparatus 3 according to the third embodiment, the adjusting unit 35 determines the ozone flow rate based on the odor concentration predicted by the prediction unit 34 and the ozone flow rate based on the odor concentration predicted by the second prediction unit 38. And decide. The correspondence between the predicted value of the odor concentration predicted by the prediction unit 34 and the ozone flow rate is experimentally obtained in advance and stored in the storage unit 28 as a fifth control table (not shown). The correspondence between the predicted value of the odor concentration predicted by the second prediction unit 38 and the ozone flow rate was experimentally obtained in advance and stored in the storage unit 28 as a sixth control table (not shown). There is. The adjusting unit 35 determines the flow rates of the two ozones by referring to the fifth and sixth control tables.

Further, the adjusting unit 35 is based on the total flow rate of the ozone flow rate based on the odor concentration predicted by the prediction unit 34 and the ozone flow rate based on the odor concentration predicted by the second prediction unit 38. The induction unit 31 adjusts the flow rate of ozone induced on the paper P. The adjusting unit 35 increases the rotation speed of the fan 37 in proportion to the total flow rate, and increases the amount of ozone supplied to the paper P that has passed through the fixing unit 12. The correspondence between the total flow rate and the rotation speed of the fan 37 has been experimentally obtained in advance and stored in the storage unit 28 as a seventh control table (not shown). The adjusting unit 35 determines the rotation speed of the fan 37 by referring to the seventh control table based on the total flow rate.

[Action of deodorizing part]
As shown in FIG. 7, in the deodorizing process, the control unit 14 calculates the print rate from the image data input from the external terminal and stores it in the storage unit 28 (S10). The second prediction unit 38 determines the predicted value of the odor concentration in the fixing unit 12 corresponding to the print rate by referring to the print rate stored in the storage unit 28 and the fourth control table, and the predicted value. Is temporarily stored in the storage unit 28 (S11).

Further, the control unit 14 controls various control target devices in the same manner as the deodorization process in the image forming apparatus 1 according to the first embodiment. That is, the heating unit 32 heats the pickup roller 10A (S1), the pickup roller 10A heats the paper P and sends it out to the transport path 9 (S2), and the odor detection unit 33 detects the odor generated from the paper P to be transported. Detect (S3). The prediction unit 34 determines a predicted value of the odor concentration generated from the paper P in the fixing unit 12, and temporarily stores the predicted value in the storage unit 28 (S4).

The adjusting unit 35 calculates the ozone flow rate based on the odor concentration derived from the paper P with reference to the fifth control table, and calculates the ozone flow rate based on the odor concentration derived from the toner with reference to the sixth control table. Then, the total flow rate obtained by adding them is calculated and temporarily stored in the storage unit 28 (S12). The adjusting unit 35 determines the rotation speed of the corresponding fan 37 with reference to the total flow rate and the seventh control table, and temporarily stores the rotation speed in the storage unit 28 (S13). Further, the adjusting unit 35 drives and controls the fan 37 so that the rotation speed is determined.

As a result, ozone is sprayed onto the paper P that has passed through the fixing portion 12, and the odor generated from the toner melted in the fixing portion 12 and the odor generated from the heated paper P are decomposed.

According to the image forming apparatus 3 according to the third embodiment described above, the ozone flow rate can be changed according to the total flow rate based on the odor concentration generated from the toner (toner image) and the paper P. As a result, it is possible to suppress the excessive supply of ozone to the periphery of the fixing portion 12 while maintaining the effect of reducing the odor, and to suppress the outflow of ozone to the outside of the image forming apparatus 3.

In the image forming apparatus 3 according to the third embodiment, the adjusting unit 35 calculates the total flow rate, but the total flow rate is not limited to this, and either the prediction unit 34 or the second prediction unit 38 calculates the total flow rate. It may be calculated.

[Modified example of the third embodiment]
In the image forming apparatus 3 according to the third embodiment, the adjustment unit 35 actually induces the ozone flow rate to the paper P based on the total flow rate of the ozone flow rate derived from the paper P and the ozone flow rate derived from the toner. However, the present invention is not limited to this.

As the image forming apparatus 3 according to the modified example of the third embodiment, the adjusting unit 35 calculates the total concentration obtained by adding the odor concentrations (two predicted values) predicted by the prediction unit 34 and the second prediction unit 38. You may. The adjusting unit 35 adjusts the flow rate of ozone induced by the guiding unit 31 on the paper P based on the total concentration. The adjusting unit 35 increases the rotation speed of the fan 37 in proportion to the calculated total concentration (predicted value), and increases the amount of ozone supplied to the paper P that has passed through the fixing unit 12. The correspondence between the total concentration and the rotation speed of the fan 37 has been experimentally obtained in advance and stored in the storage unit 28 as an eighth control table (not shown). The adjusting unit 35 determines the rotation speed of the fan 37 by referring to the eighth control table stored in the storage unit 28 based on the total concentration.

As shown in FIG. 8, in the deodorizing process, the adjusting unit 35 calculates the total concentration by adding the predicted value of the odor concentration derived from the toner and the predicted value of the odor concentration derived from the paper P, and stores the predicted value. It is temporarily stored in 28 (S14). The adjusting unit 35 determines the rotation speed of the corresponding fan 37 with reference to the predicted value of the total concentration stored in the storage unit 28 and the eighth control table, and temporarily stores the rotation speed in the storage unit 28. Remember (S15). Further, the adjusting unit 35 drives and controls the fan 37 so that the rotation speed is determined.

According to the image forming apparatus 3 according to the modification of the third embodiment described above, the ozone flow rate can be changed based on the total concentration generated from the toner (toner image) and the paper P. As a result, it is possible to suppress the excessive supply of ozone to the periphery of the fixing portion 12 while maintaining the effect of reducing the odor, and to suppress the outflow of ozone to the outside of the image forming apparatus 3.

In the image forming apparatus 3 according to the modified example of the third embodiment, the adjusting unit 35 calculates the total density, but the present invention is not limited to this, and either the prediction unit 34 or the second prediction unit 38 can be used. The total concentration may be calculated.

In the image forming apparatus 3 according to the third embodiment (including a modification, the same applies hereinafter), the second prediction unit 38 has a different configuration from the prediction unit 34, but the prediction unit 34 has a second configuration. The function may be included as the prediction unit 38 of the above.

Further, the features of the image forming apparatus 3 according to the third embodiment (such as predicting the odor concentration from the printing rate) may be applied to the image forming apparatus 2 according to the second embodiment.

In the image forming devices 1 to 3 according to the first to third embodiments, in order to use the charging device 21 and the primary transfer roller 23 as ozone supply sources, the first intake port is connected to each branch pipe 361 of the pipe 36. The 36B and the second intake port 36C are open, but the present invention is not limited to this. For example, only one of the charging device 21 and the primary transfer roller 23 may be used as the ozone supply source, and only one of the first intake port 36B and the second intake port 36C may be open to the branch pipe 361 (. Not shown). Further, as shown in FIG. 9, in addition to the charging device 21 and the primary transfer roller 23, a branch tube 361 corresponding to the secondary transfer roller 26 is further provided in order to use the secondary transfer roller 26 as a supply source of ozone. The third intake port 36E may be opened in the branch pipe 361 (a modification of the first embodiment). In FIG. 9, the third intake port 36E is applied to the image forming apparatus 1 according to the first embodiment, but it may be applied to the image forming apparatus 2 and 3 according to the second and third embodiments. The branch pipe 361 may be provided so that at least one of the charging device 21, the primary transfer roller 23, and the secondary transfer roller 26 is provided as a supply source of ozone, and the first intake port 36B, the first At least one of the two intake ports 36C and the third intake port 36E may be open to the branch pipe 361 (not shown).

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments (including each modification; the same applies hereinafter), the heating unit 32 heats the pickup roller 10A (blank paper P) from the heat fixing temperature. Was heated at a low temperature, but the present invention is not limited to this. The heating unit 32 may heat the conveyed blank paper P at a temperature equal to or lower than the heat fixing temperature. For example, the blank paper P may be heated at the same temperature as the heat fixing temperature. For example, when the pickup roller 10A is made of a material that does not easily generate an odor at a high temperature, or when the heating time of the pickup roller 10A by the heating unit 32 is very short, the paper P is heated at the heat fixing temperature. May be good.

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments, the deodorizing units 30, 40, and 50 have the prediction unit 34, but the present invention is not limited to this, and the prediction unit 34 is omitted. May be good. For example, in the image forming apparatus 1 and 2 according to the first and second embodiments, the adjusting unit 35 determines the flow rate of ozone induced by the guiding units 31 and 41 on the paper P based only on the detection result of the odor detecting unit 33. You may adjust. Further, for example, in the image forming apparatus 3 according to the third embodiment, the adjusting unit 35 determines the ozone flow rate based on the detection result of the odor detecting unit 33 and the ozone based on the odor concentration predicted by the second predicting unit 38. The ozone flow rate is adjusted based on the total flow rate of the above and the total flow rate. Further, for example, in the image forming apparatus 3 according to the modified example of the third embodiment, the adjusting unit 35 adds up the detection result of the odor detecting unit 33 and the odor concentration predicted by the second predicting unit 38. Adjust the ozone flow based on the total concentration. The configuration in which the prediction unit 34 is omitted is effective when the heating unit 32 heats the paper P at the same temperature as the heat fixing temperature.

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments, the fan 37 is an axial blower, but the fan 37 is not limited to this, and a centrifugal blower such as a sirocco fan may be used. Further, the fan 37 is fixed to the downstream end (exhaust port 36D) of the pipe 36 in the distribution direction, but the present invention is not limited to this. For example, the fan 37 may be fixed to the upstream end of the pipe 36 in the distribution direction, specifically, at least one of the first intake port 36B and the second intake port 36C (not shown). In addition, the fan 37 may be provided in the middle of the pipe 36 (not shown). That is, the fan 37 may be provided at any position of the pipe 36, and it is sufficient that an air flow from the image forming portion 11 to the fixing portion 12 can be created in the internal flow path 36A.

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments, the heating unit 32 is a halogen heater, but the present invention is not limited to this, and for example, an electric resistor mounted on a substrate may be used. It may be an electromagnetic induction type heater (neither is shown).

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments, the heating unit 32 is built in the pickup roller 10A, but the present invention is not limited to this. The heating unit 32 may be built in any one of a plurality of transfer rollers 15 arranged between the pickup roller 10A and the secondary transfer roller 26. That is, the heating unit 32 may be built in the transport roller 15 that conveys the paper P before forming (transferring) the toner image. Further, the heating unit 32 does not have to be built in the pickup roller 10A or the like, and may be provided adjacent to the transfer path 9 on the upstream side in the transfer direction from the secondary transfer roller 26. That is, the heating unit 32 may directly heat the paper P instead of heating the paper P via the pickup roller 10A.

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments, the prediction unit 34 predicts the odor concentration in the fixing unit 12 with reference to the first control table. Not limited to this. For example, the control unit 14 (calculation processing unit 27) may execute a proportional calculation from the detection result of the odor detection unit 33 to calculate the odor concentration in the fixing unit 12. Similarly, in the image forming apparatus 3 according to the third embodiment, the second prediction unit 38 predicts the odor concentration with reference to the fourth control table, but the present invention is not limited to this, for example. The odor concentration in the fixing unit 12 may be calculated by executing a proportional calculation from the print rate.

Further, in the image forming apparatus 1 to 3 according to the first to third embodiments, the deodorizing units 30, 40, and 50 are controlled by the control unit 14 provided in the image forming apparatus 1, but the control unit 14 deodorizes. It may be regarded as the composition of parts 30, 40, and 50. Further, apart from the control unit 14, a dedicated control unit for controlling the deodorizing units 30, 40, 50 may be provided (not shown).

Further, in the description of the first to third embodiments, the case where the present invention is applied to a color printer is shown as an example, but the present invention is not limited to this, and the present invention is not limited to this, for example, to a monochrome printer, a copying machine, a facsimile, a multifunction device, or the like. The invention may be applied.

The description of the embodiment shows one aspect of the image forming apparatus according to the present invention, and the technical scope of the present invention is not limited to the above embodiment. The present invention may be variously modified, replaced or modified without departing from the spirit of the technical idea, and the claims include all embodiments that may be included within the scope of the technical idea.

1,2,3 Image forming device 6 Cassette 10A Pickup roller 11 Image forming part 12 Fixing part 15 Conveying roller 31,41 Induction part 32 Heating part 33 Odor detection part 34 Prediction part 35 Adjustment part 36 Piping 37 Fan 38 Second prediction Part 42 Valve P Paper

Claims (8)

An image forming part that forms a toner image on paper,
A fixing portion for heat-fixing the toner image on the paper, and a fixing portion.
An induction unit that induces ozone generated in the image formation unit on the paper that has passed through the fixing unit,
A heating unit that heats the paper being conveyed toward the image forming unit at a temperature equal to or lower than the heat fixing temperature at the fixing unit.
An odor detecting unit that detects an odor generated from the paper heated by the heating unit, and an odor detecting unit.
An image forming apparatus comprising: an adjusting unit for adjusting the flow rate of ozone guided by the guiding unit to the paper based on the detection result of the odor detecting unit. Further provided is a prediction unit for predicting the odor concentration generated from the paper that is heat-fixed in the fixing unit based on the detection result of the odor detection unit.
The image forming apparatus according to claim 1, wherein the adjusting unit adjusts the flow rate of ozone induced by the guiding unit on the paper based on the odor concentration predicted by the predicting unit. The guide portion
The piping extending from the image forming part to the fixing part,
It has a fan that sends the ozone toward the fixing portion through the pipe.
The image forming apparatus according to claim 1 or 2, wherein the adjusting unit adjusts the flow rate of ozone by changing the rotation speed of the fan. The guide portion further has a valve that opens and closes the internal flow path of the pipe.
The image forming apparatus according to claim 3, wherein the adjusting unit adjusts the flow rate of ozone by changing at least one of the rotation speed of the fan and the opening / closing adjustment of the valve. The image forming apparatus according to any one of claims 1 to 4, wherein the heating unit is built in a conveying roller that conveys the paper before forming the toner image. A cassette for accommodating the paper before forming the toner image is further provided.
The image forming apparatus according to claim 5, wherein the transport roller is a pickup roller that takes out the paper contained in the cassette and sends it out toward the image forming unit. Further provided with a second prediction unit that predicts the odor concentration generated from the toner image that is heat-fixed by the fixing unit based on the printing rate, which is the ratio of the integrated area of the toner image to the imageable area of the paper. ,
The adjusting unit induces the ozone flow rate based on the total flow rate of the ozone flow rate based on the detection result of the odor detecting unit and the ozone flow rate based on the odor concentration predicted by the second prediction unit. The image forming apparatus according to any one of claims 1 to 6, wherein the unit adjusts the flow rate of the ozone guided to the paper. Further provided with a second prediction unit that predicts the odor concentration generated from the toner image that is heat-fixed by the fixing unit based on the printing rate, which is the ratio of the integrated area of the toner image to the imageable area of the paper. ,
The adjusting unit determines the flow rate of ozone that the guiding unit induces on the paper based on the total concentration of the detection result of the odor detecting unit and the odor concentration predicted by the second predicting unit. The image forming apparatus according to any one of claims 1 to 6, wherein the image forming apparatus is adjusted.

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