JP2003005576A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve image quality, to prevent damage of a heater unit, to prevent paper jamming and to improve loading function of sheet material by carrying out setting of fixing temperature, transfer voltage and curling correction appropriately for the paper to be used for a device to be changed manually depending on the type and the size of the paper. SOLUTION: In the apparatus, a paper type and size changeover device is provided in front of a cassette and the changeover device is set by the user according to the paper that is used. For example, when set to print on small size thick paper (such as a post card), a heating body for small size which is on the short side is set to be heated to 205 deg.C which is higher temperature than usual.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine,
The present invention relates to an image forming apparatus using an electrophotographic system such as a laser beam printer or a facsimile, or an electrostatic recording system.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a laser beam printer, a developing device for developing a latent image drawn by laser light or the like, a transfer means for transferring the developed toner image to a recording material, and a transfer device The mainstream is a device provided with a fixing device (fixing device) for fixing the formed toner image on a recording material.

FIG. 14 shows a conventional laser beam printer as a typical example.

FIG. 15 is a sectional view of the conventional laser beam printer shown in FIG.

FIG. 16 is an enlarged view of the control panel shown in FIG.

The overall structure and function of this laser beam printer will be described below.

A paper feed cassette 2 is mounted below the image forming apparatus main body 1, and a recording material P is placed on a sheet stacking plate 201.
Is loaded. The recording material P is fed by a pickup roller 202 driven by a main motor (not shown) to rotate the recording material P.
And pair of paper feed rollers 2 composed of retard roller 203b
03, and after separating the recording materials P one by one,
It consists of a first transport roller 301a and a roller 301b,
The sheet is fed to the first pair of transport rollers 301. The recording material P transported to the first transport roller pair 301 is transported to the second transport roller pair 302 including the second transport roller 301a and the roller 302b, and further, the transfer photoconductor 401 and the transfer roller 402. Is transferred to the transfer section. In the transfer section, an image signal processed by a controller (not shown) is written by the scanner 5 as an electrostatic latent image on the transfer photoconductor 401, and the electrostatic latent image is developed by the toner T. At this time, the toner T is negatively charged and the recording material P is positively charged by the transfer roller 402. Therefore, when the potential of the recording material P is higher than that of the toner T, the electrostatic latent image developed with the toner T is developed. The image is attracted to the recording material P and transferred as an unfixed image.

The recording material P to which the unfixed image is transferred is conveyed to the fixing device 6. The recording material P is the heater unit 601.
Then, the unfixed image on the recording material P that has been conveyed is fixed by being heated and pressed at a predetermined pressure by the pressure roller 602.

The heater unit 60T has a plurality of heating elements, and the heating element to be energized is switched according to the data of the recording material input from the control panel. When using a recording material having a width of 114 mm (DL envelope) or less, a heating element for a small size is used.

The recording material P on which the unfixed image is fixed can be switched between the conveyance paths by the flapper 605. When the user has opened the face-up tray 703, the recording material P is switched to be discharged toward the face-up tray 703, and the user can open the face-up tray 70.
When 3 is closed, the recording material P is switched to the face-down tray 702. In FIG. 15, the recording material P is set to be discharged toward the face-down tray 702.

The recording material P whose conveyance path has been switched by the flapper is conveyed to a second paper ejection roller pair 701 which is composed of a second paper ejection roller 701a and a roller 701b which are recording material curving correction means. Since the recording material P is curved in the process of passing through the curved conveyance path, it is sandwiched by the second paper discharge roller pair 701 from above and below with a constant pressure in the recording material curving correction means, and as a result, the recording material P is curved in a flat plane. The shape of the face-down tray 70
The paper is discharged and stacked in No. 2.

Generally, the recording material P has various weights (thicknesses), types (OHTs, etc.), and surface properties (label paper, coated paper).
There is a fixing process. In the conventional technology, some optimum modes according to the type of sheet material are stored in the image forming apparatus main body 1 in advance, and the user uses the control panel shown in FIG. I was setting the lead.

Further, the recording material curving correction means works with a constant pressure on any kind of recording material, and the recording material discharge port is switched by the user for each type of recording material by referring to the instruction manual. I was using it.

[0014]

However, in the above-mentioned conventional example, since the optimum mode of the transfer process or the fixing process is set according to the characteristics of the sheet material used by the user, if the user's setting is inappropriate, There is a drawback that the image quality is deteriorated due to the improper transfer fixing process.

For example, when a special paper having a high electric resistance value (specified in the instruction manual) is printed improperly, if such a paper is improperly set, such a paper is hard to be charged, and therefore the potential is set to a normal voltage. The toner cannot be taken sufficiently high, and the negatively charged toner is difficult to be transferred to the surface of the recording material, and a part of the toner is not transferred to the recording material, so that the image may be missing.

For example, if the paper is set improperly when printing thick paper, the fixing temperature is low with respect to the recording material to be used, and the toner is not fixed on the recording material because heat such as moisture is not generated.

Further, when printing a small-sized recording material, if the setting of the printing paper size is inappropriate, a short-sized heater for small size (601c in FIG. 2) is used instead of a heater for normal size (601 in FIG. 2, heat generation). However, there is a drawback that the end of the fixing device where the recording material does not pass is heated and the heater unit is damaged.

Further, when a user replaces a cassette loaded with different sheet materials, printing is performed without changing the setting of the recording material, which causes the above-mentioned deterioration of image quality, and there is also a drawback. When sorting and stacking various types of sheet materials such as cassettes, there is also a drawback that the setting must be changed for each sheet material to be printed.

Further, if the setting of the sheet material discharge port after image formation is improper, the sheet material may be clogged inside the image forming apparatus, the sheet material may be broken or scratched, and the sheet material may be curled. There was also.

Further, since the setting of the curl correction means is constant regardless of the characteristics of the sheet material, curl correction is not often performed when printing thick paper, for example, and the recording material is ejected while curled, and conversely for thin paper. Curling correction is too strong and curls in the opposite direction and is ejected. As a result, ejected sheet materials are pushed out of the tray one after another, the number of sheets that can be stacked on the tray is reduced, and handling of sheet material after printing There was also a drawback that it became difficult.

[0021]

The present invention is an image forming apparatus having the following configuration.

(1) According to the first aspect of the invention, a recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an unfixed image on the recording material. In an image forming apparatus having an image forming unit for forming, a fixing unit for fixing an unfixed image on a recording material, and a plurality of heating elements in the fixing unit, at least the type of recording material is set in the recording material stacking unit. A recording material type switching unit for manually switching is provided, and energization to the plurality of heating elements is switched according to the setting of the recording material type switching unit.

(2) According to the second aspect of the invention, a recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an unfixed image on the recording material. In an image forming apparatus having an image forming means for forming, a fixing means for fixing an unfixed image on a recording material, and a plurality of heating elements in the fixing means, at least the kind of the recording material is set in the recording material supplying means. It is characterized in that a recording material type switching means for manually switching is installed, and energization to the plurality of heating elements is switched according to the setting of the recording material type switching means.

(3) According to a third aspect of the invention, recording material stacking means for stacking a plurality of recording materials, recording material supply means for supplying the recording materials to the image forming means, and an unfixed image on the recording material. In an image forming apparatus having an image forming means for forming and a fixing means for fixing an unfixed image on a recording material, the recording material stacking means has at least a recording material type switching means for manually switching the type of recording material. However, the heating element is controlled to an optimum temperature for the recording material according to the setting of the recording material type switching unit.

(4) The invention according to claim 4 is a recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an unfixed image on the recording material. In an image forming apparatus having an image forming means for forming and a fixing means for fixing an unfixed image on a recording material, the recording material supplying means has at least a recording material type switching means for manually switching the recording material type. However, the heating element is controlled to an optimum temperature for the recording material according to the setting of the recording material type switching unit.

(5) According to the invention of claim 5, a recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an unfixed image on the recording material. In an image forming apparatus having an image forming means for forming and a fixing means for fixing an unfixed image on a recording material, the recording material stacking means has at least a recording material type switching means for manually switching the type of recording material. Then, in accordance with the setting of the recording material type switching means, when transferring the image on the photosensitive drum in the image forming means to the recording material, the transfer voltage for charging the recording material is set to an optimum value for the recording material. It is characterized by controlling.

(6) According to a sixth aspect of the invention, recording material stacking means for stacking a plurality of recording materials, recording material supplying means for supplying the recording materials to the image forming means, and unfixed images on the recording materials. In an image forming apparatus having an image forming means for forming and a fixing means for fixing an unfixed image on a recording material, the recording material supplying means has at least a recording material type switching means for manually switching the recording material type. Then, in accordance with the setting of the recording material type switching means, when transferring the image on the photosensitive drum in the image forming means to the recording material, the transfer voltage for charging the recording material is set to an optimum value for the recording material. It is characterized by controlling.

(7) According to a seventh aspect of the invention, recording material stacking means for stacking a plurality of recording materials, recording material supply means for supplying the recording materials to the image forming means, and unfixed images on the recording materials. An image forming unit for forming, a fixing unit for fixing an unfixed image on a recording material, a first discharging and stacking unit for discharging and stacking the recording material on the front side, and a second discharging and stacking unit for discharging and stacking the recording material on the back side. In an image forming apparatus having an ejecting and stacking means, and an ejecting switching means for switching the conveyance of the recording material to the first ejecting and stacking means and the second ejecting and stacking means, at least the kind of the recording material is set in the recording material stacking means. A recording material type switching means for manually switching, switching the discharge switching means in response to a signal from the recording material type switching means,
The present invention is characterized in that the discharge and stacking means suitable for the recording material is controlled to change the conveyance of the recording material.

(8) According to the invention described in claim 8, a recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an unfixed image on the recording material. An image forming unit for forming, a fixing unit for fixing an unfixed image on a recording material, a first discharging and stacking unit for discharging and stacking the recording material on the front side, and a second discharging and stacking unit for discharging and stacking the recording material on the back side. In an image forming apparatus having an ejecting and stacking means and an ejecting switching means for switching the conveyance of the recording material to the first ejecting and stacking means and the second ejecting and stacking means, at least the kind of the recording material is added to the recording material supply means. A recording material type switching means for manually switching, switching the discharge switching means in response to a signal from the recording material type switching means,
The present invention is characterized in that the discharge and stacking means suitable for the recording material is controlled to change the conveyance of the recording material.

(9) According to a ninth aspect of the invention, recording material stacking means for stacking a plurality of recording materials, recording material supplying means for supplying the recording materials to the image forming means, and unfixed images on the recording materials. An image forming apparatus comprising: an image forming unit that forms an image; a fixing unit that fixes an unfixed image on a recording material; and a curl correcting unit that corrects a curl of the recording material generated by the fixing unit. , At least having a recording material type switching means for manually switching the recording material type,
It is characterized in that control for changing the setting of the curl correcting means is performed according to a signal from the recording material type switching means.

(10) According to a tenth aspect of the invention, recording material stacking means for stacking a plurality of recording materials, recording material supplying means for supplying the recording materials to the image forming means, and an unfixed image on the recording materials. An image forming apparatus comprising: an image forming unit that forms an image; a fixing unit that fixes an unfixed image on a recording material; and a curl correcting unit that corrects a curl of the recording material caused by the fixing unit. , At least a recording material type switching means for manually switching the recording material type, in accordance with a signal from the recording material type switching means,
It is characterized in that control for changing the setting of the curl correcting means is performed. <Operation> a) Since the optimum mode of the transfer process and the fixing process is automatically determined by the user manually switching the switch depending on the type of the sheet material, the improper transfer / fixing process due to the setting mistake of the recording material is performed. As a result, part of the toner is not transferred to the recording material and the image may be missing, or the toner may not be fixed on the recording material due to insufficient heat transfer to the recording material. In addition, images can be formed on a wide variety of sheet materials.

B) Since the user manually switches the switch depending on the type of sheet material to automatically change the heater to be used, it is possible to prevent the heater unit from being damaged due to the temperature rise at the end of the fixing device. .

C) By mounting the switch on the sheet material stacking device, it is possible to save the trouble of changing the setting of the sheet material each time the sheet material stacking device is replaced, and to optimize the transfer process and fixing process for each sheet material stacking device. Image formation is possible.

D) By mounting the switching device on the sheet feeding device for feeding the sheet material, even when sorting and stacking various kinds of sheet materials, the optimum transfer process and fixing process for each sheet feeding device are performed. Image formation is possible.

E) Since the user manually switches the switch depending on the type of the sheet material to automatically switch the sheet material discharge port, a sheet material jam or a sheet material jam in the image forming apparatus due to a non-optimal discharge port selection It is possible to prevent folds, scratches and curling of the sheet material.

F) The curl straightening setting is changed for each recording material by the user manually switching the switch depending on the type of the sheet material. Therefore, the optimum curl straightening setting can be set for any recording material. Therefore, the stackability of the sheet material is improved, and the sheet material after printing is easily handled.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION The image forming apparatus and the switching apparatus according to the present invention will be described below in more detail with reference to the drawings. In the embodiments described below, the present invention is embodied in the image forming apparatus shown in FIG. Therefore,
A detailed description of the entire image forming apparatus and its functions will be omitted, and only the features of the present invention will be described. Further, the same reference numerals are given to members having the same functions as the above-mentioned members,
The description is omitted.

(First Embodiment) A first embodiment of the image forming apparatus of the present invention will be described with reference to FIGS.

FIG. 1 shows how a user prints a small size cardboard.

FIG. 2 shows a ceramic heater of the fixing device.

FIG. 3 shows an image forming process which is switched by the paper type switching device.

As shown in FIG. 1, this image forming apparatus (laser beam printer in the embodiment) has a recording material stacking device (hereinafter referred to as a cassette) with a paper type switching device A. Is set by the user, the optimum transfer process and fixing process are automatically set as shown in FIG. 3 (Example 1 in the drawing).

The recording material P to which the unfixed image is transferred is conveyed to the fixing device 6. The recording material P is the heater unit 601.
Then, the unfixed image on the recording material P that has been conveyed is fixed by being heated and pressed at a predetermined pressure by the pressure roller 602. Heater unit 60 that constitutes the fixing device 6
As shown in FIG. 2, the ceramic heater 601a inside one is composed of two types of heaters 601b and 601c, long and short, and the heater to be used is switched depending on the size of the paper. When the user sets the paper type switching device for small size paper (card, envelope, etc.) as shown in FIG. 1, the ceramic heater 601a of FIG. 2 is set so that the small size heater 601c generates heat. As a result, the fixing device (the portion through which the sheet material does not pass) does not generate heat, and it is possible to prevent the heater unit from being damaged due to an abnormal temperature rise.

Further, since the heat transfer to thick paper is poor and the toner fixability is not good, the temperature of the heater is set higher than usual (205 ° C.) and the image is reliably fixed to the sheet material (FIG. 3). ).

Each set value shown in FIG. 3 is recorded in the main body in advance, and is automatically set by the user switching the paper type switching device.

With the above configuration, the user switches the switch depending on the type of the sheet material to automatically determine the optimum mode of the transfer process and the fixing process. It is possible to prevent the image quality from being deteriorated and to form an image on various sheet materials.

Further, since the heater to be used is automatically changed, it is possible to prevent the heater unit from being damaged due to the temperature rise at the end of the fixing device during printing of small size paper.

Further, by mounting the switching means on the cassette loaded with the sheet material, it is possible to save the trouble of changing the setting of the sheet material each time the cassette is replaced, and the image in the optimum transfer process and fixing process for each cassette can be saved. Can be formed.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS.

FIG. 2 shows a ceramic heater of the fixing device.

FIG. 3 shows an image forming process which is switched by the paper type switching device.

FIG. 4 shows how the user prints a normal size OHT.

As shown in FIG. 4, this image forming apparatus (laser beam printer in the embodiment) has a paper type switching device A on the front surface of the cassette, and the user can set the switching device. 3 (Example 2 in the figure), the optimum transfer process and fixing process are automatically set.

The recording material P to which the unfixed image is transferred is conveyed to the fixing device 6. The recording material P is the heater unit 601.
Then, the pressure roller 602 heats and pressurizes the recording material P at a predetermined pressure to fix the unfixed image on the recording material P that has been conveyed. Heater unit 6 that constitutes the fixing device 6
As shown in FIG. 2, the ceramic heater 601a inside 01 is composed of long and short type heaters 601b and 601c, and the heater to be used is switched according to the size of the paper. By setting the paper type switching device to the OHT of the normal size as shown in Fig. 4,
The ceramic heater 601a is a normal size heater 60.
Since 1b generates heat and OHT is weak to heat, the temperature of the heater is set lower than usual, about 180 ° C.

The set values shown in FIG. 3 are recorded in advance in the main body, and are automatically set by the user switching the paper type switching device.

With the above configuration, the user switches the switch depending on the type of the sheet material to automatically determine the optimum mode of the transfer process and the fixing process. It is possible to prevent the image quality from being deteriorated and to form an image on various sheet materials.

Further, by mounting the switching button on the cassette loaded with the sheet material, it is possible to save the trouble of changing the setting of the sheet material each time the cassette is replaced, and to perform the optimum transfer process and fixing process for each cassette. It becomes possible to form an image.

(Third Embodiment) A third embodiment of the image forming apparatus of the present invention will be described with reference to FIGS.

FIG. 3 shows an image forming process which is switched by the paper type switching device. FIG. 5 shows a state in which different recording materials are stacked on the two-stage recording material supply means and special paper (high resistance paper) is printed by the upper supply means. FIG. 6 shows the transfer process.

As shown in FIG. 5, this image forming apparatus (laser beam printer in the embodiment) has a paper type switching device A on the front surface of the recording material supplying means, and the switching device is set by the user. As a result, the optimum transfer process and fixing process are automatically set as shown in FIG. 3 (the upper part of the third embodiment in the drawing).

As shown in FIG. 6, in the transfer section composed of the transfer photoconductor 401 and the transfer roller 402, the image signal processed by the controller (not shown) is electrostatically transferred to the transfer photoconductor 401 by the scanner 5. It is written as a latent image, and the electrostatic latent image is developed with toner T. At this time, the toner T is negatively charged and the recording material P is positively charged by the transfer roller 402. Therefore, when the potential of the recording material P is higher than that of the toner T, the electrostatic latent image developed with the toner T is developed. The image is attracted to the recording material P and transferred as an unfixed image.

FIG. 5 shows a state in which the user has set the upper feeding means to special paper of normal size. Special paper with high electric resistance value (specified in the instruction manual) is difficult to be charged, so
When the user switches the paper type switching device, a voltage higher than usual is applied to the transfer roller 402, and a current of about 8 μA flows between the transfer roller 402, the recording material P, and the transfer photoconductor 401. . As a result, the potential of the recording material P becomes sufficiently higher than the potential of the toner T, so that the electrostatic latent image is attracted to the recording material P and transferred as an unfixed image.

Each set value shown in FIG. 3 is recorded in the main body in advance, and is automatically set by the user switching the paper type switching device.

Further, in the case of feeding / printing, for example, A4 size plain paper from the lower supply means set to the normal size plain paper, the transfer / fixing is performed as shown in FIG. 3 (the lower part of the third embodiment in the drawing). The process switches automatically.

With the above structure, the user can switch the switch depending on the type of the sheet material to automatically determine the optimum mode of the transfer process and the fixing process. It is possible to prevent the image quality from being deteriorated and to form an image on various sheet materials.

Further, by mounting the switching button on the recording material supply means, even when various kinds of sheet materials such as a multi-stage cassette are sorted and stacked, the optimum transfer process and fixing for each recording material supply means are performed. Image formation in the process becomes possible.

(Fourth Embodiment) A fourth embodiment of the image forming apparatus of the present invention will be described with reference to FIGS. FIG. 3 shows an image forming process that is switched by the paper type switching device. FIG. 7 shows how a user prints an envelope. FIG. 8 shows an outlet switching device. FIG. 9 shows the relationship between the paper type and the discharge stacking port.

As shown in FIG. 7, this image forming apparatus (laser beam printer in the embodiment) has a paper type switching device A on the front surface of the cassette. 3 (Example 4 in the figure), the optimum transfer process and fixing process are automatically set.

FIG. 8 shows a sheet discharge outlet switching device. The discharge port switching device includes a solenoid 901 and a metal link member 9
02, a solenoid internal spring 903. In the normal state, the spring 903 pushes the link member 902, and the linked flapper 605 is in the solid line state in the figure. When the user has set the switching device for envelopes as shown in Fig. 7, the signal from the paper type switching device is the controller (not shown).
Then, a current is passed through the solenoid 901. As a result, the metal link member 902 moves in the direction of the arrow so as to compress the spring 903, and the flapper 605 connected to the link member rotates. As a result, the conveying path of the recording material is switched from the face-down sheet discharge direction (A) to the face-up sheet discharge direction (A), and the envelope on which the unfixed image is fixed is discharged to the face-up tray 703.

As the user switches the paper type switching device in this way, the paper ejection port switching device operates as the flapper 6
05 is moved to switch to a conveyance path suitable for the recording material, and the recording material is discharged to the discharge stacking port (FIG. 10) suitable for the type of recording material.

When the user switches the switch according to the type of sheet material to the above-mentioned configuration, the discharge port suitable for the recording material is automatically set, so that the sheet material is clogged inside the image forming apparatus, It is possible to prevent the sheet material from being bent, scratched, or curled.

(Fifth Embodiment) A fifth embodiment of the image forming apparatus of the present invention will be described with reference to FIGS. FIG. 3 shows an image forming process that is switched by the paper type switching device. FIG. 10 shows how a user prints thick paper. FIG. 11 shows a recording material curl correcting means. FIG. 12 shows the relationship between the paper type and the set value of the curl correcting means.

As shown in FIG. 10, this image forming apparatus (laser beam printer in the embodiment) has a paper type switching device A on the front surface of the recording material supplying means, and the user sets the switching device. As a result, the optimum transfer process and fixing process are automatically set as shown in FIG. 3 (Example 5 in the drawing).

The recording material P on which the unfixed image is fixed has its conveyance path switched by the flapper 605, and the second paper discharge roller 701a, roller 701b, solenoid 701.
c, metal stopper 701d, cam 701e, curl correction spring 701f, spring receiver 701g ultrasonic sensor 7
The recording material P is conveyed to the recording material curve straightening means (FIG. 12) composed of 01h, and the recording material P is corrected in the recording material curve straightening means of FIG.
Is curled by being sandwiched between the second paper discharge roller 701a and the roller 701b.
It is discharged to 2.

FIG. 10 shows a state in which the user has set a normal size thick paper. At this time, the controller (not shown) confirms the distance from the sensor measured by the ultrasonic sensor 701h to the spring receiver 701g based on the signal from the paper type switching device. After that, a current is applied to the solenoid 701e to move the metal stopper 701d in the direction of the arrow in the figure, and then the cam 701 connected to the motor (not shown).
By rotating e, the contacting spring receiver 701g is moved up and down. By monitoring the signal from the ultrasonic sensor 701h, the controller moves the metal stopper 701d at the point where the spring receiver 701g rises to move the cam 701.
Stop the rotation of e. As a result, the pressing force F increases.

As shown in FIG. 12, the pressing force F is increased for thick paper and the pressing force F is decreased for thin paper, and the curl correction setting changes according to the thickness of the recording material.

As a result, the curl of the thick recording material P, which has been insufficiently corrected in the past, is corrected to a shape close to a plane,
Thereafter, the face-down tray 702 is discharged and stacked.

With the above structure, the user can switch the setting of the curl correcting means for each recording material by switching the switch depending on the type of the sheet material, and a stable curl correcting effect can be obtained, so that the sheet material at the discharge port can be obtained. It is possible to improve the stackability of the sheet and to easily handle the sheet material after printing.

[0079]

As is apparent from the above description, according to the image forming apparatus of the present invention, the optimum mode of the transfer process and the fixing process is automatically determined by the user switching the switch depending on the type of the sheet material. Therefore, due to improper transfer / fixing process due to improper setting of recording material, part of toner is not transferred to recording material and image may be missing, or sufficient heat may not be transferred to recording material. It is possible to prevent the image quality from being deteriorated such that the toner is not fixed on the recording material and the heater unit from being damaged due to the temperature rise at the end of the fixing device, and it is possible to form an image on various sheet materials.

Further, by mounting the switching device on the cassette on which the sheet material is loaded, it is possible to save the trouble of changing the setting of the sheet material each time the cassette is replaced, and the image in the transfer process and the fixing process which is optimal for each cassette is saved. Can be formed.

Further, by mounting the switching device on the recording material supplying means for supplying the sheet material, even when the various kinds of sheet materials such as a multi-stage cassette are sorted and stacked, the cassettes in the respective recording material supplying means are provided. It is possible to form an image in an optimal transfer process and fixing process for each sheet material stacked on the sheet.

Further, since the user manually switches the switch depending on the type of the sheet material, the sheet material discharge port is automatically switched, so that the sheet material inside the image forming apparatus is clogged or the sheet material is broken due to improper selection of the discharge port. -It becomes possible to prevent scratches and curling of the sheet material.

Further, since the user manually switches the switch depending on the type of the sheet material, the curl straightening setting is changed for each recording material, so that the curl straightening effect can be obtained for any recording material. The stackability of the sheet is improved, and the sheet material after printing is easily handled.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a paper type switching device according to a first embodiment.

[Fig. 2] Configuration diagram of a ceramic heater

FIG. 3 is a diagram illustrating an image forming process that is switched by a paper type switching device.

FIG. 4 is a configuration diagram of a paper type switching device according to a second embodiment.

FIG. 5 is a configuration diagram of a paper type switching device according to a third embodiment.

FIG. 6 is a diagram showing a transfer process.

FIG. 7 is a configuration diagram of a paper type switching device according to a fourth embodiment.

FIG. 8 is a configuration diagram of an outlet switching device according to a fourth embodiment.

FIG. 9 is a diagram showing the relationship between paper types and outlets.

FIG. 10 is a configuration diagram of a paper type switching device according to a fifth embodiment.

FIG. 11 is a configuration diagram of a curl correcting unit according to a fifth embodiment.

FIG. 12 is a diagram showing a relationship between a paper type and a curl correcting unit.

FIG. 13 is a configuration diagram of an image forming apparatus according to the present invention.

FIG. 14 is a sectional view of an image forming apparatus according to the present invention.

FIG. 15 is a block diagram of the control panel of FIG.

[Explanation of symbols]

P recording material F Applied pressure T toner A Paper type switching device 1 Printer body 2 paper feed cassettes 5 scanner 6 fixing device 201 sheet stacking board 202 pickup roller 203a Paper feed roller 203b retard roller 203 Paper feed roller pair 301a First transport roller 301b The first mouth 301 First conveying roller pair 301a Second transport roller 302b Second transport roller 302 Second transport roller pair 401 transfer photoconductor 402 transfer roller 403 Transfer Guide 601 heater unit 601a Ceramic heater 601b Heating element (for normal use) 601c Heating element (for small size) 602 pressure roller 603 First pair of discharge rollers 603a First discharge roller 603b Paper exit 605 flapper 701 Second discharge roller pair 701a Second discharge roller 701b Second mouth 701c solenoid 701d stopper 701e cam 701f pressure spring 701g spring receiver 701h Ultrasonic sensor 702 Face down tray 703 Face-up tray 901 solenoid 902 Link member 903 spring

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B65H 29/70 B65H 29/70 3F054 31/00 31/00 Z 3F343 G03G 15/16 103 G03G 15/16 103 5C074 21/00 376 21/00 376 384 384 21/14 H04N 1/29 F H04N 1/29 G03G 21/00 372 F Term (reference) 2C061 AP03 AP04 AQ06 AS02 HJ04 HK07 HN18 2H027 DA12 DA32 DC02 DC11 DC19 DE03 DE04 DE07 DE09 EA03 EA12 EC06 EC18 ED17 ED19 ED22 ED24 ED25 ED29 EE01 EE07 EF06 FA35 FB06 GA01 GA03 GA12 GA34 GA45 GA56 ZA07 2H033 AA02 AA14 AA15 AA29 BA07 BA10 BA12 BA16 BA22 BA27 BA30 BA59 BE03 CA04 CA07 CA09 CA16 CA17 CA20 CA30 CA35 CA44 2H200 FA18 FA19 GA02 GA03 GA04 GA06 GA10 GA14 GA23 GA44 GB26 GB30 HA02 HB12 HB22 JA02 JA28 JA29 JA30 NA02 NA08 PA06 PA15 PA18 PA25 PA27 PB07 PB25 PB37 PB38 3F053 EA02 EA04 EA05 EC01 ED12 ED15 HA03 HB22 LA02 LA05 LA07 LB03 3F054 AA01 AC02 AC03 AC05 BB21 BE00 BF01 BF08 BF22 CA04 3F343 FA01 FB02 FB03 FB04 FC05 FC17 FC19 HA33 HC11 HC26 HD07 KB03 KB20 MA26 MC14 MC30 5C074 AA15 BB03 BB17 CC26 EE02 EE08 HH02

Claims (10)

[Claims] 1. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
A fixing unit for fixing an unfixed image on a recording material, and an image forming apparatus having a plurality of heating elements in the fixing unit,
At least the recording material type switching means for manually switching the recording material type is mounted on the recording material stacking means, and the energization to the plurality of heat generating elements is switched according to the setting of the recording material type switching means. Image forming apparatus. 2. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
In an image forming apparatus having a fixing unit for fixing an untouched image on a recording material and a plurality of heating elements in the fixing unit,
The recording material supply means is equipped with at least a recording material type switching means for manually switching the recording material type, and energization to the plurality of heating elements is switched according to the setting of the recording material type switching means. Image forming apparatus. 3. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
In an image forming apparatus having a fixing means for fixing an unfixed image on a recording material, the recording material stacking means has at least a recording material type switching means for manually switching the recording material type, and the recording material type switching An image forming apparatus characterized in that the heating element is controlled to an optimum temperature for a recording material according to the setting of the means. 4. A recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an image forming means for forming an unfixed image on the recording material.
In an image forming apparatus having a fixing unit for fixing an unfixed image on a recording material, the recording material supply unit has at least a recording material type switching unit for manually switching the recording material type, and the recording material type switching An image forming apparatus characterized in that the heating element is controlled to an optimum temperature for a recording material according to the setting of the means. 5. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
In an image forming apparatus having a fixing means for fixing an unfixed image on a recording material, the recording material stacking means has at least a recording material type switching means for manually switching the recording material type, and the recording material type switching According to the setting of the means, when the image on the photosensitive drum in the image forming means is transferred to the recording material, the transfer voltage for charging the recording material is controlled to an optimum value for the recording material. Image forming apparatus. 6. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
In an image forming apparatus having a fixing unit for fixing an unfixed image on a recording material, the recording material supply unit has at least a recording material type switching unit for manually switching the recording material type, and the recording material type switching According to the setting of the means, when the image on the photosensitive drum in the image forming means is transferred to the recording material, the transfer voltage for charging the recording material is controlled to an optimum value for the recording material. Image forming apparatus. 7. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
A fixing unit for fixing the unfixed image on the recording material; a first discharging and stacking unit for discharging and stacking the recording material on the front side; a second discharging and stacking unit for discharging and stacking the recording material on the back side; In the image forming apparatus having the discharging and stacking means and the discharge switching means for switching the conveyance of the recording material to the second discharging and stacking means, the recording material kind switching for manually switching at least the kind of the recording material to the recording material stacking means. Image forming, characterized by including a means, and switching the discharge switching means in response to a signal from the recording material type switching means to change the conveyance of the recording material to a discharge stacking means suitable for the recording material. apparatus. 8. A recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
A fixing unit for fixing the unfixed image on the recording material; a first discharging and stacking unit for discharging and stacking the recording material on the front side; a second discharging and stacking unit for discharging and stacking the recording material on the back side; In the image forming apparatus having the discharging and stacking means and the discharging switching means for switching the conveyance of the recording material to the second discharging and stacking means, the recording material type switching for manually switching at least the type of the recording material to the recording material supply means. Image forming, characterized by including a means, and switching the discharge switching means in response to a signal from the recording material type switching means to change the conveyance of the recording material to a discharge stacking means suitable for the recording material. apparatus. 9. A recording material stacking means for stacking a plurality of recording materials, a recording material supplying means for supplying the recording materials to the image forming means, and an image forming means for forming an unfixed image on the recording materials.
In an image forming apparatus having a fixing unit for fixing an unfixed image on a recording material and a curl correcting unit for correcting the curl of the recording material caused by the fixing unit, at least the type of the recording material is set in the recording material stacking unit. An image forming apparatus having a recording material type switching means for manually switching, and performing control for changing the setting of the curl correcting means according to a signal from the recording material type switching means. 10. A recording material stacking means for stacking a plurality of recording materials, a recording material supply means for supplying the recording material to the image forming means, and an image forming means for forming an unfixed image on the recording material.
In an image forming apparatus having a fixing means for fixing an unfixed image on a recording material and a curl correcting means for correcting the curl of the recording material caused by the fixing means, at least the kind of the recording material is added to the recording material supplying means. An image forming apparatus having a recording material type switching means for manually switching, and performing control for changing the setting of the curl correcting means according to a signal from the recording material type switching means.