JP2000305385A - Fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing device whose fixing ability is improved by preliminarily heating an image forming substance on material to be recorded by a non-contact heating an means before fixing it by a heating pressuring type fixing part. SOLUTION: In this fixing device 1, an infrared irradiation part 20 is disposed before a heat roll type fixing part 10 in a carrying direction of transfer paper 40 carried by a carrying mechanism 30. In the irradiation part 20, infrared rays from an infrared lamp 21 directly irradiate the surface of the transfer paper 40 carried by a transparent carrying belt 33 and are reflected on an infrared reflection mirror 22 to irradiate the surface of the transfer paper 40, and the infrared rays passing through the part of the belt 33 where the paper 40 does not pass are reflected by a reflector 23 to irradiate the rear surface of the paper 40 on the belt 33. In a heat roller type fixing part 10, the paper 40 heated to specified temperature by the irradiation part 20 is heated and pressured by a heating roller 11 heated by a heat source 13 and a pressure roller 12, so that unfixed toner 50 is fixed on the paper 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device and an image forming apparatus, and more particularly, to an image formed of a heat-fusible image forming material formed on a recording material such as paper by an electrophotographic recording system. And a fixing device for heating the recording material as a permanently fixed image on a recording material.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus such as a copying machine, a facsimile machine and an electrophotographic printer,
The toner (image forming substance) electrostatically transferred from the photoreceptor to a recording material such as paper is easily peeled off. Therefore, it is necessary to permanently fix the toner to the recording material by heating or pressing the toner. Becomes This step is called a fixing process, and there are various fixing methods, for example, a heat roller method in which a recording material is sandwiched and heated by a heating roller and a pressure roller while heating and fixing are performed. There is a film heating method using a heating body having a heat capacity and a fixing film.

[0003] Today, there is a demand for energy saving, and various energy saving measures are also taken for fixing devices.

For example, in a heat roller type fixing device, the heat capacity is reduced by reducing the thickness of the heat roller, the startup time is shortened, and the heating of the roller during standby is suppressed to a minimum temperature. ing. In a low-speed image forming apparatus, a film heating method using a heating element having a low heat capacity and a fixing film is adopted as a fixing device.
Energy consumption during standby is greatly reduced.

However, in the heat roller method, when a recording material having a small size is continuously fixed, a heating roller portion (sheet passing area) where the recording material comes into contact and a heating roller portion where the recording material does not contact (a non-heating roller portion). (A paper passing area), there is a difference in the amount of heat radiation. That is, the heat is not taken away by the recording material because the recording material does not pass, and the surface temperature of the heating roller portion (non-sheet passing area portion) through which the recording material does not pass is set by the recording material passing through. A so-called non-sheet-passing portion temperature rise phenomenon occurs that is higher than the surface temperature of the heating roller portion (sheet passing area portion) through which the recording material from which heat is taken away by the material passes.

Therefore, in a fixing device of the heat roller type, usually, the surface temperature of the heating roller at a position where recording materials of all available sizes always pass is detected, and the temperature of the heating roller is set to a predetermined fixing temperature. Although the temperature is controlled, the use state in which the non-sheet passing portion temperature rising phenomenon frequently occurs, that is, the fixing operation of the recording material having a size smaller than the maximum usable recording material is continuously performed. After that, when the recording material is switched to a recording material having a size larger than the size, the temperature of the heating roller surface in the non-paper passing area is considerably higher than that of the heating roller surface in the paper passing area. , And a so-called high-temperature offset sometimes occurred. In particular, this is remarkable in a roller having a low heat capacity due to thinning or the like.

In the film heating method, when a small-sized recording material is continuously passed through the paper and heated and fixed, an excessive amount of non-paper passing over the heating element and the film is performed by the same mechanism as in the heat roller method. When the temperature rise phenomenon occurs and the heat fixing process is performed by passing the large-sized recording material after the continuous passing of the small-sized recording material, the high-temperature offset may occur in the same manner as described above. In addition, there has been a problem that heat damage to the heating element or the film, reduction in the durability life, instability of the running property, and the like occur.

That is, the heating element used in the film heating method has a heat generating layer whose longitudinal direction is perpendicular to the moving direction of the recording material, and electrodes provided on both ends of the heat generating layer. , Each portion of the effective entire length region of the heat generating layer generates heat at a predetermined heat value per unit length. The effective heat generation area has a size corresponding to the width of the recording material having the maximum size that can be fixed by the fixing device.

However, in such a heating element, regardless of the size of the recording material to be used, the heating layer generates heat over the entire effective heat generation area, and when the size of the recording material is small,
In the heat generating layer area (non-sheet passing area) through which the recording material does not pass, most of the generated thermal energy is stored without being consumed,
The temperature of the heating element in the non-sheet passing area rises abnormally, causing various problems such as high-temperature offset, thermal damage to the heating element and the film, reduction in the durability life, and instability of the running property.

In particular, in the case of a film heating method in which a heating element having a low heat capacity can be used as the heating element, the heat capacity of the heating element is smaller than that of the heat roller method. In addition to the large size, high-temperature offset easily occurs, and problems such as film drive instability and film wrinkling are likely to occur. The above problem becomes more remarkable as the paper passing speed is increased.

Therefore, conventionally, a fixing device in which an aluminum roller is brought into contact with a pressure roller to absorb and radiate excess heat to prevent a temperature rise in a non-sheet passing portion of a film heating system (Japanese Patent Laid-Open No.
Japanese Patent Application Laid-Open No. 5-13584), a plurality of sensors and a plurality of sensors are provided to control energization of a heater portion to prevent a temperature rise in a non-paper passing portion of a film heating system.
No. 8) has been proposed.

Further, in order to prevent a paper conveyance failure from occurring due to a difference in thermal expansion when a temperature rise in the non-sheet passing portion, a roller type of an electromagnetic induction heating system having a plurality of winding layers in a core portion is provided. A fixing device has been proposed (see JP-A-10-10901).

[0013]

However, such a conventional fixing device has the following problems. That is, in the prior art described in Japanese Patent Application Laid-Open No. 9-80941, since an aluminum roller is brought into contact with a pressure roller to absorb and radiate excess heat, an aluminum roller needs to be provided, and the structure is complicated and expensive. In addition, the extra heating itself is useless in the first place, and there is a need for improvement in order to save energy.

In the prior art described in Japanese Patent Application Laid-Open No. 5-135848, since a plurality of sensors are provided to control the energization of the heater, a large number of sensors are required and the control system becomes complicated. In addition, there is a need for improvement in stabilizing the operation and a problem that the cost is increased.

Furthermore, the prior art described in Japanese Patent Application Laid-Open No. 10-10901 has a problem that the device becomes large and expensive because a plurality of winding layers are provided in the core portion.

In particular, today, there is a demand for higher processing speed and energy saving, and there is a demand for an inexpensive and stable fixing device that appropriately responds to these demands.

Therefore, according to the first aspect of the present invention, a predetermined electromagnetic wave is irradiated before the heating / pressing type fixing unit to heat the recording material and the unfixed image forming material to a predetermined temperature in a non-contact state. A non-contact heating unit is provided, and a conveyance belt for conveying the recording material is formed of a member that transmits electromagnetic waves, and the electromagnetic wave emitted from the non-contact heating unit is recorded before being conveyed to the heating / pressing type fixing unit. Along with irradiating the surface of the recording material, it is also reflected by the reflection member and irradiates the back surface of the recording material,
By preheating the recording material and the image forming material conveyed to the heating and pressing type fixing unit, the rising speed of the fixing device is increased, and the temperature of the non-sheet passing portion of the transfer paper of the heating and pressing type fixing unit is increased. It is an object of the present invention to provide an inexpensive fixing device that can reduce the number of fixing devices, improve the stability in high-speed operation, and improve the fixing performance.

According to a second aspect of the present invention, the heating / pressing type fixing unit includes a heating roller heated to a predetermined temperature, and a pressure roller contacting the heating roller at a predetermined pressure. A roller-type fixing unit is used in which at least one of the rollers is driven to rotate and heat-presses while fixing a recording material conveyed by a conveyance mechanism between the heating roller and the pressing roller to fix the image forming material. As a result, a stable roller-type fixing unit can quickly respond to high-speed operation while reducing the rise in temperature of the non-sheet passing portion of the transfer sheet of the heating roller, thereby improving the stability at high-speed operation. It is an object of the present invention to provide an inexpensive fixing device capable of improving fixing performance.

According to a third aspect of the present invention, a heating roller heated by electromagnetic induction heating is used without complicating the structure of the heating roller for electromagnetic induction heating having a good rising speed. It is an object of the present invention to provide a fixing device capable of reducing the temperature rise of the non-sheet passing portion of the transfer paper, further improving the stability in high-speed operation, and improving the fixing performance.

According to a fourth aspect of the present invention, the heating / pressing type fixing unit includes a heating film heated to a predetermined temperature, and a pressure roller contacting the heating film at a predetermined pressure. By using a film-type fixing unit that is driven and heated and pressed to fix an image forming substance while conveying a recording material conveyed by a conveyance mechanism between the heating film and the pressure roller, the heat capacity is low. An inexpensive fixing device that can reduce the temperature rise of the non-sheet passing area of the transfer paper of the film type fixing unit, improve the startup speed while further reducing energy consumption, and improve the fixing performance. It is intended to provide.

According to a fifth aspect of the present invention, an image forming material and a recording material are heated more efficiently by using a non-contact heating means which irradiates infrared rays as electromagnetic waves, and the stability at high speed operation is improved. It is an object of the present invention to provide a fixing device that can further improve the fixing performance and improve the fixing performance.

According to a sixth aspect of the present invention, the use of a means for irradiating electromagnetic waves with a flash lamp as the non-contact heating means further reduces burning of the recording material and further improves the stability. It is an object of the present invention to provide a fixing device that can perform the fixing.

According to a seventh aspect of the present invention, the conveying mechanism conveys the recording material in a direction orthogonal to the conveying direction of the recording material by the conveying belt, with the recording material conveyed to one side, and the non-contact heating means. The reflection member is disposed at the end of the conveyor belt opposite to the side on which the recording material is moved, so that the recording material is conveyed on a so-called one-side basis, and recording is performed. It is an object of the present invention to provide a fixing device in which a reflecting member is provided only on the non-sheet passing portion side of a material, the configuration is further simplified, and the cost is further reduced.

According to an eighth aspect of the present invention, the non-contact heating means includes an angle adjusting mechanism for adjusting the inclination angle of the reflecting member according to the size of the recording material.
It is an object of the present invention to provide a fixing device capable of appropriately reflecting electromagnetic waves incident on a reflecting member in the direction of a recording material regardless of the size of the recording material and further reducing energy consumption.

According to a ninth aspect of the present invention, the heating and pressurizing type fixing unit is provided with a temperature control unit for adjusting a heating temperature in accordance with the size of the recording material. Provided is a fixing device capable of imparting appropriate heat to a recording material and an image forming material regardless of the size of the recording material to further improve fixing performance and further reducing energy consumption. It is intended to be.

[0026]

According to a first aspect of the present invention, there is provided a fixing device, wherein a recording material to which an unfixed image forming material is adhered is heated and pressurized while conveying the recording material to which the image forming material is adhered. A fixing mechanism provided with a heating and pressing type fixing unit for fixing the recording medium to the heating and pressing type fixing unit, and the recording medium conveyed to the heating and pressing type fixing unit by the conveying mechanism. A non-contact heating unit that irradiates a predetermined electromagnetic wave to the material from an electromagnetic wave irradiation unit and heats the recording material and the unfixed image forming material to a predetermined temperature in a non-contact state, and the transport mechanism includes: The recording medium is placed and transported to the heating and pressing type fixing unit, and a transport belt that transmits the electromagnetic wave irradiated by the non-contact heating unit is provided. The non-contact heating unit sandwiches the transport belt. The above The recording material, which is disposed at a position opposite to the wave irradiating means, and which is radiated from the electromagnetic wave irradiating means and transmits the electromagnetic wave transmitted through the non-passing portion of the recording material of the transport belt by the transport belt. The above object is achieved by providing a reflecting member that reflects light in the direction.

According to the above arrangement, a non-contact heating means for irradiating a predetermined electromagnetic wave to heat the recording material and the unfixed image forming material to a predetermined temperature in a non-contact state before the heating / pressing type fixing unit. The transport belt for transporting the recording material is formed of a member that transmits electromagnetic waves, and before being transported to the heating / pressing type fixing unit, the electromagnetic waves emitted from the non-contact heating unit are applied to the surface of the recording material. The recording material and the image forming material conveyed to the heating / pressing type fixing unit are preheated by irradiating the recording material and being reflected by the reflection member and irradiating the back surface of the recording material, so that the rising speed of the fixing device is increased. It is possible to reduce the temperature rise in the non-sheet passing area of the transfer paper of the heating and pressing type fixing unit, improve the stability at high speed operation, and improve the fixing performance. Cheap It is possible to provide a wearing device.

In this case, for example, as set forth in claim 2, the heating / pressing type fixing unit includes a heating roller heated to a predetermined temperature, and a pressure roller contacting the heating roller at a predetermined pressure. Wherein at least one of the heating roller and the pressure roller is rotationally driven to heat and pressurize while conveying the recording material conveyed by the conveyance mechanism between the heating roller and the pressure roller. It may be a roller type fixing section for fixing the image forming substance.

According to the above configuration, the heating / pressing type fixing unit includes the heating roller heated to a predetermined temperature and the pressure roller contacting the heating roller at a predetermined pressure. A roller-type fixing unit is used in which at least one of the rollers is driven to rotate and heat-presses the recording material conveyed by the conveyance mechanism between the heating roller and the pressure roller while heating and fixing the image-forming substance. So
The stable roller-type fixing unit can be started up quickly and can support high-speed operation, and the temperature rise of the non-sheet passing portion of the transfer sheet of the heating roller can be reduced, improving the stability at high-speed operation. In addition, it is possible to provide an inexpensive fixing device capable of improving the fixing performance.

Also, for example, the heating roller may be heated by electromagnetic induction heating.

According to the above configuration, since a heating roller heated by electromagnetic induction heating is used as the heating roller, the structure of the heating roller of electromagnetic induction heating having a good rising speed is not complicated, and the heating roller is heated. The temperature rise of the non-sheet passing portion of the transfer sheet can be reduced, and the stability in high-speed operation can be further improved, and the fixing performance can be improved.

Further, for example, as set forth in claim 4, the heating-pressing type fixing section includes a heating film heated to a predetermined temperature, and a pressure roller contacting the heating film at a predetermined pressure. A film type in which the image forming material is fixed by heating and pressing while the recording material conveyed by the conveyance mechanism is conveyed between the heating film and the pressure roller by rotating the pressure roller. The fixing unit may be used.

According to the above arrangement, the heating / pressing type fixing section includes a heating film heated to a predetermined temperature, and a pressure roller in contact with the heating film at a predetermined pressure, and the pressure roller is driven to rotate. Since a film-type fixing unit for fixing an image forming material by heating and pressing while transporting a recording material transported by a transport mechanism between the heating film and the pressure roller is used, the film having a low heat capacity is used. An inexpensive fixing device that can reduce the temperature rise of the non-sheet passing portion of the transfer paper in the fixing unit, can further increase the startup speed while further reducing energy consumption, and can improve the fixing performance. An apparatus can be provided.

Also, for example, the non-contact heating means may irradiate infrared rays as the electromagnetic waves.

According to the above-mentioned structure, since the non-contact heating means that irradiates infrared rays as electromagnetic waves is used, the image forming material and the recording material can be heated more efficiently, and the non-contact heating means can operate at high speed. The stability can be further improved, and the fixing performance can be improved.

Further, for example, the non-contact heating means may irradiate the electromagnetic wave by a flash lamp.

According to the above-described structure, since the non-contact heating means that irradiates an electromagnetic wave with a flash lamp is used, the burning of the recording material can be further reduced, and the stability is further improved. be able to.

Further, for example, as set forth in claim 7, the transport mechanism moves the recording material to one side in a direction orthogonal to the transport direction of the recording material by the transport belt. The recording medium may be conveyed in a state, and the reflection member of the non-contact heating means may be provided at an end position of the conveyance belt opposite to the side where the recording material is brought.

According to the above arrangement, the transport mechanism transports the recording material in a direction perpendicular to the direction of transport of the recording material by the transport belt, with the recording material conveyed to one side, and the reflection of the non-contact heating means. Since the member is disposed at the end of the conveyor belt opposite to the side on which the recording material is moved, the recording material is conveyed on a so-called one-side basis, and the non-recording material is transferred. The reflection member can be provided only on the paper passing portion side, so that the configuration can be further simplified and the cost can be further reduced.

Further, for example, as set forth in claim 8, the non-contact heating means includes an angle adjusting mechanism for adjusting the inclination angle of the reflecting member according to the size of the recording material. There may be.

According to the above arrangement, since the non-contact heating means is provided with the angle adjusting mechanism for adjusting the inclination angle of the reflecting member in accordance with the size of the recording material, regardless of the size of the recording material. Electromagnetic waves incident on the reflecting member can be appropriately reflected in the direction of the recording material, and energy consumption can be further reduced.

Further, for example, as described in claim 9, the heating and pressurizing type fixing unit includes a temperature adjusting unit for adjusting the heating temperature according to the size of the recording material. You may.

According to the above configuration, since the heating / pressing type fixing unit having the temperature adjusting unit for adjusting the heating temperature in accordance with the size of the recording material is used, the heating / pressing type fixing unit includes: Appropriate heat can be applied to the recording material and the image forming material regardless of the size of the recording material, so that the fixing performance can be further improved and the energy consumption can be further reduced.

[0044]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 and 2 show the first embodiment of the fixing device of the present invention.
In this embodiment, an infrared irradiating unit is provided as a non-contact heating unit in front of a fixing unit of a heat roller type.

In FIG. 1, the fixing device 1 includes a heat roller type fixing unit 10, an infrared irradiation unit 20, a transport mechanism 30, and the like.
The infrared irradiating section 20 and the heat roller type fixing section 10 are arranged in this order with respect to the conveying direction 0.

It should be noted that the fixing device 1 according to the present embodiment conveys the transfer paper 40 in a state where the center in the width direction coincides with the center in the conveyance direction, that is, so-called center reference (center reference). .

Heat roller type fixing unit (heating / pressing type fixing unit) 1
Reference numeral 0 denotes a state in which a cylindrical heating roller 11 and a pressing roller 12 having a predetermined length are disposed in a state of being pressed against each other.
1 is heated by a heat source 13. As the heat source 13 of the heating roller 11, a halogen lamp or the like is used. The heat source 13 is disposed in the axial direction of the heating roller 11 so as to have a length substantially equal to the entire length of the heating roller 11, and uniformly heats the heating roller 11 in the axial direction. I do.

The surface portion of the heating roller 11 is made of a smooth material such as Teflon to prevent toner from adhering, and the heat from the heat source 13 is transmitted to the surface portion other than the surface portion thereof quickly. Thus, it is made of aluminum. The portions other than the surface layer of the heating roller 11 are:
The material is not limited to aluminum, and may be another material as long as it has a high thermal conductivity and a hardness sufficient to prevent deformation in the axial direction. The heating roller 11 is rotationally driven by a driving mechanism (not shown), and presses and heats the transfer paper 40 conveyed between the heating roller 11 and the pressure roller 12 between the pressure roller 12 and the transfer paper 40. The unfixed toner (image forming substance) 50 is fixed on the recording paper 50. The surface temperature of the heating roller 11 is detected by a temperature sensor (for example, a thermistor or the like) not shown, and the amount of power supplied to the heat source 13 by a control unit (not shown) based on the detection result of the temperature sensor. The temperature is controlled to a predetermined fixable temperature.

In order to prevent the toner 50 from offsetting, at least the outermost surface layer of the heating roller 11 which contacts the toner 50 is made of polyvinylidene fluoride (PVdF),
Polytetrafluoroethylene (PTFE), tetrafluoroethylene-ethylene copolymer (ETFE), polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-hexafluoropropylene copolymer (F
EP) It is formed of a fluorine resin such as tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer (THV).

The pressing roller 12 is pressed against the heating roller 11 by a pressing mechanism (not shown).
The recording paper 50 conveyed to the heating roller 11 is pressed against the heating roller 11 so that the unfixed toner 50 on the recording paper 50 is heated by the heating roller 11.
Is fixed on the recording paper 50 by the heat of.

The heating roller 11 is not limited to the one having the above-described structure, and can be heated at a low temperature as described later. Heat source 13
For example, a surface heating roller provided with a resistance heating element, a roller provided with a coil inside a thin metal roller and heated by electromagnetic induction can be used.

The infrared irradiation section (non-contact heating means) 20
An infrared lamp (electromagnetic wave irradiation means) 21, an infrared reflection mirror 22, a reflection plate (reflection member) 23, and the like are provided. The infrared reflection mirror 22 efficiently reflects infrared light from the infrared lamp 21 toward the transfer paper 40. To irradiate
It is formed in a parabolic or elliptical shape.

The infrared irradiating section 20 directly irradiates infrared rays from an infrared lamp 21 as an electromagnetic wave irradiating means onto the surface of the transfer paper 40 conveyed by a conveying mechanism 30 described later, and reflects the infrared light on an infrared reflecting mirror 22. , Transfer paper 4
In addition, the infrared irradiating unit 20 irradiates the surface of the transfer paper 40 with the infrared light that has passed through the side portion (non-sheet passing portion) of the transfer paper 40.
The transfer paper 40 and the toner 50 are heated to a predetermined temperature by irradiating the back surface of the transfer paper 40 conveyed by the conveyance mechanism 30 after being reflected by the transfer mechanism 30.

The toner 50, which is an image forming substance, is usually mainly composed of a resin component, a coloring agent, a polarity control agent, and the like. Examples of the resin component include a styrene resin, an acrylic resin, and a methacrylic resin. Resins, styrene-acrylic copolymers, styrene-butadiene copolymers, thermoplastic resins and thermosetting resins such as polyester resins and epoxy resins, or a mixture of two or more of these resins are used. Have been. These resins generally have a glass transition temperature of 55 ° C to 70 ° C,
The softening point is 70C to 140C.

The toner 50 and the transfer paper 40 have an absorption region in the infrared region, absorb the infrared light irradiated by the infrared irradiation unit 20, and are efficiently heated.

The infrared irradiating section 20 uses an infrared lamp 21 as an electromagnetic wave irradiating means. However, the electromagnetic wave irradiating means is not limited to this. A heater, a xenon lamp, or the like coated with a ceramic may be used. In particular, if a flash heating method using a xenon lamp is employed as the electromagnetic wave irradiation means, the possibility of burning of the transfer paper 40 and the like can be reduced, and safety can be improved.

The transport mechanism 30 includes a pair of transport rollers 31,
32, a transparent transport belt 33, and the like. The transparent transport belt 33 is formed in a ring shape having a predetermined width, and is stretched over the transport roller 31 and the transport roller 32. The transparent transport belt 33 has a transparency suitable for transmitting infrared rays, and is formed of a material having heat resistance enough to withstand the heating by the infrared irradiation unit 20. For example, polyimide (P
I), tetrafluoroethylene-ethylene copolymer (E
TFE), polyphenylene sulfide (PPS) and the like are used.

In the transport mechanism 30, at least one of the transport roller 31 and the transport roller 32 is driven to rotate counterclockwise in FIG. 1 by a drive mechanism (not shown), and the transparent transport belt 33 is driven to rotate counterclockwise in FIG. Transfer paper 40 conveyed from the feeding mechanism to the transparent conveyance belt 33
Is passed through the infrared irradiating section 20 and the heat roller type fixing section 1
Transport to 0.

Next, the operation of this embodiment will be described. The fixing device 1 includes a transfer paper 40 transported by the transport mechanism 30.
An infrared irradiator 20 is disposed in front of the heat roller type fixing unit 10 in the conveying direction of the heat roller. After the infrared irradiator 20 performs preheating, the heat roller type fixing unit 10 heats and presses to fix. There is a characteristic.

That is, the fixing device 1 conveys the transfer paper 40 on which an image is formed by attaching the toner 50 in an image forming unit (not shown) to the heat roller type fixing unit 10 by the conveying mechanism 30, The light passes through the irradiation unit 20.

The infrared irradiating section 20 receives the infrared light from the infrared lamp 21 and transfers the transfer paper 40 conveyed by the conveying mechanism 30.
Directly irradiates the surface of the
And irradiates the surface of the transfer paper 40 with the infrared ray irradiating unit 20. The infrared irradiating unit 20 reflects the infrared light that has passed through the side (non-sheet passing portion) of the transfer paper 40 of the transparent transport belt 33 with the reflection plate 23. Irradiates the back surface of the transfer paper 40 conveyed by the conveyance mechanism 30.

Accordingly, the transfer paper 40 is conveyed to the heat roller type fixing unit 10 while being heated to a predetermined temperature by the infrared irradiation unit 20.

The heat roller type fixing section 10 includes an infrared irradiation section 2
The transfer paper 40 that has been heated to a predetermined temperature by 0 and transported by the transport mechanism 30 is heated and pressed by the heating roller 11 and the pressure roller 12 that are heated by the heat source 13, and the unfixed toner 50 is transferred to the transfer paper 40. To be established.

At this time, the transfer paper 40 and the unfixed toner 5
In the case of 0, since the heating is already performed by the infrared irradiation unit 20, the amount of heat required for heating by the heat roller type fixing unit 10 can be reduced. That is, normally, in order to heat and fix the toner 50 to the transfer paper 40 only by the heat roller type fixing unit 10, all the necessary heat must be supplied from the heat roller 11. ~ 190 ° C
And need to be high temperature. Further, when the transfer paper 40 passes between the heating roller 11 and the pressure roller 12,
Although the temperature of the heating roller 11 decreases, the temperature of the heating roller 11 having a low heat capacity decreases significantly, and a paper passing portion where the transfer paper 40 of the heating roller 11 passes and a non-paper passing portion where the transfer paper 40 does not pass. And the temperature difference between them increases. On the other hand, in the fixing device 1, since the transfer paper 40 conveyed to the heat roller type fixing unit 10 is already heated by the infrared irradiation unit 20, the amount of heat supplied by the heating roller 11 may be small. Therefore, in the fixing device 1, the temperature of the heating roller 11 can be reduced, power consumption can be reduced, and a decrease in the temperature of the heating roller 11 due to paper passing can be suppressed. By reducing the temperature difference between the heating rollers 11 in the paper passing portion, it is possible to prevent the temperature in the non-paper passing portion from abnormally rising, and to improve the fixing performance.

The infrared irradiating section 20 includes a transport mechanism 30
Since the reflection plate 23 is disposed below the transfer paper 40 conveyed by the above, the back surface side of the transfer paper 40 is heated by infrared rays that have passed through a portion (non-sheet passing portion) through which the transfer paper 40 does not pass. The heat of the infrared lamp 21 as a heat source can be effectively used, and power consumption can be reduced.

Furthermore, the infrared lamp 21 of the infrared irradiating section 20 and the heat roller fixing section 10 having a low heat capacity have a fast rising speed, do not require preheating, can further reduce power consumption, and have a heat roller type fixing section. Since the heating temperature of the heating roller 11 of the section 10 can be lowered,
The rising speed can be further increased, the waiting time can be further reduced, and the usability of the fixing device 1 can be improved.

Further, the fixing device 1 can apply a sufficient amount of heat to the transfer paper 40 by the infrared irradiating section 20, and can increase the conveying speed of the transfer paper 40 to improve the fixing speed.

Further, in the case where a roller provided with a coil inside a thin metal roller and heated by electromagnetic induction is used as the heating roller 11, conventionally, in order to reduce the temperature rise in the non-sheet passing portion, the winding of the coil is conventionally used. A plurality of transfer papers 40 are provided.
Because the energization to the through coil was changed for each size of
Although the structure of the heating roller was complicated, in the present embodiment, since the temperature of the paper passing portion is small as described above, the heating roller 11 is provided with a coil inside a thin metal roller and heated by electromagnetic induction. Also in the case of using a roller that makes it possible, the temperature rise of the non-sheet passing portion can be suppressed without complicating the structure of the heating roller 11, and the fixing device 1 can be made small and inexpensive.

FIG. 3 is a view showing a second embodiment of the fixing device according to the present invention. In this embodiment, an infrared irradiation unit is provided as a non-contact heating means in front of a film fixing type fixing unit. It was established.

In the description of the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 3, the fixing device 60 includes a film-type fixing unit 70, an infrared irradiating unit 20, a transport mechanism 30, and the like. The transport mechanism 30 moves the transfer paper 40 as a recording material in the transport direction. , An infrared irradiation unit 20 and a film-type fixing unit 70 in this order.

The infrared irradiating section 20 and the transport mechanism 30 are the same as in the first embodiment, and a detailed description thereof will be omitted.

The film-type fixing section 70 includes a fixing film 7
1, a heating element 72, a pressure roller 73, and the like. As the heating element 72, for example, a ceramic heater or the like that efficiently heats with a low heat capacity is used. Fixing film 7
Reference numeral 1 denotes a transfer paper 40 which is formed in a ring shape having a width at least equal to or larger than the maximum size of the transfer paper 40, is arranged so as to surround the heating element 72, and is conveyed between the transfer roller 40 and the pressure roller 73. Rotates in the direction indicated by the arrow in FIG.

In order to prevent the offset of the toner 50, at least the outermost surface layer of the fixing film (heated film) 72 in contact with the toner 50 is made of polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTD).
FE), tetrafluoroethylene-ethylene copolymer (ETFE), polychlorotrifluoroethylene (PC
TFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP) tetrafluoroethylene-
It is formed of a fluororesin such as hexafluoropropylene-vinylidene fluoride copolymer (THV).

The pressure roller 73 is disposed so as to face the heating element 72 with the fixing film 71 interposed therebetween, and presses the conveyed transfer paper 40 against the fixing film 71.

The film-type fixing section 70 heats the transfer paper 40 conveyed by the conveying mechanism 30 and heated by the infrared irradiating section 20 by the heating element 72 via the fixing film 71 and between the transfer paper 40 and the pressure roller 73. To fix the unfixed toner 50 on the transfer paper 40 to the transfer paper 40.

The film-type fixing section 70 is not limited to the one in which the heating element 72 is brought into contact with the inner peripheral surface of the fixing film 71 as in the present embodiment. For example, a metal layer may be provided, and the film may be heated by electromagnetic induction.

Next, the operation of the present embodiment will be described. The fixing device 60 is configured to transfer the transfer paper 4 transported by the transport mechanism 30.
The infrared irradiating section 20 is disposed in front of the film fixing section 70 in the transport direction of 0, and the preheating is performed by the infrared irradiating section 20, and the film is fixed by heating and pressing in the film fixing section 70. There is a feature.

That is, the fixing device 6 conveys the transfer paper 40 on which the image is formed by attaching the toner 50 in an image forming unit (not shown) to the film type fixing unit 60 by the conveying mechanism 30, and irradiates the infrared light on the way. Pass through section 20.

The infrared irradiating section 20 directly irradiates infrared rays from the infrared lamp 21 onto the surface of the transfer paper 40 conveyed by the conveying mechanism 30 as described above, and reflects the infrared rays from the infrared reflecting mirror 22 to transfer the infrared rays. The infrared light irradiating unit 20 irradiates the front surface of the paper 40, and irradiates the back surface of the transfer paper 40 conveyed by the conveyance mechanism 30 by reflecting the infrared light that has passed through the side of the transfer paper 40 with the reflection plate 23. .

Accordingly, the transfer paper 40 is conveyed to the film fixing unit 70 while being heated to a predetermined temperature by the infrared irradiation unit 20.

The film-type fixing unit 70 includes the infrared irradiation unit 2
The transfer paper 40 which has been heated to a predetermined temperature by 0 and transported by the transport mechanism 30 is heated by a heating member 72 via a fixing film 71 and pressed by a pressure roller 73 to transfer the unfixed toner 50 to the transfer paper. Fix to 40.

At this time, the transfer paper 40 and the unfixed toner 5
In the case of “0”, since the heating is already performed by the infrared irradiation unit 20, the amount of heat required for heating in the film fixing unit 70 can be reduced.

Further, when the transfer paper 40 passes between the heating element 72 and the pressure roller 73 via the fixing film 71, the temperature of the fixing film 71 decreases. Since the transfer paper 40 conveyed to the unit 70 has already been heated by the infrared irradiation unit 20, it is possible to suppress a decrease in the temperature of the fixing film 71 due to the passage of the transfer paper 40, and to prevent the transfer paper 40 from passing therethrough. The temperature rise of the fixing film 71 in the paper passing portion can be suppressed.

That is, the film fixing unit 70 is effective as an energy-saving fixing method because it has a low heat capacity and has a quick rise and does not require preheating. When the temperature of the fixing film 71 rises, local thermal expansion of the fixing film 71 occurs, the running stability of the fixing film 71 deteriorates, and the transfer paper 40 becomes wrinkled or jammed. The deterioration of the running stability of the fixing film 71 and the decrease of the surface temperature of the heating element 72 become remarkable as the processing speed is increased.

However, the fixing device 60 of the present embodiment
Since the infrared irradiation unit 20 is disposed in front of the film-type fixing unit 70 and the transfer paper 40 and the unfixed toner 50 are pre-heated, the heating unit 72 can have a lower heat capacity. Power consumption can be reduced, and a temperature difference between a paper passing portion of the fixing film 71 through which the transfer paper 40 passes and a non-paper passing portion through which the transfer paper 40 does not pass is reduced. It is possible to prevent the portion from rising abnormally, improve the running stability of the fixing film 71, and prevent the transfer paper 40 from wrinkling or jamming. Therefore, even when high-speed processing is performed, fixing performance can be improved.

FIG. 4 is a view showing a third embodiment of the fixing device according to the present invention. In this embodiment, the transfer paper is transported with one side in the width direction of the transfer paper and one side in the transport direction. Do
The configuration of the infrared irradiator is changed in accordance with the so-called one-sided conveyance.

This embodiment is applied to a fixing device similar to the first or second embodiment, and the same reference numerals as those used in the description of each embodiment are required. The description will be made by using as it is.

FIG. 4 is an enlarged side view of an essential part of the fixing device according to the present embodiment, as viewed from the transfer direction of the transfer sheet of the infrared irradiation section 80. , An infrared reflecting mirror 81 and a reflecting plate 82 are provided.

The infrared reflecting mirror 81 reflects and irradiates infrared rays from an infrared lamp (not shown) toward the surface of the transfer paper 40, and is formed in a parabolic or elliptical shape in order to improve the reflection efficiency. I have.

As shown in FIG. 4, since the transfer paper 40 is conveyed on one side basis, the reflection plate 82 is inclined downward by a predetermined angle below the conveyance belt 33 on the non-sheet passing portion side of the transfer paper 40. The infrared light indicated by the arrow in FIG.
The light is reflected and irradiated on the back side of the. The reflection plate 82 is a transfer paper 4
Only one sheet needs to be provided on the side of the non-sheet passing portion 0.

The fixing device according to the present embodiment includes
The transfer paper 40 conveyed by 3 is directly irradiated with infrared rays from an infrared lamp (not shown), and is irradiated with the infrared rays reflected by the infrared reflection mirror 81. Further, in the fixing device, as described above, since the transfer paper 40 is transported on the basis of one side, the reflection plate 82 is provided only on the non-paper passing portion side of the transfer paper 40, Part of conveyor belt 33
The infrared rays that have passed through are reflected on the back side of the transfer paper 40 and irradiated.

Therefore, the fixing device, particularly the infrared irradiating section 80, can be made simple and inexpensive.

FIGS. 5 and 6 show a fourth embodiment of the fixing device of the present invention.
In the present embodiment, when a transfer sheet is transported on one side basis, the inclination angle of the reflector is adjusted according to the size of the transfer sheet.

This embodiment is applied to a fixing device similar to the first or second embodiment, and the same reference numerals as those used in the description of each embodiment are required. The description will be made by using as it is.

FIGS. 5 and 6 are enlarged side views of a main part of the infrared irradiating unit 90 of the fixing device according to the present embodiment as viewed from the transfer direction of the transfer paper.
The infrared reflection mirror 91 and the reflection plate 92 are disposed with the conveyance belt 33 interposed therebetween.

The infrared reflecting mirror 91 reflects and irradiates infrared rays from an infrared lamp (not shown) toward the surface of the transfer paper 40, and has a parabolic or elliptical shape in order to improve the reflection efficiency. I have.

As shown in FIGS. 5 and 6, since the transfer paper 40 is transported on the basis of one side as shown in FIGS.
5 is disposed below the conveyor belt 33 on the side of the non-sheet passing portion at a predetermined angle and passes through the conveyor belt 33 at the non-sheet passing portion of the transfer paper 40 as indicated by arrows in FIGS. The infrared rays shown are reflected and radiated to the back side of the transfer paper 40.

The reflection plate 92 is attached to an angle adjustment mechanism (not shown), and as shown in FIGS. 5 and 6, the size of the transfer paper 40 conveyed by the conveyance mechanism 30, particularly,
The inclination angle is adjusted by the angle adjusting mechanism according to the width direction size. In addition, since the reflection plate 92 may be provided only on the non-sheet passing portion side of the transfer paper 40, only one reflection plate is provided.

The fixing device of the present embodiment employs the conveyance belt 3
The transfer paper 40 conveyed by 3 is directly irradiated with infrared rays from an infrared lamp (not shown), and is irradiated with the infrared rays reflected by the infrared reflection mirror 91. Further, in the fixing device, as described above, since the transfer paper 40 is transported on the basis of one side, the reflection plate 92 is provided only on the non-paper passing portion side of the transfer paper 40, Part of conveyor belt 33
5 and 6 which have passed through the transfer paper 4
Then, the light is reflected and radiated to the back surface side of 0.

In the fixing device, the reflection plate 92 is attached to the angle adjustment mechanism, and the reflection plate 92 is
Can be adjusted. For example, when the size of the transfer paper 40 conveyed by the conveyance belt 33 of the conveyance mechanism 30 is small, the fixing device makes the inclination angle of the reflection plate 92 relatively small by an angle adjustment mechanism as shown in FIG. The transfer paper 40 is heated by appropriately reflecting the infrared light radiated to the reflection plate 92 from the large non-sheet passing portion to the entire back surface of the transfer paper 40. When the size of the transfer paper 40 conveyed by the conveyance belt 33 is large, the fixing device increases the inclination angle of the reflection plate 92 by an angle adjusting mechanism, as shown in FIG. The transfer sheet 40 is heated by appropriately reflecting the infrared rays emitted from the paper portion to the reflection plate 92 on the entire back surface of the transfer sheet 40.

Therefore, the fixing device, in particular, the infrared irradiating section 90 has a simple configuration, and the inclination angle of the reflection plate 92 is adjusted in accordance with the size of the transfer paper 40, so that the fixing device is suitable regardless of the size of the transfer paper 40. In addition, the transfer paper 40 can be heated by reflecting infrared rays to the back surface of the transfer paper 40.

Further, in the fixing device according to the present embodiment, when the transfer paper 40 of a small size is passed, a large amount of infrared rays are radiated from the relatively large non-sheet passing portion to the back surface of the transfer paper 40 by the reflection plate 92. Transfer paper 40
The temperature of the small-sized transfer paper 40 and the unfixed toner 50 can be increased as compared with the case where the paper is passed.
Therefore, when the transfer paper 40 of a small size is passed, the set temperature in the subsequent heat roller type fixing unit 10 may be set to a lower temperature than when the transfer paper 40 of a large size is passed. it can.

That is, the fixing device of the present embodiment can set the set temperature of the heat roller type fixing section 10 to a necessary minimum according to the size of the transfer paper 40 to be passed, and can save extra energy. It is possible to save energy and further reduce energy consumption. In addition, the small-size transfer paper 40
If the temperature of the unfixed toner 50 becomes too high, a high-temperature offset may occur in the heat roller fixing unit 10, but by setting the heat roller fixing unit 10 to a low temperature,
Excessive heat can be removed, and hot offset can be prevented.

Further, the infrared lamp or the small-capacity heat source of the infrared irradiation section 90 has a fast rising speed, does not require preheating, can further reduce power consumption, and has a heating roller of the heating roller type fixing section 10. Since the heating temperature of the fixing device 11 can be reduced, the rising temperature can be further increased, the waiting time can be further reduced, and the usability of the fixing device can be improved.

[0107]

<Example 1> Ordinary plain paper copying machine, for example,
Spirio 7000 (trade name); an unfixed toner image is formed on the transfer paper by removing the fixing device manufactured by Ricoh Company, and the unfixed toner image is formed on the transfer paper by using the fixing device 1 of the first embodiment. An experiment was carried out to fix it to

However, in the fixing device 1, the conveyor belt 33 was formed of a polyimide film, and a halogen lamp was used as the infrared lamp 21 of the infrared irradiation section 20, and two aluminum parabolic mirrors were used as the infrared reflection mirror 22. In the fixing device 1, the heating roller 11 has a thickness of 1 m.
A silicon rubber layer and a tetrafluoroethylene layer were provided on an aluminum tube having a length of m, and a halogen heater was provided therein. Further, the fixing device 1 sets the fixing speed, that is, the transfer speed of the transfer paper to A4.
Forty sheets (40 cpm) per minute were passed in the horizontal direction, and the transfer paper was passed on the basis of the center.

In the fixing device 1 under the above conditions, a continuous 20 sheets of A4 horizontal paper are passed, and a continuous 2 sheets of A4 vertical paper are passed.
After passing zero sheets, ten sheets were continuously passed through A4 horizontal sheet passing to perform a fixing process.

As a result of the above experiment, the temperature rise phenomenon of the non-sheet passing portion of the transfer sheet of the heating roller 11 of the heat roller type fixing unit 10 did not occur at the time of the above-mentioned A-sheet passing, and the A4 No fixing failure such as offset occurred at the time of A4 horizontal paper passing, and a good fixed image could be obtained.

<Comparative Example 1> In order to conduct a comparative experiment, the infrared lamp 21 of the infrared irradiating section 20 of the fixing device 1 of Example 1 was removed, and the set temperature of the heating roller 11 of the heat roller type fixing section 10 was set to 180. With the temperature set to ° C., the same fixing operation as in Example 1 was performed.

As a result of the comparison experiment, in the A4 horizontal continuous paper feeding after the continuous A4 vertical paper feeding was performed for 20 sheets, the hot offset at both ends was caused by the temperature rise of the non-paper passing portion of the transfer paper of the heating roller 11. Occurred.

From the results of Example 1 and Comparative Example 1, it can be seen that arranging the infrared irradiating section 20 in front of the heat roller fixing section 10 and performing preheating suppresses the temperature rise in the non-paper passing section. It was found to be effective in preventing hot offset and improving fixing performance.

<Embodiment 2> A fixing device 1 similar to the fixing device 1 of the above-described embodiment 1 is used, except that a heating roller 11 is provided with a silicon rubber layer and a tetrafluoroethylene layer on a 0.5 mm-thick iron tube. Then, a current was supplied to the internal coil, and the heating roller 11 was heated by electromagnetic induction.

Using the fixing device 1 having the above-described structure, as in the first embodiment, after continuously passing 20 sheets of A4 paper horizontally and continuously passing 20 sheets of A4 vertical paper. , A
A fixing process was performed by continuously passing ten sheets through four horizontal sheets.

As a result of the experiment, at the time of the A-length paper passing, the temperature rise phenomenon of the non-sheet-passing portion of the transfer paper of the heating roller 11 of the heat roller type fixing unit 10 did not occur, and the A4 lengthwise passing paper did not occur. Even during A4 cross-feeding, a fixing failure such as offset did not occur, and a good fixed image could be obtained.

<Comparative Example 2> In order to perform a comparative experiment, the infrared lamp 21 of the infrared irradiation section 20 of the fixing device 1 of Example 2 was removed, and the set temperature of the heating roller 11 of the heat roller type fixing section 10 was set to 180. With the temperature set to ° C., the same fixing operation as in Example 2 was performed.

As a result of the comparative experiment, in the A4 horizontal continuous paper feeding after the continuous A4 vertical paper feeding was performed for 20 sheets, the hot offset was caused at both side edges due to the temperature rise of the non-paper passing portion of the transfer paper of the heating roller 11. Occurred.

In order to prevent this hot offset, it is necessary to provide a plurality of coil winding layers and to control the energization for each size of the transfer paper, which complicates the structure of the heating roller 11 and the energization control to the coil. I needed to.

<Embodiment 3> An ordinary plain paper copying machine, for example, Spiri7000 (trade name); a fixing device manufactured by Ricoh Co., Ltd. was removed, and an unfixed toner image was formed on transfer paper. An experiment was conducted in which an unfixed toner image was fixed on transfer paper using the fixing device 60 of the present embodiment.

However, the fixing device 60 is connected to the transport belt 33.
Was formed from a polyimide film, a xenon lamp (flash lamp) was used as the infrared lamp 21 of the infrared irradiation section 20, and two aluminum plates were used as the infrared reflection mirror 22. The fixing device 60 includes a fixing film 71.
As the heating element 72, a ceramic low heat capacity heater was used as the heating element 72, and the set temperature of the surface of the fixing film 71 was adjusted to 12
0 ° C. Further, the fixing device 60 sets the fixing speed, that is, the transfer speed of the transfer paper to 40 sheets per minute (40 cpm) in the A4 horizontal direction, and passes the transfer paper on the basis of the center.

In the fixing device 60 under the above conditions, a continuous 200 sheets of A4 paper were passed, and the fixing process was performed.

As a result of the above experiment, the temperature rise of the non-sheet passing portion of the transfer sheet of the fixing film 71 of the film type fixing section 70 did not occur during the above-mentioned vertical sheet passing, and the running property of the fixing film 71 was not improved. A stable and good fixed image could be obtained.

<Comparative Example 3> In order to conduct a comparative experiment, the flash lamp which is the infrared lamp 21 of the infrared irradiating section 20 of the fixing device 60 of Example 3 was removed, and the fixing film 71 of the film type fixing section 70 was set. 170 ° C
The same fixing operation as in the third embodiment was performed.

As a result of the comparative experiment, it was found that A4 vertical
When the sheet was fed, the fixing film 71 was slightly extended at both side edges from the central portion due to the temperature rise in the non-sheet passing portion of the transfer paper, and the running stability was deteriorated and wrinkles were generated.

From the results of Example 3 and Comparative Example 3, it can be seen that the provision of the infrared irradiation section 20 in front of the film-type fixing section 70 and the preliminary heating suppresses the temperature rise of the non-paper passing section. It has been found that it is effective in securing running stability to prevent wrinkles and improving fixing performance.

<Embodiment 4> A fixing device 1 similar to the fixing device 1 of the above-described embodiment 1 was used, and one aluminum plate was used as the infrared reflection mirror 22 using the transfer paper as one side reference.

Under the same conditions as in the first embodiment, continuous 20 sheets of paper are passed by A4 horizontal paper passing, 20 sheets of continuous A4 vertical paper passing are performed, and then continuous by A4 horizontal paper passing. 10
The sheet was passed, and a fixing process was performed.

As a result of the above experiment, the temperature rise phenomenon of the non-sheet-passing portion of the transfer paper of the heating roller 11 of the heat roller fixing unit 10 did not occur during the above-mentioned A-longitudinal sheet passing. No fixing failure such as offset occurred at the time of A4 horizontal paper passing, and a good fixed image could be obtained.

<Embodiment 5> A fixing device 1 similar to the above-described fixing device 1 of Embodiment 1 was used, and one sheet of aluminum plate was used as the infrared reflection mirror 22 with the transfer paper passing on one side as a reference. Further, similarly to the fourth embodiment, the infrared reflecting mirror 22 is attached to an angle adjusting mechanism so that the angle of the infrared reflecting mirror 22 can be adjusted according to the size of the transfer paper, particularly, the size in the width direction. did.

Under the same conditions as in the first embodiment, while the infrared reflection mirror 22 is adjusted by the angle adjusting mechanism in accordance with the width direction size of the transfer paper, 20 sheets of A4 lengthwise paper are continuously passed. After a continuous 20 sheets were passed through the A4 horizontal sheet passing, a continuous 20 sheets were passed through the B5 horizontal sheet passing to perform the fixing process.

As a result of the above experiment, the reflected light of the infrared light by the infrared reflecting mirror 22 on the back surface of the transfer paper can be made uniform in the plane even in the case of the longitudinal paper A and the transverse paper B5. Also in the transfer paper size, a good fixed image could be obtained.

<Embodiment 6> Using the same fixing device 1 as the fixing device 1 of the fifth embodiment, under the same conditions as those of the fifth embodiment, a continuous 20 sheets of A4 paper are continuously passed. A4
After a continuous 20 sheets were passed by the horizontal passing, a continuous 20 sheets were passed by the B5 horizontal passing to perform the fixing process.

However, the set temperature of the heat roller 11 of the heat roller type fixing unit 10 is set to 120 ° C. when the A4 paper is passed horizontally,
The temperature was adjusted to 110 ° C. for the longitudinal paper feeding and to 115 ° C. for the B5 longitudinal paper feeding for each transfer paper size.

As a result of the above experiment, a good fixed image could be obtained at the time of passing of any transfer paper size.

<Comparative Example 4> Using the same fixing device 1 as the fixing device 1 in the fifth embodiment, under the same conditions as in the fifth embodiment, a continuous 20 sheets of A4 paper were continuously passed. A4
After a continuous 20 sheets were passed by the horizontal passing, a continuous 20 sheets were passed by the B5 horizontal passing to perform the fixing process.

However, the set temperature of the heat roller 11 of the heat roller fixing unit 10 is set to 12 for all the transfer paper sizes.
The temperature was adjusted to 0 ° C.

As a result of the above experiment, a good fixed image could be obtained at the time of passing of any transfer paper size, but the energy consumption increased compared to the energy consumption in the sixth embodiment. .

Further, for all transfer paper sizes, the set temperature of the heating roller 11 was set to 110 ° C., and the same fixing process was performed.

As a result of the above experiment, in the fixing process for A4 landscape paper, the fixing property deteriorated due to insufficient heating of the heating roller 11.

As described above, the invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to the above, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

[0142]

According to the fixing device of the present invention, the recording material and the unfixed image forming material are brought into a non-contact state by irradiating a predetermined electromagnetic wave before the heating and pressing type fixing unit. A non-contact heating unit for heating to a predetermined temperature is provided, and a conveyance belt for conveying the recording material is formed of a member that transmits electromagnetic waves, and is irradiated from the non-contact heating unit before being conveyed to the heating and pressing type fixing unit. The recording material and the image forming material conveyed to the heating / pressing type fixing unit are preheated by irradiating the recording material with the electromagnetic wave to be irradiated on the front surface of the recording material and also irradiating the back surface of the recording material with reflection by the reflection member. Therefore, the rising speed of the fixing device can be increased, the temperature of the non-sheet passing portion of the transfer paper in the heating and pressing type fixing unit can be reduced, and the stability at high speed operation can be improved. And improved fixing performance It is possible to provide an inexpensive fixing device capable of Rukoto.

According to the fixing device of the second aspect of the present invention,
The heating / pressing type fixing unit includes a heating roller that is heated to a predetermined temperature, and a pressure roller that comes into contact with the heating roller at a predetermined pressure, and at least one of the heating roller and the pressure roller is rotationally driven to perform the heating. Since the roller-type fixing unit that fixes the image forming material by heating and pressing while conveying the recording material conveyed by the conveying mechanism between the roller and the pressing roller is used, a stable roller-type fixing unit is used. It can start up quickly and can support high-speed operation, can reduce the temperature rise of the non-sheet passing portion of the transfer paper of the heating roller, can improve stability at high-speed operation, and fix An inexpensive fixing device capable of improving performance can be provided.

According to the fixing device of the third aspect of the present invention,
Since the heating roller is heated by electromagnetic induction heating, it does not complicate the structure of the heating roller for electromagnetic induction heating with a good rising speed and raises the non-sheet passing portion of the transfer paper of the heating roller. The temperature can be reduced, the stability at high speed operation can be further improved, and the fixing performance can be improved.

According to the fixing device of the fourth aspect of the present invention,
The heating / pressing-type fixing unit includes a heating film heated to a predetermined temperature, and a pressing roller that comes into contact with the heating film at a predetermined pressure, and the pressing roller is driven to rotate so that the heating film and the pressing roller Since a film-type fixing unit that fixes the image forming substance by heating and pressing while conveying the recording material conveyed by the conveyance mechanism during the
It is possible to reduce the temperature rise of the non-sheet passing area of the transfer paper of the film type fixing unit with low heat capacity, to further increase the startup speed while further reducing energy consumption, and to improve the fixing performance. An inexpensive fixing device that can be provided can be provided.

According to the fixing device of the fifth aspect,
Since a non-contact heating unit that irradiates infrared rays as electromagnetic waves is used, the image forming substance and the recording material can be heated more efficiently, and the stability at high speed operation can be further improved. In addition, the fixing performance can be improved.

According to the fixing device of the sixth aspect,
As the non-contact heating means, which emits electromagnetic waves by a flash lamp, the burning of the recording material can be further reduced, and the stability can be further improved.

According to the fixing device of the seventh aspect,
The transport mechanism transports the recording material in a direction orthogonal to the transport direction of the recording material by the transport belt, with the recording material approaching to one side. The recording material is conveyed on a so-called one-side basis, and the reflection member is provided only on the non-sheet passing portion side of the recording material. The arrangement can be further simplified, and the configuration can be further simplified and the cost can be further reduced.

According to the fixing device of the eighth aspect,
As the non-contact heating means, an angle adjusting mechanism for adjusting the inclination angle of the reflecting member according to the size of the recording material is provided, so that the electromagnetic wave incident on the reflecting member can be appropriately applied regardless of the size of the recording material. Thus, the light can be reflected in the direction of the recording material, and the energy consumption can be further reduced.

According to the fixing device of the ninth aspect,
As a heating and pressing type fixing unit, depending on the size of the recording material,
Since the apparatus having the temperature control unit for adjusting the heating temperature is used, the heat and pressure fixing unit can apply appropriate heat to the recording material and the image forming material regardless of the size of the recording material. Thus, the fixing performance can be further improved, and the energy consumption can be further reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a fixing device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of an infrared irradiation unit of the fixing device of FIG.

FIG. 3 is a front view of a fixing device according to a second embodiment of the present invention;

FIG. 4 is an enlarged side view of an infrared irradiation unit of a fixing device to which a third embodiment of the fixing device according to the invention is applied.

FIG. 5 is an enlarged side view of a fixing device to which a fourth embodiment of the fixing device of the present invention is applied when a small-sized transfer sheet of an infrared irradiation unit is passed.

FIG. 6 is an enlarged side view of a case where a large-size transfer sheet of the infrared irradiation unit in FIG. 5 is passed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixing apparatus 10 Heat roller type fixing part 11 Heating roller 12 Pressure roller 13 Heat source 20 Infrared irradiation part 21 Infrared lamp 22 Infrared reflecting mirror 23 Reflector 30 Transport mechanism 31, 32 Transport roller 33 Transparent transport belt 40 Transfer paper 50 Toner ( Unfixed toner) 60 Fixing device 70 Film fixing unit 71 Fixing film 72 Heating unit 73 Pressure roller 80, 90 Infrared irradiation unit 81, 91 Infrared reflecting mirror 82, 92 Reflecting plate

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H05B 3/10 H05B 3/10 B 6/14 6/14

Claims (9)

[Claims] A fixing device for heating and pressurizing a recording material to which an unfixed image-forming substance is attached while fixing the image-forming substance to the recording material while conveying the recording material; A conveyance mechanism for conveying the recording material to the heating and pressing type fixing unit, and a predetermined electromagnetic wave radiated from an electromagnetic wave irradiating means to the recording material conveyed to the heating and pressing type fixing unit by the conveyance mechanism. A non-contact heating means for heating the recording material and the unfixed image forming substance to a predetermined temperature in a non-contact state, wherein the transport mechanism places the recording material on the heating and pressurizing type fixing unit. Transported to
The non-contact heating unit further includes a transport belt that transmits the electromagnetic wave irradiated by the non-contact heating unit, the non-contact heating unit is disposed at a position opposite to the electromagnetic wave irradiation unit with the conveyance belt interposed therebetween, and A fixing device, comprising: a reflecting member that reflects the electromagnetic waves that have been irradiated and transmitted through a portion of the transport belt that does not pass through the recording material in a direction toward the recording material that is transported by the transport belt. 2. The heating / pressing type fixing section includes a heating roller heated to a predetermined temperature, and a pressure roller contacting the heating roller with a predetermined pressure, and at least one of the heating roller and the pressure roller. One is a roller-type fixing unit that rotates and drives to heat and pressurize while fixing the image forming material while conveying the recording material conveyed by the conveyance mechanism between the heating roller and the pressure roller. The fixing device according to claim 1, wherein: 3. The fixing device according to claim 2, wherein the heating roller is heated by electromagnetic induction heating. 4. The heating / pressing type fixing section includes a heating film heated to a predetermined temperature, and a pressure roller abutting on the heating film at a predetermined pressure, and the pressure roller is driven to rotate by the rotation. A film fixing unit for fixing the image forming material by heating and pressing the recording material conveyed by the conveyance mechanism between the heating film and the pressure roller while conveying the recording material. 2. The fixing device according to claim 1. 5. The fixing device according to claim 1, wherein said non-contact heating means irradiates infrared rays as said electromagnetic waves. 6. The non-contact heating means irradiates the electromagnetic wave with a flash lamp.
The fixing device according to any one of claims 1 to 4. 7. A transport mechanism according to claim 1, wherein said transport mechanism is configured to:
The recording material is conveyed in a state of being shifted to one side, and the reflection member of the non-contact heating means is disposed at an end position of the transport belt opposite to the side on which the recording material is shifted. The fixing device according to any one of claims 1 to 6, wherein the fixing device is used. 8. The apparatus according to claim 1, wherein said non-contact heating means includes an angle adjusting mechanism for adjusting an inclination angle of said reflection member according to a size of said recording material. The fixing device according to any one of the above. 9. The fixing device according to claim 1, wherein the heating and pressing type fixing unit includes a temperature adjusting unit for adjusting the heating temperature according to the size of the recording material. A fixing device according to any one of the above.