JP3804470B2 - Fixing apparatus and image forming apparatus using the same - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention employs an image forming system such as an electrophotographic system, an electrostatic recording system, an ionography, a magnetic recording system, etc., and is used in an image forming apparatus such as a copying machine, a printer, or a facsimile machine that forms a color or black and white image BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device and an image forming apparatus using the fixing device. It relates to the device.
[0002]
[Prior art]
Conventional image forming apparatuses such as copiers, printers, and facsimiles that employ image forming methods such as the above-described electrophotographic methods are not limited to image quality requirements such as full color and high image quality, and are small in size. It has been required to meet various demands such as shortening the service life, extending the service life, increasing productivity, reducing power consumption, and shortening the first printout time (the time until the first sheet can be printed after the power is turned on). ing.
[0003]
The present applicant has proposed various image forming apparatuses in order to meet the needs required for such image forming apparatuses such as copying machines and printers. For example, as disclosed in Japanese Patent Application Laid-Open No. 10-78686. An image forming apparatus capable of downsizing the apparatus and capable of forming a high-quality color image without using a complicated image misregistration technique has already been proposed.
[0004]
The image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 10-78686 includes various embodiments. As one of the embodiments, a unit composed of two photosensitive members and one intermediate transfer member. A unit structure composed of a structure, two other photoconductors, and one intermediate transfer member is provided, and the two intermediate transfer members are configured to be in contact with another intermediate transfer member. Proposed. The four photoconductors shown here have a common tangent line. Therefore, the charging device, the exposure device, the developing device, and the cleaning device arranged around these four photoconductors have their respective photoconductors. Can be arranged at the same position, and the devices are made common for each device type.
[0005]
In the case of this image forming apparatus, the toner images of the respective colors formed on the two photoconductors are transferred to the intermediate transfer member, then transferred to the final intermediate transfer member, and formed on the other two photoconductors. Each toner image is transferred to the other intermediate transfer member and then transferred to the final intermediate transfer member. The toner images transferred to the final intermediate transfer member are collectively transferred onto the conveyed recording paper. . The toner image transferred onto the paper is fixed on the recording paper by the fixing device. Since the intermediate transfer member is a drum type and is formed of a rigid body, the positional deviation between the toner images hardly occurs.
[0006]
By the way, the fixing device used in this type of so-called tandem type image forming apparatus has reduced power consumption and shortened the first printout time (the time until the first sheet can be printed). It is required to satisfy the requirements.
[0007]
As a fixing device that meets such requirements, a heating roll having a heating source therein, a fixing belt formed in an endless belt shape, a belt guide member that rotatably supports both ends of the fixing belt, and the fixing belt And a pressing member that presses the fixing belt against the surface of the heating roll, and a recording medium carrying an unfixed toner image in a nip formed between the heating roll and the fixing belt. Some are configured to perform fixing processing by heat and pressure by passing through.
[0008]
In this fixing device, the pressure member is not a roll-shaped member, but a pressure belt is configured by pressing a fixing belt formed in an endless belt shape to a heating roll by the pressure contact member. The heat capacity of the member can be reduced, and the heating roll can be made thin, and the power for heating the heating roll to a predetermined fixing temperature can be reduced and the time can be shortened. It is possible to reduce the first printout time (the time from when the power is turned on until the first sheet can be printed).
[0009]
[Problems to be solved by the invention]
However, the conventional technique has the following problems. That is, in the case of a fixing device used in the conventional image forming apparatus, a heating roll having a heating source therein, a fixing belt formed in an endless belt shape, and both end portions of the fixing belt are rotatable. A belt guide member to be supported; and a pressure contact member that is disposed inside the fixing belt and presses the fixing belt against the surface of the heating roll; and a nip portion formed between the heating roll and the fixing belt, By passing a recording medium carrying an unfixed toner image, fixing processing is performed by heat and pressure. Therefore, in the case of the above fixing device, the heat capacity of the pressure member composed of the heating roll, the fixing belt, and the pressure contact member is significantly smaller than that of the conventional fixing device, thereby reducing power consumption and shortening the first printout time. Although it is possible, if the power supply voltage of the device fluctuates, the effect immediately appears as a change in the amount of heat generated by a heating source such as a halogen lamp that heats the heating roll, the fusing temperature fluctuates, and fusing failure or However, there is a problem that high temperature offset or low temperature offset occurs. Such a problem may occur in an office or the like when an OA device such as a personal computer is fully operated, or when the image forming apparatus is used overseas where power supply conditions are poor. There is.
[0010]
Therefore, the present invention has been made to solve the above-described problems of the prior art, and the object of the present invention is to always provide an image with good image quality even when the power supply voltage of the apparatus fluctuates from a specified value. It is an object of the present invention to provide a fixing device capable of being formed and an image forming apparatus using the same.
[0011]
[Means for Solving the Problems]
  In order to solve the above problems, the invention described in claim 1
The pressure member is pressed against the heating member,
The heating member andSaidFixing device for fixing by passing a recording medium carrying an unfixed toner image through a nip formed between pressure membersBecause,
Detecting the temperature rise rate of the heating member,
From the detected temperature rise ratePower supply voltage value input to the apparatus body where the fixing device is usedDetect
The detected power supply voltage valueIn the fixing device that changes the fixing parameter according to
Comprising storage means for storing the detected temperature rise rate;
When the temperature of the heating member is equal to or higher than a predetermined temperature when the apparatus main body is turned on, the temperature increase rate stored in the storage means is used.It is.
[0012]
Here, the “fixing parameters” include all parameters for the fixing device to perform the fixing process. One or more of the parameters can be selectively used as appropriate.
[0013]
Further, in the invention described in claim 2, the fixing parameter of the fixing device is at least one of a set temperature, the number of fixings per unit time, the number of fixings that can be processed continuously, and a fixing limit. The fixing device according to claim 1. Here, the fixing limitation means a case where the fixing operation is forcibly prohibited for a certain time, for example, when fixing processing is performed for each of a large number.
[0015]
Furthermore,Claim 3The invention described in the above item is characterized in that the rate of temperature rise of the heating member is detected by the time during which the temperature of the heating member changes in a predetermined temperature section.Claim 1The fixing device according to (1).
[0018]
Furthermore,Claim 4The invention described in the above item is characterized in that the fixing parameter of the fixing device is changed according to the installation environment of the apparatus main body in which the fixing device is used.Claims 1 to 3The fixing device according to any one of the above.
[0019]
Also,Claim 5In the invention described in the above, after transferring toner images of different colors formed on a plurality of image carriers onto a recording medium via one or a plurality of intermediate transfer members, heating having a heating source therein is performed. The heating roll and the fixing unit are provided with a fixing device including a roll, a fixing belt formed in an endless belt shape, and a pressure contact member disposed inside the fixing belt and press-contacting the fixing belt to the surface of the heating roll. Image forming apparatus for forming an image by passing a recording medium carrying an unfixed toner image through a nip formed between belts and fixing the recording mediumBecause,
Detecting the temperature rise rate of the heating member,
From the detected temperature rise ratePower supply voltage value input to the apparatus body where the fixing device is usedDetect
The detected power supply voltage valueIn the fixing device that changes the fixing parameter according to
Comprising storage means for storing the detected temperature rise rate;
When the temperature of the heating member is equal to or higher than a predetermined temperature when the apparatus main body is turned on, the temperature increase rate stored in the storage means is used.An image forming apparatus characterized by the above.
[0020]
As the plurality of image carriers, for example, those that form toner images of each color of cyan (C), magenta (M), yellow (Y), and black (K) are used. Of course, other types may be used.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0022]
FIG. 2 shows a tandem type full-color printer as an image forming apparatus according to Embodiment 1 of the present invention.
[0023]
In FIG. 2, reference numeral 01 denotes a main body of a tandem type full-color printer. The printer main body 01 is roughly divided into a print head device (Print Head Device) 02 for forming a full-color image and this print. ROS (Raster Output Scanner) 03 as an exposure device that performs image exposure on the four photosensitive drums 11, 12, 13, and 14 as the image carrier of the head device 02, and the developing device 41 for each color of the print head device 02 , 42, 43, 44, four toner boxes 04Y, 04M, 04C, 04K for supplying toner corresponding to colors, and a paper feed cassette 05 for supplying recording paper P as a recording medium to the print head device 02, A fixing device 70 for performing a fixing process on the recording paper P onto which the toner image is transferred from the print head device 02, and the recording paper P on which an image is fixed on one side by the fixing device 70 , With both sides reversed, a double-sided conveyance path 07 for conveying again to the transfer section of the print head device 02, and a manual sheet feeding means 08 for feeding a desired recording sheet P from the outside of the printer main body 01, A controller 09 that controls the operation of the printer and an electric circuit 10 that includes an image processing circuit that performs image processing on an image signal, a high-voltage power supply circuit, and the like are provided. In FIG. 2, T indicates a discharge toilet for discharging the recording paper P on which an image is formed. The discharge toilet T is integrally disposed on the upper portion of the printer main body 01.
[0024]
Among the various members arranged in the printer main body 01, ROS03 as an exposure device is image data corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K). From four semiconductor lasers that are driven to light based on the above, four laser beams emitted from these four semiconductor lasers, f-θ lenses for deflecting scanning, polygon mirrors, or a plurality of reflection mirrors It is configured.
[0025]
FIG. 3 shows a print head device of a tandem type full-color printer as an image forming apparatus according to Embodiment 1 of the present invention. In addition, the arrow in FIG. 3 has shown the rotation direction of each rotation member.
[0026]
As shown in FIG. 3, the print head device 02 includes photosensitive drums (image carriers) 11, 12, 13, for yellow (Y), magenta (M), cyan (C), and black (K). Image forming units 1, 2, 3, 4 having 14, and charging rolls (contact type charging devices) 21, 22, 23, 24 for primary charging that contact these photosensitive drums 11, 12, 13, 14, ROS (exposure device) 03 (see FIG. 2) for irradiating laser beams 31, 32, 33, and 34 of yellow (Y), magenta (M), cyan (C), and black (K) colors, and the above-described photoconductor Developing devices 41, 42 for developing the electrostatic latent images formed on the drums 11, 12, 13, 14 with yellow (Y), magenta (M), cyan (C), and black (K) toners. , 43, 44 and a first primary intermediate transfer drum (intermediate transfer drum) that contacts two of the four photosensitive drums 11, 12, 13, 14 Body) 51 and the second primary intermediate transfer drum (intermediate transfer body) 52 in contact with the other two photosensitive drums 13 and 14, and the second primary intermediate transfer drum 51 and 52 in contact with the first and second primary intermediate transfer drums 51 and 52. A main portion is constituted by a secondary intermediate transfer drum (intermediate transfer member) 53 and a final transfer roll (transfer member) 60 that contacts the secondary intermediate transfer drum 53.
[0027]
The photosensitive drums 11, 12, 13, and 14 are arranged at a constant interval so as to have a common tangential plane M.sub.2. Further, the first primary intermediate transfer drum 51 and the second primary intermediate transfer drum 52 are surfaces whose rotational axes are parallel to the photosensitive drums 11, 12, 13, and 14 and have predetermined symmetry planes as boundaries. They are arranged in a symmetrical relationship. Further, the secondary intermediate transfer drum 53 is arranged so that the rotation axis thereof is parallel to the photosensitive drums 11, 12, 13, and 14.
[0028]
A signal corresponding to the image information for each color is rasterized by an image processing circuit disposed in the electric circuit 10 (see FIG. 2) and input to the ROS03. In this ROS03, the laser beams 31, 32, 33, and 34 of yellow (Y), magenta (M), cyan (C), and black (K) are modulated, and the corresponding photosensitive drums 11, 12, and 12 are modulated. 13 and 14 are irradiated.
[0029]
Around each of the photosensitive drums 11, 12, 13, and 14, an image forming process for each color is performed by a known electrophotographic method. First, as the photoconductor drums 11, 12, 13, and 14, for example, photoconductor drums using an OPC photoconductor having a diameter of 20 mm are used. These photoconductor drums 11, 12, 13, and 14 are, for example, It is rotationally driven at a rotational speed of 95 mm / sec. As shown in FIG. 3, the surfaces of the photosensitive drums 11, 12, 13, and 14 are applied with a DC voltage of about -840V to charging rolls 21, 22, 23, and 24 as contact-type charging devices. For example, it is charged to about -300V. The contact-type charging device includes a roll type, a film type, a brush type, and the like, but any type may be used. In this embodiment, a charging roll generally used in an electrophotographic apparatus in recent years is employed. Further, in order to charge the surfaces of the photosensitive drums 11, 12, 13, and 14, in this embodiment, a charging method in which only DC is applied is used, but a charging method in which AC + DC is applied may be used.
[0030]
Thereafter, laser light 31 corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K) is applied to the surfaces of the photosensitive drums 11, 12, 13, and 14 by ROS03 as an exposure device. , 32, 33, and 34 are irradiated, and an electrostatic latent image corresponding to input image information for each color is formed. When the electrostatic latent image is written by ROS03, the photosensitive drums 11, 12, 13, and 14 are discharged to a surface potential of the image exposure portion of about −60 V or less.
[0031]
In addition, electrostatic latent images corresponding to yellow (Y), magenta (M), cyan (C), and black (K) colors formed on the surfaces of the photosensitive drums 11, 12, 13, and 14 Are developed by the developing devices 41, 42, 43, and 44 of the colors to be processed, and yellow (Y), magenta (M), cyan (C), and black (K) colors on the photosensitive drums 11, 12, 13, and 14, respectively. Visualized as a toner image.
[0032]
In this embodiment, as the developing devices 41, 42, 43, 44, a magnetic brush contact type two-component developing method is adopted, but the scope of application of the present invention is not limited to this developing method, Needless to say, the present invention can be sufficiently applied to a non-contact type developing system.
[0033]
The developing devices 41, 42, 43, and 44 are filled with yellow (Y), magenta (M), cyan (C), and black (K) toners of different colors and a developer composed of a carrier. Yes. As shown in FIG. 2, when toner is supplied from the corresponding color toner boxes 04Y, 04M, 04C, and 04K, the supplied toner is supplied to the developing devices 41, 42, 43, and 44. At 404, the carrier is sufficiently agitated and triboelectrically charged. Inside the developing roll 401, a magnet roll (not shown) having a plurality of magnetic poles arranged at a predetermined angle is fixed. By the paddle 403 that conveys the developer to the developing roll 401, the amount of the developer conveyed to the vicinity of the surface of the developing roll 401 is regulated by the developer amount regulating member 402. In this embodiment, the amount of the developer is 30 to 50 g / m.²Further, the charge amount of the toner existing on the developing roll 401 at this time is about -20 to 35 μC / g.
[0034]
The toner supplied onto the developing roll 401 is in the form of a magnetic brush composed of a carrier and toner by the magnetic force of the magnet roll, and this magnetic brush comes into contact with the photosensitive drums 11, 12, 13, and 14. ing. A developing bias voltage of AC + DC is applied to the developing roll 401 to develop the toner on the developing roll 401 into an electrostatic latent image formed on the photosensitive drums 11, 12, 13, and 14. It is formed. In this embodiment, for example, the AC component of the developing bias voltage is set to 4 kHz, 1.5 kVpp, and the DC component is set to about -230V.
[0035]
In this embodiment, in the developing devices 41, 42, 43, and 44, so-called “spherical toner” that is a substantially spherical toner is used, and an average particle diameter of about 3 to 10 μm is used. For example, the average particle diameter of the black toner is set to 8 μm, and the average particle diameter of the color toner is set to 7 μm.
[0036]
Next, the yellow (Y), magenta (M), cyan (C), and black (K) toner images formed on the photosensitive drums 11, 12, 13, and 14 are the first primary images. The secondary transfer is electrostatically performed on the intermediate transfer drum 51 and the second primary intermediate transfer drum 52. The yellow (Y) and magenta (M) color toner images formed on the photoconductive drums 11 and 12 are formed on the first primary intermediate transfer drum 51 and cyan (on the photoconductive drums 13 and 14). C) and black (K) toner images are transferred onto the second primary intermediate transfer drum 52, respectively. Therefore, on the first primary intermediate transfer drum 51, the single color image transferred from either the photosensitive drum 11 or 12 and the two color toner images transferred from both the photosensitive drums 11 and 12 are superimposed. A double color image is formed. In addition, similar single-color images and double-color images are also formed on the second primary intermediate transfer drum 52 from the photosensitive drums 13 and 14.
[0037]
The surface potential necessary for electrostatically transferring the toner image from the photosensitive drums 11, 12, 13, 14 onto the first and second primary intermediate transfer drums 51, 52 is about +250 to 500V. It is. This surface potential is set to an optimum value depending on the charged state of the toner, the ambient temperature, and the humidity. The ambient temperature and humidity can be easily known by detecting the resistance value of a member having a characteristic that the resistance value varies depending on the ambient temperature and humidity. As described above, when the charge amount of the toner is in the range of −20 to 35 μC / g and is in a normal temperature and humidity environment, the surface potential of the first and second primary intermediate transfer drums 51 and 52 is + 380V is desirable.
[0038]
The first and second primary intermediate transfer drums 51 and 52 used in this embodiment have an outer diameter of 42 mm, for example, and a resistance value of 10⁸It is set to about Ω. The first and second primary intermediate transfer drums 51 and 52 are cylindrical rotating bodies having a single layer or a plurality of layers whose surfaces are flexible or elastic, and are generally made of Fe, Al, or the like. A low resistance elastic rubber layer represented by conductive silicone rubber (R = 10) on a metal pipe as a metal core²~Ten^ThreeΩ) is provided in a thickness of about 0.1 to 10 mm. Furthermore, the outermost surfaces of the first and second intermediate transfer drums 51 and 52 are typically high release layers (R = 10) of fluororubber in which fluororesin fine particles are dispersed and having a thickness of 3 to 100 μm.^Five~Ten⁹Ω) and bonded with a silane coupling agent-based adhesive (primer). What is important here is the resistance value and the releasability of the surface, and the resistance value of the high release layer is R = 10.^Five~Ten⁹The material is not particularly limited as long as it is about Ω and has a high releasability.
[0039]
The single-color or double-color toner images formed on the first and second primary intermediate transfer drums 51 and 52 in this way are electrostatically and tertiary-transferred onto the secondary intermediate transfer drum 53. Therefore, a final toner image from a single color image to a quadruple color image of yellow (Y), magenta (M), cyan (C), and black (K) is formed on the secondary intermediate transfer drum 53. Will be.
[0040]
The surface potential necessary for electrostatically transferring the toner image from the first and second primary intermediate transfer drums 51 and 52 onto the secondary intermediate transfer drum 53 is about +600 to 1200V. This surface potential is the same as when the toner is transferred from the photosensitive drums 11, 12, 13, 14 to the first primary intermediate transfer drum 51 and the second primary intermediate transfer drum 52. Will be set to the optimum value. Further, since what is necessary for the transfer is a potential difference between the first and second primary intermediate transfer drums 51 and 52 and the secondary intermediate transfer drum 53, the first and second primary intermediate transfer drums 51 and 52 have different potentials. It is necessary to set the value according to the surface potential. As described above, the charge amount of the toner is in the range of −20 to 35 μC / g, and the surface potential of the first and second primary intermediate transfer drums 51 and 52 is +380 V in a normal temperature and humidity environment. The surface potential of the secondary intermediate transfer drum 53 is about +880 V, that is, the potential difference between the first and second primary intermediate transfer drums 51 and 52 and the secondary intermediate transfer drum 53 is + It is desirable to set it to about 500V.
[0041]
For example, the secondary intermediate transfer drum 53 used in this embodiment has an outer diameter of 42 mm, which is the same as the first and second primary intermediate transfer drums 51 and 52, and has a resistance value of 10 mm.¹¹It is set to about Ω. Similarly to the first and second primary intermediate transfer drums 51 and 52, the secondary intermediate transfer drum 53 is a cylindrical rotating body having a single layer or a plurality of layers whose surface is flexible or elastic. In general, a low resistance elastic rubber layer (R = 10) represented by conductive silicone rubber or the like on a metal pipe as a metal core made of Fe, Al or the like.²~Ten^ThreeΩ) is provided in a thickness of about 0.1 to 10 mm. Further, the outermost surface of the secondary intermediate transfer drum 53 is typically formed by forming a fluororubber in which fluororesin fine particles are dispersed as a high release layer having a thickness of 3 to 100 μm, and a silane coupling agent-based adhesive. (Primer). Here, the resistance value of the secondary intermediate transfer drum 53 needs to be set higher than that of the first and second primary intermediate transfer drums 51 and 52. Otherwise, the secondary intermediate transfer drum 53 will charge the first and second primary intermediate transfer drums 51, 52, making it difficult to control the surface potential of the first and second primary intermediate transfer drums 51, 52. Become. The material is not particularly limited as long as the material satisfies such conditions.
[0042]
Next, the final toner image from the single color image to the quadruple color image formed on the secondary intermediate transfer drum 53 is tertiary transferred onto the paper P passing through the paper conveyance path by the final transfer roll 60. . The paper P passes through a paper transporting roll 90 through a paper feeding process (not shown), and is fed into the nip portion between the secondary intermediate transfer drum 53 and the final transfer roll 60. After this final transfer step, the final toner image formed on the paper is fixed by the fixing device 70, and a series of image forming processes is completed.
[0043]
By the way, the fixing device according to this embodiment is disposed in a state in which a heating roll having a heating source therein, a fixing belt formed in an endless belt shape, and fitted inside the both ends of the fixing belt. A belt guide member that rotatably guides the inner surface of the fixing belt, a pressure contact member that is disposed inside the fixing belt and presses the fixing belt against the surface of the heating roll, and an oil on the inner surface of the fixing belt. An oil supply member for supplying the toner image, and fixing is performed by passing a recording medium carrying an unfixed toner image through a nip portion formed between the heating roll and the fixing belt.
[0044]
FIG. 4 is a perspective view showing the appearance of the fixing device according to this embodiment, and FIG. 5 is a cross-sectional view showing the fixing device according to this embodiment.
[0045]
As shown in FIG. 5, a fixing device 70 according to this embodiment is configured so that a heating roll 702 having a heating source 701 therein, an endless belt-like fixing belt 703, and the fixing belt 703 are rotatable. A belt guide member 704 that supports both ends of the fixing belt 703, a pressure contact member 705 that is disposed inside the fixing belt 703 and presses the fixing belt 703 against the surface of the heating roll 702, and an inner surface of the fixing belt 703 And a felt member 706 serving as an oil supply member for supplying oil. In FIG. 5, reference numeral 750 denotes an exit roll of the fixing device 70.
[0046]
The heating roll 702 includes a thin cylindrical cored bar made of iron or stainless steel, an elastic layer made of silicon rubber or the like coated on the surface of the cored bar, and a surface of the elastic layer. And a release layer having a thickness of about 30 μm, which is made of PFA or the like that is coated. In addition, a 600 W halogen lamp 701 is disposed inside the heating roll 702 as a heating source.
[0047]
The fixing belt 703 is formed of a synthetic resin such as polyimide in the form of an endless belt having an outer diameter of 30 mm and a thickness of 75 μm, and a release layer made of PFA or the like is provided on the surface as necessary. It is done.
[0048]
Further, as shown in FIG. 6, the belt guide member 704 is configured to be integrally assembled with the pressure contact member 705.
[0049]
As shown in FIGS. 6 and 7, the pressure contact member 705 includes a synthetic resin belt housing 707, and a metal belt frame 708 having a substantially U-shaped cross section that is fitted to the belt housing 707. The nip head member 709 for bringing the fixing belt 703 into pressure contact with the heating roll 702 and a pad member 710 attached to the nip head member 709 are mainly configured.
[0050]
Further, as shown in FIGS. 6 and 7, the belt guide member 704 is fitted to both end portions of the belt housing 707 in a state in which the belt guide member 704 is fitted to fitting portions 708a projecting parallel to each other at both end portions of the belt frame 708. It comes to be attached to the part.
[0051]
Further, the felt member 706 as the oil supply member is made of, for example, Nomex (trade name), and the felt member 706 is impregnated with about 2.0 g of oil made of amino Si oil having a viscosity of 300 cs. . As shown in FIGS. 5 and 7, the felt member 706 is attached to the back side of the belt frame 708 in a state of being fixed by means such as adhesion.
[0052]
Further, as shown in FIG. 8, the pressure contact member 705 is attached to an arm member 717 via a belt guide member 704, and the arm member 717 is heated by a coil spring 718 to press the pressure contact member 705 with a heating roll 702. Are configured to be brought into pressure contact with each other at a predetermined pressure. 7 and 8, reference numeral 719 denotes a synthetic resin film-like sheet member interposed between the fixing belt 703 and the pressure contact member 705. The friction between the two is reduced, but not necessarily provided.
[0053]
By the way, in this embodiment, the pressure member is brought into pressure contact with the heating member, and the recording medium carrying the unfixed toner image is passed through the nip portion formed between the heating member and the pressure member. In the fixing device that performs the fixing, the fixing parameter of the fixing device is changed in accordance with a power supply voltage value input to a main body of the device in which the fixing device is used.
[0054]
Further, in this embodiment, the fixing parameter of the fixing device is configured to be at least one of a set temperature, the number of fixings per unit time, the number of fixings that can be processed continuously, and a fixing limit. Yes.
[0055]
Furthermore, in this embodiment, the power supply voltage value input to the apparatus main body in which the fixing device is used is configured to be detected by the temperature increase rate of the heating member, and the temperature increase rate of the heating member is For example, it is detected by the time when the temperature of the heating member changes in a predetermined temperature section.
[0056]
In this embodiment, the temperature increase rate before the power is turned off is stored when the power of the apparatus main body in which the fixing device is used is turned on / off. In this case, when the temperature of the heating member is equal to or higher than a predetermined temperature, for example, the temperature increase rate stored before the power is turned off is used when the power of the apparatus main body in which the fixing device is used is turned on / off. Configured to do.
[0057]
Further, in this embodiment, the fixing parameter of the fixing device is changed according to the installation environment of the apparatus main body in which the fixing device is used.
[0058]
FIG. 1 is a block diagram showing a control circuit of a color printer as an image forming apparatus according to Embodiment 1 of the present invention.
[0059]
In FIG. 1, 100 is a CPU as a control means for controlling the image forming operation of the color printer, 101 is a ROM storing a program executed by the CPU 100, 102 is a RAM storing parameters of the program executed by the CPU 100, 103 is A control panel for inputting and setting information for executing an image forming operation such as the size and type (material) of a recording medium on which an image is formed by a color printer, an image forming mode of color or black and white, single-sided or double-sided, and the number of prints; 104 is a temperature sensor for detecting the temperature of the heating roll of the fixing device 70, 105 is an energization control means for controlling the energization of the halogen lamp of the fixing device 70, and 106 is a drive for driving the photosensitive drum or the fixing device of the color printer. A driving circuit for driving the motor, 107 is an image forming timing control means for controlling the image forming timing, and 108 is an image shape An image forming speed control means for controlling the speed in which respectively.
[0060]
In the above embodiment, the power supply voltage value input to the color printer using the fixing device is detected by the temperature increase rate of the heating roll, but the color printer using the fixing device is used. Alternatively, the power supply voltage value input to may be directly detected.
[0061]
In the above configuration, the fixing device used in the color printer according to this embodiment always forms an image with good image quality even when the power supply voltage of the device fluctuates from a specified value as follows. Is possible.
[0062]
That is, in the fixing device 70 used in the color printer according to this embodiment, as shown in FIG. 5, a heating roll 702 having a heating source 701 therein, a fixing belt 703 formed in an endless belt shape, A belt guide member 704 that supports both ends of the fixing belt 703 so that the fixing belt 703 can rotate, and a fixing belt 703 that is disposed inside the fixing belt 703 and presses the fixing belt 703 against the surface of the heating roll 702. A recording medium that includes a pressure contact member 705 and a felt member 706 that supplies oil to the inner surface of the fixing belt 703, and carries a non-fixed toner image in a nip formed between the heating roll 702 and the fixing belt 703. Fixing is done by passing P.
[0063]
By the way, in a color printer using the fixing device 70, when the power of the device is turned on, as shown in FIG. 9, the halogen lamp 701 for heating the heating roll 702 of the fixing device 70 is energized to Is heated to a predetermined standby temperature (for example, 150 ° C.).
[0064]
At this time, the power supply voltage input to the color printer is not necessarily equal to a specified value (for example, 100 V), and may differ from the specified value due to various factors. When the power supply voltage input to the color printer fluctuates, the temperature increase rate when the heating roll 702 is heated to a predetermined standby temperature (for example, 150 ° C.) changes.
[0065]
Therefore, in this embodiment, as shown in FIG. 10, the CPU 100 determines the power supply voltage input to the color printer according to the temperature increase rate when the heating roll 702 is heated to a predetermined standby temperature (for example, 150 ° C.). It comes to detect. That is, the CPU 100 detects the rate of temperature increase when the heating roll 702 is heated to a predetermined standby temperature based on the time during which the temperature of the heating roll 702 changes in a predetermined temperature section (for example, 50 ° C. to 100 ° C.). It has become.
[0066]
When the CPU 100 detects the rate of temperature increase when the heating roll 702 is heated to a predetermined standby temperature, the value is stored in the RAM 102. When the temperature of the heating roll 702 is equal to or higher than a predetermined temperature, for example, when the color printer using the fixing device 70 is turned on / off, the temperature increase rate stored before turning off the power is used. Is configured to do.
[0067]
In other words, if the temperature of the heating roll 702 when the color printer is turned on is equal to or higher than a predetermined temperature, the rate of temperature increase of the heating roll 702 may not change corresponding to the power supply voltage with high accuracy. Therefore, in this case, the temperature increase rate stored before the power is turned off is used.
[0068]
In addition, if the setting environment (for example, temperature) of the color printer changes more than normal, the setting temperature of the heating roll 702 differs, for example, at high temperature and high humidity. In this case, the fixing device The fixing parameters of the fixing device 70 may be changed according to the installation environment of the color printer in which the 70 is used.
[0069]
For example, when the power supply voltage input to the color printer is 100V, the temperature of the heating roll 702 changes as shown in FIG. 10A, but when the input power supply voltage is as high as 110V, As indicated by B in FIG. 10, the temperature increase rate is higher than that in the case where the power supply voltage is 100 V, and the predetermined standby temperature is reached in a short time. On the other hand, when the input power supply voltage is as low as 90V, as shown in FIG. 10C, the temperature increase rate is lower than that in the case where the power supply voltage is 100V and reaches a predetermined standby temperature in a long time.
[0070]
As described above, when the CPU 100 detects the power supply voltage input to the color printer, the CPU 100 performs control so as to change the set temperature when the fixing process is performed according to the power supply voltage, as shown in FIG.
[0071]
If the power supply voltage input to the color printer is 100 V or more and less than 110 V, the temperature shift amount is set to ± 0 ° C. as shown in FIG. The Further, when the power supply voltage input to the color printer is 110 V or more and less than 120 V, the temperature shift amount is set to −2 ° C., which is 2 ° C. lower than a predetermined set temperature (for example, 170 ° C.). The temperature is controlled (168 ° C.). Further, when the power supply voltage input to the color printer is 85V or more and less than 90V, the temperature shift amount is set to + 7 ° C., and is a temperature 7 ° C. higher than a predetermined set temperature (for example, 170 ° C.). (177 ° C.).
[0072]
As described above, in this embodiment, since the set temperature of the heating roll 702 for performing the fixing process is changed in accordance with the power supply voltage input to the color printer, the power supply voltage of the apparatus is a specified value. Therefore, it is possible to prevent a fixing defect, a high temperature offset or a low temperature offset from occurring, and to always form an image with a good image quality.
[0073]
In the above-described embodiment, the setting temperature of the heating roll 702 for performing the fixing process is changed according to the power supply voltage input to the color printer. However, the fixing is performed according to the power supply voltage input to the color printer. You may comprise so that the fixed number of sheets per unit time may be changed with the set temperature of the heating roll which processes, or independently. For example, when the power supply voltage input to the color printer is lower than a specified value, the print voltage may be changed to 14 prints / minute, which is smaller than the normal 15 prints / minute. When the number of fixed sheets per unit time is changed, it may of course be configured to control in multiple stages in accordance with the power supply voltage input to the color printer, like the set temperature.
[0074]
Further, in the embodiment, the set temperature of the heating roll 702 for performing the fixing process is changed according to the power supply voltage input to the color printer. However, the fixing is performed according to the power supply voltage input to the color printer. The heating roll 702 for processing may be configured to change the set temperature or the number of fixings per unit time, or the number of fixings that can be processed independently or the fixing limit.
[0075]
Here, the number of fixed sheets that can be processed independently is changed from 100 sheets to 50 sheets when the input power supply voltage is low, for example, according to the power supply voltage input to the color printer. Is done. In addition, as a fixing limitation, for example, depending on the power supply voltage input to the color printer, normally, waiting for 1 minute is performed when 100 sheets are continuously printed, and waiting for 3 minutes when 100 sheets are continuously printed. To be changed.
[0076]
【The invention's effect】
As described above, according to the present invention, even when the power supply voltage of the apparatus fluctuates from a specified value, it is possible to provide a fixing device that can always form an image with good image quality and an image forming apparatus using the same. can do.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a control circuit of a tandem type full-color printer as an image forming apparatus according to Embodiment 1 of the present invention.
FIG. 2 is an overall configuration diagram showing a tandem type full-color printer as an image forming apparatus according to Embodiment 1 of the present invention.
FIG. 3 is a block diagram showing a print head device of a tandem type full color printer as an image forming apparatus according to Embodiment 1 of the present invention.
FIG. 4 is an external perspective view showing a fixing device.
FIG. 5 is a sectional configuration diagram showing a fixing device according to Embodiment 1 of the present invention.
FIG. 6 is an external perspective view showing a pressure contact member.
FIG. 7 is an exploded perspective view showing a pressure contact member.
FIG. 8 is a block diagram showing a fixing device according to Embodiment 1 of the present invention.
FIG. 9 is a graph showing temperature control of the fixing device according to the first embodiment of the present invention.
FIG. 10 is a graph showing a temperature increase rate of the fixing device according to the first embodiment of the present invention.
FIG. 11 is a chart showing a relationship between a power supply voltage input to a color printer in which the fixing device according to Embodiment 1 of the present invention is used and a set temperature of the fixing device.
[Explanation of symbols]
70: fixing device, 100: CPU (control means), 701: heating source, 702: heating roll, 703: fixing belt, 704: belt guide member, 705: pressure contact member.

Claims (5)

The pressure member is pressed against the heating member,
Wherein the nip portion formed between the heating member and the pressure member, a fixing device that performs fixing by passing the recording medium bearing an unfixed toner image,
Detecting the temperature rise rate of the heating member,
Detecting a power supply voltage value input to the apparatus body in which the fixing device is used from the detected temperature rise rate ,
In the fixing device that changes the fixing parameter according to the detected power supply voltage value ,
Comprising storage means for storing the detected temperature rise rate;
A fixing device using a temperature increase rate stored in the storage means when the temperature of the heating member is equal to or higher than a predetermined temperature when the apparatus main body is turned on. The fixing device according to claim 1, wherein the fixing parameter of the fixing device is at least one of a set temperature, the number of fixings per unit time, the number of fixings that can be processed continuously, and a fixing limit. . The fixing device according to claim 1 , wherein the temperature increase rate of the heating member is detected by a time during which the temperature of the heating member changes in a predetermined temperature section. 4. The fixing device according to claim 1 , wherein a fixing parameter of the fixing device is changed according to an installation environment of an apparatus main body in which the fixing device is used. After transferring toner images of different colors formed on a plurality of image carriers onto a recording medium via one or more intermediate transfer members, a heating roll having a heating source therein and an endless belt It is formed between the heating roll and the fixing belt by a fixing device including the formed fixing belt and a pressure contact member that is disposed inside the fixing belt and presses the fixing belt against the surface of the heating roll. the nip portion, there is provided an image forming apparatus for forming an image by fixing by passing the recording medium bearing an unfixed toner image,
Detecting the temperature rise rate of the heating member,
Detecting a power supply voltage value input to the apparatus body in which the fixing device is used from the detected temperature rise rate ,
In the fixing device that changes the fixing parameter according to the detected power supply voltage value ,
Comprising storage means for storing the detected temperature rise rate;
An image forming apparatus characterized in that when the temperature of the heating member is equal to or higher than a predetermined temperature when the apparatus main body is turned on, the temperature increase rate stored in the storage means is used .

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