JP7254507B2 - image heating device - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention is an image heating device suitable for use as a heat fixing device for fixing an image as a permanent fixed image by heating a recording material on which an unfixed toner image is formed and supported, for example, in an image forming apparatus such as a copier or a printer. It is related to the device.

2. Description of the Related Art Conventionally, as an image heating apparatus for a recording material for heat fixing of an image, for example, one using a heat roller system is known. The heat roller method has a heat roller as a heating body maintained at a predetermined temperature and a pressure roller as a pressurizing body that presses against the heat roller. The toner image is fixed on the recording material P by introducing the recording material P and heating it while nipping and conveying it.

On the other hand, in recent years, image heating apparatuses are required to save power and shorten the wait time (shorten the first printout time). Therefore, an image heating apparatus using a film heating method other than the heat roller method is known. The film heating method consists of a heater as a heat source, a heater support (hereinafter referred to as a film guide), a stay that transmits pressure to the film guide, and a heat-resistant film as a flexible endless belt (hereinafter referred to as a film). , and a pressure roller as a pressure body. The film is conveyed while being pressed against the heater, and the pressure roller brings the recording material as the material to be heated into close contact with the heater through the film. In this way, in the film heating type image heating apparatus, the heat of the heater is applied to the recording material through the film at the nip portion formed by the heater and the pressure roller, so that the recording material is formed and carried on the surface of the recording material. The unfixed image is heat-fixed on the surface of the recording material. In such a film heating type image heating apparatus, a heater with a low heat capacity can be used, and power consumption and waiting time can be shortened as compared with a heat roller type apparatus (for example, Patent Document 1).・See 2).

The image heating device of the film heating method can be used for recording materials of the maximum size that can be fixed by the image heating device (hereafter referred to as large-size paper), and for recording that is narrower than the length L in the axial direction of the film compared to large-size paper. A toner image formed on a material (hereinafter referred to as small size paper) can be fixed. In a film heating type image heating apparatus, when small-size paper is continuously passed through, the temperature of the non-sheet-passing portion of the image heating apparatus may rise (temperature rise in the non-sheet-passing portion). If a recording material having a width of about 2/3 of the length L in the axial direction, which is a small size paper, is continuously passed through the substantially central portion of the film in the axial direction, heat is not taken away by the recording material in the non-sheet-passing portions. Therefore, the pressure roller has a higher temperature in the area corresponding to the paper passing portion where heat is taken away by the recording material than in the area corresponding to the non-paper passing portion where heat is not taken away by the recording material. As a result, due to thermal expansion, the pressure roller has a larger outer diameter in the area corresponding to the paper non-passage area than in the area corresponding to the paper non-passage area, and the pressure roller communicates with the end portion corresponding to the paper non-passage area. A peripheral speed difference occurs between the central portion corresponding to the paper portion, and this peripheral speed difference causes the film to sag in the vicinity of the central portion.

The recording material enters the nip portion after being pushed down along the slackened film at the central portion of the film. Enter the nip. For this reason, there is a problem that the timing at which the recording material enters the nip portion is slightly different between the central portion and the both end portions, and wrinkles may occur in the recording material.

As a countermeasure to this paper wrinkle, for example, a member that suppresses film distortion (hereinafter referred to as a distortion suppression member) is placed at an arbitrary position on the stay inside the film, and distortion is prevented by regulating the trajectory of the film. A method for doing so is known (for example, Patent Document 3).

In this method, by providing the stay with a distortion suppressing member, the film is prevented from being distorted when the temperature of the non-sheet-passing portion rises. As a result, even when the temperature of the non-paper-passing area rises, the film's rotation trajectory does not change in the longitudinal direction, and the timing at which the leading edge of the paper enters the fixing nip is the same at the center and both ends, thereby reducing paper wrinkles. Suppress the occurrence.

JP-A-4-44075 JP-A-4-204980 JP-A-10-247026

In the configuration in which the strain suppressing member is arranged on the stay inside the film, as a result of the film coming into contact with the strain suppressing member, there is a problem that the slidability deteriorates and the inner peripheral surface of the film is scraped. If the inner peripheral surface of the film is scraped, the thickness of the film is reduced only at the corresponding portion, which may cause image defects such as streaks.

Therefore, the present invention provides an image heating apparatus that suppresses abrasion of the inner peripheral surface of the film, suppresses the occurrence of image defects, and is compatible with a longer life in a configuration in which a distortion suppressing member is arranged. aim.

In order to achieve the above object, an image heating apparatus according to the present invention comprises: a cylindrical film that rotates while being in contact with a recording material; an elongated heating element arranged in the inner space of the film ; a support member arranged in the inner space of the film for supporting the heating element; a reinforcing member arranged in the internal space of the film for suppressing deformation of the support member; and a nip portion formed with the heating element through the film and a rotating body for fixing the toner image on the recording material by heating the recording material carrying the toner image while the recording material is held and conveyed by the rotation of the rotating body, the image heating device comprising: The image heating device has a lubricant supplying member fixed to the reinforcing member, which contacts an inner peripheral surface of the film when the film is deformed, and supplies a lubricant to the film, and the lubricant supplying member. comprises a lubricant supply unit that supplies lubricant to the film by contact with the film, a base unit that supports the lubricant supply unit, a lubricant that is stored, and a lubricant that is supplied to the lubricant supply unit. It has a lubricant reservoir for supplying, and the lubricant reservoir is covered with the lubricant supply .

With the configuration according to the present invention, even when a large amount of small-sized paper, which tends to raise the temperature of the non-sheet passing portion, is passed, the inner peripheral surface of the film is scraped by the distortion suppressing member, and an image defect occurs. Therefore, it is possible to provide an image heating apparatus capable of extending the life of the image heating apparatus.

FIG. 1 is a schematic configuration diagram showing a main part of an image forming apparatus according to the present invention; Schematic configuration diagram showing a main part of an image heating apparatus in an embodiment. The figure which shows the external appearance of the stay in the state which arrange|positioned the distortion suppression member in an Example. Sectional drawing of the distortion suppression member in an Example The figure which shows the external appearance of the distortion suppression member in an Example. The figure which shows another example of a structure in an Example. Sectional drawing of the distortion suppression member in the modification 1 The figure which shows the external appearance of the distortion suppression member in the modification 1. FIG. 10 is a diagram showing the appearance of a distortion suppressing member in the configuration of Modification 1;

[Example]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(1) Image Forming Apparatus FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus provided with an image heating apparatus of this embodiment. In this embodiment, the image forming apparatus 100 will be described by exemplifying a laser printer using a transfer type electrophotographic process.

The image forming apparatus 100 includes a cartridge 120 having a photosensitive drum 101 as an image bearing member, a charging means 102 such as a contact charging roller, a developing device 104 and a cleaning device 105 . The photosensitive drum 101 is rotationally driven counterclockwise as indicated by an arrow at a predetermined peripheral speed (process speed). The charging unit 102 uniformly charges (primary charging) the circumferential surface of the photosensitive drum 101 to a predetermined polarity and potential. A laser beam emitted from a laser scanner 103 scans and exposes (irradiates) the charged surface of the photosensitive drum 101 that has been primarily charged. A laser scanner 103 as image exposure means outputs a laser beam that is ON/OFF modulated in response to time-series electrical digital pixel signals of target image information input from an external device such as an image scanner or computer (not shown). As a result, the photosensitive drum 101 is freed from charges in the exposed light portion of the peripheral surface of the photosensitive drum 101 by this scanning exposure, and an electrostatic latent image corresponding to the desired image information is formed.

The developing device 104 includes a developing sleeve carrying developer on its surface. A developer (toner) is supplied from a developing sleeve of the developing device 104 to sequentially develop the electrostatic latent images formed on the peripheral surface of the photosensitive drum 101 as toner images. In the case of a laser printer, generally, a reversal development method is used in which toner is applied to the exposed light portion of the electrostatic latent image for development.

The recording materials P are stacked and housed in a paper feed cassette 109 which is detachable from the image forming apparatus 100 . In the image forming apparatus 100 according to the present embodiment, the maximum sheet passing width is A4 size (paper width: 210 mm). The image forming apparatus 100 includes a sheet path including a sheet feeding roller 108 that separates and feeds the recording material P one by one, a conveying roller 110 that conveys the recording material P, a registration roller 111 that adjusts the feeding timing of the recording material P, and the like. 112. The recording material P in the paper feed cassette 109 is separated and fed one by one by driving the paper feed roller 108 based on the paper feed start signal, passes through the sheet path 112, and passes through the photosensitive drum 101 and the transfer roller. (Transfer member) 106 is introduced into the transfer portion at a predetermined timing. That is, when the leading edge of the toner image on the photosensitive drum 101 reaches the transfer section, the registration roller 111 controls the conveyance of the recording material P so that the leading edge of the recording material P also reaches the transfer section. be done.

The recording material P introduced into the transfer portion is nipped and conveyed at this transfer portion, and during this time, a predetermined controlled transfer voltage (transfer bias) is applied to the transfer roller 106 from a transfer bias application power source (not shown). The transfer roller 106 is generally an elastic sponge in which a semiconductive sponge elastic layer adjusted to a resistance of about 1×10 ⁶ to 1×10 ¹⁰ Ω is formed on a metal core made of Fe or the like with carbon, ion conductive filler, or the like. Rollers are used. In this embodiment, an ion-conducting transfer roller is used in which a conductive elastic layer formed by reacting NBR rubber and a surfactant is concentrically and integrally formed around the outer circumference of a cored bar. Resistance values used ranged from 1×10 ⁸ to 5×10 ⁸ Ω.

A transfer bias having a polarity opposite to that of the toner is applied to the transfer roller 106 , thereby electrostatically transferring the toner image formed on the peripheral surface of the photosensitive drum 101 onto the surface of the recording material P at the transfer portion. The recording material P onto which the toner image has been transferred is conveyed and introduced from the transfer unit through the sheet path 113 to the image heating device 107, where fixing processing for heating and pressing the toner image is performed. Then, the recording material P on which the toner image is fixed by the image heating device 107 passes through the sheet path 114 and is discharged onto the paper discharge tray 115 from the paper discharge port, completing the image formation.

On the other hand, after the toner image is transferred to the recording material P, the peripheral surface of the photosensitive drum 101 is cleaned by a cleaning device 105 consisting of a blade to remove residual toner, paper dust, etc., and is primarily charged again for the next image formation. used for

(2) Image Heating Device Next, the image heating device 107 in this embodiment will be described. FIG. 2 is a schematic configuration diagram of the film heating type image heating device 107 according to the present embodiment.

The image heating device 107 includes a heater (heating body) 3, a film guide (supporting member) 1 that holds the heater 3, a stay (reinforcing member) 2 that transmits pressure to the film guide 1, and a periphery of the film guide 1. and a pressure roller (rotating body) 4.

The film guide 1 is a member having heat resistance and rigidity and having a supporting function of holding the heater 3 and a film guiding function of guiding the rotation of the film 4 . The film guide 1 can be made of a highly heat-resistant resin such as polyimide, polyamide-imide, PEEK, PPS, or liquid crystal polymer, or a composite material of these resins and ceramics, metal, glass, or the like. A liquid crystal polymer was used in this embodiment.

The stay 2 reliably transmits the pressure force obtained by the pressure spring of the pressure mechanism (not shown) to the film guide 1, and forms a nip portion N between the pressure roller 5 and the heater 3 via the film 4. It is for The stay 2 requires rigidity and is generally made of a metal material. In this embodiment, iron is used as the material of the stay 2 .

The film 4 is fitted around a film guide 1 functioning as a film guide member holding a heater 3 , and is rotatable around the film guide 1 while its inner peripheral surface is in contact with the heater 3 . In order to reduce the heat capacity and shorten the wait time (first printout time), the film thickness of the film 4 is preferably 450 μm or less and 20 μm or more. As the film 4, a single-layer film such as heat-resistant PTFE, PFA, FEP, etc., or a multi-layer film obtained by coating a film such as polyimide, polyamideimide, PEEK, PES, PPS with PTFE, PFA, FEP, etc. is used. be able to. In this example, a polyimide film having a film thickness of about 60 μm coated with PFA on the outer peripheral surface was used. The thickness of the PFA coating layer was about 15 μm. The outer diameter of the film 4 was 24 mm. The base layer of the film 4 may be made of not only the above resin materials but also metal materials such as SUS. In order to improve image quality, heat-resistant rubber such as silicone rubber may be formed as an elastic layer between the base layer and the coating layer.

A pressure roller 5 as a driving means for the film 4 forms a nip portion N with the film 4 sandwiched between itself and the heater 3 and causes the film 4 to be driven to rotate. The pressure roller 5 is composed of a metal core 5a, an elastic layer 5b, and an outermost surface layer 5c, and is placed in pressure contact with the surface of the heater 3 with the film 4 interposed therebetween. In this embodiment, the metal core 5a is made of aluminum, the elastic layer 5b is made of silicone rubber, and the surface layer 5c is made of PFA tube having a thickness of about 50 μm. The pressure roller 5 has an outer diameter of 25 mm, and the elastic layer 5b has a thickness of about 3 mm.

The pressure roller 5 is rotationally driven by a motor M in the clockwise direction indicated by the arrow at a predetermined peripheral speed. In the film 4, the rotational force is transmitted from the pressure roller 5 to the film 4 by the frictional force between the pressure roller 5 and the outer peripheral surface of the film 4 at the nip portion N, and the inner peripheral surface of the film 4 reaches the heater 3 at the nip portion N. While being slid, it is driven to rotate. In this manner, the film 4 was moved counterclockwise around the film guide 1 at a speed substantially equal to that of the circumferential surface of the pressure roller 5, and was made to rotate.

A ceramic heater is specifically used as the heater 3 , which is arranged and held on the lower surface of the film guide 1 along the longitudinal direction of the film guide 1 . FIG. 6 shows a sectional view of the heater 3 in this embodiment. The heater 3 has a substrate 3a, a resistance heating element 3b formed on the film sliding surface side of the substrate 3a, and an insulating protective layer 3c protecting the surface of the heater on which the resistance heating element 3b is formed. The heater 3 is held and fixed to the lower surface side of the film guide 1 in a state in which the surface side of the substrate 3a on which the resistance heating element 3b and the insulating protective layer 3c are formed faces downward so as to face the film 4. .

The substrate 3a has an elongated shape whose longitudinal direction is perpendicular to the conveying direction of the recording material P, and is made of a material having heat resistance, insulation and thermal conductivity. A ceramic material such as aluminum oxide or aluminum nitride is used for the substrate 3a having heat resistance and insulation. The resistance heating element 3b is formed on the substrate 3a by screen printing a paste prepared by kneading silver palladium, glass powder (inorganic binder) and organic binder. The insulating protective layer 3c is formed so as to cover the resistance heating element 3b formed on the substrate 3a, and in addition to the electrical insulation between the surface of the heater 3 and the outside, the slidability with the film 4 can be ensured. is configured to In this example, a heat-resistant glass layer was used as the insulating protective layer 3c.

The temperature of the heater 3 can be detected by a temperature detecting element (thermistor) 6 . In this embodiment, an external contact type thermistor separated from the heater 3 is used as the temperature detecting element 6 .

The heater 3 raises the temperature by supplying power to the resistance heating element 3b and generating heat over the entire length of the resistance heating element 3b. This temperature rise is detected by the thermistor 6, and the output of the thermistor 6 is A/D converted and input to a CPU (not shown). etc., the temperature of the heater 3 is controlled. That is, the heater 3 is maintained at a constant temperature during fixing by controlling the power supply so that the temperature of the heater 3 rises when the temperature detected by the thermistor 6 is lower than a predetermined set temperature, and decreases when the temperature is higher than the set temperature. be

After the temperature of the heater 3 is raised to a predetermined temperature and the film 4 is driven to rotate by the pressure roller 5 , the toner is transferred to the nip portion N formed by the heater 3 and the pressure roller 5 through the film 4 . The recording material P onto which the image has been transferred is conveyed from the transfer section. As the recording material P is nipped and conveyed together with the film 4 at the nip portion N, the heat of the heater 3 is applied to the recording material P through the film 4, and the unfixed toner image on the recording material P is heated. • Pressurized and fixed on the recording material P; The recording material P that has passed through the nip portion N is separated from the film 4 and further conveyed.

(3) Distortion Suppression Member FIG. 3 shows the distortion suppression member 7 attached to the stay 2 . The distortion suppressing member 7 is installed to suppress the distortion of the film that causes wrinkles, and is installed on the stay 2 to fill the space between the film 4 and the stay 2 inside the film, thereby adjusting the trajectory of the film. and suppress distortion. As the position where the distortion suppressing member 7 is installed, the area of the stay 2 located exactly opposite to the nip portion N with respect to the heater 3 is desirable. It was installed in an area containing In the area of the stay 2 located directly opposite to the nip portion N with respect to the heater 3, there is no film guide 1, and gravity may act, causing the trajectory of the film 4 to deviate from its original position. Easy to contact. Therefore, in order to regulate the trajectory of the film 4 and suppress the distortion of the film 4, it is effective to install the distortion suppressing member 7 at this portion. The distortion suppressing member 7 is vertically above a horizontal dashed line L intersecting at the midpoint of the height of the film 4 in the dashed line V extending vertically from the center of the nip portion N in the conveying direction of the recording material P. It is preferably provided at the position (the side pointed by the arrow Z). Further, in this embodiment, in the direction (longitudinal direction) perpendicular to the conveying direction of the recording material P, when the recording material P is passed, the center line of the recording material P passes through a certain reference position (the center of the paper passing). It was configured to be aligned in the following manner. Therefore, in this embodiment, the distortion suppressing members 7 are provided symmetrically in the longitudinal direction from the paper-passing center of the stay 2, one at each of positions separated by 35 mm from the paper-passing center at one end and the other end in the longitudinal direction. It was configured. The distortion suppressing member 7 is curved along the stay 2 and has a symmetrical shape with respect to the vertex of the stay 2 with the longitudinal direction of the film 4 as a short side and the rotation direction of the film 4 as a long side. Note that the size, shape, number, and the like of the distortion suppression member 7 vary depending on each fixing device, and are not limited to the configuration shown here.

Next, the strain suppressing member 7 of this embodiment will be described. FIG. 4 is a cross-sectional view of the distortion suppressing member 7. As shown in FIG. The strain suppression member 7 includes a lubricant storage portion 7a in which lubricant is stored, a lubricant supply portion 7b in which the lubricant is soaked, a strain suppression member base portion 7c that supports the lubricant supply portion 7b, have

The lubricant storage portion 7a is provided in the distortion suppressing member base portion 7c, and lubricant is stored therein. The lubricant supply part 7b is a sheet-like member, and is arranged so as to be adhered so as to cover the opening of the lubricant storage part 7a. The portion 7b comes into contact with the inner peripheral surface of the film 4 and suppresses distortion of the film 4. As shown in FIG. The lubricant supply part 7b may be any member as long as it is impregnated with a lubricant, preferably a fiber layer such as felt, and examples of the material include aramid fiber, glass fiber, and carbon fiber. In this embodiment, aramid fiber felt is used as the lubricant supply portion 7b. The distortion suppressing member base portion 7c is a member adhered to the stay 2, and is required to have heat resistance and rigidity to suppress deformation of the film. As a material for the distortion suppressing member base portion 7c, highly heat-resistant resins such as polyimide, polyamideimide, PEEK, PPS, and liquid crystal polymer, composite materials of these resins and ceramics, metals, glass, or the like are desirable. In this embodiment, a liquid crystal polymer is used as the material of the distortion suppressing member base portion 7c.

As the lubricant, heat-resistant materials such as grease obtained by thickening a perfluoropolyether base oil with a fluororesin, silicone oil such as dimethyl silicone, and the like may be used. In this example, a grease obtained by thickening a perfluoropolyether base oil with a fluororesin was used.

FIG. 5 is a view of the distortion suppressing member 7 viewed from the direction of arrow α in FIG. In this embodiment, substantially the entire surface of the distortion suppressing member 7 that contacts the film 4 is constituted by the lubricant supply portion 7b. By adopting the configuration of this embodiment, even when the film 4 is bent and contacts the inner peripheral surface of the film 4, the contact with the lubricant supply portion 7b impregnated with the lubricant is more effective than in the conventional art. The state in which the film 4 rotates smoothly can be maintained for a long period of time. As a result, it is possible to prevent the inner peripheral surface of the film 4 from being scraped and the occurrence of streaks in the image.

Table 1 below shows the results of comparison of streak occurrence between the configuration of the present embodiment and the configuration of the comparative example. The configuration of the comparative example follows the configuration of this embodiment, the diameter of the film and pressure roller is φ24 mm, the heater is a ceramic heater, and the film guide and stay have the same configuration as that of this embodiment. A different point is that the distortion suppressing member 7 is not provided. As a condition of the endurance test conducted for comparison, A5 size glossy paper was continuously fed.

Periodic checks were performed every 50,000 sheets to confirm the occurrence of streaks. As a method for checking the occurrence of streaks, 100 sheets of A5 size glossy paper were passed continuously, and the number of sheets on which streaks occurred was checked on the last 10 sheets (91st to 100th sheets) when the temperature of the non-passing area was increased. bottom.

As a result, in the configuration of the comparative example, streaks begin to appear around 200,000 sheets. On the other hand, in the configuration of the present embodiment, even when 400,000 sheets of paper were fed, no such problem occurred.

As described above, the strain suppression member 7 is provided with the lubricant storage portion 7a, and the lubricant supply portion 7b is arranged so as to cover the opening thereof, so that the contact portion between the strain suppression member 7 and the film 4 is constantly lubricated. It becomes possible to supply the agent. As a result, the lubricating agent is always interposed between the inner peripheral surface of the film 4 and the distortion suppressing member 7, thereby suppressing the scraping of the film 4 and achieving a longer life than before.

In the present embodiment, the above configuration is used as an example of the configuration of the strain suppressing member 7, but the number, shape, installation position, etc. of the strain suppressing member are not limited. Therefore, for example, if the space between the film and the stay is small because the diameter of the film is small, and the distortion suppressing member cannot be placed, part of the stay is notched and a hole is made in the part where the distortion suppressing member is installed. It is good also as a structure which provides and arrange|positions a distortion suppression member.

In addition, although the structure having both the lubricant supply section and the lubricant storage section has been described as an example in this embodiment, the lubricant supply section may be impregnated with a lubricant without having the lubricant storage section. .

As for the heating body, although the heating body is in the nip and the endless film slides in the present embodiment, the heating body is not limited to this. For example, it is possible to obtain the same effect by adopting the configuration of this embodiment even in a configuration that does not slide on an endless film such as a halogen heater. Furthermore, the same effect can be obtained by adopting the configuration of this embodiment even in the heating and fixing configuration of the electromagnetic induction heating system in which the endless film itself generates heat without having a heating member.

In addition, as shown in FIG. The image heating apparatus may have an endless pressing rotary member 10 forming the fixing nip portion N1. In this case, the surface of the fixing rotary member 9 is heated by the heating rotary member 8 at the heating nip portion N2, and the toner image is heated and fixed on the recording material while the recording material carrying the toner image is nipped and conveyed at the fixing nip portion N1. do. By adopting the configuration of this embodiment in such a configuration as well, the same effect can be obtained in the endless heating rotating member 8 and the endless pressing rotating member 10 .

Furthermore, the distortion suppressing member is not limited to the configuration according to the embodiment. For example, when the width of the strain-reducing member is wide, the pressure that the film-contacting surface of the strain-reducing member receives from the film differs depending on the location. Therefore, the pressure applied to the lubricant supply portion located on the surface of the distortion suppressing member also varies depending on the location, and as a result, there are cases where the lubricant cannot be uniformly supplied to the inner peripheral surface of the film within the plane of the lubricant supply portion. be. Therefore, by providing a supporting portion on a part of the surface of the strain suppressing member that contacts the film to increase the strength of the strain suppressing member, it becomes possible to supply the lubricant to the strain suppressing member while suppressing the strain of the film. Modification 1 of this embodiment relating to an image heating apparatus having a distortion suppressing member having a supporting portion will be described below.

In Modification 1, only the distortion suppressing member 7 is different from the embodiment, and the rest of the configuration of the image heating apparatus is the same as that of the embodiment. 7 is a cross-sectional view of the strain suppressing member 7 according to Modification 1, and FIG. 8 is a view of the strain suppressing member 7 according to Modification 1 as viewed from the direction of arrow α in FIG. The basic structure of the strain suppressing member 7 is the same as that of the strain suppressing member of the embodiment, and consists of a lubricant storage portion 7a, a lubricant supply portion 11b, and a strain suppressing member base portion 7c.

In Modification 1, the strain suppression member base portion 7c has the support portions X1 and X2. That is, the support portions X1 and X2 are arranged so as to be adjacent to the lubricant storage portion 7a. X1 and X2 are positioned, and a plurality of lubricant reservoirs 7a are divided. At this time, the surfaces of the support portions X1 and X2 that come into contact with the film 4 do not have a level difference with the surfaces of the lubricant supply portion 7b that come into contact with the film 4, and the corner portions of the support portions X1 and X2 or the lubricant supply portion 7b are aligned with the film 4. It is configured so that it does not come into contact with

In this manner, the film 4 is configured to be in contact with the lubricant supply portion 7b and the support portions X1 and X2 of the distortion suppression member 7. As shown in FIG. Compared to the embodiment, in the present modified example 1, since the support portions X1 and X2 are formed of the liquid crystal polymer forming the base portion 11c of the distortion suppressing member, the strength of the lubricant supply portion 7b is stronger than that of the lubricant supply portion 7b formed of the felt material. is high. Therefore, even when the width of the distortion suppressing member 7 is increased in the longitudinal direction, the film 4 can be supported by the support portions X1 and X2 and the distortion of the film 4 can be suppressed. At the same time, the lubricant is supplied to the surface of the distortion suppression member 7 by the lubricant supply portion 7b, so that even when the film 4 and the support portions X1 and X2 are in contact with each other, the support portions X1 and X2 Scraping of the inner peripheral surface of the film 4 can be suppressed, and a longer life of the image forming apparatus can be achieved.

In addition, although Modification 1 has been described using the above configuration as an example of the configuration of the strain suppression member, the configuration of the strain suppression member is not limited to the number, shape, installation position, material, and the like. In Modification 1, the longitudinal direction of the lubricant supply portion 11b (lubricant storage portion 7a) is along the rotation direction of the film 4, and the support portions X1 and X2 are configured to extend in the rotation direction of the film 4, but this is not the only option. Instead, for example, the configuration shown in FIG. 9 may be used. That is, as shown in FIG. 9A, the lubricant supply portion 11b (lubricant storage portion 7a) may be divided into a plurality of portions by the support portions X1 and X2 extending in the direction intersecting the rotation direction of the film 4. good. Furthermore, as shown in FIG. 9(b), the longitudinal direction of the lubricant supply portion 11b (lubricant storage portion 7a) is along the direction orthogonal to the rotation direction of the film 4, and the support portions X1 and X2 of the film 4 It is good also as a structure extended in the direction orthogonal to a rotation direction. In addition, as shown in FIG. 9(c), the lubricant supply portion 11b (lubricant storage portion 7a) may be divided into a plurality of portions by intersecting support portions X1 and X2. In addition, as shown in FIG. 9(d), a configuration may be adopted in which a plurality of support portions X surrounded by the lubricant supply portion 11b (lubricant storage portion 7a) are arranged.

REFERENCE SIGNS LIST 1 film guide 2 stay 3 heater 4 film 5 pressure roller 6 temperature detection element (external contact type thermistor)
7 distortion suppression member 8 heating rotator 9 fixing rotator 10 pressure rotator N nip portion P recording material T toner a recording material conveying direction

Claims (7)

a cylindrical film that rotates while being in contact with the recording material;
an elongated heating element disposed in the interior space of the film ;
a support member arranged in the internal space of the film and supporting the heating element;
a reinforcing member disposed in the internal space of the film for suppressing deformation of the supporting member;
a rotating body forming a nip portion with the heating body through the film ;
and fixing the toner image to the recording material by heating the recording material carrying the toner image by the rotation of the rotating body while nipping and conveying the recording material in the nip portion ,
The image heating device has a lubricant supplying member fixed to the reinforcing member, which contacts the inner peripheral surface of the film when the film is deformed, and supplies lubricant to the film,
The lubricant supply member includes a lubricant supply portion that supplies lubricant to the film by coming into contact with the film, a base portion that supports the lubricant supply portion, and a lubricant that stores and supplies the lubricant. having a lubricant reservoir for supplying lubricant to the
The lubricant reservoir is covered by the lubricant supply
An image heating device characterized by: 2. The image heating apparatus according to claim 1, wherein a plurality of said lubricant supply members are provided in the longitudinal direction of said heating body . The image heating device is aligned so that the center line of the recording material passes through a fixed reference position in the longitudinal direction of the heating member , and the recording material is conveyed to the nip portion,
3. The image heating apparatus according to claim 2 , wherein the lubricant supply section is arranged symmetrically with respect to the reference position of the reinforcing member in the longitudinal direction of the heating body . 2. An image heating apparatus according to claim 1 , wherein the base portion has a support portion adjacent to the lubricant supply portion, which supports the film by coming into contact with the film when the film is deformed. . 5. The image heating apparatus according to claim 4 , wherein the surface of the support portion that contacts the film is formed without a step from the surface of the lubricant supply portion that contacts the film. 6. An image heating apparatus according to claim 4 , wherein said support portion is a part of said base portion positioned between said plurality of said lubricant supply portions. 6. An image heating apparatus according to claim 4 , wherein said support portion is arranged at a position surrounded by said lubricant supply portion.

Images