JP4974069B2 - Recording material separating member of fixing device - Google Patents

Description

  The present invention relates to a recording material separating member for separating a recording material (fixing member) from a fixing member such as a fixing roller or a fixing belt which is preferably used in a toner fixing device such as an image forming apparatus such as a copying machine or a printer. It is.

  Conventionally, in a toner fixing device, a separation claw is used to separate a recording material (fixing member) from a fixing member such as a fixing roller. In a toner fixing device using such a separation claw, a local part is used. There is a concern that the life of a fixing member such as a fixing roller may be shortened due to a constant pressure. In view of this, a plate-shaped recording material separating member is used instead of the separating claw, and a proposal has been made to prevent the life from being shortened by being arranged close to or in line contact with a fixing member such as a fixing roller.

  Specifically, an apparatus in which a plastic sheet having a thickness of 0.05 mm or more is fixed to a metal plate as a plate-like separating member has been proposed (see Patent Document 1). However, as in this proposal, the plastic sheet alone has low rigidity and there is a concern that the recording material separation function may be lowered.

  As another plate-like separation member, a separation member in which a fluororesin film is attached to a metal plate has been proposed (see Patent Document 2). However, in this proposal, it is difficult to apply a fluororesin film to a metal plate without removing foreign matter, and the yield is difficult, and the thickness of the adhesive is difficult to control, and the non-adhesiveness of the toner is reduced.

As another plate-like separation member, a separation member in which an elastomer layer is formed on a metal core and a fluororesin film is formed on the surface is proposed (see Patent Document 3). However, this proposal also has a problem in that the non-adhesiveness of the toner is reduced due to the difficulty in controlling the yield of film adhesion and the thickness of the elastomer layer as in the proposal of Patent Document 2.
JP 59-188681 A JP 2001-235959 A JP-A-2005-234131

  SUMMARY OF THE INVENTION An object of the present invention is to provide a recording material separating member for a fixing device that is excellent in heat resistance and non-toner adhesion and has excellent durability in a plate-shaped recording material separating member used in a fixing device such as a copying machine or an image forming apparatus. It is to provide.

The recording material separating member of the fixing device of the present invention is a plate-shaped separating member for separating the recording material in the fixing device from the fixing member, and the separating member is formed of a fluororesin melted on the surface of the core material. der which fixed are integral at is, the surface of the separating member is a fluororesin, the separating member does not exist covering layer.

According to a preferred aspect of the recording material separating member of the fixing device of the present invention, the core material is formed with holes, grooves or irregularities for allowing the molten fluororesin to flow and solidify and fix , And the said core material is comprised with the metal material and the plastic material glass material.

  According to a preferred aspect of the recording material separating member of the fixing device of the present invention, the core material has a shape in which the thickness on the side for separating the recording material is thin.

  According to a preferred aspect of the recording material separating member of the fixing device of the present invention, the fluororesin is a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer. It is a polymer or a tetrafluoroethylene-ethylene copolymer.

  Since the recording material separating member of the fixing device of the present invention fixes the fluororesin melted to the core material by direct molding, the necessary rigidity can be obtained by selecting the core material. Since the fluororesin is directly molded on the core material, both the heat resistance and the non-adhesiveness of the toner can be achieved depending on the characteristics of the fluororesin. In addition, since fluororesin can be directly molded on the core material and the dimensional accuracy can be controlled, it is possible to prevent a decrease in non-tackiness of the toner due to uneven thickness of the adhesive or elastomer at the separation function portion as in the conventional case. . Furthermore, since the shape of the molded fluororesin has a degree of freedom, it is excellent in durability due to abrasion with the recording material.

  The recording material separating member of the present invention has a structure in which a portion close to or in contact with a fixing member such as a fixing roller is covered with a fluororesin having a predetermined thickness. Combines toner adhesion. Further, durability is imparted by the shape of the fluororesin that is molded against wear due to contact with the recording material. By selecting a material having rigidity such as metal as the core material, the separation member itself can be made rigid, and the rigidity can be maintained even under long-term high-temperature conditions and has durability. .

  An example of the recording material separating member of the fixing device of the present invention will be described with reference to the drawings. FIG. 1 is a schematic side view for illustrating the fixing device using the fixing device separating member of the present invention.

  In FIG. 1, the fixing device basically includes a fixing member 2 such as a fixing roller and a pressure member 3 such as a pressure roller that rotates in contact with the fixing member 2. The fixing member 2 is usually heated by a heater 2a. The recording material separating member 1 approaches or contacts the downstream side of the fixing member 2 in order to separate the recording material 4 such as paper fed from the fixing member 2 and the pressure member 3 rotating in the direction of the arrow from the fixing member 2. Has been placed. In FIG. 1, a separation member 1 is disposed in proximity to or in contact with the fixing member 2 in order to separate the recording material 4 fed by the fixing member 2 and the pressure member 3 rotating in the direction of the arrow from the fixing member 2. The recording material separating member 1 is interposed between the recording material 4 and the fixing member 2 discharged from between the fixing member 2 and the pressure member 3, and the traveling recording material 4 is peeled off from the fixing member 2. is doing.

  Although it varies depending on the model, the fixing device may be used by being exposed to a high temperature atmosphere of about 150 ° C. to 250 ° C. Therefore, it is preferable that the fixing device is composed of a heat-resistant member as much as possible.

  FIG. 2 is a perspective view for illustrating the separation member of the fixing device of the present invention. In the example of FIG. 2, the fluororesin 6 is molded around the core material 5 by injection molding and solidified and integrated. ing.

  Further, when the core material 5 is a material that is not fused with the fluororesin 6, a method may be considered in which a hole is made in the core material 5 and the fluororesin 6 is wound around and fixed as shown in FIG. With respect to the fixing method, as shown in FIG. 5 described later, a groove may be carved into the surface of the core material 5 by machining so that the fluororesin 6 is embedded. When the core material 5 is made of fluororesin 6 or the like and the surface is melted and integrated, it is not necessary to process the core material 5 in particular.

  FIG. 3 is a perspective view for illustrating a recording material separating member of another fixing device of the present invention. If there is a function of separating the recording material, the fluororesin 6 molded on the core material 5 may be divided into three portions as shown in FIG. In this example, it is divided into three parts, but it can be divided into a plurality of parts, such as two parts or five parts, due to the space of the fixing device. Further, the widths of the respective fluororesins 6 may be uniform, but are not necessarily uniform, and the interval between the fluororesins 6 can be freely set.

  FIG. 4 is an enlarged partial cross-sectional perspective view for illustrating the recording material separating member in which the core material constituting the recording material separating member of the fixing device of the present invention is punched and fixed with a fluororesin. In FIG. 4, the core material 5 constituting the recording material separating member is drilled to form a hole, and a fluororesin 6 is fixed to the core material 5.

  FIG. 5 is an enlarged partial cross-sectional perspective view illustrating the recording material separating member that is machined and fixed with a fluororesin on the surface of the core material constituting the recording material separating member of the fixing device of the present invention. In FIG. 5, the surface of the core material 5 constituting the recording material separating member is machined to form groove-shaped irregularities, and the fluororesin 6 is fixed to the core material 5.

  FIG. 6 is an example of a core material constituting the recording material separating member of the present invention, and the core material 5 is provided with holes 7 by press processing, laser processing, or the like. The core material 5 shown in FIG. 6 is placed in a mold, and a molten fluororesin 6 is poured into the mold, cooled and solidified so that the fluororesin goes around into the hole 7. Becomes the recording material separating member shown in FIG.

  FIG. 7 shows an example of a core material constituting another recording material separating member of the present invention. The core material 5 is provided with grooves 8 by milling or laser processing. The core material 5 shown in FIG. 7 is placed in a mold, melted fluororesin 6 is poured, cooled and solidified, and the fluororesin enters into the groove 8, whereby the core material 5 and fluororesin 6 are firmly integrated. The recording material separating member shown in FIG.

  About the intensity | strength of the recording material separation member of this invention, it can be made into an optimal state by selecting the material of a core material. The core material used in the present invention can be composed of a metal material, a fiber reinforced plastic material, a glass material, or the like.

  Examples of the metal material used in the present invention include iron, stainless steel, aluminum, and copper, and alloys such as brass and phosphor bronze can also be used. Of these, stainless steel is the most preferred metal material because of its rigidity and resistance to rust. Moreover, the thickness of the core material made of a metal material is preferably about 0.05 to 0.5 mm, particularly preferably about 0.1 to 0.2 mm.

  Examples of the plastic material used in the present invention include plastic materials, fiber reinforced plastic materials, and inorganic reinforced plastic materials. Examples of the plastic material include polyesters such as polyamide, polyphenylene sulfide, and polyethylene terephthalate, and polyimide materials, polyether ether ketone, polyether sulfide, and the like.

  Examples of fiber reinforced plastic materials include reinforced fibers such as glass fibers and carbon fibers, and polyester resins such as epoxy resins, polyphenylene sulfide, and polyethylene terephthalate, and polyimide resins, and polyether resins such as polyether ether ketone and polyether sulfide. The thing which consists of is mentioned.

  Examples of the inorganic reinforced plastic material include inorganic minerals such as talc and epoxy resins, polyesters such as polyphenylene sulfide and polyethylene terephthalate, and polyimide-based materials, and matrix resins such as polyether ether ketone and polyether sulfide. It is done.

  Since the fixing device may be used by being exposed to a high-temperature atmosphere of about 150 ° C. to 250 ° C. as described above, the plastic material constituting the core material may be made of a heat-resistant material as much as possible. preferable. Preferable plastic materials include heat-resistant resins such as polyphenylene sulfide, polyimide, and liquid crystal polymer.

  Examples of the glass material used in the present invention include ordinary glass, tempered glass, and composite glass.

  In the present invention, by appropriately designing the shape of the fluororesin 6 to be molded, durability against abrasion with the recording material becomes good. As shown in FIGS. 2 to 5, the core material used in the present invention has a fluororesin 6 shape only on the end side for separating the recording material in order to improve the function of separating the recording material from the fixing member. It is preferable to reduce the thickness. For example, the end portion thickness d in FIG. 2 is preferably as thin as possible, and can be preferably less than 0.5 mm. The thickness d of the tip is preferably zero, but is practically about 0.05 mm to 0.2 mm. The shape of the tip portion is arbitrary, but, for example, the recording material side gradually changes from the basic thickness of the core material in a range of about 5 mm to 10 mm from the end portion, and the thickness d of the tip portion is 0.05 mm to 0.00 mm. It can be configured to be about 2 mm.

  In the present invention, by appropriately designing the shape of the fluororesin 6 thus molded, the durability against wear with the recording material is improved, and the shape having the function of separating the recording material is formed by direct molding. Can do.

  In addition, the core material used in the present invention is preferably formed with holes (or holes), grooves, or irregularities in the core material in order to achieve strong fixation and integration with the molded fluororesin. For example, the core material is drilled as shown in FIGS. 4 and 6, or the core material is machined as shown in FIGS. 5 and 7, or the core surface is surface-treated with chemicals or the like. By forming irregularities on the surface of the material, the fluororesin molded by the anchor effect can be firmly fixed to the core material. Specifically, in FIGS. 4 and 6, the fluororesin 6 is inserted into the formed hole 7 to fix the fluororesin 6, and in FIGS. 5 and 7, the fluororesin 6 is inserted into the groove 8. Fluorine resin 6 is fixed.

  Examples of the fluororesin suitably used in the present invention include tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE), and tetrafluoroethylene-hexafluoropropylene copolymer (FEP). In addition, other fluororesins may be used as long as heat resistance and non-toner adhesion are satisfied. When it is desired to have an antistatic function, the object can be achieved by blending carbon fine powder or the like with a fluororesin.

  When forming the recording material separating member of the present invention by injection molding, a special injection molding machine with excellent corrosion resistance is used to prevent corrosion due to molten fluororesin gas, and the mold is also subjected to corrosion resistance processing. . First, a pellet-shaped fluororesin is supplied from a hopper, and a predetermined amount is measured while the fluororesin is melted by the rotation of a screw disposed in a cylinder heated to a temperature of about 350 ° C. to 400 ° C. in advance.

  Separately, a core material is placed in a mold heated to a temperature of 200 ° C to 230 ° C. After closing the mold, a fixed amount of fluororesin is poured into the mold by the advance of the screw and integrated with the core material. Since the melted fluororesin is deprived of heat by the mold and solidifies, the appropriate time is held in the mold, and then the mold is opened and the fluororesin integrated with the core material is taken out.

  The formed recording material separating member is used by being fixed to the holder of the fixing device. However, with respect to the fixing method to the holder, if the structure does not hinder the passage of the recording material, screwing, caulking, adhesion, etc. A method is possible. Further, when bonding is performed as a fixing means, surface treatment such as corona discharge processing, plasma etching processing, and addition of polarity with a primer for improving the adhesion of the bonded portion to the fluororesin is required.

  The recording material separating member of the present invention is suitably used for fixing devices such as toner image transfer type dry electrostatic copying machines, wet electrostatic copying machines, laser beam printers, liquid crystal printers, facsimile printers, and other image forming apparatuses. .

  Since the recording material separating member of the fixing device of the present invention is made of a fluororesin molded at a portion close to or in contact with a fixing member such as a fixing roller or a fixing belt, the recording material (fixing member) separation performance and Combines high temperature durability and non-toner adhesion. Since it is composed of a fluororesin molded product, it can be used for fixing devices such as image forming apparatuses such as copying machines and printers because it has excellent heat resistance and can achieve the purpose of non-adhesiveness of toner.

FIG. 1 is a schematic side view for illustrating a fixing device using a recording material separating member of the fixing device of the present invention. FIG. 2 is an enlarged partial cross-sectional perspective view for illustrating the recording material separating member of the fixing device of the present invention. FIG. 3 is an enlarged partial cross-sectional perspective view for illustrating a recording material separating member of another fixing device of the present invention. FIG. 4 is an enlarged partial cross-sectional perspective view for illustrating the recording material separating member in which the core material constituting the recording material separating member of the fixing device of the present invention is punched and fixed with a fluororesin. FIG. 5 is an enlarged partial cross-sectional perspective view illustrating the recording material separating member that is machined and fixed with a fluororesin on the surface of the core material constituting the recording material separating member of the fixing device of the present invention. FIG. 6 is an enlarged partial cross-sectional perspective view for illustrating the core material constituting the recording material separating member of the fixing device of the present invention. FIG. 7 is an enlarged partial cross-sectional perspective view for illustrating another core material constituting the recording material separating member of the fixing device of the present invention.

Explanation of symbols

1: Separation member 2: Fixing member 2 a: Heater 3: Pressurizing member 4: Recording material 5: Core material 6: Fluororesin 7: Hole 8: Groove

Claims (7)

A plate-like separation member for separating a recording material from a fixing member in a fixing device, and the separation member is formed by fixing a molten fluororesin on the surface of a core material by molding. A recording material separating member for a fixing device, wherein the surface of the separating member is a fluororesin, and the separating member has no coating layer. 2. A recording material separating member for a fixing device according to claim 1, wherein a hole, a groove or an unevenness is formed for allowing the fluororesin melted into the core material to flow in, solidify and fix. 3. The recording material separating member for a fixing device according to claim 1, wherein the core material is made of a metal material. 3. The recording material separating member for a fixing device according to claim 1, wherein the core material is made of a plastic material. 3. The recording material separating member for a fixing device according to claim 1, wherein the core material is made of a glass material. The core material, a recording material separating member fixing device according to claim 1 or claim 2, wherein the thickness of the side separating the recording material is of formed shape thinner. 2. The fluororesin is a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer or tetrafluoroethylene-ethylene copolymer, A recording material separating member of the fixing device according to any one of -6.

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