JPH01116584A - Production of heat fixing roll for copying machine - Google Patents

Abstract

PURPOSE:To obtain a high-performance heat fixing roll of a low cost by forming a reinforcing insulation layer on the inside surface of the groove in the trace after a masking material is removed, then subjecting a yarn-like antistick material to painting in the stable of winding said material in the spiral recess formed on the surface at this time. CONSTITUTION:A thin film-like insulation layer 2 is formed by plasma thermal spraying of alumina, etc., on the surface of a hollow metallic pipe 1 and a metallic wire 3 is spirally wound thereon from the outside thereof. For example, nichrome, alumina-nickel mixture or the like is thermally sprayed on the form of a thin film by a thermal spraying torch 4a between the spiral pitches thereof to form a heating resistor layer 4. The metallic wire 3 is then removed to form the groove in the trace after the removal and the reinforcing insulation layer 6 is formed on the inside surface of the groove. The yarn-like antistick material 8 is wound in the spiral recess 7 formed at this time and is painted thereon with, for example, a PFA resin or the like, by a powder painting method to form an antistick layer 9. A slight projection 10 formed on the outside of the yarn-like antistick material 8 is polished and smoothed. The direct heat type fixing roll is thereby obtd. at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method of manufacturing a heat fixing roll for an electronic copying machine.

2. Description of the Related Art Conventionally, this type of heat fixing roll was manufactured by winding metal wires in a spiral shape on the outside of a hollow tube through an insulating layer, and then melting a heat generating resistor onto the surface of the metal wires to form a heat generating resistor layer. After forming the
The metal wire is removed and a spiral groove is formed therein, and an insulating layer and an anti-adhesion layer are formed on the surface of the heating resistor and within the groove, and at this time, an insulating layer and an anti-adhesion layer are inevitably formed on the surface of the anti-adhesion layer. In order to eliminate the spiral depressions, the surface of the anti-adhesion layer was polished until it became smooth over its entire length.

In this case, since the width of the spiral heating element layer is significantly larger than the width of the groove, for example, the former is 3 to 10 Tt1 m while the latter is 0.5 mm, so the amount of polishing of the anti-adhesion layer is significantly large. . Therefore, expensive adhesion prevention resin is wasted.

Problems to be Solved by the Invention An object of the present invention is to minimize the amount of expensive resin consumed when polishing the surface of the anti-adhesion layer in the conventional method, or to enable use without polishing. An object of the present invention is to provide a heat fixing roll.

Means for solving the problem: An insulating layer is formed on the surface of a metal hollow tube, a metal wire is wound spirally on it for masking, and a heating resistor layer is placed on the exposed surface of the insulating layer. is formed by thermal spraying with the spiral top slightly protruding, then a spiral groove is formed in the area where the metal wire is removed, and the inner surface of the groove and the entire surface of the heating resistor layer are coated with ceramic. Covering with an insulating layer, at this time wrapping a filamentous adhesion prevention material in the spiral depression formed on the surface of the ceramic insulating layer, and further coating the surfaces of the insulating layer and the filamentous adhesion prevention material with an f1 adhesion prevention layer, Thereafter, the surface of this anti-adhesion layer is polished to make it smooth, if necessary.

In order to separate and form the heat generating resistor layer for the heat generating resistor to a predetermined width, a metal wire is spirally wound around the outside of the hollow tube through an insulating layer to form a masking member. A layer was formed by thermal spraying, a reinforcing insulating layer was formed on the inner surface of the groove left after the masking material was removed, and a thread-like anti-adhesion material was wrapped in the spiral depression formed on the surface at that time. Since the anti-adhesion material is applied over the surface of the anti-adhesion layer, there is no depression at the position where the masking material is removed on the surface of the anti-adhesion layer, and the surface of the anti-adhesion layer has excellent flatness. It can be made extremely thin, there is no need for polishing in some cases, the loss of the expensive resin for the adhesion prevention layer can be minimized, and a low-cost, high-performance heat fixing roll can be obtained.

Embodiment The present invention will be explained with reference to FIGS. 1 to 9 of the attached drawings. Alumina, magnesia alumina spinel, etc. are plasma sprayed on the surface of a metal hollow tube 1 to form a thin film-like insulating layer, for example, about 200 μm thick. 2, a metal wire 3 is wound spirally from the outside, and in this state, the surface of the insulating layer 2 between the spiral pitches is coated with, for example, nichrome, stainless steel, aluminum, aluminum wax, titanya-chromya mixture, titania.・Nichrome mixture, silica, alumina, nickel mixture, etc. in the form of a thin film, for example, with a thickness of about 30 to 1
The heating resistor layer 4 is formed by thermal spraying to a thickness of approximately 0.00 μm using a thermal spraying torch 4a.

At this time, the top portion 3a of the metal wire 3 protrudes from the surface of the heating resistor 4. This condition is shown on the left side of FIG. 3 and in FIG. 4.

Next, after removing the metal wire 3 and forming a groove 5 in its trace as shown in FIG. 5, a reinforcing insulating layer 6 is formed on the surface of the heating resistor layer 4 and the inner surface of the groove 5 as shown in FIG. . In this case, the reinforcing insulating layer 6 is made of a ceramic material such as alumina or magnesia alumina spinel by plasma spraying or the like, with a thickness of 100 to 250 μm, and as shown in FIG. As shown in FIG. 7, thread-like anti-adhesion material 8 made of PFA monofilament or the like with a thickness of 50 to 200 μm is wrapped around the spiral depression 7 that is inevitably formed at the position of the groove on the surface of the layer. For example, a PFA resin or the like is applied from above using a method such as powder coating to form an anti-adhesion layer 9 as shown in FIG. Polish it to make it smooth as shown in Figure 9.

The fixing roll obtained in this way as shown in FIG. 9 can be used immediately without polishing depending on the purpose of use, or even if it is used after polishing, compared to the conventional method described above. Only one polishing step is required, making it possible to manufacture a direct heating type fixing roll at an extremely low cost.

The material of the anti-adhesion layer is not limited to fluororesins such as PFA, but silicone-based and other resins with excellent anti-adhesion properties can also be used, and the method of application is not limited to powder coating. Other than that, well-known liquid coating etc. can be applied.

The material of the filamentous adhesion prevention material 8 is not limited to PFA monofilament, but mainly thermoplastic resins can be selected and used depending on the conditions of use, and yarn may provide better results in some cases. Generally, resins with higher melting points have better work flexibility.

Although the present invention has been described above with reference to the embodiments shown in FIGS. 1 to 9, the present invention is not limited thereto. For example, the metal wire 3 is shown in FIGS. 1 and 3 as in the same embodiment. When winding it spirally, it is wound in a double spiral as shown in FIG. The direction of the current flowing through the adjacent heating resistor layers 4 is
Within the scope of the gist of the present invention, some portions may be slightly modified and implemented, such as when they are oriented in opposite directions.

In contrast, in the conventional method, as shown in FIG. 12, an insulating layer 12 is formed on the surface of a hollow tube 11, and a metal wire (not shown) is wound spirally on the insulating layer 12. A heat generating resistor layer 14 is formed on them as a masking material, the metal wire is removed, a reinforcing insulating layer 15 is formed by thermal spraying on the remaining edge and the heat generating resistor layer, and furthermore, by painting. An anti-adhesion layer 16 made of fluororesin or the like was formed, and then the anti-adhesion layer 16 was polished to the level of the smooth surface 17 shown in FIG. 13. At that time, as shown in FIG.
A spiral thread 16a is inevitably formed on the surface of the adhesion prevention layer 16, and the width d of the other portion is much larger than the width C of the single thread 16a. When polishing, the amount of polishing of the anti-adhesion layer 16 increases. This is because the metal wire does not adhere closely to the insulating layer 12, so in order to obtain a reliable masking effect, a thickness of 350 to 700 μm is required.
If the width of the groove is between 400 and 75,
Even if an anti-adhesive layer or a reinforcing insulating layer is formed with the thickness required for strength, durability, and anti-adhesion purposes, there will be one strip on the roll surface before polishing. This is because 16a is inevitably formed.

Effects Since this invention is as described above, the amount of polishing of the anti-adhesion layer when polishing the surface of the anti-adhesion layer can be extremely reduced compared to the conventional method, and in some cases, no polishing is required. You can also get a finished product.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway front view showing the state in which the filament prevention material is wrapped around the surface of the insulating layer, Figure 2 is an enlarged cross-sectional view of a portion of Figure 1, and Figure 3 is the thermal spraying of the heating resistor layer. The front view of the die, Figure 4 is 3rd Uf! An enlarged sectional view of a part of U, Fig. 5 is a sectional view of the heating resistor layer with grooves formed, Fig. 6 is a sectional view of the reinforcing insulating layer after processing, and Fig. 7 shows the filamentous adhesion prevention material. A cross-sectional view after wrapping, FIG. 8 is a cross-sectional view after the processing of the anti-adhesion layer is completed, FIG. 9 is a cross-sectional view after the polishing of the anti-adhesion layer is completed, and FIG. 10 is another example. FIG. 11 is a front view of another state of FIG. 10, FIG. 12 is an enlarged sectional view of a part in the conventional manufacturing method, and FIG. 13 is a sectional view showing the state of the pond in the middle. be. 1...Hollow tube 2...Insulating layer 3...Metal wire 4...Heating resistor layer 5...Way 6...Reinforcement insulating layer 7...Indentation 8...Thread-like adhesion prevention material 9...Adhesion prevention layer 10... protrusion

Claims (1)

[Claims] 1. An insulating layer is formed on the outside of the hollow tube, a metal wire is wound spirally on the insulating layer for masking, a heating resistor layer is formed by spraying on the exposed surface of the insulating layer, and the metal The wire is removed, a spiral groove is formed in its trace, the surface of the heating resistor layer and the inner surface of the spiral groove are covered with a ceramic insulating layer to form a reinforcing insulating layer, and the surface of the reinforcing insulating layer is covered with a ceramic insulating layer. A method for manufacturing a heat fixing roll for a copying machine, comprising the steps of: wrapping a filamentous anti-adhesion material in the spiral depressions to be formed, and then covering a reinforcing insulating layer and the filamentous anti-adhesion material with an anti-adhesion layer.