Heater, fixing device, image forming apparatus, and heater device

Abstract

The invention provides a heater, a fixing device, an image forming apparatus, and a heating device. The heater can improve the heat generating performance of the boundary part of a plurality of heat generating units so as to improve the heat uniformity of the whole heater. The heater is characterized in that heating units divided by a boundary line are arranged on a base body, and the heater is provided with one resistance heating wire formed in each heating unit. Parallel wiring formed by a plurality of wires in parallel and folded wiring formed by folding the parallel wiring in the vicinity of a boundary line between a heat generating unit and an adjacent heat generating unit are connected together, and the whole heat generating unit has a meandering shape. The resistive heating wire of one heating unit has an extension portion formed so that the parallel wiring extends beyond the boundary line, and the resistive heating wire of the other heating unit is shortened or deformed so that the wiring at a location facing the extension portion is electrically insulated from the extension portion. The resistance heating wires of adjacent heating units are alternately provided with extension parts in the boundary line direction.

Description

Technical Field

[0001] The present invention relates to a heater, a fixing device, an image forming device, and a heating device. Specifically, the present invention relates to a heater having a plurality of heat generating units and having high thermal uniformity, and a fixing device, an image forming device, and a heating device having such a heater. Background Art

[0002] As a heating component for performing heat treatment on an object, a heater having a heating unit that generates heat when powered is provided on a substrate is known. Such a heater can be formed relatively thin and compact, and therefore, for example, is used for fixing purposes in copiers, printers, etc., or is incorporated into a dryer for heating and drying a processed object such as a panel. Among these uses, a heater that can connect a plurality of heating units in parallel and make the temperature distribution in the heating surface uniform is disclosed (for example, refer to Patent Documents 1 to 3).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: International Publication No. 2013 / 073276 Pamphlet

[0006] Patent Document 2: International Publication No. 2017 / 090692 Pamphlet

[0007] Patent Document 3: International Publication No. 2019 / 112058 Pamphlet Summary of the invention

[0008] Problem that the invention aims to solve

[0009] A heater for heating an object to be heated in a state facing a substrate is known. For example, a heater is disclosed in which a plurality of heating units are provided on a substrate, and a meandering resistance heating wire is formed in each heating unit (for example, refer to Patent Document 1). In this heater, a resistance heating material having a positive temperature coefficient of resistance is used, and each heating unit is connected in parallel, so that the temperature can be self-heated to each other, and a heater with uniform heating in the longitudinal direction can be obtained. In addition, excessive temperature rise of a specific heating unit can be prevented.

[0010] In addition, in the application of scanning the heated object relative to the substrate, such as Fig.16 As shown, the non-formed portion I of the resistance heating wire 30 which serves as a gap between the heating units of the heater described in patent document 1 is inclined relative to the length direction of the heater, thereby alleviating the effect of the heat reduction caused by the non-formed portion I of the resistance heating wire 30 in the scanning direction W.

[0011] However, recently, the uniformity of heat between adjacent heating units is being required at a very high level. In addition, a heater with an extremely narrow width in the scanning direction is desired. Therefore, even if the heater disclosed in Patent Document 1 is simply shortened in a manner that makes it narrower in the scanning direction, it becomes difficult to fully alleviate the influence of the heat reduction caused by the non-formed portion in the scanning direction.

[0012] Therefore, the inventors of the present application proposed a heater that disperses the gaps between the heating units by staggering the patterns of the resistance heating wires of adjacent heating units (Patent Document 2). In addition, a heater that can fill the thermal gaps generated between the heating units by setting the winding-shaped folding portion as a pattern connecting the horizontal wiring and the oblique wiring is proposed (Patent Document 3). Thus, even a heater with a narrow width in the scanning direction can achieve excellent thermal uniformity. However, there are heaters that are difficult to adopt these structures, and higher thermal uniformity is required. Therefore, there is a need for a heater that can be applied to more diverse forms to improve the thermal uniformity between multiple heating units. In addition, it is also strongly desired to achieve uniform heating when the temperature reaches a usable temperature after the heater is powered on, that is, rapid uniform heating after power is turned on.

[0013] The present invention is made in view of the above problems, and aims to provide a heater which improves the heat generation performance of the boundaries between a plurality of heat generating units and improves the heat uniformity of the heater as a whole. In addition, it aims to provide a fixing device, an image forming device and a heating device having such a heater.

[0014] Solutions for solving problems

[0015] The present invention is as follows.

[0016] 1. A heater, wherein a plurality of heating units are arranged on a substrate and separated by an imaginary dividing line, and heats an object to be heated facing the substrate, wherein:

[0017] The heater comprises:

[0018] the substrate; and

[0019] A resistance heating wire is formed in each of the heating units, and the resistance heating wire is formed by connecting a parallel wiring formed by a plurality of wirings in parallel and a folded wiring formed by folding the parallel wiring near the boundary between the heating unit and the adjacent heating unit, and the whole is in a meandering shape.

[0020] In the adjacent heating units, the resistance heating wire of one of the heating units has an extension portion formed in such a manner that the parallel wiring extends beyond the dividing line, and the resistance heating wire of the other heating unit is shortened or deformed in such a manner that electrical insulation is ensured between the wiring at a portion opposite to the extension portion and the extension portion.

[0021] The resistance heating wires of the adjacent heating units include the extending portions alternately in the boundary direction.

[0022] 2. The heater according to 1. above, wherein the extending portion of the resistance heating wire sandwiches the boundary line, and the entire or a part of the extending portion is arranged to be inclined at a predetermined angle relative to the boundary line.

[0023] 3. The heater according to 1. or 2., wherein the resistance heating wire has a bend in the parallel wiring.

[0024] The bent portion is formed in a convex shape toward a gap between the resistance heating wires of the adjacent heating units.

[0025] 4. The heater according to 1. or 2., wherein the plurality of heat generating units are arranged in a straight line.

[0026] 5. The heater according to 4., wherein the boundary line between the adjacent heating units is inclined at a predetermined angle with respect to the one straight line.

[0027] 6. The heater according to 4., wherein the resistance heating wire has a bent portion in the parallel wiring.

[0028] The bent portion is formed in a convex shape toward a gap between the resistance heating wires of the adjacent heating units.

[0029] 7. The heater according to 4. above, wherein the folded-back wiring is formed substantially parallel to the boundary line between the adjacent heat generating units.

[0030] For reference, in the heater described in 4. above, the resistance heating wires of the respective heating units may be respectively supplied with electricity.

[0031] 8. The heater according to 4. above, wherein the object to be heated is heated by scanning the base and the object to be heated relative to each other in a direction perpendicular to the one straight line.

[0032] 9. The heater according to 1. or 2., wherein the plurality of heat generating units are arranged in a circumferential direction of a circle.

[0033] 10. The heater according to 9. above, wherein the boundary line between adjacent heating units divides the circle into equal angles around the center.

[0034] 11. The heater according to 9. above, wherein the boundary line between the adjacent heat generating units is inclined at a predetermined angle with respect to a line segment that divides the circle equiangularly about the center.

[0035] For reference, in the heater described in 9., it can be set that the resistance heating wire has a bent portion in the parallel wiring,

[0036] The bent portion is formed in a convex shape toward a gap between the resistance heating wires of the adjacent heating units.

[0037] In addition, in the heater described in 9. above, the return wiring may be formed substantially in parallel with the boundary line between adjacent heat generating units.

[0038] In addition, in the heater described in 9. above, the turned-back wiring may be formed in the circumferential direction of the one circle at an upper end portion or a lower end portion in the boundary direction.

[0039] In addition, in the heater described in 9. above, the resistance heating wire of each of the heating units may be supplied with electricity separately.

[0040] 12. A fixing device, comprising the heater according to any one of 1. to 11.

[0041] 13. An image forming apparatus, the gist of which is to include the heater according to any one of 1. to 11.

[0042] 14. A heating device, comprising the heater according to any one of 1. to 11.

[0043] Effects of the Invention

[0044] According to the heater of the present invention, a plurality of heating units divided by an imaginary dividing line are arranged on a substrate to heat an object to be heated in a state facing the substrate. The heater comprises: the substrate; and a resistance heating wire formed in each of the heating units, the resistance heating wire being formed by connecting a parallel wiring formed by a plurality of wirings in parallel and a folded wiring formed by folding the parallel wiring near the dividing line between the heating unit and the adjacent heating unit, and the overall shape is a serpentine shape. In the adjacent heating units, one The resistance heating wire of one of the heating units has an extension portion formed in such a manner that the parallel wiring extends beyond the boundary line, and the resistance heating wire of another heating unit is shortened or deformed in such a manner that electrical insulation is ensured between the wiring at a portion opposite to the extension portion and the extension portion, and the resistance heating wires of adjacent heating units are alternately provided with the extension portions in the direction of the boundary line. Therefore, the heat generation of the boundary area is greatly improved by the resistance heating wires interlaced across the boundary line between adjacent heating units, and extremely high thermal uniformity of the heater as a whole can be obtained. In addition, the thermal uniformity is improved when the heater reaches a usable temperature after power is turned on. That is, the heat generation of the boundary area between the heating units can be improved, so that the temperature of the boundary portion rises rapidly after power is turned on, and a high uniformity heating performance can be exerted from the time the heater starts to work.

[0045] When the extension portion of the resistance heating wire clamps the dividing line and is entirely or partially inclined at a predetermined angle relative to the dividing line, the inclined extension portion can be used to further stagger the resistance heating wires with adjacent heating units, thereby expanding the heating range in the boundary area and effectively preventing the temperature from dropping.

[0046] When the resistance heating wire has a bending portion in the parallel wiring, and the bending portion is convex toward the gap between the resistance heating wires of the adjacent heating units, the resistance heating wire is formed in a manner that utilizes the bending portion to fill the gap between the wirings of the adjacent heating units, thereby further improving the uniformity of heat generation in the boundary area.

[0047] When the plurality of heat generating units are arranged in a straight line, a heater having a heat generating portion which is long in one direction and has high thermal uniformity over the entire length can be formed.

[0048] When the boundary line between adjacent heating units is inclined at a predetermined angle relative to the straight line, the non-heating parts between adjacent heating units can be arranged not in a direction perpendicular to the straight line, and in particular, when the heater and the heated object move relative to each other in the vertical direction, uniform heating can be applied to the heated object.

[0049] When the resistance heating wire has a bending portion in the parallel wiring, and the bending portion is convex toward the gap between the resistance heating wires of the adjacent heating units, the resistance heating wire is formed in a manner that utilizes the bending portion to fill the gap between the wirings of the adjacent heating units, thereby further improving the uniformity of heat generation in the boundary area.

[0050] Furthermore, when the turned-back wiring is formed substantially parallel to the boundary line between the adjacent heat generating units, the wiring of the extended portion and the wiring of the portion facing the wiring of the extended portion can be appropriately connected.

[0051] When the turned-back wiring is formed parallel to the one straight line at the upper end or the lower end in the boundary direction, the non-heat generating portion between adjacent heat generating units can be reduced at the end in the boundary direction.

[0052] In addition, when the resistance heating wires of each heating unit are powered separately, the heating of each heating unit can be controlled. In addition, if the resistance heating wires of multiple heating units are connected in parallel, the temperature of each heating unit can be uniform, and uniform heating performance can be obtained as a whole.

[0053] When the object to be heated is heated by scanning the base and the object to be heated relative to each other in a direction perpendicular to the straight line, the object long in the perpendicular direction can be heated by a heater narrow in the direction perpendicular to the straight line.

[0054] When the plurality of heat generating units are arranged in a circumferential direction of a circle, the plurality of heat generating units can be appropriately arranged on a disk-shaped substrate, and a heater having a heat generating portion with high thermal uniformity over the entire circumference can be constructed.

[0055] In addition, when the heat generating units are arranged in a circumferential direction of a circle, the same structure as the case where the heat generating units are arranged in a straight line can be applied to obtain the same effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a schematic plan view showing the basic structure of the heater.

[0057] Figure 2 This is a schematic plan view showing an example of a heater in which heat generating units are arranged in a straight line.

[0058] Figure 3 This is a schematic plan view showing an example of a heater in which heat generating units are arranged in a circle.

[0059] Figure 4This is a schematic plan view showing an example of a heater provided with two groups of heat generating units arranged in a circle.

[0060] Figure 5 It is a schematic plan view showing an example of wiring of resistance heating wires.

[0061] Figure 6 It is a plan view for explaining the non-wiring area between adjacent heat generating units.

[0062] Figure 7 It is a schematic plan view showing another wiring example of the resistance heating wire.

[0063] Figure 8 It is a schematic plan view showing another wiring example of the resistance heating wire.

[0064] Fig. 9 It is a schematic plan view showing a modified example of wiring of the resistance heating wire.

[0065] Fig.10 It is a schematic plan view showing another modified example of wiring of the resistance heating wire.

[0066] Fig.11 This is a graph showing an example of the temperature distribution of the heater immediately after the power is turned on.

[0067] Fig.12 This is a graph showing an example of temperature distribution when the heater is in use.

[0068] Fig.13 This is a schematic perspective view showing an example of a fixing device using a heater.

[0069] Fig.14 This is a schematic perspective view showing another example of a fixing device using a heater.

[0070] Fig.15 This is a schematic diagram showing an example of an image forming apparatus using a heater.

[0071] Fig.16 This is a plan view for explaining a non-wiring area between adjacent heat generating units in a conventional heater. DETAILED DESCRIPTION

[0072] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

[0073] 1. Heater

[0074] The heater (1) of this embodiment is a heater in which a plurality of heating units (C) divided by an imaginary dividing line (B) are arranged on a substrate (2) to heat an object to be heated facing the substrate (2). The heater (1) comprises a substrate (2) and a resistance heating wire (3) formed in each heating unit (C) (see Figure 1 , Figure 2 ).

[0075] In addition, one or more power supply wirings (F) for supplying power to each heating unit (C), power supply terminals for connecting to an external power source, temperature sensors, etc. can be arranged on the base (2). In addition, the heating unit itself can also be equipped with power supply wirings.

[0076] The heater (1) can heat the object by fixing the positional relationship between the heater and the object, or can heat the object by moving one or both of the heater and the object to be heated and scanning the object relatively.

[0077] (Matrix)

[0078] The base (2) is a substrate that supports a plurality of heating units (C). The surface shape of the base (2) is not particularly limited, and can be, for example, a rectangular shape (see Figure 2 ), round shape (refer to Figure 3 ), but not limited thereto, and any shape such as square, L-shaped, arc-shaped, and fan-shaped can be selected according to the purpose. In addition, the thickness of the substrate (2) can be determined according to its material, plane size, required strength, etc.

[0079] In the application of heating the object to be heated by scanning the object to be heated relative to the heater (1) in a scanning direction with the heating surface of the heater (1) facing the object to be heated, the cross-sectional shape of the substrate (2) in the scanning direction can be set to a circular arc shape convex to the side facing the object to be heated (i.e., a shape formed by cutting a cylinder or a cylinder with a plane parallel to the center axis) with the axis perpendicular to the scanning direction as the center. In this case, each resistive heating wire can be arranged on the convex surface, and each resistive heating wire can also be arranged on the opposite side (concave surface). By setting such a shape, the heater is mounted on a cylindrical roller, and the roller is rotated, so that the object to be heated scanned on the roller can be efficiently heated.

[0080] The material forming the substrate (2) is not limited, and for example, metal, ceramic, and composite materials thereof can be used.

[0081] As the metal forming the matrix (2), steel and the like can be cited, among which stainless steel can be appropriately used. The type of stainless steel is not particularly limited, and ferritic stainless steel and / or austenitic stainless steel are preferred. Among these stainless steels, those with excellent heat resistance and / or oxidation resistance are particularly preferred. For example, SUS430, SUS436, SUS444, SUS316L and the like can be cited. Of these stainless steels, only one can be used, or two or more can be used simultaneously.

[0082] In addition, aluminum, magnesium, copper, and alloys of these metals can be used as the metal forming the substrate (2). Only one of these metals can be used, or two or more of them can be used at the same time. Among them, aluminum, magnesium, and their alloys (aluminum alloy, magnesium alloy, Al-Mg alloy, etc.) have a relatively small specific gravity, so the heater can be made lighter by using them. In addition, copper and its alloys have excellent thermal conductivity, so the heat uniformity of the heater can be improved by using them.

[0083] When a conductive material such as metal is used as the material of the substrate (2), the substrate (2) is formed by providing an insulating layer on the conductive material in order to electrically insulate the conductive material from wiring (resistance heating wire, power supply wiring, power supply terminal, etc.) provided on the conductive material. In this case, the heating unit is formed on the insulating layer.

[0084] The material of the insulating layer is not particularly limited, for example, glass, ceramics, glass ceramics, etc. are preferred. Among these, when metal (stainless steel, etc.) is used as the material for forming the substrate (2), from the perspective of thermal expansion balance of the material of the insulating layer, the material of the insulating layer is preferably glass, and more preferably microcrystalline glass and semi-microcrystalline glass. Specifically, SiO2-Al2O3-MO glass is preferred. Among them, MO is an oxide of an alkaline earth metal (MgO, CaO, BaO, SrO, etc.). The thickness of the insulating layer is not particularly limited (for example, about 30 to 200 μm).

[0085] In addition, when ceramic is used to form the substrate (2), the material of the substrate can be a material that can achieve electrical insulation with the wiring (resistance heating wire, power supply wiring, power supply terminal, etc.) provided on the substrate. Preferred materials for the substrate include, for example, aluminum oxide, aluminum nitride, zirconium oxide, silicon dioxide, mullite, spinel, cordierite, silicon nitride, etc. Among these materials, only one may be used, or two or more may be used simultaneously. Among these materials, aluminum oxide and aluminum nitride are more preferred.

[0086] In addition, a composite material of metal and ceramic can also be used as the matrix (2). Preferred composite materials include SiC / C, SiC / Al, etc. These materials can be used alone or in combination of two or more.

[0087] (Heating unit)

[0088] A plurality of heating units (C) divided by an imaginary dividing line (B) are arranged on the substrate (2). The arrangement method of the heating units (C) is not limited, and as an example of a basic structure, a plurality of heating units (C) can be arranged in a straight line direction or in a circumferential direction of a circle (see Figure 2 , Figure 3 ). It is also possible to arrange a plurality of heating unit groups of such a basic structure on one substrate (2) (refer to Figure 4 ).

[0089] Adjacent heating units (C) are separated and electrically insulated by gaps. The boundary line (B) is a boundary line set in design to divide a plurality of heating units (C) (see Figure 1 , Figure 2 ). The dividing line (B) may be straight, curved or wavy.

[0090] The dividing line (B) can be set in a direction perpendicular to the arrangement direction of the plurality of heating units (C) (for example, the direction of the one straight line or the circumferential direction of the one circle). In addition, the dividing line (B) can also be set in a manner inclined relative to the arrangement direction of the plurality of heating units (C). For example, in the case where the heating unit groups are arranged in a straight line direction, the dividing line (B) can be set in a direction perpendicular to the one straight line direction, or can be set at a predetermined angle inclined relative to the one straight line. In addition, in the case where the heating unit groups are arranged in the circumferential direction of a circle, the dividing line (B) can be set in the radial direction of the one circle, or can be set at a predetermined angle inclined relative to the circumferential direction. The predetermined angle can be arbitrarily set according to the width of the heating unit (C) (the dimension in the direction perpendicular to the arrangement direction of the heating unit), etc. For example, it can be set to 15 degrees to 90 degrees (or 90 degrees to 165 degrees) relative to the arrangement direction of the heating unit, preferably to 25 degrees to 65 degrees (or 115 degrees to 155 degrees), and more preferably to 35 degrees to 55 degrees (or 125 degrees to 145 degrees).

[0091] When more than three heating units (C) are arranged, the inclination of the boundary line (B) of each heating unit relative to the arrangement direction of the heating units does not need to be the same angle, and can be inclined at different angles. For example, when four heating units (C1 to C4) are arranged, it can be configured as follows: the boundary line (B) between C1 and C2 is inclined 45 degrees relative to the arrangement direction of the heating units C1 to C4, the boundary line (B) between C2 and C3 is inclined 135 degrees relative to the arrangement direction of the heating units C1 to C4, and the boundary line (B) between C3 and C4 is inclined 45 degrees relative to the arrangement direction of the heating units C1 to C4.

[0092] (Resistance heating wire)

[0093] The heater (1) includes a resistance heating wire (3) formed in each heating unit (C), wherein the resistance heating wire (3) is formed by connecting a parallel wiring (L1) formed by a plurality of wirings in parallel and a folded wiring (L2) formed by folding the parallel wiring (L1) near a boundary (B) between the heating unit (C) and an adjacent heating unit, and the whole is in a meandering shape (see Figure 1 ).

[0094] For example, when three parallel wiring lines L1 are sequentially set as L 11 , L 12 , L 13 In the case of meandering, the meandering shape is achieved by folding back the wiring L2 at L 11 and L 12 Connect one end of each to L 11 and L 12 , Use the folded wiring L2 to 12 and L 13 The other end of each is connected to L 12 and L 13 In addition, when the four parallel wirings L1 are sequentially set as L 11 , L 12 , L 13 , L 14 In the case of L 11 and L 12 Connect one end of each to L 11 and L 12 , in L 12 and L 13 The other end of each is connected to L 12 and L 13 , in L 13 and L 14 Connect one end of each to L 13 and L 14 .

[0095] In the drawings, corners of portions where the wiring is bent, such as a connection portion between the parallel wiring and the turned-back wiring and an extension portion, are chamfered for depiction, but these corners do not need to be chamfered.

[0096] When a high TCR material (material with a high temperature coefficient of resistance) is selected as the wiring material of the resistive heating wire (3), the resistivity obtained by the material alone is low. Therefore, a serpentine shape formed by combining parallel wiring and folded wiring is used to make the wiring width thinner and the wiring length extended by multiples of the folding number to increase the resistance value, thereby achieving the heating value required for a practical heater.

[0097] In the meandering resistance heating wire (3), the film thickness and width of the wiring are preferably set to be substantially the same within one heating unit (C). In addition, they are preferably set to be substantially the same in different heating units (C). Of course, in each heating unit, the film thickness and wiring width can also be appropriately changed for the purpose of setting a temperature gradient, etc. as needed.

[0098] The wiring width and the distance between wirings (insulation distance) can be set to appropriate dimensions (for example, both are 0.1 mm to 3.5 mm, preferably 0.3 mm to 2.0 mm, and more preferably 0.4 mm to 1.2 mm).

[0099] The parallel wiring (L1) is a plurality of wiring portions in the resistance heating wire (3) that are arranged approximately in parallel. The parallel wiring (L1) is formed in a direction along the arrangement direction of the plurality of heating units (C), that is, in a direction intersecting the dividing line (B). For example, when the plurality of heating units (C) are arranged in a straight line direction, the parallel wiring (L1) is a plurality of wiring portions formed in a resistance heating wire in a direction approximately parallel to the straight line. In addition, when the plurality of heating units (C) are arranged in the circumferential direction of a circle, a plurality of wiring portions formed in approximately concentric circles in a resistance heating wire become parallel wiring (L1). In addition, when the resistance heating wire (3) is in an arc shape as a whole (including an elliptical arc shape), the parallel wiring (L1) can be set as a wiring portion arranged in a manner to form approximately concentric circles.

[0100] Moreover, the shape of the parallel wiring (L1) is not limited to a straight line or an arc, and can be a line with one or more bends, a winding curve, or other irregular straight lines or curves. As long as these multiple wirings are arranged roughly in parallel, they can be set as parallel wiring (L1).

[0101] A plurality of heating units (for example, heating units C1 and C2) are arranged in a row, and the parallel wirings L1 of the heating units are preferably overlapped with each other when the parallel wirings L1 are extended in the arrangement direction of the heating units C. That is, the parallel wirings L1 of the heating units C are preferably in the same straight line if they are linear parallel wirings L1, and are preferably on the circumference of the same circle if they are arc-shaped parallel wirings L1.

[0102] The folded wiring (L2) is a wiring portion that connects two adjacent parallel wirings (L1) in the resistance heating wire (3) in a manner that forms a folded shape as a portion of a meander by connecting the ends of two adjacent parallel wirings (L1). When the number of parallel wirings (L1) included in one heating unit C is n, the number of folded wirings L2 is usually n-1. When the heating unit is provided with a hole or other components, the number is not limited to this number.

[0103] The angle between the parallel wiring (L1) and the folded wiring (L2) is not limited. For example, the folded wiring (L2) can be formed substantially parallel to the boundary line (B) between adjacent heat generating units.

[0104] The inclination angle of the folded-back wiring (L2) is not particularly limited, and can be set to an angle substantially parallel to the boundary line (B) (see Figure 1 ). In addition, the plurality of return wirings (L2) of the resistance heating wire (3) of one heating unit (C) may have different inclination angles relative to the parallel wiring L1, and preferably have substantially the same inclination angles.

[0105] Preferably, the folded wiring (L2) is deformed or the inclination angle is changed in a manner such that the blank portion (non-heating portion) of the resistance heating wire (3) between adjacent heating units (C) is reduced at the upper end or lower end in the direction of the dividing line (B) of the heating unit (C). For example, when the heating units (C) are arranged side by side in a straight line direction, the folded wiring (L2) can be formed substantially parallel to the one straight line direction at the upper end or lower end in the direction of the dividing line (B).

[0106] As the material of the resistance heating wire (3) constituting the heating unit (C), a conductive material that can generate heat corresponding to the resistance value due to power supply can be used. The conductive material is not limited, and for example, silver, copper, gold, platinum, palladium, rhodium, tungsten, molybdenum, rhenium (Re) and ruthenium (Ru) can be used. Only one of these materials can be used, or two or more can be used at the same time. When two or more are used at the same time, an alloy can be used. More specifically, silver-palladium alloy, silver-platinum alloy, platinum-rhodium alloy, silver-ruthenium, silver, copper, gold, etc. can be used.

[0107] Each heating unit (C) can have any resistance heating characteristics, and preferably can play a self-temperature equalization effect (self-temperature compensation effect) between each heating unit. From this point of view, the conductive material forming the resistance heating wire (3) preferably has a positive resistance temperature coefficient. Specifically, the resistance temperature coefficient in the temperature range of -200°C to 1000°C is preferably 100ppm / °C to 4400ppm / °C, and more preferably 300ppm / °C to 3700ppm / °C, and particularly preferably 500ppm / °C to 3000ppm / °C. As such a material, silver alloys such as silver-palladium alloys can be cited.

[0108] When a plurality of resistance heating wires (i.e., heating units) formed using a conductive material having a positive temperature coefficient of resistance are connected in parallel, these plurality of heating units play a role of self-temperature balance with each other. That is, for example, in the case where the second heating unit is sandwiched by the first heating unit and the third heating unit, if the temperature of the second heating unit decreases, supplementary heat is provided from the first heating unit and the third heating unit. Due to the supplementary heat, the following effect is achieved: the current flowing to the first heating unit and the third heating unit whose temperatures have decreased is increased, so that the temperature decrease caused by the heat absorbed is restored autonomously. In other words, the heating units around the second heating unit operate in a manner that compensates for the temperature decrease of the second heating unit. In this way, the heater having a plurality of resistance heating wires formed using a conductive material having a positive temperature coefficient of resistance is autonomously controlled in a manner that generates heat uniformly over the range of the plurality of heating units.

[0109] Regarding the general metal material used for the resistance heating wire of the heater, for example, when silver (resistivity ρ = 1.62×10 -8 Ωm, temperature coefficient α=4.1×10 -3 / °C), the temperature coefficient α is large, but the resistivity ρ is small, so it is difficult to set a high resistance value. Therefore, palladium (ρ = 10.8 × 10 -8 Ωm, α=3.7×10 -3 / ℃), but even if the resistivity ρ increases, the temperature coefficient α will decrease. In this way, if a material with a high TCR characteristic is selected, there is a tendency for the resistivity to decrease. Therefore, in order to set the resistance heating wiring to a high TCR and practical resistance value, it is necessary to extend the wiring length. By adopting a meandering shape, the wiring length can be extended to increase the resistance value.

[0110] The resistance heating wires (3) of a plurality of heating units (C) connected to a pair of electrodes can be connected in parallel. The heating units connected in parallel can be controlled to generate heat in a unified manner. The electrical characteristics of the heating units connected in parallel are preferably substantially the same, such as resistance value and resistance heating characteristics.

[0111] (Extension)

[0112] The extension portion (31) is a portion formed by one or both of the parallel wiring and the folded wiring of the resistance heating wire (3) constituting a heating unit exceeding the boundary line (B). The resistance heating wire (3) of the heating unit adjacent to the heating unit has a portion (recessed portion) corresponding to the wiring pattern of the relative extension portion and shortening or deforming the wiring in a manner that ensures electrical insulation. In the adjacent heating unit (C), the resistance heating wire (3) is configured in a manner that alternately has extension portions (31) in the direction of the boundary line (B) (see Figure 1 ). Thus, the extension of one adjacent unit can be surrounded by the wiring of the other adjacent unit. In addition, the corresponding parallel wiring and return wiring of each extension (31) of the adjacent heating unit are usually arranged in parallel, but not limited to this.

[0113] In order to arrange and configure a plurality of heating units (C), it is necessary to form an insulating gap required for insulation between the heating units (C). The resistance heating wire (3) does not exist in the insulating gap, so a heating gap is generated. In particular, when the object to be heated is heated by scanning in a direction orthogonal to the arrangement direction of the heating units, the insulating gap is formed along the scanning direction, and a continuous heat gap is formed along the scanning direction during heating (see Fig.16 ).

[0114] Therefore, by alternately arranging the extensions (31) of the resistance heating wire (3) in the direction of the boundary (B) of adjacent heating units (C), the insulating gap does not form a straight line in the scanning direction, and the thermal blank portion can be dispersed in the direction orthogonal to the scanning. Although a thermal blank portion is generated between the extension of one side and the retreat of the other side of the adjacent heating units, the extension and the retreat are alternately arranged in the direction of the boundary, so that the thermal blank portion is dispersed.

[0115] The wiring pattern and length of the extension part (31) are not particularly limited. In addition, the wiring pattern of the setback part of the heating unit (C) arranged next to the extension part (31) is also not limited, and can be appropriately determined in a manner that reduces the gap between the wiring of the extension part of the heating unit on one side and ensures electrical insulation.

[0116] The extension part (31) can be arranged to be inclined at a predetermined angle relative to the boundary line (B). The part of the parallel wiring and / or the folded back wiring corresponding to the extension part (31) can be bent or inclined relative to each wiring outside the extension part. Alternatively, the extension part (31) can be formed to sandwich the boundary line (B), and all or part of it can be inclined at a predetermined angle relative to the boundary line (B). That is, the extension part (31) can also have a non-inclined part. For example, as an extension part, it can have an inclined part and a non-inclined part that is roughly parallel to the parallel wiring (L1).

[0117] By making the extension part (31) inclined relative to the boundary line (B), the extension part (31) extends deeper beyond the boundary line (B), and the resistance heating wires of adjacent heating units can be arranged in a pattern that intersects with each other at the boundary. Thus, the heating blank part can be reduced, and the temperature drop at the boundary can be greatly suppressed.

[0118] The inclination angle of the extension portion (31) with respect to the boundary line (B) can be appropriately selected (for example, 40 to 140 degrees, preferably 60 to 120 degrees, and more preferably 80 to 100 degrees).

[0119] (Bend)

[0120] In the heater (1), the resistance heating wire (3) has a bend (33) in the parallel wiring (L1), and the bend (33) can be formed into a convex shape toward the gap between the resistance heating wires (3) of the adjacent heating unit (C) (refer to Figure 1 ).

[0121] By providing the bent portion (33), the heat generation of a portion where the wiring density of the resistance heating wire is lower than that of other portions (for example, the gap between the extended portion of one heating unit and the retreated portion of the adjacent heating unit) can be increased.

[0122] The length of the bent portion (the length of the line segment connecting both ends thereof) and the protruding length of the convex shape are not particularly limited and may be appropriately selected so as to fill the gaps in the resistance heating wires.

[0123] Figure 1 and 2 The heater 1 is shown in which a plurality of heating cells C are arranged along a straight line (the longitudinal direction of the substrate 2) on a rectangular substrate 2 and are separated by a boundary line B. The boundary line B between adjacent heating cells C is inclined at a certain angle with respect to the straight line.

[0124] A resistance heating wire 3 is formed in each heating unit C. The resistance heating wire 3 is formed by connecting a parallel wiring L1 formed by a plurality of wirings in parallel and a folded wiring L2 formed by folding the parallel wiring L1 near a boundary line B between the heating unit C and an adjacent heating unit C, and the whole is in a meandering shape. In this example, the folded wiring L2 is formed substantially parallel to the boundary line B.

[0125] In the adjacent heating units C, the resistance heating wire 3 of one heating unit C has an extension portion 31 formed in such a manner that the parallel wiring L1 extends beyond the boundary line B, and the wiring of the resistance heating wire 3 of the other heating unit C has a retreat portion 32 shortened corresponding to the extension portion 31. The resistance heating wires 3 of the adjacent heating units are alternately provided with the extension portions 31 in the direction of the boundary line B. In addition, the extension portion 31 sandwiches the boundary line B, and is arranged at a certain angle relative to the boundary line B as a whole.

[0126] Furthermore, the resistance heating wire 3 has a bent portion 33 in the parallel wiring L1 , and the bent portion 33 is formed in a convex shape toward the gap between the resistance heating wires 3 of the adjacent heating cells C.

[0127] In the heater 1, the resistance heating wires 3 of the heating units C are connected in parallel by a pair of power supply wirings F. This is suitable for applications where the width of the substrate 2 is narrow and the substrate 2 and the object to be heated are heated by scanning the substrate 2 and the object to be heated relative to each other along the short side direction of the substrate 2. The extensions 31 are alternately arranged in the direction of the boundary line B, so that the thermal blank portions where the wiring of the resistance heating wires 3 does not exist between adjacent heating units are dispersed.

[0128] Figure 3 The heater 1 is shown in which a plurality of heating units C divided by a boundary line B are arranged along the circumference of a circle on a circular base 2. In this example, the boundary line B between adjacent heating units C is inclined at a certain angle relative to a line segment that divides the circle equiangularly about the center.

[0129] The resistance heating wire 3 of each heating unit C is formed by connecting a plurality of parallel wiring lines L1 arranged in parallel in a concentric circle shape and a return wiring line L2 formed by returning the parallel wiring line L1 near a boundary line B between the heating unit C and an adjacent heating unit C, and the whole is in a meandering shape.

[0130] In addition, the heater of this example is constructed in the same manner as the heater shown in the previous figure.

[0131] Figure 4 The example in which two groups of a plurality of heat generating units C arranged in a circumferential direction are provided on a circular base 2 is shown.

[0132] Figure 5The heater 1 is shown in which a plurality of heating units C are arranged along the long side of the rectangular substrate 2 and separated by a dividing line B. The dividing line B between adjacent heating units C is set in a direction perpendicular to the arrangement direction of the plurality of heating units C. Figure 1 The heater shown has the same structure.

[0133] Figure 6 This is a diagram for explaining the non-wiring portion I of the resistance heating wire 3 generated between adjacent heating units C. According to the wiring pattern of the resistance heating wire 3 of the present heater, the non-wiring portion I can be dispersed in the arrangement direction of the heating units C.

[0134] Figure 7 and Figure 8 The following are wiring examples showing the case where the number of parallel wiring lines L1 constituting the resistance heating wire 3 is 4 or 8. Figure 7 As shown, even in the case where the resistance heating wires 3 of adjacent heating units C cannot alternately have extension portions 31 in the direction of the boundary line B, the same effect can be obtained by deforming the wiring in a manner that minimizes the non-wiring portions between adjacent heating units C and disperses the non-wiring portions in the arrangement direction of the heating units C.

[0135] Fig. 9 and Fig.10 The figure shows a modified example of the wiring pattern of the resistance heating wire 3 between adjacent heating units C. In this way, the wiring pattern of the retreated portion 32 formed by the resistance heating wire 3 of one heating unit C can be arbitrarily changed according to the wiring pattern of the extended portion 31 formed by the resistance heating wire 3 of another heating unit C. As shown in the two figures, in the extended portion 31 and the retreated portion 32 of the adjacent heating units C, each folded wiring L2 can be set to an arbitrary inclination angle relative to the dividing line B. In addition, as shown in FIG. Fig.10 As shown, the extension portion 31 sandwiches the boundary line B, a part of which is inclined at a certain angle relative to the boundary line B, and the other part can be set in a direction parallel to the arrangement direction of the heating units C. In addition, the folded wiring L2 can also be set in a direction parallel to the arrangement direction of the heating units C, or can be set as a hairpin-shaped fold.

[0136] Fig.11 and Fig.12 The temperature distribution measured using a heater including seven heating elements C1 to C7 arranged in a straight line in the X direction is shown. Fig.11 This is the temperature distribution just after voltage is applied to the heater (about 12 seconds later). As an effect of the resistance heating line pattern with an extension between each heating unit, it can be seen that the temperature of the boundary of each heating unit quickly reaches the heater operating temperature after the power is turned on. In addition, Fig.12This is the temperature distribution when the temperature of the heater reaches the reference temperature after voltage is applied to the heater, and the heater as a whole has high thermal uniformity.

[0137] The heater (1) can be installed in image forming devices such as printers, copiers, fax machines, and fixing devices, and used as a fixing heater for fixing toner, ink, etc. to a recording medium. In addition, it can be installed in a heating machine and used as a heating device for uniformly heating (drying or firing, etc.) a processed body such as a panel. In addition, it can properly perform heat treatment of metal products, heat treatment of coatings and films formed on substrates of various shapes, etc. Specifically, it can be used for heat treatment of coatings (filter constituent materials) for flat panel displays, coating drying of metal products after coating, automobile-related products, woodworking products, etc., electrostatic hair grafting drying, heat treatment of plastic processing products, reflow soldering of printed circuit boards, printing drying of thick film integrated circuits, etc.

[0138] 2. Fixing device

[0139] The fixing device with this heater can be set to a structure appropriately selected according to the material, shape, fixing component, etc. of the heated object. For example, in the case of fixing toner and the like on a recording medium such as paper with a fixing component accompanied by pressure contact, or in the case of bonding multiple components, it can be set to a fixing device with a heating part and a pressure part, and the heating part has a heater. Of course, it can also be set to a fixing component without pressure contact. In the present invention, it is preferred to use a fixing device 5 that fixes an unfixed image containing toner formed on the surface of a recording medium such as paper or film to the recording medium.

[0140] Fig.13 1 shows the main part of the fixing device 5 provided in the electrophotographic image forming apparatus. The fixing device 5 includes a rotatable fixing roller 51 and a rotatable pressure roller 54, and the heater 1 is provided inside the fixing roller 51. The heater 1 is preferably provided close to the inner surface of the fixing roller 51.

[0141] For example, as shown in the figure, the fixing member 5 may be configured such that the heater 1 is fixed inside a heater holder 53 formed of a material capable of conducting the heat generated by the heater 1 , and the heat generated by the heater 1 is transferred from the inside to the outside of the fixing roller 51 .

[0142] Fig.14 The main part of the fixing device 5 provided in the image forming apparatus of the electrophotographic method is also shown. The fixing device 5 includes a rotatable fixing roller 51 and a rotatable pressing roller 54, and a heater 1 for transferring heat to the fixing roller 51 and a fixing pad 52 for pressing the recording medium together with the pressing roller 54 are provided inside the fixing roller 51. The heater 1 is provided along the cylindrical surface of the fixing roller 51.

[0143] In the fixing device 5 shown in the figure, a voltage is applied from a power supply device not shown in the figure, so that the heater 1 generates heat, and the heat is transferred to the fixing roller 51. Then, if a recording medium having an unfixed toner image on the surface is supplied between the fixing roller 51 and the pressure roller 54, the toner melts at the pressure contact portion between the fixing roller 51 and the pressure roller 54 to form a fixed image. Since there is a pressure contact portion between the fixing roller 51 and the pressure roller 54, they rotate together. As described above, the heater 1 can suppress the local temperature rise that is easy to occur when a small recording medium is used, so that temperature unevenness is not easy to occur in the fixing roller 51, and fixing can be performed uniformly. Moreover, even after the fixing device is just started to be used, the uniformity of the adjacent parts of the heating units of the heater 1 is excellent, so that a fixing result substantially the same as the fixing result when it is used continuously can be obtained.

[0144] As another embodiment of the fixing device including the present heater 1 , a mold including an upper mold and a lower mold, wherein a heater is disposed inside at least one of the upper mold and the lower mold, can be adopted.

[0145] The fixing device including the heater 1 is installed in household electrical appliances represented by image forming apparatuses such as electrophotographic printers and copiers, and precision equipment for business and experiments, and is suitable as a heat source for heating and heat preservation.

[0146] 3. Image forming device

[0147] The image forming apparatus equipped with the present heater can be set to a structure appropriately selected according to the object to be heated, the purpose of heating, etc. In the present invention, as shown in the figure, it is preferably an image forming apparatus 4 as follows, which includes: an imaging component for forming an unfixed image on the surface of a recording medium such as paper or film; and a fixing component 5 for fixing the unfixed image on the recording medium, and the fixing component 5 includes the present heater 1. In addition to the above components, the image forming apparatus 4 can also be configured to include a recording medium conveying component and a control component for controlling each component.

[0148] Fig.15 1 is a schematic diagram showing the main parts of an image forming apparatus 4 of an electrophotographic method. As an imaging component, it is also possible to use a method with a transfer roller or a method without a transfer roller. Fig.15 This is a form having a transfer roller.

[0149] In the imaging component, the laser output from the laser scanner 41 is irradiated onto the charged surface of the photosensitive drum 44 which is charged to a predetermined potential by the charging device 43 while rotating, and an electrostatic latent image is formed using the toner supplied from the developer 45. Next, the toner image is transferred to the surface of the transfer drum 46 which is linked to the photosensitive drum 44 by using the potential difference. Thereafter, the toner image is transferred to the surface of the recording medium supplied between the transfer drum 46 and the transfer roller 47, and a recording medium having an unfixed image is obtained. Toner is a particle containing a binder resin, a colorant, and an additive, and the melting temperature of the binder resin is generally 90°C to 250°C. In addition, a cleaning device for removing unwanted toner and the like can be provided on the surface of the photosensitive drum 44 and the transfer drum 46.

[0150] The fixing member 5 can be configured in the same manner as the fixing device 5, and includes a pressure roller 54 and a fixing roller 51. The fixing roller 51 includes a heater holder 53 that holds a heater 1 that is energized in the paper feeding direction and is linked to the pressure roller 54. A recording medium with an unfixed image from the imaging member is supplied between the fixing roller 51 and the pressure roller 54. The heat of the fixing roller 51 melts the toner image on the recording medium, and the melted toner is pressed by the pressure contact portion between the fixing roller 51 and the pressure roller 54, so that the toner image is fixed to the recording medium. In the fixing member 5 of FIG. 20, a fixing belt having a heater 1 disposed near the fixing roller 51 may be provided instead of the fixing roller 51.

[0151] Generally speaking, when the temperature of the fixing roller 51 becomes uneven and the heat applied to the toner is too small, the toner may peel off from the recording medium. On the other hand, when the heat is too large, the toner may adhere to the fixing roller 51 and adhere to the recording medium again after the fixing roller 51 rotates once. According to the fixing component 5 having the heater of the present invention, the predetermined temperature is quickly adjusted, so that the bad situation can be suppressed. In addition, even after the fixing device is just started to be used, the heat blanks of the adjacent parts of the heating units of the heater 1 are dispersed, so that the uniformity is excellent. Therefore, even if the recording medium is passed (scanned), it will not become an overheated or underheated part, and the fixing result substantially the same as the fixing result when it is used continuously can be obtained.

[0152] The image forming apparatus of the present invention suppresses excessive temperature rise in the non-paper feeding area during use, and is suitable as an electrophotographic printer, a copying machine, and the like.

[0153] 4. Heating device

[0154] The heating device equipped with the present heater can be set to a structure appropriately selected according to the size and shape of the object to be heated. In the present invention, for example, it can be composed of the following parts: a shell part; a window part, which can be sealed and is configured for the entry and exit of the heat-treated object; and a heater part, which can be moved and is arranged inside the shell part. As needed, the following parts can be arranged inside the shell part: a heat-treated object setting part, which is used to arrange the heat-treated object; an exhaust part, which exhausts the gas when the gas is exhausted by heating the heat-treated object; and a pressure adjustment part such as a vacuum pump, which is used to adjust the pressure inside the shell part. In addition, the heat-treated object and the heater part can be heated with the heat-treated object and the heater part fixed, or either of them can be moved for heating.

[0155] The heating device is suitable as a device for drying a heat-treated object containing water, an organic solvent, etc. at a desired temperature. In addition, it can be used as a vacuum dryer (reduced pressure dryer), a pressurized dryer, a dehumidifying dryer, a hot air dryer, an explosion-proof dryer, etc. In addition, it is suitable as a device for firing an unfired object such as an LCD panel, an organic EL panel, etc. at a desired temperature. In addition, it can be used as a reduced pressure firing machine, a pressurized firing machine, etc.

[0156] In addition, the present invention is not limited to the embodiments shown in the above-mentioned specific embodiments, and various modifications can be made within the scope of the present invention according to the purpose and application.

[0157] Description of Reference Numerals

[0158] 1. Heater; 2. Base; 3. Resistance heating wire; 31. Extension portion; 32. Recessed portion; 33. Bending portion; 4. Image forming device; 41. Laser scanner; 42. Mirror; 43. Charging device; 44. Photosensitive roller; 45. Developer; 46. Transfer roller; 47. Transfer roller; 5. Fixing device (fixing component); 51. Fixing roller; 52. Fixing pad; 53. Heater holder; 54. Pressurizing roller; B. Demarcation line; C. Heating unit; F. Power supply wiring; L1. Parallel wiring; L2. Folding wiring.

Claims

1. A heater, wherein a plurality of heating units are arranged on a substrate and separated by an imaginary dividing line, and heats an object to be heated facing the substrate, characterized in that: The heater comprises: the substrate; and A resistance heating wire is formed in each of the heating units, and the resistance heating wire is formed by connecting a parallel wiring formed by a plurality of wirings in parallel and a folded wiring formed by folding the parallel wiring near the boundary between the heating unit and the adjacent heating unit, and the whole is in a meandering shape. In the adjacent heating units, the resistance heating wire of one of the heating units has an extension portion formed in such a manner that the parallel wiring extends beyond the dividing line, and the resistance heating wire of the other heating unit is shortened or deformed in such a manner that electrical insulation is ensured between the wiring at a portion opposite to the extension portion and the extension portion. The resistance heating wires of the adjacent heating units include the extending portions alternately in the boundary direction.

2. The heater according to claim 1, wherein The extending portion of the resistance heating wire sandwiches the boundary line, and is entirely or partially disposed to be inclined at a predetermined angle relative to the boundary line.

3. The heater according to claim 1 or 2, wherein: The resistance heating wire has a bent portion in the parallel wiring. The bent portion is formed in a convex shape toward a gap between the resistance heating wires of the adjacent heating units.

4. The heater according to claim 1 or 2, wherein: The plurality of heating units are arranged in a straight line.

5. The heater according to claim 4, wherein The boundary line between the adjacent heating units is inclined at a predetermined angle with respect to the one straight line.

6. The heater according to claim 4, wherein The resistance heating wire has a bent portion in the parallel wiring. The bent portion is formed in a convex shape toward a gap between the resistance heating wires of the adjacent heating units.

7. The heater according to claim 4, wherein: The turned-back wiring is formed parallel to the one straight line at an upper end or a lower end in the boundary line direction.

8. The heater according to claim 4, wherein The object to be heated is heated by scanning the base and the object to be heated relative to each other in a direction perpendicular to the one straight line.

9. The heater according to claim 1 or 2, wherein: The plurality of heat generating units are arranged in a circumferential direction of a circle.

10. The heater according to claim 9, wherein The boundary line between adjacent heating units divides the circle into equal angles around the center.

11. The heater according to claim 9, wherein The boundary line between the adjacent heating units is inclined at a predetermined angle with respect to a line segment that divides the circle equiangularly about the center.

12. A fixing device, characterized in that: The fixing device includes the heater according to any one of claims 1 to 11.

13. An image forming device, characterized in that: The image forming apparatus includes the heater according to any one of claims 1 to 11.

14. A heating device, characterized in that: The heating device includes the heater according to any one of claims 1 to 11.

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