JP2022121832A - Heater, and image forming apparatus - Google Patents

Abstract

To provide a heater and an image forming apparatus that can improve a dielectric strength even when a plurality of heating elements arranged side by side along a pair of wiring are provided.SOLUTION: A heater according to an embodiment is provided with: a substrate that exhibits a plate shape and extends in a first direction; first wiring that is provided on one face of the substrate and extends in the first direction; second wiring that is provided on one face of the substrate, is separated from the first wiring in a second direction orthogonal to the first direction, and extends in the first direction; and a plurality of heating elements that are provided between the first wiring and the second wiring and arranged side by side in the first direction. When seen from a direction perpendicular to one face of the substrate, the angles of sides of the plurality of heating elements connected with the first wiring are all obtuse angles or right angles, or the contours of ends connected with the first wiring are formed of curves. The angles of sides of the plurality of heating elements connected with the second wiring are all obtuse angles or right angles, or the contours of ends connected with the second wiring are formed of curves.SELECTED DRAWING: Figure 4

Description

Embodiments of the present invention relate to heaters and image forming apparatuses.

2. Description of the Related Art Image forming apparatuses such as copiers and printers are provided with heaters for fixing toner. Generally, such a heater includes an elongated substrate, a heating element provided on one surface of the substrate, and wiring electrically connected to the heating element.

Also proposed is a heater having a pair of wires extending along the long side of the substrate and a plurality of heating elements provided between the pair of wires and arranged along the pair of wires. One end of each of the plurality of heating elements is electrically connected to one wiring. The other ends of the multiple heating elements are electrically connected to the other wiring. If such a heating element is provided, it is possible to suppress the occurrence of temperature distribution in the heater (substrate).

However, simply providing a plurality of heating elements arranged along a pair of wires poses a problem that, for example, dielectric strength against surge voltage (for example, lightning surge) from the outside decreases.

Therefore, it has been desired to develop a technique that can improve the dielectric strength even when a plurality of heating elements are arranged along a pair of wires.

JP 2014-134819 A

SUMMARY OF THE INVENTION An object of the present invention is to provide a heater and an image forming apparatus capable of improving dielectric strength even when a plurality of heating elements are arranged along a pair of wirings. .

A heater according to an embodiment has a plate shape and extends in a first direction; a first wiring provided on one surface of the substrate and extending in the first direction; and one surface of the substrate. a second wiring provided in and separated from the first wiring in a second direction orthogonal to the first direction and extending in the first direction; the first wiring and the second wiring; and a plurality of heating elements provided between wirings and arranged in the first direction. When viewed from a direction perpendicular to one surface of the substrate, all of the plurality of heating elements have obtuse angles or right angles on the side connected to the first wiring, or are connected to the first wiring. The contour of the edge on the side to be drawn is composed of curved lines. The angles of the plurality of heating elements on the side connected to the second wiring are all obtuse angles or right angles, or the contours of the ends on the side connected to the second wiring are composed of curved lines.

According to the embodiments of the present invention, it is possible to provide a heater and an image forming apparatus capable of improving dielectric strength even when a plurality of heating elements are provided along a pair of wirings.

FIG. 4 is a schematic plan view of the heater according to the present embodiment viewed from the side on which the heat generating portion is provided; FIG. 2 is a schematic cross-sectional view of the heater in the direction of line AA in FIG. 1; (a) is a schematic plan view for illustrating a planar shape of a heating element according to a comparative example. (b) and (c) are schematic enlarged plan views of a heating element. (a) is a schematic plan view for illustrating the planar shape of a heating element according to the present embodiment. (b) and (c) are schematic enlarged plan views of a heating element. (a) is a schematic plan view for illustrating the planar shape of a heating element according to another embodiment. (b) and (c) are schematic enlarged plan views of a heating element. 4 is a table for illustrating the relationship between the ratio of ruthenium oxide contained in a heating element, the dielectric strength, and the amount of heat generated by wiring. 1 is a schematic diagram illustrating an image forming apparatus according to an exemplary embodiment; FIG. 4 is a schematic diagram for illustrating a fixing section; FIG.

Hereinafter, embodiments will be illustrated with reference to the drawings. In addition, in each drawing, the same reference numerals are given to the same constituent elements, and detailed description thereof will be omitted as appropriate.
Arrows X, Y, and Z in each drawing represent three directions orthogonal to each other. For example, the longitudinal direction of the substrate is the X direction (corresponding to an example of the first direction), the lateral direction (width direction) of the substrate is the Y direction (corresponding to an example of the second direction), and the direction is perpendicular to the surface of the substrate. direction (thickness direction) is the Z direction.

First, the heater 1 according to this embodiment will be described.
(heater)
FIG. 1 is a schematic plan view of the heater 1 according to the present embodiment, viewed from the side where the heat generating portion 20 is provided.
FIG. 2 is a schematic cross-sectional view of the heater 1 in FIG. 1 taken along line AA.
As shown in FIGS. 1 and 2, the heater 1 has, for example, a substrate 10, a heating portion 20, a wiring portion 31, a wiring portion 32, and a protective film 40. FIG.

The substrate 10 has a plate-like shape and extends in one direction (for example, the X direction). The planar shape of the substrate 10 can be, for example, an elongated rectangle. The thickness of the substrate 10 can be, for example, approximately 0.5 mm to 1.0 mm. The planar dimension of the substrate 10 can be appropriately changed according to the size of the object to be heated (for example, paper).

The substrate 10 is made of a heat-resistant and insulating material. The substrate 10 can be formed of, for example, ceramics such as aluminum oxide or aluminum nitride, crystallized glass (glass ceramics), or a metal plate whose surface is coated with an insulating material.

The heat generating part 20 converts the applied electric power into heat (Joule heat). The heat generating portion 20 is provided on one surface of the substrate 10 .
The heating unit 20 has, for example, a plurality of heating elements 21 and a plurality of heating elements 22 . The plurality of heating elements 21 are provided between, for example, a wiring 31a (corresponding to an example of first wiring) and a wiring 32a (corresponding to an example of second wiring) and arranged in the X direction. . The plurality of heating elements 22 are arranged in the X direction, for example, between the wiring 31b (corresponding to an example of the first wiring) and the wiring 32a. A row of the plurality of heating elements 21 and a row of the plurality of heating elements 22 are arranged in the Y direction.

As an example, the plurality of heat generating elements 21 arranged in a line and the plurality of heat generating elements 22 arranged in a line are illustrated, but either the plurality of heat generating elements 21 or the plurality of heat generating elements 22 are provided. may be made available. Also, the plurality of heat generating elements arranged in the X direction may be arranged in three or more rows in the Y direction. The number of heating elements, planar dimensions, thickness, arrangement, etc. can be appropriately changed according to the size of the object to be heated. Further, it is possible to provide heating elements with different planar dimensions and thicknesses, or to provide heating elements with at least one of the same planar dimensions and thickness.

The plurality of heating elements 21 and the plurality of heating elements 22 are film-shaped. The thickness of the plurality of heating elements 21 and the plurality of heating elements 22 can be, for example, 15 μm to 20 μm. The width of the plurality of heat generating elements 21 and the plurality of heat generating elements 22 (the dimension in the direction perpendicular to the direction in which the heat generating elements extend) can be, for example, 0.5 mm to 1.0 mm.

The plurality of heating elements 21 and the plurality of heating elements 22 contain at least ruthenium oxide (RuO ₂ ). For example, the plurality of heating elements 21 and the plurality of heating elements 22 contain ruthenium oxide and copper oxide.
The details of the proportion of ruthenium oxide will be described later.

The plurality of heat generating elements 21 and the plurality of heat generating elements 22 are formed by, for example, applying a paste material to the surface of the substrate 10 using a screen printing method or the like, and curing the paste material using a baking method or the like. can be formed with

The wiring portion 31 and the wiring portion 32 are provided on the surface of the substrate 10 on which the heat generating portion 20 is provided.

The wiring part 31 has, for example, a wiring 31a, a wiring 31b, and a terminal 31c. The wiring 31a, the wiring 31b, and the terminal 31c can be integrally formed.
The wiring 31a is provided near one edge of the substrate 10 in the Y direction. The wiring 31 a extends in the X direction along one edge of the substrate 10 .
The wiring 31b is provided near the other peripheral edge of the substrate 10 in the Y direction. The wiring 31b extends in the X direction along the other peripheral edge of the substrate 10 .
The terminals 31c are provided near both ends of the substrate 10 in the X direction. One end of the wiring 31a and the wiring 31b is electrically connected to one terminal 31c. The other ends of the wirings 31a and 31b are electrically connected to the other terminal 31c. Although the case where two terminals 31c are provided is illustrated, one terminal 31c may be provided near one end of the substrate 10 in the X direction. However, if the length of the substrate 10 in the X direction (the length of the wiring 31a and the wiring 31b) is long, it is preferable to provide the terminals 31c near both ends of the substrate 10 in the X direction.

The wiring portion 32 is provided in the central region of the substrate 10 in the Y direction. The wiring part 32 has, for example, a wiring 32a and a terminal 32b. The wiring 32a and the terminal 32b can be integrally formed.
The wiring 32a is provided between the wiring 31a and the wiring 31b of the wiring portion 31 in the Y direction. That is, the wiring 32a is separated from the wirings 31a and 31b in the Y direction orthogonal to the X direction. The wiring 32a extends in the X direction along the periphery of the substrate 10. As shown in FIG.

The terminals 32b are provided near both ends of the substrate 10 in the X direction. In the X direction, the terminal 32b is provided closer to the center of the substrate 10 than the terminal 31c. One end of the wiring 32a is electrically connected to one terminal 32b. The other end of the wiring 32a is electrically connected to the other terminal 32b. Although the case where two terminals 32b are provided is illustrated, one terminal 32b may be provided near one end of the substrate 10 in the X direction. However, when the length of the substrate 10 in the X direction (the length of the wiring 32a) is long, it is preferable to provide the terminals 32b near both ends of the substrate 10 in the X direction.

One end of each of the multiple heating elements 21 is electrically connected to the wiring 31 a of the wiring portion 31 . The other ends of the multiple heating elements 21 are electrically connected to the wiring 32 a of the wiring section 32 . That is, the plurality of heating elements 21 are connected in parallel.
One end of each of the multiple heating elements 22 is electrically connected to the wiring 31 b of the wiring section 31 . The other ends of the multiple heating elements 22 are electrically connected to the wiring 32 a of the wiring portion 32 . That is, the plurality of heating elements 22 are connected in parallel.

The wiring portion 31 and the wiring portion 32 can be formed using a material containing silver, copper, or the like, for example. In this case, the wiring portion 31 and the wiring portion 32 are formed by, for example, applying a paste material to the surface of the substrate 10 on which the heat generating portion 20 is provided using a screen printing method or the like, and then applying a paste using a baking method or the like. It can be formed by curing a shaped material.

The protective film 40 covers the heating element 21 , the heating element 22 , the wiring section 31 and the wiring section 32 . In this case, the terminal 31c of the wiring portion 31 and the terminal 32b of the wiring portion 32 can be exposed from the protective film 40 for electrical connection with a power supply or the like.

The protective film 40 has, for example, a function of insulating the heating element 21, the heating element 22, the wiring part 31, and the wiring part 32, a function of transmitting heat generated in the heating element 21 and the heating element 22 to the outside, and a function of protecting against external force and corrosion. It has a function of protecting the heating element 21, the heating element 22, the wiring part 31, and the wiring part 32 from toxic gases.

The protective film 40 is preferably made of a material that has heat resistance, insulation, and high chemical stability. The protective film 40 can be formed using ceramics, glass, or the like, for example. In this case, the formation of the protective film 40 can be facilitated by using glass to which a filler containing a material with high thermal conductivity such as aluminum oxide is added. The thermal conductivity of glass to which a filler is added can be, for example, 2 [W/(m·K)] or more. For the protective film 40, for example, a paste-like material is applied onto the substrate 10, the heat-generating part 20, the wiring part 31, and the wiring part 32 using a screen printing method or the like, and then a paste-like material is applied using a baking method or the like. It can be formed by curing the material.

Also, a temperature sensor and wiring electrically connected to the temperature sensor can be provided on the surface of the substrate 10 opposite to the side on which the heat generating portion 20 is provided. The temperature sensor can be, for example, a film-like thermistor. A film-like thermistor can be formed by, for example, applying a paste-like material to the surface of the substrate 10 using a screen printing method or the like, and curing the paste-like material using a baking method or the like. For example, a film-like thermistor can be formed using a material containing barium titanate, a material containing oxide, or the like. The oxides can be, for example, oxides of nickel, manganese, cobalt, iron, copper, and the like.

Wiring electrically connected to the temperature sensor can be formed, for example, using a screen printing method, a baking method, or the like, similarly to the wiring portions 31 and 32 described above. A protective film may also be provided to cover the temperature sensor and wiring. The protective film can be, for example, similar to the protective film 40 described above.

Next, the planar shapes of the heating elements 21 and 22 will be described.
First, the planar shape of the heating elements 221 and 222 according to the comparative example will be described.
FIG. 3A is a schematic plan view for illustrating the planar shape of heat generating elements 221 and 222 according to the comparative example.
FIG. 3B is a schematic enlarged plan view of the heating element 221. FIG.
FIG. 3C is a schematic enlarged plan view of the heating element 222. FIG.

As shown in FIGS. 3A to 3C, the planar shape of the heating elements 221 and 222 is a parallelogram.
As shown in FIG. 3A, the heating element 221 is electrically connected to the wiring 31a and the wiring 32a. The heating element 221 is inclined with respect to the direction (X direction) in which the wirings 31a and 32a extend.
As shown in FIG. 3B, one corner of the heating element 221 on the side connected to the wiring 31a is an obtuse angle θ1, and the other angle is an acute angle θ2. One corner of the heating element 221 connected to the wiring 32a is an obtuse angle .theta.3, and the other angle is an acute angle .theta.4.

As shown in FIG. 3A, the heating element 222 is electrically connected to the wiring 31b and the wiring 32a. The heating element 222 is inclined with respect to the direction (X direction) in which the wiring 31b and the wiring 32a extend.
As shown in FIG. 3C, one corner of the heating element 222 connected to the wiring 31b is an obtuse angle .theta.5, and the other angle is an acute angle .theta.6. One corner of the heating element 222 connected to the wiring 32a is an obtuse angle θ7, and the other angle is an acute angle θ8.

Here, if the corners of the heating element are acute, electric field concentration is likely to occur in the vicinity of the acute corners. In this case, the smaller the acute angle, the greater the intensity of the electric field. When the strength of the electric field increases, dielectric breakdown may occur in the vicinity of the connection between the heating element and the wiring, causing a large current to flow. For example, when a rush current or surge current flows through the heater, dielectric breakdown is more likely to occur. If dielectric breakdown occurs and a large current flows, at least one of the heating element and wiring may be damaged.

FIG. 4(a) is a schematic plan view for illustrating the planar shape of the heating elements 21 and 22 according to this embodiment.
FIG. 4B is a schematic enlarged plan view of the heating element 21. FIG.
FIG. 4C is a schematic enlarged plan view of the heating element 22. FIG.

As shown in FIG. 4A, the heating element 21 is electrically connected to wiring 31a and wiring 32a. The heating element 21 is inclined with respect to the direction (X direction) in which the wirings 31a and 32a extend.
As shown in FIG. 4B, the angles of the heating element 21 on the side connected to the wiring 31a are all obtuse angles θa to θc. The angles of the heating element 21 on the side connected to the wiring 32a are all obtuse angles θd to θf.

As shown in FIG. 4A, the heating element 22 is electrically connected to the wiring 31b and the wiring 32a. The heating element 22 is inclined with respect to the direction (X direction) in which the wiring 31b and the wiring 32a extend.
As shown in FIG. 4(c), the angles of the heating element 22 on the side connected to the wiring 31b are all obtuse angles θg to θi. The angles of the heating element 22 on the side connected to the wiring 32a are all obtuse angles θj to θl.

As shown in FIG. 4A, if a plurality of inclined portions 21 and 22 inclined with respect to the X direction are arranged side by side in the X direction, the occurrence of temperature distribution in the heater 1 (substrate 10) can be suppressed. can do.

In the heat generating elements 21 and 22 according to the present embodiment, since the angles of the heat generating elements 21 and 22 are all obtuse angles, a It is possible to suppress the occurrence of electric field concentration in the vicinity of the connection portions with the wirings 31b and 32a. Also, the strength of the generated electric field can be reduced. Therefore, for example, even if a rush current or a surge current flows through the heater 1, it is possible to suppress the occurrence of dielectric breakdown in the vicinity of the corners of the heating elements 21 and 22. FIG. As a result, it is possible to suppress damage to the heating elements 21 and 22 and the wirings 31a, 31b, and 32a.

The planar shapes of the heating elements 21 and 22 are not limited to those illustrated in FIGS. 4(a) to 4(c), and the angles on the side connected to the wiring are all obtuse or right angles. Any shape may be used. For example, the planar shape of the heating elements 21 and 22 may be a rectangle or a square whose corners on the side connected to the wiring are all right angles. However, since the strength of the generated electric field can be reduced as the angle of the corners increases, it is preferable that the planar shapes of the heating elements 21 and 22 have obtuse angles on the sides connected to the wiring. .

FIG. 5(a) is a schematic plan view for illustrating the planar shape of heating elements 21a and 22a according to another embodiment.
FIG. 5B is a schematic enlarged plan view of the heating element 21a.
FIG. 5(c) is a schematic enlarged plan view of the heating element 22a.

As shown in FIG. 5A, the heating element 21a is electrically connected to the wiring 31a and the wiring 32a. The heating element 21a is inclined with respect to the direction (X direction) in which the wiring 31a and the wiring 32a extend.
As shown in FIG. 5(b), the contour of the end of the heating element 21a on the side connected to the wiring 31a is composed of curved lines. The contour of the end of the heating element 21a on the side connected to the wiring 32a is composed of a curved line. In this case, it is preferable that the contour of the end portion of the heating element 21a is formed by a convex curved line protruding toward the outside of the heating element 21a.

As shown in FIG. 5A, the heating element 22a is electrically connected to the wiring 31b and the wiring 32a. The heating element 22a is inclined with respect to the direction (X direction) in which the wirings 31b and 32a extend.
As shown in FIG. 5(c), the contour of the end portion of the heating element 22a on the side connected to the wiring 31b is composed of curved lines. The contour of the end of the heating element 22a on the side connected to the wiring 32a is composed of a curved line. In this case, it is preferable that the contour of the end portion of the heating element 22a is formed by a convex curved line protruding toward the outside of the heating element 22a.

As shown in FIG. 5(a), if a plurality of inclined portions 21a and 22a inclined with respect to the X direction are arranged side by side in the X direction, the occurrence of temperature distribution in the heater 1 (substrate 10) can be suppressed. can do.

In the heat generating elements 21a and 22a according to the present embodiment, the contours of the end portions of the heat generating elements 21a and 22a are formed by curved lines. It is possible to suppress the occurrence of electric field concentration in the vicinity of the connecting portions between the body 22a and the wirings 31b and 32a. Also, the strength of the generated electric field can be reduced. Therefore, for example, even when a rush current or a surge current flows through the heater 1, it is possible to suppress the occurrence of dielectric breakdown in the vicinity of the ends of the heating elements 21a and 22a. As a result, it is possible to suppress damage to the heating elements 21a, 22a and the wirings 31a, 31b, 32a.

The planar shapes of the heating elements 21a and 22a are not limited to those illustrated in FIGS. 5(a) to 5(c). It is good if there is. For example, the planar shape of the heating elements 21a and 22a may be a curved shape such as an ellipse.

Also, the corners of one end of the heating element may be obtuse or right angles, and the contour of the other end of the heating element may be a curved line.

Next, the ratio of ruthenium oxide contained in the heating element will be further explained.
As described above, the heating element contains at least ruthenium oxide. According to knowledge obtained by the present inventors, dielectric strength can be improved by adjusting the resistance value of the heating element by changing the ratio of ruthenium oxide contained in the heating element. For example, if the ratio of ruthenium oxide is increased, the resistance value of the heating element can be reduced, so that the dielectric strength against surge voltage can be improved. However, if the proportion of ruthenium oxide is too large, the resistance of the heating element becomes too small, and the difference between the resistance of the heating element and the wiring becomes small. If the difference between the resistance value of the heating element and the resistance value of the wiring becomes small, the amount of heat generated in the wiring increases, which may cause problems such as temperature distribution in the heater (substrate).

FIG. 6 is a table for illustrating the relationship between the ratio of ruthenium oxide contained in the heating element, the dielectric strength, and the amount of heat generated by wiring.
Note that the heating element contained ruthenium oxide and copper oxide.
In dielectric strength evaluation, the applied power varies depending on the resistance value of the heating element, and the power is dispersed depending on the number of heating elements connected in parallel. It was evaluated in terms of applied power per body. The applied power per heating element can be described as follows. From Ohm's law, voltage = current x resistance value, and power = voltage x current, it can be described as power = voltage x voltage / resistance value. Electric power=voltage×voltage/resistance/number of heating elements. The evaluation was performed with an applied power of 800 W per heating element.
The length of the heating element in the direction in which the heating element extends was set to 5.0 mm. The length (width) of the heating element in the direction orthogonal to the extending direction of the heating element was set to 0.5 mm. The thickness of the heating element was 17 μm.
The planar shape of the heating element is illustrated in FIG.

As can be seen from FIG. 6, if the ratio of ruthenium oxide contained in the heating element is 8 wt % or more and 20 wt % or less, dielectric strength can be improved and heat generation in wiring can be suppressed. Furthermore, if the ratio of ruthenium oxide contained in the heating element is set to 13 wt % or more and 20 wt % or less, the dielectric strength can be further improved.

Next, the image forming apparatus 100 according to this embodiment will be described.
(Image forming device)
In the following, as an example, the case where the image forming apparatus 100 is a copier will be described. However, the image forming apparatus 100 is not limited to a copier, and may be any apparatus provided with a heater for fixing toner. For example, the image forming apparatus 100 can be a printer or the like.

FIG. 7 is a schematic diagram for illustrating the image forming apparatus 100 according to this embodiment.
FIG. 8 is a schematic diagram for illustrating the fixing section 200. As shown in FIG.
As shown in FIG. 7, the image forming apparatus 100 includes a frame 110, an illumination unit 120, an imaging element 130, a photosensitive drum 140, a charging unit 150, a discharging unit 151, a developing unit 160, a cleaner 170, a storage unit 180, a conveying unit A section 190, a fusing section 200, and a controller 210 may be provided.

The frame 110 has a box-like shape and contains an illumination section 120, an image forming element 130, a photosensitive drum 140, a charging section 150, a developing section 160, a cleaner 170, a part of a storage section 180, a conveying section 190, and a fixing section. 200 and controller 210 can be accommodated.
A window 111 made of a translucent material such as glass can be provided on the top surface of the frame 110 . A document 500 to be copied can be placed on the window 111 . Also, a moving unit for moving the position of the document 500 can be provided.

The lighting unit 120 can be provided near the window 111 . The illumination section 120 may comprise a light source 121 such as a lamp and a reflector 122 .
The imaging element 130 can be provided near the window 111 .
The photosensitive drum 140 can be provided below the illumination section 120 and the imaging element 130 . The photosensitive drum 140 can be rotatably provided. The surface of the photosensitive drum 140 can be provided with, for example, a zinc oxide photosensitive layer or an organic semiconductor photosensitive layer.
The charging unit 150 , the discharging unit 151 , the developing unit 160 and the cleaner 170 can be provided around the photosensitive drum 140 .

Storage unit 180 has cassette 181 and tray 182 . Cassette 181 can be removably attached to one side of frame 110 . The tray 182 can be provided on the side of the frame 110 opposite to the side on which the cassette 181 is attached. Cassette 181 stores paper 510 (for example, blank paper) before copying is performed. The tray 182 accommodates the paper 511 on which the copy image 511a is fixed.

The conveying unit 190 can be provided below the photosensitive drum 140 . The transport section 190 transports the paper 510 between the cassette 181 and the tray 182 . The transport unit 190 includes a guide 191 that supports the transported paper 510 and transport rollers 192 to 194 that transport the paper 510 . Further, the transport section 190 can be provided with a motor for rotating the transport rollers 192 to 194 .

The fixing section 200 can be provided downstream of the photosensitive drum 140 (on the tray 182 side).
As shown in FIG. 8, the fixing section 200 has a heater 1, a stay 201, a film belt 202, and a pressure roller 203, for example.
A heater 1 can be attached to the stay 201 on the paper 510 transport line side. The heater 1 can be embedded in the stay 201 . The side of the heater 1 on which the protective film 40 is provided can be exposed from the stay 201 .

A film belt 202 covers a stay 201 on which the heater 1 is provided. The film belt 202 can contain, for example, heat-resistant resin such as polyimide.

The pressure roller 203 can be provided so as to face the stay 201 . The pressure roller 203 has a metal core 203a, a drive shaft 203b, and an elastic portion 203c. The drive shaft 203b protrudes from the end of the metal core 203a and is connected to a drive device such as a motor. The elastic portion 203c can be provided on the outer surface of the metal core 203a. The elastic portion 203c is made of a heat-resistant elastic material. The elastic portion 203c contains, for example, silicone resin.

Controller 210 is provided inside frame 110 . The controller 210 has, for example, an arithmetic unit such as a CPU (Central Processing Unit) and a storage unit in which a control program is stored. The calculation unit controls the operation of each element provided in the image forming apparatus 100 based on the control program stored in the storage unit. The controller 210 can also include an operation unit for inputting copying conditions by the user, a display unit for displaying operation status, error display, and the like.
A known technique can be applied to control the operation of each element provided in the image forming apparatus 100, so detailed description thereof will be omitted.

Although some embodiments of the present invention have been illustrated above, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, changes, etc. can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof. Moreover, each of the above-described embodiments can be implemented in combination with each other.

Reference Signs List 1 heater 10 substrate 20 heating part 21 heating element 21a heating element 22 heating element 22a heating element 31 wiring part 31a wiring 31b wiring 32 wiring part 32a wiring 100 image forming apparatus 200 fixing Department

Claims (3)

a substrate having a plate shape and extending in a first direction;
a first wiring provided on one surface of the substrate and extending in the first direction;
a second wiring provided on one surface of the substrate, separated from the first wiring in a second direction orthogonal to the first direction, and extending in the first direction;
a plurality of heating elements provided between the first wiring and the second wiring and arranged in the first direction;
and
Seen from a direction perpendicular to one surface of the substrate,
The angles of the plurality of heating elements on the side connected to the first wiring are all obtuse angles or right angles, or the contours of the ends of the sides connected to the first wiring are composed of curved lines,
A heater in which the angles of the plurality of heating elements on the side connected to the second wiring are all obtuse angles or right angles, or the outline of the end portion on the side connected to the second wiring is a curved line. . 2. The heater according to claim 1, wherein the plurality of heat generating elements contain ruthenium oxide, and the proportion of said ruthenium oxide contained in said plurality of heat generating elements is 8 wt % or more and 20 wt % or less. An image forming apparatus comprising the heater according to claim 1 or 2.

Images