JP2023033822A - Fixing device and image forming apparatus - Google Patents

Abstract

To provide a fixing device that can prevent the occurrence of positional deviation between a heater and a connector even when a substrate composed of metal material is used for the heater, and an image forming apparatus.SOLUTION: A fixing device (45) comprises: a heater (60) that has a substrate composed of metal material and a resistance heating element; a holder (70) that holds the heater (60); a wire spring (110) that retains the heater (60) on the holder (70) so that the heater (60) is held on the holder (70); and a connector that supplies power to the heater (60). The wire spring (110) has an engagement part (113) that is engaged with the substrate and the holder (70) at an end in a width direction orthogonal to a longitudinal direction of the heater (60).SELECTED DRAWING: Figure 7

Description

The present disclosure relates to fixing devices and image forming apparatuses.

2. Description of the Related Art Image forming apparatuses such as electrophotographic printers are known to have a fixing device that heats a sheet on which an image is to be formed to fix a developer image. Such a fixing device includes a substrate, a heater having a resistive heating element arranged on the substrate, and a holder that holds the heater (see, for example, Japanese Unexamined Patent Application Publication No. 2002-100003).

Japanese Patent Application Laid-Open No. 2020-52348

In the fixing device as described above, a connector for supplying power to the resistance heating element is provided at the longitudinal end of the heater.

However, in the conventional fixing device as described above, there is a problem that the relative positions of the heater and the connector are displaced due to thermal expansion or thermal contraction in the longitudinal direction of the heater caused by heat generation or stoppage of the heater. there was a point In particular, when a substrate made of a metal material is used as the substrate of the heater, the above-mentioned thermal expansion or thermal contraction is greater than that of a substrate made of a ceramic material or the like, causing a relative positional deviation between the heater and the connector. However, there is a problem that it is likely to occur.

SUMMARY OF THE INVENTION An object of the present disclosure is to provide a fixing device and an image forming apparatus that can suppress the occurrence of misalignment between a heater and a connector even when a substrate made of a metal material is used for the heater.

In order to solve the above problems, a fixing device according to a first aspect of the present disclosure includes: a heater having a substrate made of a metal material; a resistance heating element arranged on the substrate; a holder for holding the heater; A fastening member for fastening the heater to the holder and a connector for supplying power to the heater are provided so that the heater is held by the holder, and the fastening member is provided on one end side and the other end side in the longitudinal direction of the heater. The connector is arranged on at least one of the one end side and the other end side of the heater, and the fastening member is arranged at an end in the width direction perpendicular to the longitudinal direction of the heater , an engaging portion that engages with the substrate and the holder.

According to the above configuration, the fastening member has the engaging portion that engages the substrate and the holder at the end portion in the width direction orthogonal to the longitudinal direction of the heater. However, the heater can be held by the holder without positional deviation. As a result, even when a substrate made of a metal material is used as a heater, it is possible to configure a fixing device capable of suppressing the occurrence of positional deviation between the heater and the connector.

A second aspect of the present disclosure is the fixing device of the first aspect, wherein the fastening member includes a first facing portion that faces the first surface of the heater and supports the first surface, and the first facing portion that supports the first surface. a first engaging portion that extends from one end of the portion and engages with the holder at one end in the width direction; a second engaging portion that engages the holder on the side thereof, wherein the engaging portion is at least one of the first engaging portion and the second engaging portion, and engages the substrate; may

According to the above configuration, the fastening member can contact the side surface of the substrate on both one side and the other side in the width direction of the heater, and the substrate can be more stably grounded.

A third aspect of the present disclosure is the fixing device of the second aspect, wherein the fastening member may be a wire spring.

According to the above configuration, at least one of the first engaging portion and the second engaging portion formed on the wire spring causes misalignment between the heater and the connector even when a substrate made of a metal material is used as the heater. is suppressed, the length of the heater and the holder in the longitudinal direction can be shortened.

A fourth aspect of the present disclosure is the fixing device according to any one of the first to third aspects, wherein the holder may have a mounting hole into which the engaging portion is inserted.

According to the above configuration, the fastening member can be engaged with the holder by inserting the engaging portion into the mounting hole.

A fifth aspect of the present disclosure is the fixing device according to any one of the first aspect to the fourth aspect, wherein the holder may have a holder side groove with which the engaging portion is engaged.

According to the above configuration, the fastening member can be positioned with respect to the holder by engaging the engaging portion with the holder side groove.

A sixth aspect of the present disclosure is the fixing device according to the fifth aspect, wherein the substrate may have a substrate side groove that faces the holder side groove and is engaged with the engaging portion.

According to the above configuration, the fastening member can be positioned with respect to the heater and the holder by engaging the engaging portion with the board side groove.

A seventh aspect of the present disclosure is the fixing device according to any one of the first aspect to the sixth aspect, wherein the fastening member has conductivity and abuts on the side surface of the substrate to electrically fix the substrate. may be grounded to

According to the above configuration, the electrically conductive fastening member abuts against the side surface of the substrate to electrically ground the substrate. Can be stably and properly grounded.

An eighth aspect of the present disclosure is the fixing device of the seventh aspect, further comprising an endless belt whose inner peripheral surface is in contact with the heater, wherein the shortest distance between the fastening member and the belt is the It may be smaller than the shortest distance between the connector and the belt.

According to the above configuration, when the belt is charged, the electrical discharge to the connector can be suppressed, and the belt can be neutralized by the fastening member.

A ninth aspect of the present disclosure is the fixing device according to the eighth aspect, wherein the fastening member may be arranged between the connector and the belt.

According to the above configuration, when the belt is electrified, it is possible to reliably neutralize the belt by the fastening member.

An image forming apparatus according to a tenth aspect of the present disclosure includes the fixing device according to any one of the first to ninth aspects.

According to the above configuration, it is possible to configure an image forming apparatus that can suppress the occurrence of positional deviation between the heater and the connector even when a substrate made of a metal material is used for the heater.

According to one aspect of the present disclosure, it is possible to provide a fixing device and an image forming apparatus that can suppress the occurrence of misalignment between a heater and a connector even when a substrate made of a metal material is used for the heater.

1 is a diagram illustrating a schematic configuration of an image forming apparatus according to Embodiment 1 of the present disclosure; FIG. FIG. 2 is a cross-sectional view showing the main configuration of the fixing device shown in FIG. 1; 3 is a plan view showing a heating unit included in the fixing device; FIG. (A) is an exploded perspective view illustrating a specific configuration of a heater included in the heating unit, and (B) is a cross-sectional view illustrating a cross section of the heater. FIG. 3 is a diagram for explaining a detailed configuration example of a main part of the fixing device; FIG. 4 is a perspective view showing a specific configuration of the connector shown in FIG. 3; FIG. 2 is a cross-sectional view showing a configuration example of a main part of the fixing device; FIG. 8 is a perspective view showing a specific configuration of the wire spring shown in FIG. 7; FIG. 5 is a cross-sectional view showing a configuration example of a main part of a fixing device included in an image forming apparatus according to Embodiment 2 of the present disclosure;

[Embodiment 1]
Embodiment 1 of the present disclosure will be described below with reference to FIGS. 1 to 8. FIG. In this embodiment, as an example of the image forming apparatus 1, a laser printer that forms an image on a sheet S1 using toner will be described.

[Configuration of Image Forming Apparatus 1]
FIG. 1 is a diagram illustrating a schematic configuration of an image forming apparatus 1 according to Embodiment 1 of the present disclosure. In the following description, the image forming apparatus 1 is exemplified by a monochrome printer that performs image forming processing of a monochrome image, but the present embodiment is not limited to this. It may be a color printer that performs

As shown in FIG. 1, the image forming apparatus 1 includes a housing 2, a paper feeding unit 3, an image forming unit 4, a discharge roller 5, a discharge tray 6, and a main motor M. As shown in FIG. 1 , the housing 2 constitutes an outer container of the image forming apparatus 1 and accommodates the main components of the image forming apparatus 1 .

As shown in FIG. 1, the sheet feeding unit 3 supplies a sheet S1. The paper feeding unit 3 includes a paper feeding tray 31 , a feeding roller 32 , a pressing plate 33 , a conveying roller 34 and a registration roller 35 . The paper feed tray 31 is a box-shaped member with an open top, and accommodates a predetermined amount of sheets S1. Also, the sheet S1 is a recording medium on which an image forming process is performed, and is made of paper, plastic, or the like.

The feeding roller 32 feeds out the sheet S1 accommodated in the paper feed tray 31 . That is, when the sheet S1 is sent out, the sheet S1 on the sheet feeding tray 31 is pushed toward the feeding roller 32 by the pressing plate 33 and is fed to the conveying roller 34 as the feeding roller 32 rotates. The conveying rollers 34 convey the sheet S<b>1 toward the registration rollers 35 . The registration rollers 35 convey the sheet S1 toward the image forming section 4 after aligning the positions of the leading edges of the sheet S1.

The image forming section 4 forms an image by performing an image forming process on the sheet S1 sent out by the paper feeding section 3 . As shown in FIG. 1 , the image forming section 4 includes an exposure device 41 , a transfer device 42 , a charging device 43 , a developing section 44 , a fixing device 45 of the present disclosure, and a photosensitive drum 46 . The exposure device 41 includes a laser light source (not shown), a polygon mirror 41G, a scanning lens 41L, a polygon motor 41M, and a reflecting mirror 41R.

The polygon mirror 41G is a rotary polygon mirror having six reflecting surfaces on the sides of a regular hexagonal prism. The polygon mirror 41G is for deflecting the light beam L1 emitted by the laser light source in the direction toward the photosensitive drum 46. As shown in FIG. The polygon motor 41M rotates the polygon mirror 41G by being driven by a motor driver (not shown).

The exposure unit 41 deflects the light beam L1 by the polygon mirror 41G, and emits the light beam L1 from the polygon mirror 41G to the surface of the photosensitive drum 46 via the scanning lens 41L and the reflecting mirror 41R. The exposure unit 41 exposes the photosensitive drum 46 by scanning the surface of the photosensitive drum 46 with the light beam L1. As a result, an electrostatic latent image forming a toner image, which will be described later, is formed on the photosensitive drum 46 . Polygon motor 41M is, for example, a brushless DC motor.

The transfer device 42 includes a transfer roller that sandwiches the sheet S1 between itself and a photosensitive drum 46, and transfers the toner image from the photosensitive drum 46 onto the sheet S1. The charger 43 includes, for example, a scorotron-type charger having a charging wire (not shown) and a grid portion. In the charger 43, a high voltage generation circuit (not shown) applies a charging voltage to the charging wire, and a grid voltage is applied to the grid portion, thereby generating corona discharge and making the surface of the photosensitive drum 46 uniform. charged to The developing unit 44 includes a developing roller 44R and a toner cartridge 44A containing a developer such as toner.

In addition to the above description, for example, instead of the transfer roller, the transfer device 42 may include a transfer belt. Further, for example, instead of the scorotron type charger, the charger 43 may include a charging roller.

In the image forming unit 4 , after the surface of the photosensitive drum 46 is uniformly charged by the charger 43 , an electrostatic latent image based on the print data is formed on the surface of the photosensitive drum 46 by the light beam L 1 from the exposure device 41 . It is formed. Further, the developing roller 44R supplies toner from inside the toner cartridge 44A to the surface of the photosensitive drum 46 on which the electrostatic latent image is formed. As a result, the electrostatic latent image is visualized and a toner image is formed on the surface of the photosensitive drum 46 . After that, the sheet S1 fed from the paper feeding unit 3 is conveyed to a transfer position between the photosensitive drum 46 and the transfer device 42, and the toner image formed on the surface of the photosensitive drum 46 is transferred to the sheet S1. transcribed above.

The sheet S<b>1 to which the toner image has been transferred is conveyed to the fixing device 45 by the photosensitive drum 46 and transfer device 42 . The fixing device 45 fixes the toner image formed on the sheet S1. Specifically, the fixing device 45 uses the heat generated by the heater 60 to thermally fix the toner image on the sheet S1 conveyed from the photosensitive drum 46 and transfer device 42 . The sheet S<b>1 on which the toner image is thermally fixed is discharged onto the discharge tray 6 by the discharge rollers 5 . A specific configuration of the fixing device 45 in Embodiment 1 will be described in detail later.

The main motor M is, for example, a brushless DC motor. The main motor M is connected to a transmission mechanism such as a gear for transmitting its rotational force, and the main motor M functions as a power source for each part housed inside the housing 2 .

[Structure of Fixing Device 45]
2 and 3, the fixing device 45 of this embodiment will be specifically described. FIG. 2 is a cross-sectional view showing the essential configuration of the fixing device 45 shown in FIG. FIG. 3 is a plan view showing the heating unit 51 included in the fixing device 45. As shown in FIG.

As shown in FIG. 2, the fixing device 45 of this embodiment includes a heating unit 51 that contacts the sheet S1 on which a toner image is formed and heats the sheet S1, and a pressure roller 52 that presses the sheet S1. One of the heating unit 51 and the pressure roller 52 is pressed toward the other by a pressing portion (not shown). In the fixing device 45, the pressing section is controlled in accordance with instructions from a control section (not shown), so that a predetermined pressure is applied between the heating unit 51 and the pressure roller 52, and toner is applied to the sheet S1. Image fixing processing is performed.

The heating unit 51 has a heater 60 , a holder 70 , a stay 80 and a belt 90 . The heater 60 is a heating member having a rectangular shape in plan view. The heater 60 has a first surface 60A arranged on the pressure roller 52 side and a second surface 60B facing the first surface 60A. , supported by the holder 70 .

The holder 70 is made of, for example, a synthetic resin material, and includes a guide surface 70A that guides the belt 90 and a support portion 70B that supports the heater 60. As shown in FIG. Guide surface 70A guides belt 90 by contacting inner peripheral surface 90A of belt 90 . The support portion 70B includes a support surface 70B1 that contacts and supports the second surface 60B of the heater 60 . The stay 80 is a reinforcing member that supports the holder 70, and is formed by bending a metal material such as a plate material having greater rigidity than the holder 70, for example, a steel plate, into a substantially U-shaped cross section.

The belt 90 is an endless belt having heat resistance and flexibility. (not shown). The belt 90 rotates around the heater 60 , the holder 70 and the stay 80 while accommodating the heater 60 , the holder 70 and the stay 80 inside. Further, the inner peripheral surface 90A of the belt 90 is in contact with the first surface 60A of the heater 60, so that the heat from the heater 60 is transmitted to the sheet S1 via the belt 90. As shown in FIG.

The pressure roller 52 includes a rotating shaft 52A made of a metal material and an elastic layer 52B made of a synthetic rubber material or the like and covering the surface of the rotating shaft 52A. The pressure roller 52 and the heater 60 sandwich the belt 90 to form a nip portion NP for heating and pressing the sheet S1.

The pressure roller 52 is driven to rotate in the rotation direction R2 by transmission of the driving force from the main motor M according to the instruction from the control unit. That is, the pressure roller 52 rotates while nipping the sheet S1 conveyed in the conveying direction H between itself and the belt 90, whereby the pressure roller 52, the belt 90, and the sheet S1 are rotated. It is configured to be driven to rotate in the rotation direction R1 by each frictional force. As a result, in the fixing device 45, the sheet S1 onto which the toner image has been transferred is conveyed between the heating unit 51 and the pressure roller 52, thereby thermally fixing the toner image onto the sheet S1.

As shown in FIG. 3, in the heating unit 51, the connector 100 and the wire spring 110 are provided on one end side of the heater 60 in the longitudinal direction LH. The connector 100 is connected to a power supply (not shown) and supplies power from the power supply to the heater 60 . The connector 100 supplies electric power to the heater 60 while sandwiching the heater 60 and the holder 70 (details will be described later).

The wire spring 110 constitutes a fastening member that fastens the heater 60 to the holder 70 so that the heater 60 is held by the holder 70 . As will be described later, the wire spring 110 has a second spring as an engaging portion that engages the substrate S and the holder 70 described later in the heater 60 at the end portion in the width direction SH perpendicular to the longitudinal direction LH of the heater 60 . An engaging portion 113 is provided.

[Structure of Heater 60]
Next, the heater 60 will be specifically described with reference to FIG. 4 as well. FIG. 4A is an exploded perspective view for explaining a specific configuration of the heater 60 included in the heating unit 51, and FIG. 4B is a cross-sectional view showing a cross section of the heater 60.

As shown in FIGS. 4A and 4B, the heater 60 includes a first insulating layer Z1 having the second surface 60B, a substrate S laminated on the first insulating layer Z1, a substrate S It comprises a second insulating layer Z2 laminated thereon, a resistance heating element P arranged on the second insulation layer Z2, and a third insulation layer Z3 arranged so as to cover the resistance heating element P. The first insulating layer Z1, the second insulating layer Z2, and the third insulating layer Z3 are made of, for example, an insulator such as a glass material. The third insulating layer Z3 has the first surface 60A and is in contact with the inner peripheral surface 90A of the belt 90, and serves as a protective layer that protects the resistance heating element P from contact with the inner peripheral surface 90A. also works.

The resistance heating element P includes a power supply terminal T having two terminals T1 and T2, a power supply pattern PE having power supply patterns PE1 and PE2 electrically connected to the terminals T1 and T2, respectively, and a power supply pattern PE electrically connected to the power supply pattern PE. and a connected heating pattern PH.

At least the heating pattern PH of the resistance heating element P is made of, for example, a conductive material with excellent heat generation such as nickel-chromium alloy or iron-chromium alloy. heat is generated according to In other words, the current supplied to the heating pattern PH is controlled, and the heat generated by the heating pattern PH is increased or decreased to control the heating of the belt 90 from the heater 60 .

The fixing device 45 of the present embodiment is provided with a temperature sensor (not shown) for detecting the temperature of the heater 60, and the controller controls the heater 60 using the detection result of the temperature sensor. is configured as

The substrate S is made of, for example, a metal material such as stainless steel. The substrate S is provided with a substrate side groove SA that engages with the second engaging portion 113 of the wire spring 110 . Further, in the heater 60, grooves Z1A, Z2A, and Z3A facing the substrate side groove SA are provided in the first insulating layer Z1, the second insulating layer Z2, and the third insulating layer Z3, respectively. The substrate side groove SA also faces a holder side groove, which will be described later.

That is, in the heater 60, the substrate side grooves SA are formed at substantially the same positions as the grooves Z1A, Z2A, and Z3A and the holder side grooves in the longitudinal direction LH, and the wire spring 110 is attached to the heating unit 51. At times, the substrate side groove SA, the grooves Z1A, Z2A, and Z3A are engaged with the second engaging portion 113 together with the holder side grooves.

In the above description, the heater 60 having the first insulating layer Z1, the substrate S, the second insulating layer Z2, the resistance heating element P, and the third insulating layer Z3 was described. As long as it has a substrate S made of a metal material and a resistance heating element P arranged on the substrate S, there is no limitation.

[Main Configuration of Fixing Device 45]
Next, with reference to FIGS. 5 to 8 as well, the main configuration of the fixing device 45 of this embodiment will be specifically described. FIG. 5 is a diagram for explaining a detailed configuration example of a main part of the fixing device 45. As shown in FIG. FIG. 6 is a perspective view showing a specific configuration of connector 100 shown in FIG. FIG. 7 is a cross-sectional view showing an example of the main configuration of the fixing device 45. As shown in FIG. FIG. 8 is a perspective view showing a specific configuration of wire spring 110 shown in FIG. 5, illustration of the connector 100 and the third insulating layer Z3 of the heater 60 is omitted.

As shown in FIG. 5, in the fixing device 45 of this embodiment, the wire spring 110 is arranged on one end side of the heater 60 in the longitudinal direction LH. Further, the wire spring 110 is formed continuously at a first facing portion 111 facing the first surface 60A of the heater 60 and one end and the other end of the first facing portion 111, as will be described in detail later. A first engaging portion 112 and a second engaging portion 113 are provided.

The wire spring 110 is installed within an installation area K indicated by a double arrow in FIG. This installation area K is an area between the installation location of the connector 100 electrically connected to the terminals T1 and T2 and the installation location of the belt 90 indicated by the one-dot chain line in FIG. In the wire spring 110, the second engaging portion 113, which is installed within the setting region K, engages with the substrate S and the holder 70, so that the heater 60 can be moved without causing positional deviation. It is held by a holder 70 .

That is, in the fixing device 45 of this embodiment, the wire spring 110 is arranged between the connector 100 and the belt 90 as shown in FIG. Furthermore, the fixing device 45 of this embodiment is configured such that the shortest distance between the wire spring 110 and the belt 90 is smaller than the shortest distance between the connector 100 and the belt 90 .

As shown in FIG. 6, the connector 100 includes a connector main body 101 and a pair of holding portions 102 and 103 which are continuously provided on the connector main body 101 and formed to hold a heater 60 and a holder 70 therebetween. do. The holding portion 102 is electrically connected to a terminal T1 and a terminal T2 of the power supply terminal T of the heater 60 when the connector 100 is attached to the heating unit 51 so as to hold the heater 60 and the holder 70 therebetween. One electrode 104 is provided. The connector 100 can supply power to the heater 60 via the electrodes 104 .

As shown in FIGS. 7 and 8, in the fixing device 45 of this embodiment, the wire spring 110 is configured using, for example, a conductive metal wire. The wire spring 110 extends from a first opposing portion 111 that faces the first surface 60A of the heater 60 and supports the first surface 60A, and one end of the first opposing portion 111, and extends from one end of the heater 60 in the width direction SH. A first engaging portion 112 that engages the holder 70 on the end portion side, and a second engaging portion that extends from the other end portion of the first opposing portion 111 and engages the holder 70 on the other end portion side in the width direction SH. and a joint portion 113 . In the fixing device 45 of this embodiment, the second engaging portion 113 of the first engaging portion 112 and the second engaging portion 113 functions as an engaging portion that engages the substrate S and the holder 70 .

Specifically, the first engaging portion 112 is continuous with one end of the first opposing portion 111 and extends perpendicularly to the thickness direction of the holder 70 from one end of the first opposing portion 111 . It includes a first extension portion 112A and a first bent portion 112B that is continuous with the first extension portion 112A and is bent from the first extension portion 112A toward the first opposing portion 111 side.

Similarly, the second engaging portion 113 continues to the other end of the first facing portion 111 and extends perpendicularly to the thickness direction of the holder 70 from the other end of the first facing portion 111 . It has an extended portion 113A and a second bent portion 113B which is continuous with the second extended portion 113A and is bent from the second extended portion 113A toward the first facing portion 111 side.

In the wire spring 110, when the wire spring 110 is assembled to the heating unit 51, as shown in FIG. At the same time, the first engaging portion 112 is inserted into the mounting hole 70</b>D formed in the holder 70 while being elastically deformed. In the wire spring 110, the other end of the first opposing portion 111 is arranged in the holder side groove 70E formed in the holder 70, and the second engaging portion 113 is formed in the holder 70 in a state of being elastically deformed. is inserted into the mounting hole 70F.

Further, the second engaging portion 113 is arranged in the groove 60C including the substrate-side groove SA, the grooves Z1A, Z2A, and Z3A of the heater 60, and engages with the groove 60C. That is, the second engaging portion 113 is configured to engage with the holder side groove 70E, the substrate side groove SA facing the holder side groove 70E, and the mounting hole 70F, thereby positioning the wire spring 110 with respect to the holder 70. configured to be able to

In the wire spring 110, since the second engaging portion 113 is engaged with the substrate S of the heater 60, the wire spring 110 comes into contact with the side surface of the substrate S, and the wire spring 110 acts as a grounding member (not shown). The substrate S is configured to be electrically groundable through the ground.

As described above, the fixing device 45 and the image forming apparatus 1 using the fixing device 45 of the present embodiment include the wire spring 110 as a fastening member for fastening the heater 60 to the holder 70 so that the heater 60 is held by the holder 70, and a connector 100 for supplying power to the heater 60 . The wire spring 110 has a second engaging portion 113 as an engaging portion that engages with the substrate S of the heater 60 and the holder 70 at the end portion in the width direction SH orthogonal to the longitudinal direction LH of the heater 60 . Therefore, in the fixing device 45 and the image forming apparatus 1 of the present embodiment, even when the substrate S made of a metal material is used for the heater 60, the heater 60 can be held by the holder 70 without any positional deviation. Become. As a result, in the present embodiment, the fixing device 45 and the image forming apparatus 1 are configured to suppress the occurrence of misalignment between the heater 60 and the connector 100 even when the substrate S made of a metal material is used for the heater 60. can do.

In addition, in the present embodiment, it is possible to suppress the occurrence of positional displacement between the heater 60 and the connector 100 , so that there is a gap between the heater 60 and the connector 100 caused by relative positional displacement between the heater 60 and the connector 100 . It is possible to suppress the occurrence of electrical contact failure, and it is possible to suppress the shortage of power supply to the heater 60, thereby suppressing the deterioration of the heating power of the heater 60 and the deterioration of the fixing performance. can.

Further, in the present embodiment, the second engaging portion 113 of the first engaging portion 112 and the second engaging portion 113 allows the heater 60 and the connector to be connected even when the substrate S made of a metal material is used for the heater 60 . Since the occurrence of positional deviation with respect to 100 is suppressed, the longitudinal lengths of heater 60 and holder 70 can be shortened. In other words, a comparative example is conceivable in which the occurrence of positional deviation between the heater 60 and the connector 100 is suppressed by providing a convex portion and a concave portion to be fitted thereto on one and the other of the substrate S and the holder 70, respectively.

However, in the comparative example as described above, the dimension in the longitudinal direction LH of the projections and recesses is made larger than the dimension in the longitudinal direction LH of the wire spring 110 in order to reliably suppress the occurrence of positional deviation. There is a need. As a result, in this embodiment, the longitudinal lengths of the heater 60 and the holder 70 can be shortened compared to the comparative example, and the cost of the fixing device 45 and the image forming apparatus 1 can be easily reduced. can be done.

Further, in this embodiment, the holder 70 has the mounting hole 70F into which the second engaging portion 113 is inserted. can be engaged with the holder 70 .

Further, in this embodiment, the holder 70 has the holder side groove 70E with which the second engaging portion 113 is engaged. 110 can be positioned relative to holder 70 .

Further, in this embodiment, the substrate S has the substrate side groove SA facing the holder side groove 70E. It can be positioned relative to holder 70 .

Further, in this embodiment, the wire spring 110 has conductivity, and at least the second engaging portion 113 abuts the side surface of the substrate S. As shown in FIG. Thereby, in this embodiment, the substrate S can be electrically grounded. As a result, in the present embodiment, even if the heater 60 generates heat or stops causing thermal expansion or thermal contraction in the longitudinal direction LH, the substrate S can be stably and appropriately grounded.

In this embodiment, the shortest distance between the wire spring 110 and the belt 90 is smaller than the shortest distance between the connector 100 and the belt 90. Even when static electricity is charged due to contact with the inner peripheral surface 90</b>A of the wire spring 110 , the wire spring 110 can neutralize the belt 90 while suppressing discharge to the connector 100 .

Further, in this embodiment, since the wire spring 110 is arranged between the connector 100 and the belt 90 , when the belt 90 is charged, the wire spring 110 can reliably neutralize the belt 90 .

Also, in the above description, the case where the connector 100 and the wire spring 110 are provided on one end side of the longitudinal direction LH of the heater 60 has been described, but the present embodiment is not limited to this, and the connector 100 and the wire spring are not limited to this. Each of the 110 may be arranged on at least one of one end side and the other end side of the heater 60 in the longitudinal direction LH. However, the case where the connector 100 and the wire spring 110 are provided on the same side in the longitudinal direction LH is preferable in that the occurrence of positional deviation between the heater 60 and the connector 100 can be more reliably suppressed. .

[Embodiment 2]
Other embodiments of the present disclosure are described below. For convenience of description, members having the same functions as those of the members described in the above embodiments are denoted by the same reference numerals, and description thereof will not be repeated.

FIG. 9 is a cross-sectional view showing a main configuration example of a fixing device included in the image forming apparatus according to Embodiment 2 of the present disclosure.

In the figure, the difference between the present embodiment and the first embodiment is that engaging portions for engaging the substrate S and the holder 70 are provided at both ends of the heater 60 in the width direction SH.

As shown in FIG. 9, in the fixing device 45 of this embodiment, the heater 60 is provided with a groove 60D. Like the groove 60C, the groove 60D includes a substrate side groove provided in the substrate S and facing the holder side groove 70C, and formed in the first insulating layer Z1, the second insulating layer Z2, and the third insulating layer Z3. grooves and grooves.

In addition, in the fixing device 45 of the present embodiment, not only the second engaging portion 113 but also the first engaging portion 112 functions as an engaging portion that engages the substrate S and the holder 70 . That is, the first engaging portion 112 is configured to engage with the holder side groove 70C, the board side groove facing the holder side groove 70C, and the mounting hole 70D, thereby positioning the wire spring 110 with respect to the holder 70. configured to be able to

With the above configuration, the image forming apparatus 1 of the present embodiment has the same effects as those of the first embodiment. Further, in the image forming apparatus 1 of the present embodiment, since the first engaging portion 112 and the second engaging portion 113 are engaged with the heater 60 and the holder 70 including the substrate S, the heater 60 and the holder 70 are In contrast, the wire spring 110 can be fixed more firmly, and the occurrence of positional deviation between the heater 60 and the connector 100 can be more reliably suppressed. In addition, since the first engaging portion 112 and the second engaging portion 113 of the wire spring 110 are in contact with the side surfaces of the substrate S on both one side and the other side in the width direction of the heater 60, the substrate S can be held more firmly. It can be stably grounded.

In the above-described embodiment, the wire spring 110 is used as a fixing member for fixing the heater 60 to the holder 70 so that the heater 60 is held by the holder 70, but the present invention is not limited to this. For example, the heater 60 may be fastened to the holder 70 using a plate-shaped clip as a fastening member. In this case, the plate-shaped clip may function as an engaging portion that engages the substrate S and the holder 70 .

The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims, and configurations obtained by appropriately combining technical means disclosed in each embodiment It is included in the technical scope of the present disclosure.

Reference Signs List 1 Image forming apparatus 60 Heater S Substrate SA Substrate side groove P Resistance heating element 70 Holder 70D, 70F Mounting holes 70C, 70E Holder side groove 90 Belt 90A Inner circumferential surface 100 Connector 110 Wire spring (fixing member)
111 first facing portion 112 first engaging portion 113 second engaging portion LH longitudinal direction SH width direction

Claims (10)

A heater having a substrate made of a metal material and a resistance heating element disposed on the substrate;
a holder that holds the heater;
a fastening member that fastens the heater to the holder so that the heater is held in the holder; and a connector that supplies power to the heater;
The fastening member is arranged on at least one side of one end side and the other end side in the longitudinal direction of the heater,
The connector is arranged on at least one of the one end side and the other end side of the heater,
The fixing device, wherein the fastening member has an engaging portion that engages with the substrate and the holder at an end portion in a width direction orthogonal to a longitudinal direction of the heater. The fastening member
a first facing portion that faces the first surface of the heater and supports the first surface;
a first engaging portion that extends from one end of the first opposing portion and engages the holder at one end in the width direction;
a second engaging portion extending from the other end of the first opposing portion and engaging with the holder at the other end in the width direction;
2. The fixing device according to claim 1, wherein the engaging portion is at least one of the first engaging portion and the second engaging portion and engages with the substrate. The fixing device according to claim 2, wherein the fastening member is a wire spring. 4. The fixing device according to claim 1, wherein said holder has a mounting hole into which said engaging portion is inserted. The fixing device according to any one of claims 1 to 4, wherein the holder has a holder side groove with which the engaging portion is engaged. 6. The fixing device according to claim 5, wherein the substrate has a substrate groove that faces the holder groove and engages with the engaging portion. The fixing device according to any one of claims 1 to 6, wherein the fastening member has conductivity, contacts a side surface of the substrate, and electrically grounds the substrate. further comprising an endless belt whose inner peripheral surface is in contact with the heater,
8. The fixing device according to claim 7, wherein the shortest distance between said fastening member and said belt is smaller than the shortest distance between said connector and said belt. The fixing device according to claim 8, wherein the fastening member is arranged between the connector and the belt. An image forming apparatus comprising the fixing device according to claim 1 .

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