JP2002267543A - Temperature detecting unit and heating device having temperature detecting unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent wrong assembling of an externally fitted temperature detecting unit, to realize stable temperature detecting performance, and to reduce the cost by decreasing the number of parts. SOLUTION: In this temperature detecting unit structure, a temperature detecting member 100 has a temperature detecting element part 100j at the tip of a plate spring 100h, the member 100 and a holding member 2 are put in the fitting state by a fitting shaft 2b and a fitting hole 100i, so that in assembling, the force of the spring is shifted in the direction oblique to the fitting shaft 2c to provide temporary stopping action, thereby pressing the holding part 100i of the temperature detecting member to a member 1 to be detected about the temperature. At the completion of assembling a positioning member 5a of its structure 5 and a butting part 100c of the temperature detecting member, or in its use, the direction of spring force is made parallel to the fitting shaft, so that the positioning part and the butting part strike each other, thereby positioning the member to be detected about the temperature in the direction of thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a temperature detecting unit and a heating device having the temperature detecting unit.

[0002]

2. Description of the Related Art For convenience, in an image forming apparatus such as an electrophotographic copying machine or a printer, a recording material having an unfixed image to be fixed and conveyed from a recording unit is heated to convert the unfixed image to a recording material. An example of a film heating type heating device used as a heat fixing device for fixing will be described.

[0003] As a heat fixing device of the film heating type, there is, for example, a tension-free type device disclosed in JP-A-4-44075-44083 and JP-A-4-204980-204984. This has a pressurizing rotator that contacts and moves a heat-resistant film to a heating element, moves the film, presses against the opposite side of the film from the heating element, and rotates. The recording material having an unfixed image to be image-fixed from the recording unit of the image forming apparatus is supplied to the press contact portion formed between the recording material and the press contact portion is nipped and conveyed by the driving force of the pressing rotator to form a film. And heat-fixes the unfixed image to the recording material by the heat of the heating element.

FIG. 7 is a schematic cross-sectional view of an essential part of an example of a film fixing type heat fixing device. 1
Is a ceramic heater as a heating element. The ceramic heater 1 is a heater fitting groove 2a formed along the length of a heater holder 2 having rigidity and heat insulation.
It is fitted inside and fixedly supported. The heater holder 2 also serves as a guide for sliding the fixing film 3 described later. The material of the heater holder 2 is a thermoplastic resin having good moldability and low cost.

Reference numeral 3 denotes a cylindrical (endless belt-shaped) heat-resistant film (fixing film) loosely fitted to the heater holder 2 on which the heater 1 is fixedly supported as described above. This film 3 usually has a film thickness of 10 to reduce the heat capacity and improve the quick start property.
It is composed of a composite film in which PTFE, PFA, FEP is coated as a release layer on the surface of a film of polyimide or the like having heat resistance of 0 μm or less, releasability and durability.

Reference numeral 4 denotes an elastic pressure roller made of heat-resistant rubber as a pressure rotating body that forms a nip N (heating nip portion, fixing nip portion) between the film 3 and the heater 1 with the film 3 interposed therebetween.

Reference numeral 5 denotes a reinforcing stay, which is a U-shaped rigid member having a downward cross-section, which is placed inside the heater holder 2.

The fixing film 3 is slid and conveyed at a predetermined speed in the clockwise direction of the arrow a by being in close contact with the lower surface of the heater 1 by the driving roller M rotating the pressure roller 4 in the counterclockwise direction of the arrow. You.

When the heater 1 is energized to raise the temperature to a predetermined fixing temperature, temperature is controlled, and the fixing film 3 is being conveyed, the fixing roller 3 is moved between the fixing film 3 and the pressure roller 4 in the fixing nip N. Then, a recording material P to be image-fixed as a heated material from a recording unit of an image forming apparatus (not shown) is introduced into the fixing nip N together with the fixing film 3.
, The heat of the heater 1 is applied to the recording material P via the fixing film 3 to heat and fix an unfixed image (toner image) t on the surface of the recording material P.

The recording material P that has passed through the fixing nip portion N is conveyed from the surface of the fixing film 3 with its curvature sequentially separated.

Incidentally, in recent years, as the speed of the image forming apparatus has increased, it has become necessary to increase the control temperature even in the heat fixing apparatus having the above-described configuration. Along with this, in order to prevent the heating and fixing device from being damaged due to a rise in the temperature of the non-sheet-passing section, the heater is more finely controlled, so that it is different from the conventional control temperature detection means mounted on the heater. Is provided with an external temperature detecting means. Alternatively, the control temperature of the heater becomes high, and the fixing adhesive of the conventional mounted control temperature detecting means cannot be used, so that an external temperature detecting means is unavoidably provided in some cases.

FIG. 8 is an exploded perspective view showing the configuration of such an external temperature detecting means.

The temperature detecting member 100 as an external temperature detecting means is roughly divided into a fixing portion (holding portion) 100i.
And a temperature sensing element 100j attached to the tip of the leaf spring 100f.

A fitting hole 100 provided in the fixing portion 100i
1A, the heater 1 is positioned in the plane direction. As a fixing method, the temperature detection member 100
The push nut 101 is inserted into and fixed to the fitting boss 2b of the heater holder 2 in a state where the fixing portion 100i is in abutment.

The temperature detecting element 10 of the temperature detecting member 100
No. 0j comes into contact with the back surface of the heater 1 attached to the heater holder 2 through the square hole 2c provided in the heater holder 2, and before the heater 1 is attached to the heater holder 2, the temperature detection element portion 100j Is in contact with the outer frame 2d of the square hole 2c so that the temperature sensing element 100j can be seen through the square hole 2c.

Thereafter, the heater 1 is set on the heater holder 2, a predetermined pressing force is applied to the heater holder 2 via the reinforcing stay 5, and the heater 3 and the pressure roller 4 are pressed against each other with the film 3 interposed therebetween. When the nip portion N is formed, the temperature detecting element 100j of the temperature detecting member 100 and the back surface of the heater 1 come into contact with each other at a predetermined contact pressure due to the elasticity of the leaf spring 100f, and the temperature of the heater 1 by the temperature detecting element 100j. It is in the state where detection is performed.

[0017]

However, in such a temperature detecting member 100 as an external temperature detecting means, even if the push nut 101 is forgotten to be attached due to a mistake in assembling the heating device, the tip of the temperature detecting element portion 100j is not required. When the extension portion 100k is in contact with the square hole outer frame portion 2d, a leaf spring pressure acts obliquely to the axial direction of the fitting shaft 2b. At the fitting part, since it is temporarily fixed in a state like a temporary fix, assembly continues without being noticed as it is, the inspection passes, the assembly is completed, the contact pressure gradually decreases, and it does not operate properly However, there has been a problem that erroneous temperature detection occurs.

Further, even when the push nut 101 is installed without fail, the manner in which the temperature detecting member 100 abuts and the position where the push nut 101 is pushed in vary depending on the operator. There is also a problem that the contact pressure of the sensing element unit 100j with the heater 1 varies, and a stable operation of the temperature sensing member 100 cannot be ensured.

Accordingly, an object of the present invention is to prevent erroneous assembly of an external temperature detecting unit, realize stable temperature detecting performance, and reduce costs by reducing parts.

[0020]

SUMMARY OF THE INVENTION The present invention is a temperature detecting unit and a heating apparatus having the temperature detecting unit, which are characterized by the following constitution.

(1) A temperature detecting member having a temperature detecting element at the tip of a spring member which is a biasing member whose direction of force changes depending on the amount of deflection, a holding member for holding the temperature detecting member,
A structure having rigidity between the pressing member when pressing the holding member including the temperature detection member against the temperature detection member,
A pressure member that presses a holding member including a temperature detection member against a temperature detection member with at least a pressure greater than a pressure of a spring member of the temperature detection member, and a temperature detection unit having a temperature detection member detected by the temperature detection member , The temperature detection member has a fitting hole or a fitting shaft for positioning the temperature detection member in the surface direction, and an abutting portion for positioning the temperature detection member in the height direction. The member has a fitting shaft or a fitting hole for positioning in the surface direction of the temperature detecting member, and an opening for the temperature detecting element portion of the temperature detecting member to come into contact with the temperature-detected member. In addition, a positioning portion having a predetermined gap for contacting and holding a height abutting portion of the temperature detecting member other than a contact portion with the holding member is provided, and the temperature detecting member is fitted to the holding member at the time of assembly. Mounted with In this case, a part of the temperature detecting member abuts on the outer edge of the opening hole of the holding member, and the direction of the force by the spring member of the temperature detecting member at this time is configured to be oblique to the mounting direction of the fitting hole and the shaft. When the assembly is completed and the structure is pressed by the mounting pressing member and the temperature detecting member comes into contact with the temperature detected member, the direction of the force by the spring member of the temperature detecting member is in the mounting direction of the fitting hole and the shaft. The temperature sensing member and the temperature sensing member are configured to be parallel to each other, and the abutting portion of the temperature sensing member is abutted against the positioning portion of the structure and fixed at a predetermined contact pressure. Characteristic temperature detection unit.

(2) a heat-resistant film in the form of an endless belt, a heating element disposed inside the film, a heating element holding member made of a heat-insulating resin that holds the heating element and also serves as a film guide; A stay having rigidity for uniformly pressing the heating element holding member including the heating element in contact with the back surface of the heating element holding surface, and forming a pressure contact nip portion between the heating element and the film, and A pressurizing rotator that rotates the film in the direction of conveying the material to be heated at a predetermined speed while sliding the inner surface of the film against the surface of the heating body, and between the outer surface of the film and the pressurizing rotator of the press-contact nip portion. In a heating device of a film heating type in which the heat energy of the heating body is applied to the material to be heated through the film by introducing and moving the material to be heated through the pressure nip portion together with the film,
The temperature detection unit according to (1) above, wherein the temperature detection member is the heating body, the holding member is the heating body holding member, and the structure is the stay. A heating device, characterized in that:

(3) The heater is a substantially flat heater made of a base material that is electrically insulated and has high thermal conductivity, and the heater holding member holds the heater and is made of a thermoplastic resin having good heat insulation. The heating device according to (2), wherein the stay is a holder, the stay being attached to the back side of the heater holding surface of the heater holder, the stay having rigidity, and made of a sheet metal for equally pressing the heater holder.

(4) The heating device according to (2) or (3), wherein the material to be heated is a recording material carrying an unfixed image, and the unfixed image is heated and fixed to the recording material. .

<Operation> That is, a temperature detecting member having a temperature detecting element portion at a tip end of a spring member, and a holding member is fitted with a fitting shaft and a fitting hole. The structure has a structure for pressing the holding portion of the temperature detection member against the temperature detection member, and has a structure in which the direction of the force of the spring member is shifted obliquely from the fitting axis and has a temporary fixing action. When the positioning portion and the abutting portion of the temperature detecting member are assembled and used, the direction of the force of the spring member is in a direction parallel to the fitting axis, so that the positioning portion and the abutting portion abut and the thickness of the temperature-sensing member is reduced. With the temperature detection unit structure that positions in the direction, it is possible to perform temporary fixing such as temporary fixing even when assembling the temperature detection member before attaching the temperature detection member (heater). Temperature detection After the completion of the assembly including the mounting of the members, since the temperature detecting member can be positioned in the thickness direction at a predetermined position of the positioning portion of the structural body (reinforcing stay), the temperature detecting member and the temperature detecting member are always stable. It is possible to realize a temperature detection unit in which the contact pressure is ensured.

Further, since the assembling can be performed without using a separate fixing member, the system is advantageous in terms of cost, avoids the possibility of operator error, and provides a stable quality temperature detecting unit and temperature. This leads to the realization of a heat fixing device having a detection unit.

[0027]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic cross-sectional view of a heating device provided with a temperature detecting unit according to the present invention. The heating device of this embodiment is a film fixing method, a heating roller driving method, and a tensionless type heat fixing device as in FIGS. 7 and 8 described above. Is omitted.

FIG. 2 is a longitudinal sectional model view of an external temperature detecting member 100 mounted on the apparatus, FIG. 3 is an exploded perspective view of a main part, FIG. 4 is a structural view of the heater 1, and FIG. FIG. 6 is a structural diagram of the temperature detecting member 100, and FIG.
FIG. 3 is a state diagram of a state in which is attached to a heater holder 2 (before the heater is attached).

1) Heater 1 (Temperature Detecting Member) First, the structure of the ceramic heater 1 as a heating element in this embodiment will be described with reference to FIG. (A) is an enlarged cross-sectional model diagram of the heater 1, (b) is a partially cutaway plan model diagram of the heater front side, and (c) is a plan model diagram of the heater back surface side.

The ceramic heater 1 as a heating element in the present embodiment is an elongated flat plate-shaped member having an insulating low heat capacity. The heater 1 uses aluminum nitride (AlN) having a thermal conductivity that is about 10 times higher than that of alumina as the heater substrate 1a, and energizes the substrate surface side (heater surface side) which is the film / recording material heating surface side. Heating resistor 1
b and the electrode portion 1c, and the energized heating resistor 1b is covered with a surface protective layer 1f made of heat-resistant glass. A surface heating type / one-side back electrode pattern heater in which a substrate temperature detecting element 1d (thermistor) and its electrode portion 1e are provided on the reverse side of the substrate (heater rear side).

When power is supplied from a power supply circuit (not shown) to the power-generating resistor 1b via the electrode 1c, the temperature of the entire heater 1 rapidly rises.

The thermistor 1d provided on the back surface of the heater 1 is provided at a location which is located in the area where the small-sized paper, for example, A5-size paper passes, even if the paper passes. The data is input to a temperature control circuit (not shown) via the electrode 1e. In the temperature control circuit, the power supply from the power supply circuit to the energizing heating resistor 1a is controlled so that the temperature detected by the thermistor 1d is maintained at a predetermined fixing temperature. That is, the thermistor 1d becomes the main and controls the temperature of the heater 1.

2) Temperature detecting member 100 An external temperature detecting member (hereinafter referred to as a sub thermistor)
Reference numeral 100 denotes the temperature detection element unit 100j, which is located outside the passing area of small-size paper, for example, A5 paper, and at a distance L from the center in the passing area of LTR-size paper.

The sub thermistor 100 detects the temperature of the heater 1 separately from the main thermistor 1d and feeds it back to a control circuit (not shown). This sub-thermistor 100 is used, for example, when continuous paper of A5 size is continuously passed and the temperature is likely to rise sharply in the non-paper passing area of the heater 1 (excessive temperature rise in the non-paper passing portion). This is used for controlling the heat fixing device to prevent the heat fixing device itself from being damaged at the time when the paper is passed or at intervals.

FIG. 5 is a schematic diagram showing the structure of the sub thermistor 100. (A) is a schematic side view and (b) is a schematic bottom view.

The sub-thermistor 100 is roughly divided into a holding section (fixing section) 100i for positioning and holding, a temperature detecting element section 100j having a temperature detecting element 100e and detecting the temperature by contacting the heater 1; Sensing element unit 10
It is composed of three leaf spring portions 100h made of leaf springs for urging the heater 1 with 0j at a predetermined contact pressure.

The holding unit 100i includes a sub thermistor 10
0, a fitting hole 1 fitted with a fitting shaft 2b of a heater holder 2 for positioning and holding the heater 1 in a planar direction.
00a is provided, and a boss 1 for stopping rotation is provided in the vicinity thereof.
00b is provided. An abutting portion 100c that abuts a positioning portion 5a of the reinforcing stay 5 described later.
Are provided on both sides.

The temperature detecting element 100j is a leaf spring 10
Frame 1 fixed to the tip of 0h by insert molding
00d, temperature detecting element 100e, and temperature detecting element 100e
A heat insulating sponge 100f having a cushioning property for causing the heater 1 to follow the heater 1 and an insulating tape 100g wound around the outside of the temperature detecting element 100e.

The leaf spring portion 100h is used when the heater 1 is used.
Two leaf springs, each of which has a U-shape, are attached side by side so that a force is applied in a direction perpendicular to the axis and in a direction parallel to the axial direction of the fitting shaft 2b of the heater holder 2. This leaf spring is made of stainless steel and also serves as a conduction path for the temperature detecting element 100e.

3) Heater Holder 2 (Holding Member for Temperature Detecting Member) The heater holder 2 is a member having rigidity and heat resistance, for example, made of a material such as a liquid crystal polymer. The heater 1 is a horizontally elongated member having a substantially semicircular gutter shape, and the heater 1 is supported by being fitted in a fitting groove 2a (FIG. 1) formed along the lower surface of the heater holder 2 along the longitudinal direction.

On the side opposite to the heater supporting surface of the heater holder 2, the temperature detecting element 1 of the sub thermistor 100
A fitting shaft 2b is provided for holding 00j at a position corresponding to outside the small-size sheet passing area.

The sub thermistor 1 is located near the fitting shaft 2b.
An opening square hole 2c is provided for the temperature sensing element portion 100j of No. 00 to contact the heater 1. The opening square hole outer frame portion 2d with which the tip extension portion 100k of the temperature detecting element portion 100j contacts is lower by one step. In addition, sub thermistor 1
A hole 2g for stopping rotation of 00 is also provided near the fitting shaft.

4) Reinforcement stay 5 (rigid structure) The reinforcement stay 5 (rigid structure) is a horizontally long iron-shaped rigid member having a downward U-shaped cross section, and a portion that comes into contact with the heater holder 2. Is required to have a high precision, and therefore, is not a continuous surface, but has a shape as shown in FIG. Using a part of the flank, there is provided a positioning portion 5a which abuts against an abutting portion 100c provided in the holding portion 100i of the sub thermistor 100.

The positioning portion 5a is designed so that the abutting portion 100c of the sub thermistor 100 comes into contact only when all assembly is completed and a pressing force greater than the urging force of the leaf spring 100h of the sub thermistor 100 is applied. When the reinforcing stay 5 and the heater holder 2 are initially brought into contact with each other, a predetermined gap is formed.

5) Assembling of Sub-Thermistor 100 FIG. 6 is a cross-sectional view in the longitudinal direction of the heater, showing an initial state of assembling the sub-thermistor 100.

When the fitting hole 100a of the holding portion 100i of the sub thermistor 100 is assembled through the fitting shaft 2b of the heater holder 2, the tip of the tip extension portion (leaf spring tip portion) 100k of the temperature detecting element portion 100j is Heater holder 2
Contact the outer frame portion 2d of the opening square hole 2c of FIG. Incidentally, the shape of the sub thermistor alone is shown by a two-dot chain line. At this time, since a force is applied to the spring 100h in the direction of arrow A, the direction of the fitting shaft 2b is an oblique direction having an angle θ. For this reason, a force component is also generated in a direction perpendicular to the axial direction.
00 is held, and a state like temporary fixing is maintained. As a result, the sub-thermistor 100 can be temporarily fixed without being fixed by another stopper member, so that the assembly can be performed with a relatively high degree of freedom thereafter.

In this state, the reinforcing stay 5 is placed inside the heater holder 2 and disposed, and the cylindrical film 3 is further attached to the heater 1, the heater holder 2 and the reinforcing stay 5 assembly. With a margin in the circumference to fit loosely. The shafts at both ends of the pressure roller 4 are rotatably supported and arranged, and the heater 1, the heater holder 2, the film 3,
An assembly made of the reinforcing stays 5 and the like are opposed to each other with the heater 1 side facing downward, and both ends of the reinforcing stays 5 are pressed downward by pressurizing spring members (not shown). And the pressure roller 4 are pressed against each other with the film 3 sandwiched therebetween against the elasticity of the pressure roller 4.
A heating nip portion (fixing nip portion) N having a predetermined width is formed.

FIG. 1 is a cross-sectional view of the heating / fixing apparatus in this state near the sub thermistor 100 in the short direction of the heater.
FIG. 2 is a cross-sectional view in the longitudinal direction of the heater showing a state around the sub thermistor at this time.

According to this, the force of the leaf spring 100h of the sub thermistor 100 is perpendicular to the heater 2 and parallel to the axial direction of the fitting shaft 2b of the heater holder 2, and is applied by a pressing spring (not shown). Since the pressing force is much larger than the urging force of the leaf spring 100h of the sub thermistor 100, the abutting portion 100c of the sub thermistor 100
Abuts against the positioning portion 5a of the reinforcing stay 5, and positioning in the heater thickness direction is performed. At this time, the holding portion 100i of the sub thermistor 100 is positioned with a predetermined gap G (FIG. 2) secured between itself and the heater holder 2.

Since the positioning of the sub-thermistor 100 in the thickness direction of the heater is performed as described above, the positioning of the sub-thermistor 100 is always performed at a stable position.
As a result, the performance of the sub thermistor 100 becomes stable.

Further, since another fixing member such as the push nut 101 (FIG. 8) is not required, it is possible to prevent a device failure due to an assembly error.
Stable quality can be realized without impairing the assemblability.

In this embodiment, the external temperature detecting member 10
0 is a sub thermistor in the non-sheet passing area. However, the position and function are not limited to this. For example, an external temperature detection function that performs the position and function of the main thermistor mounted on the heater Even if it is a member, the same effect of the invention can be obtained.

In this embodiment, the temperature detecting member 100
The side is the fitting hole 100a and the holding member 2 side is the fitting shaft 2b. However, if the fitting length can be secured to some extent, the temperature detecting member 100 side is the fitting shaft and the holding member 2 side is the fitting hole. Even if it does, the same effect of the invention can be obtained.

In the present embodiment, the abutting in the heater thickness direction is performed by the abutting portions 100c provided on both sides of the temperature detecting member 100 and the positioning portion 5a which is one step away from the reinforcing stay 5. The same effect can be obtained even if it is a configuration in which accurate positioning is possible even if the abutting portion of the top surface portion of the detection member 100 and the arc surface inside the reinforcing stay are used.

Thus, in this embodiment, a. The holding portion (fixed portion) 100i of the temperature detecting member 100 has a fitting hole 100a or a fitting shaft for positioning the temperature detecting member 100 in the surface direction of the heater 1, and for positioning the heater in the thickness direction. Butting part 10
0c, b. The heater holder 2 (holding member of the temperature detecting member) has a fitting shaft 2 b or a fitting hole for positioning the temperature detecting member 100 and the temperature detecting element portion 10 of the temperature detecting member 100.
0j has an opening 2c for contacting the heater 1, c. The reinforcing stay 5 (a structure having rigidity) has a protrusion having a predetermined gap for contacting a contact portion 100c for positioning the temperature detection member 100 in the heater thickness direction in addition to the contact portion with the heater holder 2. Providing a contact positioning portion 5a; d. When assembling the temperature detecting member 100 before mounting the heater, the temperature detecting element portion 100j of the temperature detecting member 100
Of the temperature detecting member 100 is brought into contact with the outer extension 2d of the opening hole of the heater holder 2.
0i is applied to the fitting shaft 2b in which the heater holder 2 is fitted in a diagonal direction, and when assembly including mounting of the heater is completed, the holding portion 100i of the temperature detection member 100 is perpendicular to the heater 1 and Heater holder 2
Has a leaf spring shape in which a force is applied in a direction parallel to the fitting shaft 2d to which the temperature detecting member 10d is fitted.
0 abutting portion 100c and positioning portion 5 of reinforcing stay 5
a, the temperature detecting member 100 is positioned in the thickness direction of the heater by contact with the a, so that the temperature detecting member 100 can be temporarily fixed as a temporary fix even when the temperature detecting member 100 is assembled before the heater 1 is attached. Since the assemblability is good and after the completion of the assembly including the mounting of the heater 1, the temperature detecting member 100 can be positioned in the heater thickness direction at a fixed position of the positioning portion 5a of the reinforcing stay 5, so that the temperature detecting element It is possible to realize a temperature detection unit in which a stable contact pressure between the unit 100j and the heater 1 is always secured, and a heat fixing device having the temperature detection unit.

Further, since the assembling can be performed without using another fixing member, the system is advantageous in terms of cost, avoids the possibility of operator error, and has a stable quality temperature detecting unit and temperature. This leads to the realization of a heat fixing device having a detection unit.

6) Others The heating device having the temperature detection unit according to the present invention is not limited to the film heating type heating and fixing device of the embodiment. In addition, for example, an image heating device that heats a recording material carrying an image to improve surface properties such as gloss, an image heating device that performs a hypothetical deposition process, feeds a sheet-like material, and performs a drying process, a lamination process, and a wrinkle removal Of course, it can be widely used as a heating device for performing a hot press process, a heating device for drying used in an ink jet printer, or the like.

[0059] The configuration of the heating device to which the temperature detection unit according to the present invention is applied is not limited to the film heating type device of the embodiment.

[0060] The temperature detection member is not limited to the ceramic heater as in the embodiment. For example, other heat sources, such as an electromagnetic induction heating member and a halogen heater, and members heated by those heat sources may be used.

[0061]

As described above, according to the present invention,
Prevents erroneous assembly of the external temperature detection unit, achieves stable temperature detection performance, and reduces costs by reducing parts.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a heating device according to an embodiment.

FIG. 2 is a vertical cross-sectional model view of an external temperature detecting member portion attached to the device.

FIG. 3 is an exploded perspective view of an essential part of the heating device.

FIG. 4 is a structural view of a heater.

FIG. 5 is a structural diagram of a temperature detecting member.

FIG. 6 is a view showing a state where the temperature detecting member is attached to the heater holder (before attaching the heater).

FIG. 7 is a schematic configuration diagram of a conventional heat fixing device.

FIG. 8 is an exploded perspective view around an external temperature detecting member.

[Explanation of symbols]

1 ------ Heater (Temperature detection member) 1d -------- Main thermistor 2 --------- Heater holder (Holding member) 2b----------------------------------------------------------------------------------------------------------------------------------- ------ Reinforcing stay (rigid structure) 5a ------------ Positioning part 100 ---------- Sub-thermistor (external temperature detecting member) 100a --- −−−− Mating hole 100h −−−−−−−−− Leaf spring 100c −−−−−−−−− Abutment part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05B 3/20 393 H05B 3/20 393 F term (Reference) 2F056 CE01 CL07 2H033 AA18 AA31 BA25 BA26 BA32 BE03 CA07 CA30 3K034 AA10 AA34 BA05 BA15 BB06 BC12 CA22 DA05 3K058 AA41 AA91 BA18 CA61 CE13 DA01

Claims (4)

[Claims] 1. A temperature detecting member having a temperature detecting element at a tip of a spring member which is a biasing member whose direction of force changes according to the amount of deflection, a holding member holding the temperature detecting member, and a holding member including the temperature detecting member. When pressing against the temperature-detected member, the structure having rigidity between the pressing member and the holding member including the temperature-detecting member is applied to the temperature-detected member with a pressure larger than at least the pressure of the spring member of the temperature-detecting member. In a temperature detection unit having a pressing member for pressing and a temperature detection member detected by the temperature detection member, the temperature detection member has a fitting hole or a fitting shaft for positioning the temperature detection member in the surface direction. And a butting portion for positioning the temperature detection member in the height direction. The holding member has a fitting shaft or a hole for positioning the temperature detection member in the surface direction, and a temperature of the temperature detection member. The sensing element unit has an opening for contacting the temperature detection member, and the structure is configured to contact and hold a height abutting portion of the temperature detection member in addition to the contact portion with the holding member. When the temperature detecting member is attached to the holding member at the time of assembling, a part of the temperature detecting member abuts the outer edge of the opening of the holding member, and the temperature at this time is determined. The direction of the force of the leaf spring of the detecting member is configured to be oblique to the mounting direction of the fitting hole and the shaft. When the assembly is completed, the structure is pressed by the pressing member so that the temperature detecting member detects the temperature to be detected. When in contact with the member, the direction of the force of the spring member of the temperature detecting member is configured to be parallel to the fitting direction of the fitting hole and the shaft, and the abutting portion of the temperature detecting member and the positioning portion of the structure are Thrust A temperature detection unit, wherein the temperature detection member and the temperature-detected member are in contact with each other and fixed at a predetermined contact pressure. 2. An endless belt-like heat-resistant film,
A heating element disposed inside the film, a heating element holding member made of a heat-insulating resin that holds the heating element and also serves as a film guide, and a heating element holding member including the heating element in contact with the back surface of the heating element holding surface A stay having rigidity for uniformly pressing the member, a press-contact nip portion is formed between the heating body and the heating body, and the film is moved to a predetermined position while sliding the inner surface of the film against the heating body surface. A pressurizing rotator that rotates in the conveying direction of the material to be heated, and introduces the material to be heated between the outer surface of the film of the press-contact nip portion and the pressurizing rotator to form a press-contact nip portion together with the film. A heating device of a film heating system for applying heat energy of a heating body to a material to be heated via a film by moving and passing the same, comprising the temperature detection unit according to claim 1, wherein in this case, the temperature detection is performed. A heating device, wherein a member is the heating body, the holding member is the heating body holding member, and the structure is the stay. 3. A heater holder in which a heating element is a substantially flat heater made of a base material that is electrically insulated and has high thermal conductivity, and a heating element holding member holds the heater and is made of a thermoplastic resin having good heat insulating properties. The heating device according to claim 2, wherein the stay is a stay that is attached to the back side of the heater holding surface of the heater holder and has rigidity and is made of a sheet metal for equally pressing the heater holder. 4. The heating apparatus according to claim 2, wherein the material to be heated is a recording material carrying an unfixed image, and the unfixed image is heated and fixed to the recording material.