JP2000058229A - Heating device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a good electric connection between an electrode and a contact on the side of a connector by providing at least one or more heater electrodes on a heater face, holding a conductive intermediate contact member, pinching the heater connector in the direction to crimp a heater and a heater holder, and electrically connecting the connector and the electrode via the intermediate contact member. SOLUTION: A conductive intermediate contact member 7 with flexibility (spring elasticity) has a nearly U-shape (clip shape) to follow three faces of the extended bulge sections 2b, 2c of a heater holder 2, and a contact portion 7a with an electrode on the side facing a heater 1 is formed into an R-shape and is made movable by a spring property. The heater 1 is temporarily held in a heater insertion groove 2a by a worker to be pressed to the heater holder 2 against the spring force of the intermediate contact member 7. A feeding heater connector 5 is fully coupled, inserted and assembled while the heater 1 is held on the heater holder 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrically insulative substrate, a heater which is basically composed of an electric heating resistor provided on the substrate, a heater holder for supporting the heater, The present invention relates to a heating device having a heater connector for making an electrical connection with a heater electrode and heating a material to be heated by the heat generated by the heater, and an image forming apparatus including the heating device as an image heating device.

[0002]

2. Description of the Related Art A heat fixing device used in an image forming apparatus such as a printer, a copying machine, a recording apparatus, a facsimile or the like, or an image recording apparatus, that is, a recording section for electrophotography or the like, corresponds to a recording material corresponding to target image information. For a device for forming and carrying an unfixed image and heating and fixing the same, as a system having a high heat transfer efficiency and a fast startup of the device, a fixedly supported low heat capacity thermal heater as a heating element,
Japanese Patent Application Laid-Open Nos. 63-313182, 2-157778, and 4-440 disclose a film heating type heating apparatus using a thin film that slides with the heater.
75-44083, JP-A-4-20498-0-2
No. 04984 has been proposed.

[0003] More specifically, a heat-resistant film is moved by bringing a heat-resistant film into contact with a substantially plate-shaped heating element, and a rotating pressurizing body is rotated by pressing against a side of the film opposite to the heating element side. A recording material having an unfixed image to be image-fixed is supplied from a recording unit to a press contact portion formed between the heating member and the pressurizing rotary member, and the press contact portion is nipped and conveyed by the driving force of the pressurizing rotary member. The unfixed image is heated and fixed on the recording material by the heat of the heating element.

FIG. 9 is a schematic cross-sectional view showing a schematic configuration of an example of a film heating type image heating apparatus (heating fixing apparatus). FIG. 10 is an enlarged model diagram of a heating nip portion, and FIG. 11 is an exploded perspective model diagram.

The apparatus of this embodiment is disclosed in Japanese Patent Application Laid-Open No. 4-44075-44.
No. 083 and the like, a film heating system using a cylindrical film, a pressure roller driving system, and a tensionless type heating device.

Reference numeral 10 denotes a heating assembly, which includes a ceramic heater 1A as a heating element, a heater holder 2, a cylindrical heat-resistant film (fixing film) 3, and a reinforcing stay 4.
And so on.

[0007] The ceramic heater 1A as a heating element is an elongated flat plate-shaped member having a low heat capacity and having a longitudinal direction perpendicular to the drawing in FIG. The specific structure of the heater 1A will be described later.

The heater holder 2 is a member having rigidity and heat resistance. The heater holder 2 of this embodiment is a trough-shaped member having a substantially semi-circular cross section, and the heater 1A is provided on the lower surface of the heater holder along the longitudinal direction. Heater fitting groove 2a formed and provided
It is fitted inside and fixedly supported.

The reinforcing stay 4 is a U-shaped horizontally-long rigid member having a downward cross-section, and is placed inside the heater holder 2 having a substantially semi-circular trough-shaped cross-section.

The cylindrical film 3 has the above-mentioned heater 1
A, the heater holder 2 and the reinforcing stay 4 are loosely fitted around the assembly with a margin in the circumferential length. The film 3 is usually formed by coating PTFE, PFA, FEP or the like as a release layer on a film surface of a polyimide or the like in order to reduce the heat capacity and improve the quick start property. It is composed of a composite layer film having both moldability and durability.

Reference numeral 11 denotes an elastic pressure roller as a pressure member, which comprises a metal core and a heat-resistant rubber elastic layer of silicon rubber or the like provided on the outside thereof. The pressure roller is arranged so that the shafts at both ends thereof are rotatably supported by bearings. Above the pressure roller 11, a heating assembly including the heater 1A, heater holder 2, film 3, reinforcing stay 4, and the like is provided. 10 are opposed to each other with the heater 1A facing downward, and both ends of the reinforcing stay 4 are pressed downward by a pressing spring member (not shown), so that the downward surface of the heater 1A and the pressing roller 11 are connected. The film 3 is sandwiched and pressed against the elasticity of the pressure roller 11 to form a heating nip portion (fixing nip portion) N having a predetermined width.

The driving force is transmitted from the driving source M to the pressing roller 11, and the pressing roller 11 is driven to rotate at a predetermined peripheral speed in a counterclockwise direction R indicated by an arrow (pressing roller driving type).

A rotational force acts on the film 3 by the frictional contact between the outer surface of the roller 11 and the outer surface of the film 3 due to the rotational driving of the pressure roller 11 at the heating nip portion N. Moves around the heater holder 2 clockwise at a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 11 while sliding in close contact with the downward surface of the heater 1A at the heating nip portion N in the clockwise direction indicated by an arrow.
To be driven and rotated. The heater holder 2 also serves as a rotation guide member for the cylindrical film 3.

In this case, the cylindrical film 3 which is driven to rotate around the outer periphery of the heater holder 2 has a circumferential nip portion N
And the film portions other than the film portion in the vicinity thereof are in a tension-free state (a state in which no tension is applied). In addition, a shift along the length of the heater holder 2 caused by the rotation of the film 3 causes the end of the film 3 to be received on the inner surface of a flange member (not shown) provided on the end side of the heater holder 2. Be regulated.

Thus, the pressure roller 11 is driven to rotate,
Along with this, the cylindrical film 3 is driven to rotate around the outer periphery of the heater holder 2, and the heater 1A is energized, and the temperature of the heating nip N rises to a predetermined level by the heat generated by the heater 1A, and the temperature is controlled. , A recording material P such as paper on which an unfixed visible image (unfixed toner image) t is formed and carried is introduced into the heating nip N, and the unfixed toner image of the recording material P is carried in the heating nip N. The surface side is in close contact with the outer surface of the film 3, and the heating nip N is conveyed together with the film 3.

In the process of nipping and transporting the recording material P,
The heat of the heater 1A is applied to the recording material P via the film 3, and the unfixed toner image t on the recording material P is heated and pressed to be fixed.

When the recording material P passes through the heating nip portion N, the recording material P is discharged and conveyed with a curvature separated from the outer surface of the film 3.

FIG. 12 (a) is a plan view of the heater 1A in which a part thereof is omitted and partly cut away, and FIG. 12 (b) is a plan view of the heater 1A in which a part thereof is omitted.

Ceramic heater 1A as heating element
Is a. Horizontal, thin, heat-resistant, low heat capacity, good thermal conductivity, electrical insulation with the longitudinal direction in the direction perpendicular to the moving direction a of the film 3 or the recording material P as the material to be heated in the heating nip portion N. Slender flat heater substrate 1a b. Energizing heat generating resistors 1b, 1b c. Which are formed along the longitudinal side of the surface of the heater substrate 1a (the surface facing the film 3 and the surface facing the heating nip) along the substrate length. Heat-resistant and insulating heater surface protective layer 1c overcoated on the surface of the heater substrate on which the energized heating resistor 1b is formed. D. Temperature detecting element 1 provided on the back side of heater substrate 1a
d, etc., and is a substantially flat plate having a low heat capacity as a whole.

The heater substrate 1a has a length of, for example, 240
This is a ceramic material substrate made of alumina (aluminum oxide, Al ₂ O ₃ ) having a thickness of 10 mm and a width of 10 mm and a thickness of 1 mm.

The heating resistor 1b is made of, for example, an electric resistance material paste (resistance paste) such as silver palladium (Ag / Pb) or Ta ₂ N, for example, with a thickness of 10 μm and a width of 1 to 3 m.
m, two heaters are formed by applying a pattern on the surface of the heater substrate in parallel along the longitudinal direction of the substrate by screen printing or the like, followed by firing.

The two parallel current-carrying heating resistors 1b, 1b
Are electrically connected to each other by a conductive path pattern 1e.

Reference numerals 1f and 1g denote a pair of first and second electrode patterns (heater electrodes) juxtaposed on one longitudinal end surface of the heater substrate surface, respectively. The end is electrically connected to the end of the other heating resistor 1b.

As described above, a series electric circuit (primary circuit, AC line) of the first electrode pattern 1f → one energized heating resistor 1b → conductive path pattern 1e → the other energized heating resistor 1b → second electrode pattern 1g ) Is configured.

1h and 1j are a pair of third and fourth electrode patterns (heater electrodes) arranged side by side on the other end face of the heater substrate surface in the longitudinal direction.

Reference numerals 1k and 1m denote conductive path patterns formed substantially in parallel on the back side of the heater substrate from the left end to the substantially central portion in the longitudinal direction of the heater substrate. The temperature detecting element 1d is a thermistor, and the thermistor 1d is electrically connected between the tips of the parallel conductive path patterns 1k and 1m to be bonded to the back surface of the heater substrate with a heat-resistant and conductive adhesive. It is arranged.

The parallel conductive path patterns 1k, 1
m, the other end of one conductive path pattern 1k is electrically connected to the third electrode pattern 1h on the heater substrate surface side via a conductive through hole 1n. The other end of the other conductive path pattern 1m is electrically connected to the fourth electrode pattern 1j on the heater substrate surface side through a conductive through hole 1p.

As described above, the third electrode pattern 1h → the conductive through hole 1n → the one conductive path pattern 1k → thermistor 1d → the other conductive path pattern 1m → the conductive through hole 1p → the fourth electrode pattern 1j. A series electric circuit (secondary circuit, DC line) is configured.

In the above, the first to fourth electrode patterns 1f, 1g, 1h, 1j, the conductive path patterns 1e, 1
The conductive portions of k, 1m, and through holes 1n, 1p are formed by pattern-coating an electric conductor material such as a silver paste by screen printing or the like, followed by baking.

In this embodiment, the heater surface protective layer 1c is a heat-resistant glass coat layer. On the front side of the heater substrate 1a, the first and second and third and fourth electrode patterns 1f,
Except for the portions 1g, 1h, 1j, the current-generating heating resistors 1b,
1b.

The above-mentioned heater 1A has a surface side (electric heating resistors 1b, 1b, electrode patterns 1f, 1g, 1h,
The heater holder 1 is provided in a heater fitting groove 2a formed along the length of the lower surface of the heater holder 2 with the outer side of the heater substrate (the surface of the heater substrate provided with 1j and the like) facing outward.

The heater connector 5 for power supply is connected to an extended overhang 2b at one end of the heater holder 2 (FIG.
FIG. 13). In addition, a heater connector 6 for temperature detection is attached to the extension projecting portion 2c on the other end side of the heater holder 2.

By assembling the heater connector 5 and the heater connector 6, the first and second spring contact portions 5a and 5b (FIGS. 12 and 13) in the power supply heater connector 5 are connected to the heater 1A.
The first and second spring contact portions 6a and 6b in the temperature measuring heater connector 6 are connected to the third and fourth electrode patterns 1h and 1j with respect to the first and second electrode patterns 1f and 1g on the side. On the other hand, they are pressed against each other and become electrically connected. At the same time, the respective spring contact portions 5a, 5b, 6a, 6
In b, a force acts in the direction of pressing the heater 1A against the heater holder 2, so that the heater 1A is held by the heater holder 2 without bonding.

Reference symbol w denotes lead wires of the heater connectors 5 and 6, which are electrically connected to the spring contact portions 5a, 5b, 6a and 6b.

Thus, power is supplied between the first and second electrode patterns 1f and 1g of the AC line of the heater 1A from a power supply circuit including the commercial power supply 12, the AC driver 13, and the like via the power supply heater connector 5. As a result, the current-carrying heating resistors 1b, 1b of the AC line generate heat, and the predetermined effective heating length region of the heater 1A quickly rises in temperature.

The heater connector 6 for temperature detection is A / C
The A / C converter 15 is in communication with the converter 15 and the thermistor voltage of the DC line is taken out from the third and fourth electrode patterns 1h and 1j via the temperature measuring heater connector 6 to the A / C converter 15 as temperature information of the heater 1A. The data is taken into the control circuit (CPU) 16 as digital data. The control circuit 16 controls the AC driver 13 to control the temperature of the heater 1A to a predetermined constant temperature based on the input digital data. That is, the power supply to the AC line is controlled to control the temperature of the heater 1A.

Reference numeral 14 denotes a safety element such as a thermal fuse or a thermoswitch, which is inserted in series into a power supply circuit for the AC line of the heater 1A and is disposed in contact with or close to the back surface of the heater 1A. When the heater 1A runs out of control for some reason and the heater is overheated to a predetermined allowable temperature or more, the heater 1A is activated to cut off the power supply circuit. Reference numeral 2d (FIGS. 11 and 12) denotes a through hole provided in a heater fitting groove 2a formed along the length of the lower surface of the heater holder 2 and the safety element 14 is fitted into the through hole 2d. It is in contact with or close to the back surface of 1A.

In recent years, the printing speed of a film heating type heating apparatus has been increasing. In such a case, it is required to raise the fixing temperature or to rapidly raise the temperature. Therefore, when the material of the heater substrate 1a is alumina as in the related art, the heater may be damaged due to thermal stress. Therefore, the thermal conductivity of aluminum nitride (Al) is about 10 times better than that of alumina.
N) has attracted attention as a heater substrate.

In this heater, since the thermal conductivity of the heater substrate is extremely good, a current-generating heating resistor is formed on the side of the heater substrate facing the surface of the heating nip as in the prior art. Rather than providing a protective layer of bad glass, a heating resistor is provided on the back side of the heater substrate opposite to the surface of the heating nip of the heater substrate, and the material surface of the heater substrate itself faces the heating nip portion Such a system has been proposed (backside heating type).

In order to use the above-mentioned heater connector also in the electrical connection in this case, similarly to the above-mentioned heater, an electrode pattern as a heater electrode is provided on the heater substrate surface side through a conductive through hole on the heater. I was

[0041]

However, in such a heating apparatus, in order to provide an electrode pattern on the front side of the heater (heater substrate), a hole called a through hole is formed on the heater substrate to reduce material strength. In some cases, the heater may be destroyed during use, and there is a problem in reliability.

Also, the conduction of the through-hole portion has a problem in reliability compared to the normal conduction of the conductive pattern portion.

In addition, when the through holes are opened, and since the patterns are formed on both the front and back surfaces of the heater substrate by printing or the like through the through holes, the number of steps is increased and the cost is increased.

Therefore, in order to eliminate through holes in the heater, a system in which an electrode pattern is present on the back surface of the heater substrate is required. However, in such a back electrode pattern heater, the contact pressure for electrical connection is set by the heater holder. Since it works in a direction away from the heater holder, there is a problem that the assembly becomes difficult when the heater is not bonded to the heater holder.

Further, even if they are adhered, since the contact pressure is always applied in a direction to separate the heater from the heater holder, there is a problem that the adhesive comes off or the contact pressure changes even if it does not come off.

Accordingly, an object of the present invention is to provide an electrically insulating substrate, a heater having a basic configuration of a current-generating resistor provided on the substrate, a heater holder for supporting the heater, and a heater on the heater side. Regarding a heating device having a heater connector for making an electrical connection with the electrode, even if the heater is a back electrode pattern heater, that is, even if there is a heater electrode on the back surface of the heater (heater holder supporting side), the heater electrode and the heater connector side A good electrical connection with the contacts can be realized in a simple and compact manner.

It is another object of the present invention to have a good assembly even when the heater is not bonded to the heater holder, so that the heater can be firmly pressed against the heater holder even after the heater is assembled.

[0048]

According to the present invention, there is provided a heating apparatus and an image forming apparatus having the following constitutions.

(1) An electrically insulative substrate, a heater having a basic configuration of a current-generating resistor provided on the substrate, a heater holder for supporting the heater, and a heater for electrically connecting to the heater In a heating device having a connector, at least one or more heater electrodes on the heater side electrically connected to the heater connector are provided on a heater surface on a side where the heater is supported by the heater holder. An intermediate contact member having conductivity at a position corresponding to the electrode is held by the heater holder or the heater, and the heater connector sandwiches the heater and the heater holder in a direction of crimping both, and the intermediate connector member is interposed therebetween. Wherein the heater connector and the heater electrode are in contact with and electrically connected to each other. Heat equipment.

(2) The heating device according to (1), wherein the heater electrode has a structure in which an electric conductor is applied on a heater surface on a side where the heater is supported by the heater holder. apparatus.

(3) The heating device according to (1) or (2), wherein the intermediate contact member has flexibility.

(4) The clamping pressure at which the heater connector clamps the heater and the heater holder is greater than the contact pressure of the intermediate contact member with the heater connector. The heating device according to any one of (1) to (3), wherein the heating device is pressed and held on the heater holder.

(5) In a heating apparatus having an electrically insulative substrate, a heater basically including a current-generating resistor provided on the substrate, and a heater holder for supporting the heater, the heater on the heater side At least one electrode
One or more heaters are provided on a heater surface on a side supported by the heater holder, and the heater has a heater connector in contact with the heater electrode from a surface side supported by the heater holder; A heating device, comprising: a pressing member that sandwiches the heater and the heater holder in a direction that opposes the contact pressure of the heater connector, and the heater electrode and the heater connector are electrically connected. .

(6) The heating device according to (5), wherein the heater electrode is configured such that an electric conductor is applied on a heater surface on a side where the heater is supported by the heater holder. apparatus.

(7) The holding pressure of the holding member in the direction in which the heater and the heater holder are brought into close contact with each other is larger than the contact pressure of the heater connector. After the holding member is assembled, the heater is pressed against the heater holder. The heating device according to (5) or (6), wherein the heating device is held.

(8) A pressurizing member for forming a heating nip portion by pressing against the heater via another member or directly is provided, and a material to be heated is introduced into the heating nip portion to be nipped and conveyed. The heating device according to any one of (1) to (7), wherein the material to be heated is heated by the heat of the heater.

(9) The heating device according to (8), wherein the other member is a film material.

(10) The heating device according to any one of (1) to (9), which is an image heating device for heating a recording material carrying an image.

(11) An image heating and fixing apparatus for heating and fixing an unfixed image on a recording material (1).
The heating device according to any one of (1) to (9).

(12) In an image forming apparatus having an image forming means for forming and carrying an unfixed image on a recording material and a fixing means for heating and fixing the unfixed image formed and carried on the recording material, the fixing means is ( An image forming apparatus, which is the heating apparatus according to any one of (1) to (9).

<Operation> a) A system having a heater connector (electrical connector) for making electrical connection by sandwiching the heating surface side of the heater and the side opposite to the heater support side of the heater holder, wherein the heater is on the heater holder support side. When a heater electrode (electrode pattern) is provided on the heater holder, an intermediate contact member that contacts the heater electrode and applies a force in a direction to separate the heater from the heater holder is held by the heater holder, and a part of this intermediate contact member and the heater connector are in contact with each other. Thus, even if there is an electrode on the back surface of the heater (the side on which the heater holder is supported), good electrical connection can be realized as a simple and compact device.

As described above, since it is possible to make contact from the heater electrode on the back surface of the heater, there is no through hole in the heater, so that a reliable heater can be realized and the cost in the manufacturing process can be reduced. .

Further, the whole structure is simple, and the space can be realized in the same space as that of the conventional electric connector having the surface electrodes.

B) At this time, by setting the clamping pressure of the heater connector to be higher than the contact pressure of the intermediate contact member, the heater connector has good assembling properties even when the heater is not bonded, and after the heater connector is assembled. Even in this state, the heater is firmly pressed against the heater holder.

In this configuration, since the heater is pressed against the heater holder when the heater connector is incorporated, it is possible to realize a system in which the heater is not bonded to the heater holder even in the case of the heater having the back electrode pattern. In addition, a good assemblage at that time can be realized.

C) When the heater has a heater electrode on the heater holder support side in a system having a heater connector for electrically connecting the heating surface side of the heater and the heater holder on the side opposite to the heater support side, the heater electrode The intermediate contact member that can obtain contact pressure in the shape of sandwiching the heater is held by the heater, and a part of this intermediate contact member and the heater connector are in contact with each other, so that there is an electrode on the back surface of the heater (heater holder support side). Also, good electrical connection can be realized as simple and compact.

Also in this case, the heater has no through-hole, and a reliable heater can be realized and the cost in the manufacturing process can be reduced.

Further, since the intermediate contact member has the same function as the electrode on the heater surface, the intermediate contact member can be assembled without the need for bonding the heater, and the space is the same as that of the conventional electrical connector for the surface electrode. realizable.

D) When the heater has a heater electrode on the heater holder supporting side, the heater is in contact with the heater electrode,
A heater connector that applies contact pressure in the direction that separates the heater from the heater holder is held in the heater holder, and is larger than the contact pressure of the heater connector in the direction that opposes the contact pressure of the heater connector and that makes the heater and the heater holder adhere closely. Providing the pressing member for applying force makes it possible to achieve good electrical connection easily and compactly even if there is an electrode on the back surface of the heater (on the side where the heater holder is supported). That is, reliable electrical connection can be achieved easily and in a small space. Also, the assemblability is good, and it is not necessary to bond the heater to the heater holder.

Further, since it is possible to make contact from the electrode pattern on the back surface of the heater, there is no through hole in the heater, and it is possible to realize a reliable heater and reduce the cost in the manufacturing process. Become.

Further, in the present invention, since there is only one contact portion, a more reliable electrical connection can be realized.

[0072]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment (FIGS. 1 to 5) FIG. 1 is a schematic cross-sectional view showing a schematic configuration of a heating device according to the present invention. FIG. 2 is an enlarged model diagram of a heating nip portion, FIG.
Is an exploded perspective model view.

The heating apparatus of this embodiment is the same as the apparatus shown in FIGS. 9 to 13 described above, and is a film heating system using a cylindrical film, a pressure roller drive system, and a tensionless type image heating system (heat fixing system). Device).

Components and parts common to those in the above-described devices of FIGS. 9 to 13 are denoted by the same reference numerals, and the description thereof will not be repeated. Hereinafter, mainly the components specific to the apparatus of the present embodiment will be described.

(A) Heater 1 The heater 1 as the heating element in this embodiment is a backside heating type / backside electrode using aluminum nitride (AlN) having a thermal conductivity about 10 times higher than that of alumina as the heater substrate 1a. It is a pattern heater.

FIG. 4A is a plan model diagram of the heater 1 with the middle part omitted on the front side, and FIG. 4B is a plan model diagram with the middle part omitted and partly cut away on the back side.

When the heater / film heating surface side of the heater substrate 1a is the substrate front side (heater front side) and the opposite side is the substrate rear side (heater rear side), the heater 1 On the back side, as shown in FIG. 3 (b), the first electrode pattern 1f → the one energized heating resistor 1
b → conductive path pattern 1e → the other energized heating resistor 1b →
A primary circuit (AC line) composed of a series electric circuit of the second electrode pattern 1g, a third electrode pattern 1h, one conductive path pattern 1k, thermistor 1d, another conductive path pattern 1m, and a fourth electrode pattern 1j. , A secondary circuit (DC line) composed of a series electric circuit (a backside heating type / backside electrode pattern heater), and a heater substrate 1
There is no through hole in a.

On the back side of the heater substrate,
First and second and third and fourth electrode patterns 1f, 1
g, 1h, and 1j, except for the portions of the heating resistors 1b, 1
b, the thermistor 1d and the conductive path patterns 1k and 1m are covered to form a heat-resistant glass coat layer 1c as a protective layer. The safety element 14 is in contact with or close to the surface of the heat-resistant glass coat layer 1c as a protective layer on the back side of the heater substrate.

The front side of the heater substrate 1a is the AlN material surface of the heater substrate 1a.
Faces the surface of the heating nip.

(B) Electrical Connection of Heater 1 The electrical connection of the above-mentioned backside heating type / backside electrode pattern heater 1 and the manner of assembly as a heater assembly will be described.

In FIGS. 3 and 5, reference numeral 7 denotes an intermediate contact member, which is a conductive member having flexibility (spring elasticity), for example, a member made of Ti-Cu. The intermediate contact member 7 has a substantially U-shaped (clip type) shape that follows the three surfaces of the extended portions 2b and 2c of the heater holder 2, and a contact portion with the electrode on the side facing the heater 1. 7a has an R-shape, and has a movable shape due to spring properties.

The heater holder 2 is provided with grooves 2e for inserting and holding the intermediate contact member 7 at positions corresponding to the electrode patterns 1f, 1g, 1h, 1j of the heater 1, respectively.

Four intermediate contact members 7 are inserted and mounted in each groove 2 e of the heater holder 2 for convenience. In the inserted and mounted state, the burrs 7b of the intermediate contact member 7 and the recesses 2f of the heater holder 2 are engaged so that the intermediate contact member 7 does not fall off. Also, the escape groove 2 of the heater holder 2
A space is secured so that the contact portion 7a of the intermediate contact member 7 is movable by g (FIGS. 5C and 5D).

In this state, a reinforcing stay 4 having an inverted U-shaped cross section is provided inside the heater holder 2, and a heater connector for power supply (hereinafter, referred to as a power connector) is provided in a cutout portion of the reinforcing stay 4. The flange (not shown) on the 5th side is fitted.

Thereafter, the heater 1 is connected to the heater holder 2
Is temporarily held in the shape of being pressed against the heater holder 2 against the spring force of the intermediate contact member 7 by the operator in the groove 2a.

[0086] the width W ₂ of the groove 2a of the heater holder 2 Yes set greater at a predetermined than the width W ₁ of the heater 1 (FIG. 5
(C)), the heater 1 has a play so as to be movable without being adhered and fixed to the heater holder 2. At this time, the contact portion 7a of each intermediate contact member 7 and the electrode pattern 1 of the heater 1
f, 1g, 1h, and 1j are pressed and electrically connected.

The power supply connector 5 has a housing portion 5d having an opening 5c fitted outside the extension portion 2b on the end side of the heater holder 2 with the upper and lower sides of the extension portion being sandwiched between the housing portion 5d and the inside thereof. The first spring contact portion 5a and the second spring contact portion 5b are made of the same material as the intermediate contact member 7, for example, Ti-Cu. First and second spring contact portions 5a and 5b in the power supply connector 5 are provided on the intermediate contact member 7 side opposite to the heater 1 side.

Then, while the operator holds the heater 1 in the heater holder 2 with one hand, the power supply connector 5 is attached to the extension protrusion 2b on one side of both ends of the heater holder 2 with the other hand. A mouth 5c extends in a direction perpendicular to the longitudinal direction of the heater 1 and from the side opposite to the rotation direction R of the pressure roller 11 in the heating nip N to the side of the extension connector 2b on the side where the heater connector is inserted. Are fitted and inserted sufficiently until the further connector insertion movement is prevented (FIG. 5 (c) → (d)).

In the state where the power supply connector 5 is fitted, the first and second spring contact portions 5a and 5b are pressed against the respective intermediate contact members 7 to be in an electrically conductive connection state (FIG. 5 (d)). )). At this time, since the pressing force of the first and second spring contact portions 5a and 5b in the power supply connector 5 is set to be larger than the pressing force of the contact portion 7a of the intermediate contact member 7, the heater 1 can be mounted even after assembly. Is pressed against the heater holder 2 (FIG. 5D).

Also, the first spring contact portion 5a in the power supply connector 5 → the intermediate contact member 7 → the first electrode pattern 1f → the one heating resistor 1b → the conductive path pattern 1e → the other heating resistor. A series of electric paths (AC lines) are constituted by the resistor 1b → the second electrode pattern 1g → the intermediate contact member 7 → the second spring contact portion 5b in the power supply connector 5.

Next, in this state, the film 3 is loosely fitted outside the heater holder 2, the heater 1, and the reinforcing stay 4, and a heater connector for temperature measurement (hereinafter referred to as power supply) is inserted into one of the cutouts of the reinforcing stay 4. A flange (not shown) on the 6 side is fitted.

Since the structure of the temperature detecting connector 6 is the same as that of the power feeding connector 5, the description of the structure is omitted.

In the above state, the operator again causes the heater 1 to move the heater holder 2 against the spring force of the intermediate contact member 7.
In the state where the heater is pressed, the temperature measuring connector 6 is heated in the direction perpendicular to the longitudinal direction of the heater 1 with respect to the extension protrusions 2c on the other side of both ends of the heater holder 2 as in the case of the power supply connector 5. The mouth 6c abuts on the side of the extension projecting portion 2c on the side of the heater connector fitting insertion side from the side opposite to the rotation direction of the pressure roller 11 in the nip portion N, and is received to prevent further connector fitting insertion movement. Until it is fully inserted and assembled.

With the temperature detecting connector 6 fitted, the first and second spring contact portions 6a and 6b are pressed against the respective intermediate contact members 7 to be electrically connected. At this time, similarly to the case of the power supply connector 5, the pressing force of the first and second spring contact portions 6a and 6b in the temperature detecting connector 6 is set to be larger than the pressing force of the spring contact portion 7a of each intermediate contact member 7. After the assembly, the heater 1 remains in the heater holder 2
It is in a state pressed against.

Further, the first spring contact portion 6a in the temperature detecting connector 6 → the intermediate contact member 7 → the third electrode pattern 1h → the conductive path pattern 1k → thermistor 1d → the conductive path pattern 1m → the fourth electrode A series of electric paths (DC lines) are constituted by the pattern 1j → the intermediate contact member 7 → the second spring contact portion 6b in the connector 6 for temperature detection.

Thus, the assembly as the heater assembly is completed.

During operation as an actual image heating / fixing apparatus, the heater connector 5 for power supply is provided between the first and second electrode patterns 1f and 1g of the AC line of the heater 1 via the intermediate contact member 7, respectively. From the AC power supply 12 by the first and second spring contact portions 5a and 5b.
3. When power is supplied through the lead wire w, the current-carrying heating resistors 1b, 1b of the heater 1 generate heat over the entire length, and the temperature of the heater 1 rapidly rises.

Further, the temperature rise of the heater 1 is detected by the thermistor 1d, and the temperature measurement information is transmitted to the third and fourth electrode patterns 1h and 1j of the DC line, the intermediate contact member 7,
First and second spring contact portions 6a, 6 of connector 6 for temperature detection
b, a lead wire w, and a control unit (C
PU) 16. The A / D converter 15 digitizes the output of the thermistor 1d and inputs it to the control unit 16.

The control unit 16 controls the AC triver 13 including the triac based on the input heater temperature information so that the surface temperature of the heater 1 is maintained at a predetermined heating temperature (fixing temperature). To control the heater 1 by controlling the power supplied to the current-carrying heating resistors 1b, 1b.

In the state where the temperature of the heater 1 is controlled to a predetermined fixing temperature, the material to be heated having an unfixed toner image t between the pressure roller 11 of the fixing nip N and the fixing film 3 is used. When the recording material P is nipped and conveyed, the heat of the heater 1 is applied to the recording material via the fixing film 3, and the toner image t is heated and fixed on the recording material P.

As described above, with the intermediate contact member 7 interposed, the electrode patterns 1f, 1g, 1 on the back side of the heater 1, that is, on the side opposite to the heating nip surface.
Even if there is h, 1j, it is possible to electrically connect the heater connectors 5 and 6 of the conventional method.

Further, the configuration is simple and the space can be realized in the same space as the conventional heater connector.

In addition, since the conventional heater connector system can be used, the heater connector can be diverted in some cases, so that the cost can be reduced.

Further, by doing so, the electrode patterns 1f, 1g, 1h, and 1j are provided on the back side of the heater 1 so that the contact pressure is applied in the direction in which the heater 1 is peeled off from the heater holder 2. Also, it is possible to incorporate the heater 1 into the heater holder 2 without bonding the heater 1 to the heater holder 2, and to improve the assemblability.

Further, in the present embodiment, aluminum nitride having good heat conductivity is used for the heater substrate (base material) 1a.
Since a heater without through holes can be realized by making contact from the back side, a heater excellent in both thermal stress and material strength can be obtained. And a heat-fixing device having a high temperature can be realized.

In the present embodiment, the case where the heater is provided with the heating element (electric heating resistor) 1b and the temperature detecting element 1d on the back side has been described, but the present invention is not limited to this. At least one of the heaters may be a heater on which a back-side electrode pattern is provided. For example, a heater in which electrode patterns are provided on both sides, or a temperature detecting element 1d is a separate body, The effect of the present invention does not change even if the heater has the heating element 1b disposed only on the back surface.

<Second Embodiment> (FIG. 6) FIG. 6 is a schematic sectional view showing the vicinity of a heater connector according to this embodiment.

This embodiment differs from the first embodiment only in the configuration near the heater connector.

Here, the intermediate contact member 7 is made of a flexible and conductive material, has a substantially U-shape, and has a portion 7a in contact with the back electrode patterns 1f, 1g, 1h, 1j of the heater 1. Has an R shape, and has a shape such that a predetermined contact pressure can be obtained by sandwiching the plate thickness portion of the heater 1.

Back electrode patterns 1f, 1 of heater 1
g, 1h, and 1j, the intermediate contact member 7 is inserted and clamped at each of the locations, and the electrode patterns 1f, 1g, 1h, and 1
j and the intermediate contact member 7 are in an electrically connected state ((a) → (b) in FIG. 6). In this state, the heater 1 is in a state equivalent to an electrode pattern on the front side due to the intermediate contact member 7. The heater 1 to which the intermediate contact member 7 is attached is fitted into the groove 2a of the heater holder 2, and the power supply heater connector 5 and the temperature measurement heater connector 6 are assembled (FIG. 6C).

Thus, through each intermediate contact member 7,
The first and second spring contact portions 5a and 5b in the power supply heater connector 5 correspond to the first and second electrode patterns 1 of the heater 1.
The first and second spring contact portions 6a and 6b in the heater connector 6 for temperature detection are pressed against the third and fourth electrode patterns 1h and 1j of the heater 1, respectively, for f and 1g. To a conductive connection state.

As described above, the electrode patterns 1f, 1g, 1
Even if there are h and 1j, reliable and simple electrical connection can be achieved in a small space. In addition, the assemblability is exactly the same as the conventional case where there is an electrode pattern on the front surface side of the heater, and it is not necessary to bond the heater 1 to the heater holder 2 in the same manner. Also, since it is possible to make contact from the electrode patterns 1f, 1g, 1h, 1j on the back surface of the heater, the heater has no through-holes, realizing a reliable heater and reducing costs in the manufacturing process. It becomes possible.

<Third Embodiment> (FIG. 7) FIG. 7 is a schematic sectional view of the vicinity of the heater electrode portion of the present embodiment. This embodiment is different from the first embodiment only in the configuration near the heater electrode portion.

Here, the intermediate contact member 7 and the lead wire w described in the first embodiment are integrated into a contact lead wire 8 serving as an electrical connector.

The contact lead wires 8 are attached to the respective grooves 2e of the heater holder 2 (FIG. 7 (a)).
→ (b)).

Electrode patterns 1f, 1g, 1 of heater 1
h, 1j, the contact portion 7a of the contact lead wire 8 is R
It has a shape and is movable due to its spring properties. A holding member 9 for holding the heater 1 and the heater holder 2 in close contact with each other including the contact lead wire 8 is provided. A holding spring 9 for pressing the heater 1 against the support surface of the heater holder 2 is provided inside the holding member 9.
a is provided.

At this time, the spring pressure of the presser spring 9a is set higher than the contact pressure of the contact lead wire 8.

The heater 1 is provided with a groove 2a of the heater holder 2 so as to resist the contact pressure of the contact lead wire 8 by an operator.
The pressing member 9 is inserted and fitted and held in this state ((c) state in FIG. 7).

In the assembled state, since the pressure of the presser spring 9a is set to be higher than the contact pressure of the contact lead wire 8, the heater 1 is pressed against the heater holder 2 and the contact lead wire is pressed. 8, a predetermined contact pressure is obtained, and the electrode patterns 1f, 1
g, 1h, 1j and the contact lead wire 8 are electrically connected.

Also in this embodiment, the contact lead wire 8 is interposed and the heater 1 is pressed against the heater holder 2 by the separate pressing member 9, so that the electrode pattern 1f is formed on the heater holder support side (heater back surface). , 1g, 1
Even if there are h and 1j, reliable and simple electrical connection can be achieved in a small space.

Further, since it is possible to make contact from the electrode pattern on the back surface of the heater, there is no through hole in the heater, and it is possible to realize a reliable heater and reduce the cost in the manufacturing process. Become.

Further, in the case of the present embodiment, the outer shape of the holding member 9 is changed to the heater connector 5 in the first or second embodiment.
6 is a double structure having a shape similar to the housings 5d and 6d and having a holding spring 9a inside. However, any shape may be used as long as the structure is such that the heater 1 is pressed against the heater holder 2; A configuration in which the heater is pressed by its spring property alone may be used.

<Fourth Embodiment> (FIG. 8) FIG. 8 is a schematic configuration diagram of an example of an image forming apparatus. The image forming apparatus of this embodiment is a laser beam printer using a transfer type electrophotographic process.

Reference numeral 51 denotes an apparatus housing, and 52, an electrophotographic photosensitive drum as an image carrier, which is driven to rotate at a predetermined peripheral speed (process speed) in a clockwise direction indicated by an arrow.

The photosensitive drum 52 is primary-charged uniformly to a predetermined polarity and potential by a charging roller 53 during the rotation process, and a charged image is output from a laser scanning exposure device (laser scanner) 54 to a target image. Scanning exposure is performed by laser light L modulated according to a time-series electric digital pixel signal of information, and an electrostatic latent image corresponding to target image information is formed on the peripheral surface of the drum.

The latent image is developed as a toner image by the developing device 55, and the toner image reaches a transfer nip n between the photosensitive drum 52 and the transfer roller 56.

On the other hand, the recording material (transfer material) P in the paper feed cassette 58 is conveyed one by one by the paper feed roller 57, introduced into the transfer nip n at a predetermined timing through the sheet path 59, and transferred. An electric field having a polarity opposite to that of the toner is applied to the photosensitive drum 52 from the rear surface of the recording material P by the roller 56.
Is transferred onto the surface of the recording material P.

After receiving the transfer of the toner image, the transfer nip n
Is separated from the surface of the photosensitive drum 52 and guided to the conveyance guide 60 to enter the heat fixing device 100. This heat-fixing apparatus is, for example, the first type according to the present invention.
The recording material P passes through the fixing nip portion N of the apparatus 100, receives the toner image by heating and fixing as described above, and causes the sheet path 62 to move through the sheet path 62. It is discharged to the outside of the device.

After the transfer of the toner image to the recording material P, the surface of the photosensitive drum 52 is cleaned by the cleaning device 63 and repeatedly used for image formation.

<Others> 1) In the heater 1, the heater substrate 1a is not limited to aluminum nitride. For example, other ceramic materials such as silicon carbide (SiC) and aluminum oxide can be used.

The pattern form of the current-generating heating resistor, electrodes, etc. formed on the heater is also arbitrary. The arrangement of the temperature detecting means is also optional.

2) A desired functional layer may be formed on the front side of the heater 1 if necessary. An appropriate amount of a lubricant such as heat-resistant grease can be interposed between the surface side of the heater 1 and the film 3.

3) The pressing member 11 is not limited to the roller body, but may be a rotating body such as a rotating belt body.

4) In the case of a film heating type heating device, an endless belt-like or cylindrical film is used as a driving method of the film 3, and a driving roller is disposed on the inner peripheral side of the outer film. A drive system in which a film is stretched by applying tension between a plurality of members including a drive roller and driven to rotate by a drive roller may be used. It has the advantage that film transportability can be increased. The tensionless drive system as in the embodiment has an advantage that the configuration can be simplified and a low-cost heating device can be realized.

It is also possible to use an apparatus in which a rolled long film having a web shape is used and the film is run while being rewound from the pay-out side to the take-up side.

5) In the present invention, the heating device is not limited to the heat fixing device of the embodiment, but may be an image heating device that heats a recording material carrying an image to improve the surface properties such as gloss. Apparatuses for widely heating a material to be heated, such as an image heating device, a device for heating and drying a material to be heated, and a heating laminating device are included. Further, the film heating method need not be used.

6) In the image forming apparatus, the principle and process of forming an image on the recording material P are arbitrary.

[0138]

As described above, according to the present invention, there are provided an electrically insulating substrate, a heater having a basic structure of an electric heating resistor provided on the substrate, and a heater holder for supporting the heater. Regarding a heating device having a heater connector for making electrical connection with the heater electrode on the heater side, even if the heater is a back electrode pattern heater,
That is, even if there is a heater electrode on the back surface of the heater (on the heater holder support side), good electrical connection between the heater electrode and the contact on the heater connector side can be realized as a simple and compact device.

Even when the heater is not bonded to the heater holder, the heater has a good assembly name, and the heater is firmly pressed against the heater holder even after the heater is assembled.

Since it is possible to make a contact from the electrode pattern on the back surface of the heater, there is no through hole in the heater, so that a reliable heater can be realized and the cost in the manufacturing process can be reduced.

Further, the whole structure is simple, and the space can be realized in the same space as that of the conventional electric connector having the surface electrodes.

Even in the case of the heater having the back electrode pattern, it is possible to realize a system in which the heater is not bonded to the heater holder. In addition, a good assemblage at that time can be realized.

In the present invention, since there is only one contact portion, a more reliable electrical connection can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a heat fixing device according to a first embodiment.

FIG. 2 is an enlarged model diagram of a heating nip portion.

FIG. 3 is an exploded perspective view of the apparatus.

FIG. 4 is a configuration diagram of a heater.

FIG. 5 is a view for explaining the electrical connection of the heater and how the heater assembly is assembled.

FIG. 6 is a view for explaining the electrical connection of a heater and the manner of assembly as a heater assembly in a second embodiment.

FIG. 7 is a view for explaining the electrical connection of the heater and the manner of assembly as a heater assembly in the third embodiment.

FIG. 8 is a schematic configuration diagram of an image forming apparatus according to a fourth embodiment.

FIG. 9 is a schematic cross-sectional view of a conventional heat fixing device.

FIG. 10 is an enlarged model diagram of a heating nip portion.

FIG. 11 is an exploded perspective view of the apparatus.

FIG. 12 is a configuration diagram of a heater.

FIG. 13 is a view for explaining the electrical connection of the heater and the state of assembly as a heater assembly.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Heater (heating body) 1a Heater board 1b Electric heating resistor 1f, 1g Heater electrode (electrode pattern) of AC line 1h, 1j Heater electrode (electrode pattern) of DC line 2 Heater holder 2a Heater fitting groove 2b, 2c Heater Extension projecting part of holder 2e Intermediate contact member fitting groove 5 Power supply heater connector 5a, 5b Spring contact part 6 Heat detection heater connector 6a, 6b Spring contact part 7 Intermediate contact member 8 Contact lead wire 9 Holding member

Continued on the front page F term (reference) 2H033 BA26 BE03 3K058 AA02 AA41 BA18 CA23 CA61 CE04 CE13 CE19 DA04 GA06 3K092 PP18 QA05 QB32 QC02 QC07 QC25 QC43 QC49 RF03 RF11 RF17 RF22 TT07 TT22 UA06 VUAV40V16V16V16V16V16V16V16V

Claims (12)

[Claims] An electric insulating substrate, a heater having an electric heating resistor provided on the substrate as a basic structure, a heater holder for supporting the heater, and a heater connector for making an electrical connection with the heater. In the heating device having at least one heater electrode on the heater side electrically connected to the heater connector, the heater electrode is provided on a heater surface on a side where the heater is supported by the heater holder. An intermediate contact member having conductivity at a position corresponding to is held by the heater holder or the heater, and the heater connector sandwiches the heater and the heater holder in a direction of crimping the two, and via the intermediate contact member The heating is characterized in that the heater connector and the heater electrode are in contact with and electrically connected to each other. Location. 2. The heating device according to claim 1, wherein the heater electrode has a structure in which an electric conductor is applied on a heater surface on a side where the heater is supported by the heater holder. . 3. The heating device according to claim 1, wherein the intermediate contact member has flexibility. 4. The heater connector according to claim 1, wherein said clamping pressure in which said heater connector clamps said heater and said heater holder is greater than a contact pressure of said intermediate contact member with said heater connector. The heating device according to any one of claims 1 to 3, wherein the heating device is pressed against and held by a heater holder. 5. A heating apparatus comprising: an electrically insulating substrate, a heater having a current-generating resistor provided on the substrate, and a heater holder for supporting the heater, wherein a heater electrode on the heater side is provided. At least one or more is provided on a heater surface on a side where the heater is supported by the heater holder, and has a heater connector that contacts the heater electrode from a surface side on which the heater is supported by the heater holder. And a pressing member for holding the heater and the heater holder in a direction in which the heater and the heater holder are brought into close contact with each other in a direction against a contact pressure of the heater connector, wherein the heater electrode and the heater connector are electrically connected. Heating equipment. 6. The heating apparatus according to claim 5, wherein the heater electrode is configured such that an electric conductor is applied on a heater surface on a side where the heater is supported by the heater holder. . 7. The holding member presses and holds the heater against the heater holder after the holding member is assembled, wherein the holding pressure in which the holding member holds the heater in close contact with the heater holder is larger than the contact pressure of the heater connector. The heating device according to claim 5, wherein the heating is performed. 8. A heating member having a pressure member which forms a heating nip portion by being in pressure contact with said heater via another member or directly, wherein a material to be heated is introduced into said heating nip portion and nipped and conveyed. The heating device according to any one of claims 1 to 7, wherein the material to be heated is heated by heat of the heater. 9. The heating device according to claim 8, wherein said another member is a film material. 10. The heating device according to claim 1, wherein the heating device is an image heating device for heating a recording material carrying an image. 11. The heating device according to claim 1, wherein the heating device is an image heating fixing device that heats and fixes an unfixed image on a recording material. 12. An image forming apparatus comprising: an image forming means for forming and carrying an unfixed image on a recording material; and a fixing means for heating and fixing the unfixed image formed and carried on the recording material.
An image forming apparatus, wherein the fixing unit is the heating device according to claim 1.