JP2003282229A - Heater, fixing device, image forming device and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heater realizing enhancement of safety and temperature control with sufficient power efficiency; a fixing device applied with this heater; an image forming device mounted with this fixing device; and a recording medium storing a program to feed power to the heating source. <P>SOLUTION: The heater is provided with a temperature measurement means for measuring the temperature of the heating source; a power feed means for feeding the power to the heating source; and a temperature control means for controlling the power feed means based on a measurement value of the temperature measurement means to control the temperature of the heating source. The temperature control means provides an upper limit for the power feed to the heating source at a predetermined condition. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device having a heating source whose temperature is controlled, a fixing device in which the heating source of the heating device is used as a heating source for heating and fixing a toner image on a recording material, and the fixing device. And an image forming apparatus for heating and fixing a toner image formed on a recording material by using an electrophotographic process or the like, and a recording medium storing a program for supplying power to a heating source of the heating device. is there.

[0002]

2. Description of the Related Art In an image forming apparatus, a transfer paper, a recording paper, a photosensitive paper, an electrophotographic process, an electrostatic recording process, a magnetic recording process, various other known image forming principles, and an image forming unit according to the process. A toner image is formed on a recording material such as electrostatic recording paper by an indirect (transfer) method or a direct method, and this toner image is fixed on the recording material by a heat roller type fixing device (fixing device) to obtain a permanent image. There is.

This heat roller system uses a fixing roller (heating body) having a heater (heating source) inside and a pressure roller which is brought into pressure contact with the fixing roller, and a fixing nip portion is formed between the pair of rollers. By introducing and passing the recording material, the unfixed toner image formed and carried on the recording material surface is fixed on the recording material surface by heat and pressure.

In recent years, due to the convenience and the energy consumption reduction, there has been a demand for a thermal fixing device which has a fast start-up and does not require standby temperature control. In order to realize this, there is a method in which a heat roller having a small thickness is used to reduce the heat capacity to shorten the temperature rising time to a desired temperature. As a heat source (heating source) suitable for realizing this method, IH (electromagnetic induction heating method) can be mentioned.

This electromagnetic induction heating system has a mechanism in which a high frequency current is passed through an induction coil and the generated magnetic field is applied to a metallic roller or the like to heat the roller. The temperature is finely controlled by arbitrarily setting the power applied to the induction coil, and it is suitable as a heating means for a thin roller.

In the temperature control method, a conventional halogen lamp was used as a heat source.
Instead of the N / OFF control method, a feedback method has been considered in which the temperature of the fixing device is measured by the temperature detecting means and the electric power applied to the heat source is linearly adjusted according to the result.

FIG. 6 is a graph showing the applied power value with respect to the fixing roller temperature, where the vertical axis is the power value P applied to the heat source.
and the horizontal axis represents the temperature T. FIG. 7 shows that when the temperature of the fixing device is Ta, electric power of Pa is applied to the heat source. Considering the power value required for fixing, the power value applied to the induction coil is 0 W from the lower limit value and 1 is the upper limit value.
The range is about 500W. The efficiency of the high frequency power source considering this usage range is as shown in FIG. As is clear from FIG. 7, the power efficiency deteriorates sharply in the range of 100 W or less and 1500 W or more, and the lower limit value of the power applied to the induction coil is preferably about 100 W.

[0008]

When the conventional image forming apparatus is in the standby state, the fixing device keeps the fixing roller in a state in which the fixing roller is rotated or stopped to keep the temperature at the time of printing or a lower temperature. Be done. The power value required at this time is lower than that during printing.

However, if the range of the electric power value applied to the fixing roller is the same as that at the time of printing, when the temperature of the fixing roller suddenly fluctuates for some reason or the temperature detecting means malfunctions, the applied electric power value is changed. There is a possibility that the temperature fluctuates abruptly, the fixing roller is rapidly heated, and deformation due to local thermal expansion or seizure with the opposing pressure roller occurs.

The present invention has been made in order to solve the above-mentioned conventional problems, and in the temperature control of the feedback system, when the image forming apparatus is in the standby state, the upper limit value of the electric power value applied to the fixing device is printed. Set lower than the time, or set the applied power value to the lower limit and turn it ON /
A heating device capable of improving safety and temperature control with high power efficiency by controlling OFF, a fixing device to which the heating device is applied, an image forming apparatus equipped with the fixing device, and power supply to the heating source. It is an object of the present invention to provide a storage medium that stores a program that executes.

[0011]

The present invention provides a heating device, a fixing device, an image forming device and a recording medium having the following constitution.

(1) A temperature measuring means for measuring the temperature of a heating source, an electric power supplying means for supplying electric power to the heating source, and a control means for controlling the electric power supplying means on the basis of a measured value of the temperature measuring means. And a temperature control unit for controlling the temperature of the heating source, wherein the temperature control unit sets an upper limit value for power supply to the heating source under a predetermined condition.

(2) The heating device according to (1), wherein the predetermined condition is a standby time.

(3) The heating device according to (1), wherein the heating body having a heating source is in the shape of a roller that rotates.

(4) The heating device according to (3), characterized in that the heating element is stopped or rotated at a low speed under a predetermined condition.

(5) Temperature measuring means for measuring the temperature of the heating source, electric power supplying means for supplying electric power to the heating source, and controlling the electric power supplying means based on the measured value of the temperature measuring means. A temperature control means for controlling the temperature of the heating source, wherein the temperature control means controls ON / OFF of power supply to the heating source under a predetermined condition.

(6) The heating device according to (5), wherein the predetermined condition is a standby time.

(7) The heating device according to (5), wherein the heating body having a heating source is in the shape of a rotating roller.

(8) The heating device according to (7), characterized in that the heating element is stopped or rotated at a low speed under a predetermined condition.

(9) The recording material on which the toner image is formed is conveyed and passed through the pressure contact portion between the heating body and the pressure body, and heat and pressure are applied at the time of the passage to heat and fix the toner image on the recording material. In the fixing device, a heating device of the heating device according to any one of (1) to (8) is applied as the heating member.

(10) A toner image forming means for forming a toner image on a recording material and a fixing device for heating and fixing the toner image formed on the recording material by the toner image forming means on the recording material. An image forming apparatus characterized by applying the fixing device described in (9) as the fixing device.

(11) A storage medium, which stores a program, which is read and used by a control means for controlling power supply to a heating source and which has an upper limit value for power supply to a heating source under a predetermined condition.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) (1) Fixing Device A FIG. 1 is a schematic cross-sectional view of a main part in which the heating device of the present invention is applied as the fixing device A. Reference numeral 1 is a fixing roller (heating roller) as a heating member, and 2 is a pressure roller as a pressure member.

The fixing roller 1 is made of a conductive material that generates heat due to an induced current, and this embodiment has an outer diameter of 40 mm.
A core metal cylinder (conductive cylindrical roller) made of iron having a thickness of 0.7 mm is used as the base body 1a, and a surface release layer 1b of 10 to 50 μm of PTFE or PFA is provided to enhance the surface release property. Good. Further, in order to improve the fixing property and reduce the temperature unevenness of the roller surface, for example, a silicone rubber layer of 20 to 20 is provided between the iron cored bar cylinder and the surface release layer.
An elastic layer of 500 μm may be provided.

The pressure roller 2 is composed of a hollow core metal 11 and a surface-releasing heat-resistant rubber layer formed on the outer peripheral surface thereof, or an elastic layer 1 which is a sponge layer which also serves as heat insulation between the hollow core metal 11 and the surface.
It consists of 2.

The fixing roller 1 and the pressure roller 2 are parallel to each other with the fixing roller 1 on the upper side and the pressure roller 2 on the lower side, and both ends are provided with bearing portions between fixing unit frames (not shown). It is rotatably attached via.

The pressure roller 2 is pushed and urged by a pressure mechanism (not shown) using a spring or the like in the direction of the rotation axis of the fixing roller 1 and brought into pressure contact with the lower surface of the fixing roller 1 with a predetermined pressure to fix it. A nip portion (pressure contact nip portion) N is formed. In this example, the pressure roller 2 is loaded with a weight of about 30 kg, and in this case, the width of the fixing nip portion N (nip width) is about 6 mm. However, the nip width may be changed by changing the load depending on circumstances.

In this embodiment, the fixing roller 1 is rotationally driven by a driving mechanism (not shown), and the pressure roller 2 is driven to rotate by the frictional force in the fixing nip portion N as the fixing roller 1 is rotationally driven. To do.

Reference numeral 14 denotes an induction coil assembly which is inserted and disposed in the internal space of the fixing roller 1, and includes an induction coil 3, a coil holder 5, a core (magnetic core) 7, a stay 6 and the like.

The coil holder 5 is a trough-shaped member made of a heat-resistant resin such as PPS / PEEK / phenolic resin having a substantially semi-circular cross section. The induction coil 3 is provided by winding a wire around the coil holder 5. The core 7 is provided inside the coil holder 5 in a T-shaped cross section. And
It is integrated as the induction coil assembly 14.

The induction coil assembly 14 is inserted into the inner space of the fixing roller 1 so that the induction coil 3 on the outside of the coil holder 5 faces downward and is brought close to the inner surface of the fixing roller 1, and both ends of the stay 6 are fixed. The induction coil assembly 14 is arranged in the internal space of the fixing roller 1 by fixing and supporting the portions between fixing unit frames (not shown).

Reference numeral 4 is a temperature sensor such as a contact type thermistor or an infrared type non-contact thermistor arranged so as to come into contact with the surface of the fixing roller 1. Denoted at 10 is a separation claw, which is arranged at the recording material outlet of the fixing nip portion N in contact with or close to the surface of the fixing roller 1.

Thus, in a state in which the fixing roller 1 is rotationally driven and the pressure roller 2 is driven to rotate, a high frequency alternating current is applied to the induction coil 3 from a power supply section 51 described later. The power supply unit 51 is 10 KHz to 100 KHz
The high frequency power can be generated by a switching power supply (not shown). The induction coil 3 generates alternating magnetic flux by the high frequency alternating current supplied from the power supply unit 51. The magnetic field induced by an alternating current is
An eddy current is passed through the inner surface of the fixing roller 1 which is a conductive layer to generate Joule heat, and the fixing roller 1 is efficiently and quickly heated and heated by the Joule heat.

The temperature of the fixing roller 1 is detected by the temperature sensor 4, and the detected temperature signal is input / output port 5 described later.
It inputs to CPU56 via 7. The CPU 56 controls the power supply from the power supply unit 51 to the induction coil 3 based on the detected temperature signal input thereto to control the surface temperature of the fixing roller 1 at a predetermined constant temperature (predetermined fixing temperature). To automatically control.

In a state where the surface temperature of the fixing roller 1 is automatically controlled to a predetermined constant temperature, the recording material 13 is fed into the fixing nip portion N and is nipped and conveyed. The unfixed toner image 9 is heated and fixed on the surface of the recording material 13 under the pressure of.

In order to increase the heat generation of the fixing roller 1, the number of windings of the induction coil 3 is increased, the core 7 is made of ferrite or permalloy having a high magnetic permeability and a low residual magnetic flux density, and the frequency of the alternating current is changed. It should be high.

The induction coil 3 used in this example has 50 to 50
It is formed by winding a litz wire made of 150 twists for 6 turns. The number of turns can be, for example, 4 to 10 turns.

(2) Image Forming Apparatus FIG. 2 is a schematic configuration diagram of an image forming apparatus according to the present invention to which the fixing device A shown in FIG. 1 is applied. The image forming apparatus of this example is a laser printer 47 using a transfer type electrophotographic process and an induction heating type fixing device. Reference numeral 31 denotes a rotary drum type electrophotographic photosensitive member (hereinafter referred to as a photosensitive drum) as an image bearing member, which is rotationally driven at a predetermined peripheral speed (process speed) in a clockwise direction indicated by an arrow. The surface of the photosensitive drum 31 is uniformly charged to a predetermined polarity and potential by a charging roller 32 as a charging device during its rotation process.

Next, the laser scanner 33 as the image information writing means receives the laser beam scanning exposure L corresponding to the desired image information pattern. As a result, a laser beam electrostatic latent image corresponding to the desired image information pattern is formed on the surface of the photosensitive drum 31.

The laser beam electrostatic latent image formed on the surface of the photosensitive drum 31 is developed as a toner image by the developing device 34. As a developing method, a jumping developing method, a two-component developing method, or the like is used, and often a combination of image exposure and reversal developing is used.

The toner image formed on the surface of the photosensitive drum 31 is fed from the paper feeding section 37 to the transfer nip section 36 at a predetermined timing in the transfer nip 36 formed by the photosensitive drum 31 and the transfer roller 35. Electrostatic transfer is sequentially performed on the recorded recording material (transfer material) 13.

In the image forming apparatus of this example, the paper feeding section 37
Is a cassette sheet feeding unit, and the recording material 13 stacked and accommodated in the sheet feeding cassette is separated and fed by a sheet feeding roller 38 and a sheet separating member (not shown), and a pair of conveying rollers 39 and a top sensor ( The sheet is fed to the transfer nip portion 36 at a predetermined control timing through a sheet path 41 including a registration sensor) 40 and the like.

The leading edge of the recording material 13 fed from the cassette paper feeding section 37 to the transfer nip section 36 through the sheet path 41 is recognized by the top sensor 40 provided in the middle of the sheet path 41, and in synchronization with this. As a result, an image is formed on the surface of the photosensitive drum 31.

The recording material 13 having the toner image transferred from the surface of the photosensitive drum 31 at the transfer nip portion 36 is sequentially separated from the surface of the photosensitive drum 31 and introduced into the fixing device A through the conveyance guide 8. Then, the fixing device heats and fixes the unfixed toner image.

The recording material 13 from which the toner image has been heated and fixed, which has come out of the fixing device A, is discharged to the discharge tray section 46 by the discharge roller pair 45 through the sheet discharge path 43 including the transport roller pair 44.

On the other hand, adhering contaminants such as transfer residual toner and paper dust remaining on the surface of the photosensitive drum 31 after the toner image is transferred to the recording material 13 are removed by the cleaner 42 on the surface of the photosensitive drum 31, and the surface is cleaned. The photosensitive drum 31 is repeatedly used for image formation.

FIG. 3 is a block diagram of a basic configuration showing an electric control system of the image forming apparatus shown in FIG. 2, and the illustrated example is configured as a laser printer 47. A CPU 59 that performs basic control of the laser printer 47 is connected to a ROM 59 in which a control program is written, a work RAM 58 for performing processing, and an input / output port 57 via an address bus and a data bus. Various loads (not shown) such as a motor and a clutch for controlling the laser printer 47, a temperature sensor 4 for detecting the temperature of the fixing roller 1, and the like are connected to the input / output port 57.

The CPU 56 sequentially controls the input / output through the input / output port 57 according to the contents of the ROM 59, and executes the printing operation. Further, the CPU 56 includes an image processing unit 53 and an image memory unit 5 for storing processed images.
4. A power supply unit 51 that applies a high-frequency current is connected to the induction coil unit 3 that induction-heats the fixing roller unit 1.
The power value setting signal 60 is sent from the CPU 56 to the power supply unit 51.
Then, the power supply ON / OFF signal 61 of the AC power supply 50 is input.

In the image memory section 54, the recording material 13
An image forming section 55 for forming an unfixed toner image and an external I / F processing section 52 are connected to each other. External I / F section 5
2 develops a PDL (page description language) input from an external computer into a bitmap.

(3) Temperature Control The temperature control operation of the fixing device A when the laser printer 47 is operating will be described below with reference to the flowchart of FIG. This laser printer 47 prints,
It has three modes, standby and warm-up, and is always in one of these modes. Further, the range in which the power applied to the coil 3 can be set is from Pmin (= 100 W) to Pmax (= 150) in consideration of power efficiency (FIG. 7).
Up to 0 W), and an upper limit value Pmax of electric power that is different depending on each mode is set. The lower limit value is Pmin.

First, the mode change is determined (S01).
If the mode has not changed (NO in S01), the process proceeds to step S05. If the mode has changed (S01
Branch YES), it is determined whether the standby mode (S0
2). In the standby mode (YES at S02 branch),
The rotation of the fixing roller 1 is stopped (S03). Then, the upper limit value Pmax of the electric power applied to the coil 3 is set to the upper limit value Ps (= 200 W) in the standby mode (S04).

On the other hand, if it is determined in step S02 that the mode is not the standby mode (NO in step S02), then it is determined whether the mode is the print mode (S12). If it is the print mode (YES at S12 branch), the rotation of the fixing roller 1 is started (S13). Then, Pmax is set to the upper limit value Pp (1100 W) of the print mode (S14). If it is not the print mode (NO at S12), the fixing roller 1 is started to rotate (S1).
5). Then, Pmax is set to the upper limit value Pw (1400 W) of the warm-up mode (S16).

After the setting of the electric power upper limit Pmax in each mode is completed, the temperature of the fixing roller is then measured (S
05). According to the result measured by the temperature sensor unit 4, the coil 3
The electric power value Po applied to is calculated (S06). Next, the calculated power value Po and the power upper limit value Pma determined by the mode
x is compared, and if Po> Pmax (S07 branch YE
S) and Pmax are applied to the coil 3 (S08). Also,
If Po> Pmax (S07 branch NO), then Po
And Pmin are compared (S09), and if Po <Pmin,
(S09 branch YES), Pmin is applied to coil 3
(S11). If Po <Pmin is not satisfied (NO in S09), Po is applied to the coil (S10). Then, the process returns to step S01 again, and the loop operation is performed at predetermined time intervals according to the time measured by the timer or the like.

(Second Embodiment) Next, with reference to the flowchart of FIG. 5, a characteristic of the second embodiment of the present invention in the temperature control of the fixing device A when the laser printer 47 is operating. The part will be described. This laser printer 47 has three modes of printing, standby, and warm-up, as in the first embodiment, and is always in one of these modes. Similarly, the power that can be applied to the coil 3 is in the range of Pmin to Pmax.

The difference from the first embodiment lies in the temperature control method in the standby mode.

First, it is determined whether the mode is standby.
(S101). In standby mode (S101 branch YE
S), the rotation of the fixing roller 1 is stopped (S102). Next, the temperature of the fixing roller 1 is measured by the temperature sensor unit 4 (S
103). Subsequently, the target temperature during standby and the measured temperature are compared (S104). If the target temperature is not the measured temperature (NO in S104), apply Pmin to the coil
(S105). If target temperature> measured temperature (S104
If YES, the power application to the coil is stopped (S10).
6).

Next, it is judged whether or not the mode has changed (S
107), if the mode has not changed (S107 branch N
O), and returns to step S103. If the mode has changed (YES in step S107), the process returns to step S101.

If the mode is not the standby mode in step S101 (NO in step S101), it is determined that the print or standby mode is set, and the temperature control corresponding to each mode is performed (S108). Since the subsequent steps are the same as those of the first embodiment shown in FIG. 5, duplicated description will be omitted.

In the present invention, the roller rotation is stopped in step S03 in the first embodiment and S102 in the second embodiment. However, the rotation speed is the same as that at the time of printing or lower than that at the time of printing. Good. Further, the upper limit value Ps, the upper limit value Pp, and the upper limit value Pw are not limited to the above values.

The heating source of the fixing roller is not limited to the apparatus of the above-described embodiment, and a halogen heater, a planar heater or the like may be used. In addition, a storage medium that stores the program code of software that realizes the functions of the above-described embodiments is a computer (or C) of a system or an apparatus.
The same temperature control as above can be performed by reading and executing the program code stored in the storage medium by the PU or MPU.

In the above embodiments, the case where the heating device of the present invention is applied to the fixing device has been described. However, the heating device of the present invention performs wrinkling, surface polishing, etc. of the material to be heated. It is also effective to apply it to improve the quality of the material.

[0063]

As described above, according to the present invention,
Temperature measuring means for measuring the temperature of the heating source, electric power supplying means for supplying electric power to the heating source, and controlling the electric power supplying means based on the measured value of the temperature measuring means to control the temperature of the heating source. Since the temperature control means is configured by providing an upper limit value for the power supply to the heating source under a predetermined condition, when the laser printer is in a standby state, the temperature of the heating roller surface is When a sudden temperature change occurs, it is possible to prevent damage to the heating roller due to rapid heating.

According to the present invention, since the predetermined condition is the standby time, there is an effect that the predetermined condition can be easily set.

According to the present invention, since the heating body having the heating source is formed in the shape of a rotating roller, there is an effect that the heating body is uniformly heated all around.
Since the heating element is configured to stop or rotate at a low speed under predetermined conditions, when the laser printer is in the standby state and sudden temperature fluctuations occur on the surface of the heating roller for some reason, the heating roller is heated rapidly. The effect of being able to prevent the damage of.

According to the present invention, temperature measuring means for measuring the temperature of the heating source, electric power supplying means for supplying electric power to the heating source, and controlling the electric power supplying means on the basis of the measured value of the temperature measuring means. And a temperature control means for controlling the temperature of the heating source, and the temperature control means is configured to control ON / OFF of power supply to the heating source at a predetermined value under a predetermined condition. In the standby state, if the temperature of the heating roller suddenly fluctuates for some reason, it is possible to prevent damage to the heating roller due to rapid heating.

According to the present invention, since the predetermined condition is the standby state, there is an effect that the predetermined condition can be easily set.

According to the present invention, since the heating body having the heating source is formed in the shape of a rotating roller, the heating body has the effect that the entire circumference is uniformly heated. Since the heating element is configured to stop or rotate at a low speed under predetermined conditions, when the laser printer is in the standby state and sudden temperature fluctuations occur on the surface of the heating roller for some reason, the heating roller is heated rapidly. The effect of being able to prevent the damage of.

According to the present invention, the recording material on which the toner image is formed is conveyed and passed through the pressure contact portion between the heating body and the pressure body,
In the fixing device that heats and fixes the toner image on the recording material by applying heat and pressure at the time of passing, as the heating body, (1)
Since the heating element of the heating device according to any one of (1) to (8) is applied, there is an effect that the fixing process can be appropriately performed.

According to the present invention, there are provided a toner image forming means for forming a toner image on a recording material and a fixing device for heating and fixing the toner image formed on the recording material by the toner image forming means on the recording material. In the image forming apparatus characterized by including the fixing device of the present invention as the fixing device, it is possible to obtain a high quality fixed image.

According to the present invention, the control means for controlling the power supply to the heating source is configured to store the program which is read and used and which has the upper limit value for the power supply to the heating source under the predetermined condition. By reading the program and performing the heat treatment, there is an effect that the heat treatment can be executed easily and surely.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a fixing device to which a heating device of the present invention is applied.

FIG. 2 is a schematic configuration diagram of a laser printer device to which the fixing device of FIG. 1 is applied.

3 is a block diagram of a basic configuration showing an electric control system of the image forming apparatus of FIG.

FIG. 4 is a flowchart illustrating a temperature control operation of the fixing device according to the first exemplary embodiment of the present invention.

FIG. 5 is a flowchart illustrating a temperature control operation of the fixing device according to the second exemplary embodiment of the present invention.

FIG. 6 is a graph showing the power efficiency of the fixing device.

FIG. 7 is a graph showing applied power values with respect to roller temperature.

[Explanation of symbols]

1 Fixing roller (heater) 2 pressure roller 3 induction coil 4 Temperature sensor 5 coil holder 6 stay 7 cores (magnetic core) 8 Transport guide 9 Unfixed toner image 10 separate nails 11 hollow core 12 Elastic layer 13 Transfer material (recording material) 14 Induction coil assembly 31 Electrophotographic photoconductor (photosensitive drum) 32 charging roller 33 laser scanner 34 Developing device 35 transfer roller 36 Transfer Nip 37 paper feed section 38 paper feed roller 39 Conveyor roller pair 40 top sensor 41 seat path 42 cleaner 43 sheet ejection path 44 Conveyor roller pair 45 discharge roller pair 46 Ejection tray section 47 laser printer 50 AC power supply 51 Power supply unit 52 External I / F processing unit 53 Image processing unit 54 Image memory section 55 Image forming section 56 CPU 57 (I / O) port 58 RAM 59 ROM 60 power value setting signal line 61 Power supply ON / OFF signal line A fixing device L laser beam scanning exposure N Nip part (pressing nip part)

Continued front page    F term (reference) 2H033 AA25 AA32 BA25 BA31 BB03                       BB04 BB06 BB14 BB15 BB18                       BE06 CA05 CA07 CA32 CA40                       CA45 CA48                 3K058 AA22 AA86 BA18 CA12 CA22                       CA61 CA70 CA92 CB02 GA06                 3K059 AA08 AB19 AC33 AC47 AC54                       AC62 AD17 AD25 CD07 CD18                       CD73 CD77

Claims (11)

[Claims] 1. A temperature measuring means for measuring a temperature of a heating source, an electric power supplying means for supplying electric power to the heating source, and a heating means for controlling the electric power supplying means based on a measured value of the temperature measuring means. A temperature control means for controlling the temperature of the heating source, wherein the temperature control means has an upper limit value for supplying electric power to the heating source under a predetermined condition. 2. The heating device according to claim 1, wherein the predetermined condition is a standby time. 3. The heating device according to claim 1, wherein the heating body having a heating source has a shape of a rotating roller. 4. The heating device according to claim 3, wherein the heating element is stopped or rotated at a low speed under a predetermined condition. 5. A temperature measuring unit for measuring the temperature of a heating source, an electric power supplying unit for supplying electric power to the heating source, and a heating unit for controlling the electric power supplying unit based on a measured value of the temperature measuring unit. A heating device for controlling the temperature of the heat source, wherein the temperature control device controls ON / OFF of power supply to the heating source under a predetermined condition. 6. The heating device according to claim 5, wherein the predetermined condition is a standby time. 7. The heating device according to claim 5, wherein the heating body having a heating source has a shape of a rotating roller. 8. The heating device according to claim 7, wherein the heating element is stopped or rotated at a low speed under a predetermined condition. 9. A fixing method in which a recording material having a toner image formed thereon is conveyed and passed through a pressure contact portion between a heating body and a pressure body, and heat and pressure are applied during the passage to heat and fix the toner image on the recording material. In the apparatus, the heating body of the heating device according to any one of claims 1 to 8 is applied as the heating body. 10. An image forming apparatus having a toner image forming means for forming a toner image on a recording material, and a fixing device for heating and fixing the toner image formed on the recording material by the toner image forming means on the recording material. The image forming apparatus according to claim 9, wherein the fixing device according to claim 9 is applied as the fixing device. 11. A storage medium, which stores a program, which is read and used by a control means for controlling power supply to a heating source and which has an upper limit value for power supply to a heating source under a predetermined condition.