JP3094533B2 - Image heating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a rotating endless film and a deviation control means for controlling the deviation of the film in a direction perpendicular to the moving direction of the film to be within a predetermined range. And an image heating apparatus for heating an image on a recording material by heat from the film side.

[0002]

2. Description of the Related Art An image heating apparatus of the above-described film heating type is known from Japanese Patent Application Laid-Open No. 63-313182, and is an image heating fixing apparatus in an image forming apparatus such as an electrophotographic copying machine, a printer and a facsimile. That is, electrophotography
An image forming process such as an electrostatic recording or a magnetic recording may be directly applied to a surface of a recording material (an electrofax sheet, an electrostatic recording sheet, a transfer material sheet printing paper, etc.) using a toner made of a heat-meltable resin or the like. The present invention can be utilized as an image heating and fixing apparatus for performing a heat fixing process on an unfixed visible image (toner image) formed by an indirect (transfer) method and corresponding to target image information as a fixed image on a recording material carrying the image. Further, for example, it can be used as a device for heating a recording material carrying an image to improve the surface properties such as gloss, or a device for performing a temporary deposition process.

[0003] As for the film heating type fixing device, in comparison with other heat fixing type devices such as a heat roller type, a hot plate type, a flash fixing type and an oven fixing type. Since a linear heating element having a low heat capacity can be used as the heating element, and a thin film having a thickness of, for example, about 40 μm can be used as the heating element, it is possible to shorten a rise time to a predetermined fixing temperature and save power. Since the fixing point and the separation point between the film and the recording material can be set separately, toner offset can be prevented.
It has advantages such as solving various drawbacks of other system devices and is effective.

[0004] As described above, an endless type film can be used to rotate and drive the film to be used repeatedly, or an endless roll-wound film can be used by running out. it can.

[0005] In a film heating type heating device using an endless type film, the film moves and moves in the width direction (direction perpendicular to the film rotation direction) during the rotation driving process of the film. Actions are taken to restrict movement.

[0006] In order to control the shift, the ribs and flange members are used to restrict the movement of the film. For example, when the shape of the film-suspending and conveying roller is formed into a crown shape, the film is made of a thin film and is made of a material such as polyimide having low elasticity. In some cases, it is difficult to restrict the shift of the film, and it is difficult to ensure the stable rotation and transport of the film.

In view of the above, a means for detecting a shift position of the film is provided, and when it is detected that the shift to one side in the width direction of the film has reached a predetermined limit position, the shift of the film in the return direction is detected. Activating the means for displacing the film suspension conveyance roller so as to change to the other side in the film width direction, and when it is detected that the shift of the film to the other side in the width direction has reached the predetermined limit position, By providing a film shift control mechanism configured to actuate a means for displacing the film suspension transport roller so as to change the film shift to one side in the film width direction that is the return direction, the rotation drive of the endless film In the process, a shift movement control process is performed in which the shift movement in the film width direction is controlled by reciprocating infinitely within a predetermined range.

[0008]

However, a heating device of a film heating type using an endless film provided with the above-described film-shifting movement control mechanism also has a problem in controlling the film-shifting with the endurance of the device. There is qualitative.

That is, the above-mentioned film shift control mechanism detects the position of the film shift within a certain range, and reciprocates the film within the range to control the shift of the film. When the speed becomes higher, the frequency of reciprocating motion of the film naturally increases, which causes problems such as damage to the film and generation of wrinkles. In addition, when a film detection failure or a driving means for displacing the film-suspending conveyance roller, for example, a solenoid is used, the driving frequency of the solenoid increases, and the solenoid itself may be heated more than necessary. These condition settings can be optimized in the initial state by component accuracy, adjustment, and the like. However, the above-mentioned film shift speed is an unstable factor because a change in durability or the like is expected.

[0010] Particularly, unlike the general film (belt) conveyance, the present apparatus is a heating apparatus.
Since the temperature reaches about 200 ° C., the normal temperature state means that the initial film shift condition changes due to the coefficient of friction of the film transporting means, the surface of the heating element, and the thermal expansion of parts such as the film transport roller. I have to.

It is also known that in a film heating type heating apparatus, a fluorine-based heat-resistant grease is applied to the inner surface of the film as a lubricant because the film is conveyed while sliding with a fixedly supported heating element. However, since this type of grease viscosity has a large temperature dependency, this point is also a factor that makes the conditions near the film unstable.

When the film is always reciprocated in the same area, the wear of the surface of the heating element, the heating element supporting member, and the film transport means may be reduced.

The present invention relates to a film heating type heating apparatus using an endless film, which is provided with the above-mentioned film shift movement control mechanism, and adjusts a change in the film shift in response to an unstable film shift condition. Providing means for stable film shift control and film transport to prevent film detection errors without causing film damage, wrinkles, etc., even if film shift speed changes due to temperature factors, durability changes, etc. The object is to make it possible to improve the reliability of the device.

[0014]

According to the present invention, there is provided an image heating apparatus having the following constitution.

A rotating endless film; and a deviation control means for controlling the deviation of the film in a direction perpendicular to the moving direction of the film to be within a predetermined range. An image heating apparatus for heating an image on a recording material according to claim 1, further comprising means for changing a width of a predetermined range by said shift control means.

<Operation> That is, since the film moving distance range of the film reciprocating motion in the film reciprocating control is variable, even if the film reciprocating speed changes due to temperature factors, durability change, grease distribution, etc., the film reciprocating control reciprocating. The frequency can be kept within a certain range, thereby preventing excessive stress on the film and eliminating wrinkles and the like. In addition, erroneous detection of the film and temperature rise of the solenoid can be minimized, and the displacement of the film, the heating element, and the heating element supporting member can be reduced by abrasion of the same part. Life can be extended. It can be implemented without increasing the size and complexity of the mechanism for controlling the movement of the film, and can realize stable conveyance of the film with respect to the image heating apparatus of the film heating type using the endless film, thereby improving the reliability of the apparatus. .

[0017]

【Example】

<First Embodiment> (FIGS. 1 to 11) FIG. 1 is a plan view of an example of a heating device according to the present invention, which is omitted on the way.
FIG. 2 is a side view, and FIG. 3 is a schematic configuration diagram of an example of an image forming apparatus in which the heating device is incorporated as a fixing device.

(A) Configuration of an Example of Image Forming Apparatus (FIG. 3) The image forming apparatus shown in FIG. 3 is an electrophotographic copying machine of an original plate reciprocating type, a rotating drum type and a transfer type.・ Since the image forming process and the like belong to the public domain, they will be described only briefly.

Reference numeral 52 denotes a reciprocating original table glass disposed on the upper plate 51 of the copier housing 50, which is reciprocally driven in the left and right direction by a drive mechanism (not shown). The original 53 is placed at a predetermined position on the upper surface of the original platen glass 52 with the image surface to be copied facing downward, and is held down by the original pressing plate 54 and set.

The downward image surface of the set original 53 undergoes slit illumination scanning by sequentially passing through the illuminating section 55 during the forward or backward movement of the original table glass 52. Reference numeral 56 denotes an illumination light source.

Then, the downward illumination light of the original surface of the slit illumination light is sequentially imaged and exposed by an imaging lens (short focus imaging element array) 57 on the surface of a photosensitive drum 58 which rotates synchronously with the scanning of the original image.

The photosensitive drum 58 is subjected to a uniform charging process, positive or negative, by a discharger 59 and then subjected to the above-mentioned image forming exposure, so that an electrostatic latent image corresponding to the original image is sequentially formed on the peripheral surface of the drum. Is formed.

Next, the photosensitive drum 58 on which the latent image is formed
The surface sequentially passes the position of the developing device 60 and undergoes sequential development of the latent image. The developed image on the surface of the photosensitive drum 58 reaches the position of the transfer discharger 61 by the subsequent rotation of the photosensitive drum.

On the other hand, the transfer material P
Is fed into the copying machine by the paper feed roller 63, and the leading end is received at the nip portion of the registration roller pair 64 which is in a rotation stopped state at that time. Here, the photosensitive drum 5
The rotation of the registration roller pair 64 is started at a predetermined timing synchronized with the rotation of the rotation of the transfer roller 8, whereby the transfer material P is guided by the guide member and fed toward the photosensitive drum 58, and is transferred to the photosensitive drum 58. The developed image on the surface of the photosensitive drum 58 is sequentially transferred to the transfer material P introduced into the transfer section between the discharge units 61 for use.

The copy material P having received the image transfer is a photosensitive drum 58
The transfer device 6 is sequentially separated from the surface by a separation unit (not shown).
5, the image is introduced into the fixing device 1, and the image is fixed.
It is discharged to 7.

After the image is transferred, the surface of the photosensitive drum 58 is cleaned by a cleaning device 68 and repeatedly used for image formation.

(B) Fixing device 1 (FIGS. 1 and 2) In FIGS. 1 and 2, reference numerals 13 and 12 denote a pair of left and right endless film driving rollers and a driven roller serving also as a tension roller, which are disposed substantially in parallel with each other. Reference numeral 11 denotes an endless film suspended and stretched between the two rollers 13 and 12. The drive roller 13 is rotated in a clockwise direction as indicated by an arrow a by a drive system including a drive motor 27. It is rotationally driven at a predetermined peripheral speed in the direction.

The film 11 is a heat-resistant film having a total thickness of 100 μm, more preferably less than 40 μm. In this embodiment, an endless film having a thickness of about 20 μm such as polyimide, polyetherimide, PES, PFA or the like as a base film and a release layer of PTFE or the like coated on the image contact surface by about 10 μm.

Reference numeral 14 denotes a heating element which is fixedly disposed (fixed and supported by a fixing device) on the inner surface side of the descending film portion of the endless film 11 described above. This heating element is a film 11
Is a low-heat-capacity linear heating element (hereinafter, referred to as a heater) having a length in the direction intersecting the surface movement direction, that is, the film width direction, and generates heat when energized.

Reference numeral 15 denotes a pressure roller having a rubber elastic layer of silicon rubber or the like having good releasability, and a biasing portion (not shown) sandwiching the film portion of the endless film 11 between the heater 14 and the descending side. By means, for example, total pressure 4-5kg
, And rotates in the film moving direction in the forward direction at the same peripheral speed as the film speed as the film moves.

A transfer material P carrying an unfixed toner image t (heat-fusible toner) on the upper surface of the transfer material P transported from the transfer unit 61 (FIG. 3) to the fixing device 1 by the transport device 65 sandwiches the endless film 11. The unfixed image surface enters between the film 11 and the pressure roller 15 of the pressure contact portion (fixing nip portion) N formed by the heater 14 and the pressure roller 15 so that the unfixed image surface becomes the transfer material P.
At a speed substantially the same as the transport speed of the film 11, and passes through the fixing nip N while receiving the clamping pressure in a state of being overlapped with the film 11 in a plane moving state in the same direction. In this process, the toner image bearing surface of the transfer material P is heated by receiving the heat of the heater 14 via the film 11, and the toner image t is completely softened and melted at least in the surface layer portion, and is thermally fixed to the transfer material P surface. . The transfer material P that has passed through the fixing nip portion N is separated from the surface of the film 11 at the curvature of the film 11 along the roller 13 when the transfer material P passes through the position of the film drive roller 13.

(C) Film shift control mechanism (FIG. 1)
FIG. 6) The drive roller 13 and the driven roller 12 of the endless film 11 are disposed between the front side plate 19 and the rear side plate 18 of the fixing device 1 as shown in FIG. 21
Reference numeral 20 denotes a front end bearing and a rear end bearing of the driven roller 12.

Here, the driving roller 13, the driven roller 12,
The parallelism of the heater 14 and the pressure roller 15 (X-axis direction,
Unless the accuracy in the (Y-axis direction, Z-axis direction) is set to ± 0, when the drive roller 13 is driven to rotate the film 11 in the direction of arrow a, the film 11 Due to the positional relationship (variation in the X, Y, and Z axes) of the three members of the rollers 13 and 12 and the heater 14, the length of the rollers 13 and 12 is longer than the initial position of the film 11 shown by the solid line in FIG. Is shifted to the right or left in the film width direction along the side plate 18 or the side plate 18 or the side plate 19.
In this case, the edge of the film may be rubbed and damaged.

Therefore, in the present embodiment, the driven roller 1
2 is supported on the side plate 18 with a degree of freedom of movement in the front and rear directions of arrows A and B with respect to the side plate 18, and is normally urged to move in the forward direction A by the compression spring 22 as indicated by the solid line. At the first position, it is received by a stopper (not shown), and the plunger of the solenoid 23 is connected. When the energization of the solenoid 23 is turned on, the bearing 20 is pulled in the retreating direction B against the compression spring 22. Then, the position is displaced to the second position indicated by the two-dot chain line.

That is, energization ON / OFF of the solenoid 23
Thus, the degree of parallelism of the driven roller 12 with respect to the driving roller 13 and the heater 14 can be changed.

In this embodiment, when the solenoid 23 is off and the bearing 20 is at the first position shown by the solid line, the rotating film 11
Moves toward the left side in the film width direction, that is, toward the far end side of the rollers 13 and 12 along the length of the suspended tension members 13, 12 and 14 along the length thereof. Is in the second position shown by the two-dot chain line, the rotating film 11 moves to the right in the film width direction, that is, toward the front ends of the rollers 13 and 12, in contrast to the above.

Numeral 16 denotes a photosensor for detecting the position of the film shift. Also, as shown in FIG. 1, the front end 3 of the film 11 is masked as indicated by hatching so as to block the light of the photosensor 16 around the entire edge.

In this embodiment, a photo-interrupter is used for the photosensor 16. However, when a reflection-type photosensor is used here, the end portion 3 of the film 11 is treated with a reflection member that reflects light. is necessary. Alternatively, the image may be read by a photo sensor via a movable piece that moves along the edge of the film 11.

In this embodiment, the processing such as masking is performed only on one end of the film 11, but it goes without saying that the processing may be performed on the entire film.

Reference numeral 4 denotes a film edge cleaning member. The film edge is always cleaned so as to prevent erroneous reading when a reflection type sensor is used due to contamination of the film edge. Is what it is. In the present embodiment, felt is used, but any type may be used as long as it has a cleaning effect.

FIG. 4 shows the outer shape of the film 11. This film is an endless belt as described above, and its diameter is φM. Also, as shown in the figure, film 1
One end (the front end) of 1 is cut diagonally,
Let the length of the longest part be Lmax and the length of the shortest part be Lm
If in, the dimension of the obliquely cut portion (oblique cut portion) of the film 11 is obtained by Lmax-Lmin, and is set to ΔL (the oblique cut amount of the film) here. The oblique cut portion is arranged on the front side of the main fixing device as shown in FIG. 1 so that the photo sensor 16 detects the position of the film 11.

FIG. 5 is a detailed view of the positional relationship between the photo sensor 16 and the film 11. In this embodiment, the photo sensor 1
A transmission type photo-interrupter is used for 6 and its detection position is indicated by b. This is film 11
Is on the back side of the position b, the photo sensor 16 is ON
In the case of being on the near side of the position b, the switch is turned off. Further, the oblique cut portion of the film 11 is configured to be at the position of the detection position b.

That is, the film 11 is formed by the arrow a shown in FIG.
The photo sensor 16 is turned to O
N / OFF is repeated, and the ON / OFF cycle ratio (duty) depends on the film position (deviation position).
Ratio) will be variable.

The film position shown in FIG.
6 represents a reference position where the center of the oblique cut portion of the film 11 is located at the detection position b. The film position and OFF of the photo sensor 16 are centered on the reference position of the film.
The relationship of time is shown in the graph of FIG.

As shown in FIG. 6, when the film 11 is at the reference position b, the OFF time of the photosensor 16 is c seconds, and the film 11 is located at least ΔL / 2 or more in front of the reference position b. At this time, the OFF time of the photo sensor 16 is 0 second.

Conversely, when the film 11 is located at least ΔL / 2 behind the reference position b, the photo sensor 16 is kept off.

Here, the OF in the case where the shift position of the film 11 is immediately before the position where the photo sensor 16 is kept turned off.
The F time is d seconds, which can be considered to be substantially the same as the time for the film 11 to make one round, and the OFF time c seconds at the reference position b is the center of the film oblique cut portion. The time is almost half of d seconds.

(D) Film-Side Movement Control Circuit (FIG. 7) FIG. 7 is a schematic diagram of a control system.

Reference numeral 26 denotes a microcomputer, and the photo sensor 16 is connected to an input terminal IN1 of the microcomputer. A solenoid 23 is connected to the output terminal OUT1. The output terminal OUT2 outputs a rotation control signal of the motor 27 for driving the fixing device.

A +5 V power supply is connected to the VDD terminal.
The GND terminal is connected to the ground.

Although not shown, a terminal for other input signals and output signals of a copying machine using the present fixing device is provided, and a microcomputer 26 has a copying operation system for the copying machine. A built-in non-volatile RAM, which retains its stored contents even when power supply to the microcomputer 26 is cut off, together with a ROM and a RAM in which a can program and the like are programmed.

Reference numeral 28 denotes a switch for switching a film shift control range. In this embodiment, the switch 28 is turned off.
(The input terminal IN2 of the microcomputer 26)
Control is performed in the first shift control range, and when the switch 28 is ON (when the input terminal IN2 is “H”).
(L ") The film shift control is performed in the second shift control range.

Here, the first deviation control range and the second deviation control range have a relationship of first deviation control range> second deviation control range.

(E) Control Program (FIGS. 8 to 11) FIGS. 8 to 11 show flowcharts of a film shift movement control program of the fixing device.

This program is also programmed in the built-in ROM in the microcomputer 26, and is called and executed at regular time intervals or as needed by a main sequence program or the like. It has become.

First, after the start, in step 1 (FIG. 8), it is determined whether or not the motor 27 is ON. If the motor 27 is ON, the process proceeds to step 2, and a subroutine for determining the film deviation control range based on the paper size (transfer material width size) is called. If the motor 27 is off, the process returns to step 1 and waits until the motor 27 is turned on.

Next, in step 2, it is determined whether or not the film has been controlled so as to approach the front side. This means that the content of a predetermined address in the nonvolatile RAM in the microcomputer 26 is set as a near side flag, and when the state of the memory is 1, that is, when the memory has been controlled to the near side, the step is performed. Step 3 is performed, the solenoid 23 is turned on, and the deviation control is set to the near side.
Move to. In step 2, the front flag is set to 0.
In the case of, since the film has been controlled so as to be shifted to the far side, the process proceeds to step 4 as it is.

At step 4, it is determined whether or not the sensor 16 is off. If the sensor 16 is on, the process proceeds to step 8, and if it is off, the process proceeds to step 5.

In step 5, the value of the error timer is reset to 0, measurement is started, and the process proceeds to step 6.

In step 6, it is determined whether or not the sensor 16 is ON. If not, the process proceeds to step 7.

In step 7, an error check routine is executed, and the process returns to step 6.

Here, the contents of the error check routine will be described with reference to FIG.
It is determined whether or not 7 is ON. If ON, the process proceeds to step S2.
Move to (FIG. 9).

In step S2, it is determined whether or not the error timer value is greater than d seconds. If the error timer value is less than d seconds, the process proceeds to the exit of this routine. If the error timer value is greater than d seconds in step S2, step S
It will shift to 3. In step S3, an error flag is set, and the routine goes to the exit of this routine.

Next, at step 6, the sensor 16
If N, the process proceeds to step 8 to reset the value of the error timer to 0, start the measurement, and proceed to step 9. In step 9, it is determined whether or not the sensor 16 is OFF. If the sensor 16 is not OFF, the process proceeds to step 10 to execute an error check routine and returns to step 9, and if the sensor 16 is turned off, the process proceeds to step 11. Then, the value of the timer 1 is reset to 0 and the measurement is started, and the process proceeds to step 12 (FIG. 9).

In step 12, it is determined whether or not the motor 27 is ON. If the motor 27 is ON, the process proceeds to step 14.

At step 14, it is determined whether or not the sensor 16 is ON.
The process proceeds to step 5 to execute an error check routine, and returns to step 14. If it is ON, the process proceeds to step 27.

In step 27, it is determined whether or not the above-mentioned film shift control changeover switch 28 is ON.

In this embodiment, the first shift control range is d / 4 to 3d / 4, and the second shift control range is 2d / 5 to 3d / 5. If the switch 28 is ON in step 27, the process proceeds to step 28 to perform control in the second shift control range, and if not, the process proceeds to step 16 to perform control in the first shift control range.

In step 28, the measured value of the timer 1 is 2d
A comparison is made to determine whether or not the time is shorter than / 5 seconds. If the time is shorter, it can be determined that the film 11 is located on the front side of the second shift control range. The approach direction of the film 11 is switched to the back side, the front flag is reset to 0, and the process proceeds to step 20.

If it is determined in step 28 that the value measured by the timer 1 is not smaller than 2d / 5 seconds, the process proceeds to step 29.

In step 29, the measured value of the timer 1 becomes 3
It is comparing whether it is larger than d / 5 seconds,
If it is not larger, the process proceeds to step 20. If it is larger, it can be determined that the film 11 is located on the far side of the second shift control range.
3 is turned on to switch the direction of shifting of the film 11 to the near side, the foreground flag is set to 1, and the routine proceeds to step 20.

In step 16, the measured value of timer 1 is set to d /
A comparison is made as to whether the time is less than 4 seconds. If the time is smaller than 4 seconds, it can be determined that the film 11 is located closer to the front side than the first shift control range. The direction of the approach 11 is switched to the back side, the front flag is reset to 0, and the process proceeds to step 20.

If the measured value of the timer 1 is not smaller than d / 4 seconds in step 16, the process proceeds to step 18.

At step 18, the value measured by the timer 1 becomes 3
It is comparing whether it is larger than d / 4 seconds,
If it is not larger, the process proceeds to step 20. If it is larger, it can be determined that the film 11 is located farther than the first shift control range.
3 is turned on to switch the direction of shifting of the film 11 to the near side, the foreground flag is set to 1, and the routine proceeds to step 20.

In step 20, the value of the error timer is reset to 0 and measurement is started, and the process proceeds to step 21.

At step 21, it is determined whether or not the sensor 16 is OFF. If the sensor 16 is not OFF, the process proceeds to step 22, executes an error check routine, and returns to step 21.

In step 21, the sensor 16
In the case of FF, the process proceeds to step 23, where the value of the timer 1 is reset to 0, measurement is started, and the process returns to step 12.

In step 12 described above, the motor 27
In the case of the FF, the process proceeds to step 13, where the measurement of the timer 1 is stopped, the measured value is reset to 0, the solenoid 23 is turned off, and the process returns to step 1.

FIG. 11 shows a flowchart of a film abnormality processing program which is a part of the main program. Here, it is determined in step 24 whether or not the error flag is set. If the error flag is not set, the process proceeds to the exit and the next main sequence program is executed.

If the error flag is set in step 24, the flow goes to step 25 to turn off all outputs of all the devices (copying device in this embodiment), and then goes to step 26 to move to the film An abnormality is displayed and the step 26 is set as a permanent loop so that the main program cannot be executed.

As described above, the endless film 11 of the present fixing device starts from the time of rotation of the motor, and stores the non-volatile R in which the shift direction previously controlled is stored.
The solenoid 23 is controlled according to the content of AM. Next, when the sensor 16 is ON when the motor is rotating, wait until the sensor 16 is turned OFF, and when the sensor 16 is OFF, wait until the sensor 16 is turned ON and then wait until the sensor 16 is turned OFF. The timing of switching to OFF is detected, and the initial setting ends. Then, the position of the film 11 is detected only by measuring the OFF time of the sensor 16 until the sensor 16 switches from OFF to ON.

Thereafter, the OFF time of the sensor 16 from the timing when the sensor 16 switches from ON to OFF to the time from OFF to ON is measured, and the film position is determined.
The control is performed so as to be within a predetermined control range specified by the switch 28.

In this embodiment, a transmission type photo sensor is used as the sensor 16, but it goes without saying that the same applies to a sensor such as a microswitch or a reflection type photo sensor.

Further, a plurality of switches may be provided so that the film-side control range can be switched to a plurality of switches.

<Second Embodiment> (FIGS. 12 to 14) FIG. 12 is a schematic diagram of a control system according to a second embodiment. The configuration of the example of the image forming apparatus, the fixing device, and the mechanism for controlling the shift of the film shift is the same as that of the first embodiment.

In FIG. 12, reference numeral 29 denotes a microcomputer, and the photo sensor 1 is connected to an input terminal IN1 of the microcomputer.
6 are connected. A solenoid 23 is connected to the output terminal OUT1. The output terminal OUT2 outputs a rotation control signal of the motor 27 for driving the fixing device.

A power supply of +5 V is connected to the VDD terminal.
The GND terminal is connected to the ground.

Although not shown, other input and output signal terminals of the copying machine using the present fixing device are provided, and a microcomputer 29 is provided with a copying operation system for this copying machine. -In addition to a ROM and a RAM in which a can program and the like are programmed, a non-volatile RAM which does not lose its stored contents even when the power supply to the microcomputer 29 is cut off is built in.

Reference numeral 30 denotes a control range changeover switch closer to the rear side of the film, and reference numeral 31 denotes a control range changeover switch closer to the front side. When the switches 30 and 31 are OFF (when the input terminals IN2 and IN3 are "H"). , Each first
When the switches 30 and 31 are ON (when the input terminals IN2 and IN3 are "L"), the second
Is controlled in the shift control range.

FIGS. 13 and 14 show flowcharts of a program for controlling the movement of the fixing device toward the film.

This program is also programmed in the above-mentioned built-in ROM in the microcomputer 29, and is called and executed by a main sequence program or the like at regular time intervals or as needed. It has become.

First, after the start, in step 101, it is determined whether or not the motor 27 is ON. If the motor 27 is on, the process proceeds to step 102. If the motor 27 is off, the process returns to step 101 and waits until the motor 27 is turned on.

Next, at step 102, it is determined whether or not the film has been controlled so as to approach the front side. This means that the content of a predetermined address in the nonvolatile RAM in the microcomputer 29 is set as a near side flag, and when the state of the memory is 1, that is, when the memory has been controlled to the near side, the step is performed. The program proceeds to 103, turns on the solenoid 23, sets the deviation control to the near side, and proceeds to step 104. If the front side flag is 0 in step 102, the film has been controlled so as to be shifted to the far side, so that the process proceeds to step 104 as it is.

In step 104, it is determined whether or not the sensor 16 is OFF. If the sensor 16 is ON, the process proceeds to step 108;
Go to 5.

In step 105, the value of the error timer is set to 0.
And the measurement is started, and the routine proceeds to step 106.

In step 106, it is determined whether or not the sensor 16 is ON. If not, the process proceeds to step 107.

Next, at step 106, the sensor 16
If is ON, the process proceeds to step 108, where the value of the error timer is reset to 0, and measurement is started.
Move to 09. In step 109, the sensor 16 is turned off.
If it is not OFF, the process proceeds to step 110 to execute an error check routine and returns to step 109. If the sensor 16 is turned off, the process proceeds to step 111 and the value of the timer 1 is reset. At the same time, the measurement is reset to 0, and the process proceeds to step 112 (FIG. 14).

In step 112, it is determined whether or not the motor 27 is ON.
Move to 4.

At step 114, it is determined whether or not the sensor 16 is ON. If the sensor 16 is not ON, the process proceeds to step 115 to execute an error check routine and returns to step 114. If it is ON, the process proceeds to step 124. .

In step 124, it is determined whether or not the near side control changeover switch 31 is ON. Step 1
If the switch 31 is ON at 24, the process proceeds to step 125, and if not, the process proceeds to step 116.

In step 125, the value measured by the timer 1 is 2
A comparison is made as to whether or not the time is smaller than d / 5 seconds. If the time is shorter than the time, it can be determined that the film 11 is located on the near side with respect to the near side second control range.
7, the solenoid 23 is turned off, the approach direction of the film 11 is switched to the back side, the front flag is reset to 0, and the process proceeds to step 120. If it is determined in step 125 that the value measured by the timer 1 is not smaller than 2d / 5 seconds, the process proceeds to step 126.

At step 116, the measured value of timer 1 is set to d.
A comparison is made as to whether or not the time is shorter than / 4 second. If the time is shorter than this, it can be determined that the film 11 is positioned on the near side with respect to the first control range on the near side.
Then, the solenoid 23 is turned off to switch the approach direction of the film 11 to the back side, the front flag is reset to 0, and the process proceeds to step 120. Step 1
If the measured value of the timer 1 is not smaller than d / 4 seconds at 16, the process proceeds to step 126.

In step 126, it is determined whether or not the rear side control changeover switch 30 is ON. Step 12
If the switch 30 is ON in step 6, the process proceeds to step 127; otherwise, the process proceeds to step 118.

At step 127, the measured value of timer 1 becomes 3
It is comparing whether it is larger than d / 5 seconds,
If it is not large, the process proceeds to step 120. If it is large, it can be determined that the film 11 is located on the back side of the back side second deviation control range. Switch the direction to the near side, set the foreground flag to 1,
Move to step 120.

In step 118, the value measured by the timer 1 is 3
It is comparing whether it is larger than d / 4 seconds,
If it is not large, the process proceeds to step 120. If it is large, it can be determined that the film 11 is located on the back side of the back side first deviation control range. Switch the direction to the near side, set the foreground flag to 1,
Move to step 120.

At step 120, the value of the error timer is set to 0.
The measurement is started together with resetting to
Move to.

In step 121, it is determined whether or not the sensor 16 is OFF. If the sensor 16 is not OFF, the process proceeds to step 122, executes an error check routine, and returns to step 121.

If the sensor 16 is OFF in step 121, the process proceeds to step 123, where the value of the timer 1 is reset to 0, measurement is started, and the process returns to step 112.

If the motor 27 is turned off in step 112, the process proceeds to step 113.
And stop the measurement, reset the measurement value to 0,
Next, the solenoid 23 is turned off, and the process returns to step 101.

The film abnormality processing is the same as in the first embodiment. At this time, the shift control range in which the switches 30 and 31 are switched becomes like a joint.

When the switch 30 is OFF and when the switch 31 is OFF, d / 4 to 3d / 4 seconds When the switch 30 is OFF and when the switch 31 is ON, 2d / 5 to 3d / 4 seconds When the switch 30 is ON, the switch 31 is OFF D / 4 to 3d / 5 seconds Switch 30 = ON, 31 = ON 2d / 5 to 3d / 5 seconds <Third embodiment> (FIGS. 15 to 17) In this embodiment, the film position is detected. It is another example of the means.

FIG. 15 is a plan view of the fixing device 1 in which an intermediate portion is omitted. Components and portions common to those of the above-described device of FIG. 1 are denoted by the same reference numerals, and the description thereof will not be repeated.

103, 104, 105, 106, 107
A photo sensor 108 detects the position of the film.

The sensors 105 and 106 are the sensor 103
The sensor 107.1 is installed so as to detect the film position inside the film detection position of 104.
Reference numeral 08 is provided to detect a film position outside the film detection position of the sensors 105 and 106.

The both ends 3 and 3 'of the film 11 are masked so as to block the light of the photo sensor.

In this embodiment, a photo-interrupter is used as a photosensor. However, when a reflection-type photosensor is used here, both ends 3.3 of the film 11 are used.
The part 'needs a reflection member treatment to reflect light. Further, in this embodiment, the processing such as masking is performed only on both ends, but it goes without saying that the processing may be performed on the entire film. Alternatively, the image may be read by a photo sensor via a movable piece that moves along the edge of the film.

Reference numerals 101 and 102 denote film edge cleaning members which constantly clean the edge of the film so as to prevent erroneous reading when a reflection type sensor is used due to contamination of the edge of the film. is there. In the present embodiment, felt is used, but any type may be used as long as it has a cleaning effect.

Next, a schematic diagram of the electric control is shown in FIG. 1
09 is a microcomputer which has input terminals IN1 and IN1,
IN2, IN3, IN4, IN5, and IN6 have the photosensors 103, 104, 105, and 106, respectively.
107 and 108 are connected, and a motor rotation control signal for driving the present fixing device is output to OUT2. A solenoid 23 is connected to OUT1.

A shift control range changeover switch 110 is connected to the input terminal IN7, and the microcomputer 109 switches the shift control range based on the information of the input terminal IN7. That is, the switch 110 is turned off (input terminal 7
Is "H"), the first shift control range (sensor 105
・ Use 106) and switch 110 is ON
When the input terminal IN7 is “L”, the control is switched to the second shift control range (using the sensors 103 and 104).

Although not shown, the microcomputer 109 has terminals for other input signals and output signals of the copying machine using the present fixing device 1. The microcomputer 109 has a built-in ROM and RAM in which a copying operation sequence program and the like of the copying machine are programmed.

FIG. 17 is a flowchart showing a control sequence for shifting the film by the microcomputer 109. This is programmed in the built-in ROM of the microcomputer 109 similarly to the first embodiment, and is called and executed by a main sequence program or the like at regular time intervals or as needed.

First, after the start, in step 201, it is determined whether or not the motor 27 is ON. If the motor 27 is on, the process proceeds to step 202. If the motor 27 is off, the solenoid of step 208 is turned off without performing the shift control, the back flag is set, and step 210 is performed.
Exit and return to the main program.

Next, in step 202, it is determined whether or not the film is nearer. This means that the content of a predetermined address on the RAM in the microcomputer 109 is set as a back side flag, and the state of the memory is 1 or 0.
Have been determined. If the film is approaching the back, that is, if the back flag is 1, the process proceeds to step 203.

In step 203, the sensor 108
Judgment as to whether or not N is made, and the sensor 108 is ON
If not, the process proceeds to step 211.

At step 211, the switch 110 is turned on.
It is determined whether or not. If switch 110 is ON, the second
The process moves to step 212. If the switch 110 is not ON, it is in the first control range, and the process proceeds to step 204.

At step 212, the sensor 103 is turned on.
Is determined, and if it is ON, step 2
Move to 05.

In step 205, since the film has come to the back to the second control range and the sensor 103 has been turned on, the solenoid 2 is operated to move the film to the near side here.
At the same time, the back side flag is reset and the process proceeds to the exit of step 210.

In step 212, the sensor 103
If is not ON, the process directly proceeds to the exit of step 210.

At step 204, the sensor 105 is turned on.
Is determined, and if it is ON, step 2
Move to 05.

[0130] In step 205, since the film is located farther than the first control range, the sensor 105 is turned on.
Therefore, the solenoid 23 is turned on so as to move the film toward the near side, and at the same time, the rear side flag is reset, and the process proceeds to the exit of step 210.

At step 204, the sensor 10
If 5 is not ON, the process proceeds to the exit of step 210 as it is.

In step 203, the sensor 108
Is ON, that is, if the film has moved further to the front side in spite of the fact that it is controlled to move to the far side, the process proceeds to step 209 and the film abnormality flag is set. The process proceeds to step 208, where the solenoid 23 is turned off, the back side flag is reset, the process proceeds to step 10, and the process returns to the main sequence.

Similarly, in step 202, if the film is approaching the front side, that is, if the back side flag is 0, the process proceeds to step 206.
In step 206, it is determined whether or not the sensor 107 is ON. If the sensor 107 is ON, that is, if the film has moved further to the rear side despite the fact that the film is moving to the front side, Step 2
09, and returns to the main program in the same manner as described above.

In step 206, the sensor 1
If 07 is OFF, the process proceeds to step 213 to determine whether the switch 110 is ON.

If the switch 110 is ON, it is in the second control range, and the routine goes to step 214. If it is not ON, it is the first control range, and the routine goes to Step 207.

At step 214, it is determined whether or not the sensor 104 is ON. Here the sensor 104 is O
If it is not N, the process directly proceeds to step 210 and returns to the main program. If the sensor 104 is ON, the process proceeds to step 208 to turn off the solenoid 23 and switch the control so that the film moves to the back side. , The back side flag is set, and the routine proceeds to step 210 to return to the main program.

At step 207, it is determined whether or not the sensor 106 is ON. Here, the sensor 106 is O
If it is not N, the process directly proceeds to step 210 and returns to the main program. If the sensor 106 is ON, the process proceeds to step 208 and the solenoid 23 is turned off.
Then, the control is switched so as to shift the film toward the back side, and at the same time, the back side flag is set, and the routine proceeds to step 210 to return to the main program.

The error processing is the same as in the first embodiment.

Further, as in the second embodiment, a switch for changing the control range on the rear side and a switch for changing the control range on the front side may be provided separately. In the control flow at this time, in FIG. 17, the switch in step 213 and the switch in step 211 are a front-side switch and a rear-side switch, respectively, and the other operations are the same.

<Fourth Embodiment> (FIGS. 18 and 19) This embodiment is the configuration and control flow of another electric control system according to the third embodiment. In the control system of FIG. 18, reference numeral 111 denotes a microcomputer, which has input terminals IN1 to IN1.
4, signals from the photosensors 103 to 108 are input. A signal from the photosensors 103 and 105 selected by the switch 112 is input to the input terminal I1.
The signals of the photosensors 104 and 106 selected by the switch 112 are input to N2. Others are the same as the third embodiment.

As shown in FIG. 15, the sensor 103.1
Since the sensors 105 and 106 detect the outer film position from the position 04, the shift control of the film can be switched by switching the input signal of the microcomputer 111 by the switch 112 in FIG.
Also, the switch 112 does not have to be linked as shown in FIG. 18, but may be switched independently.

Hereinafter, a deviation control flow of the microcomputer 111 will be described with reference to FIG. This is similar to the first embodiment.
M and is called and executed by a main sequence program or the like at regular time intervals or as needed.

First, after the start, in step 301, it is determined whether or not the motor 27 is ON. If the motor 27 is on, the process proceeds to step 302. If the motor 27 is off, the solenoid of step 308 is turned off without performing the shift control, the back side flag is set, and the exit of step 310 is performed. And return to the main program.

Next, in step 302, it is determined whether or not the film is nearer. This means that the contents of a predetermined address on the RAM in the microcomputer 111 are set as a back side flag, and the state of the memory is 1 or 0.
Have been determined. If the film is moving to the back, that is, if the back flag is 1, the process proceeds to step 303.

In step 303, the sensor 108
Judgment as to whether or not N is made, and the sensor 108 is ON
If not, the process proceeds to step 304.

In step 304, the input port IN1 is set to O
A determination is made as to whether or not the number is N. If it is ON, the process proceeds to step 305.

In step 305, since the film is approaching the back and the sensor is turned on, the solenoid 23 is turned on so that the film is brought closer to the front side, and at the same time, the back side flag is reset and the process proceeds to the exit in step 310. Will be.

In step 304, the input port IN
If 1 is not ON, the process proceeds to the exit of step 310 as it is.

At step 303, the sensor 108
Is ON, that is, if the film is further moved to the front side despite the fact that it is controlled to move to the back side, the process proceeds to step 309 and the film abnormality flag is set, and The flow shifts to 308, the solenoid 23 is turned off, the far side flag is reset, the flow shifts to step 310, and the flow returns to the main sequence.

At the same time, in step 302, if the film is approaching the near side, that is, if the back side flag is 0, the process proceeds to step 306.

At step 306, the sensor 107 is turned on.
And if the sensor 107 is ON,
That is, if the film has moved further to the rear side irrespective of the fact that the film is going to move to the front side, the process proceeds to step 309 and returns to the main program in the same manner as described above.

In step 306, the sensor 1
If 07 is OFF, the process proceeds to step 307 to determine whether or not the input terminal IN2 is ON. If the input terminal IN2 is not ON, step 3
10 and return to the main program.
If N2 is ON, the process proceeds to step 300, in which the solenoid 23 is turned off, the control is switched so as to move the film toward the back side, and at the same time, the back side flag is set and the process proceeds to step 310, where the main program is executed. I will return.

<Fifth Embodiment> (FIGS. 20 to 22) This embodiment is still another embodiment of the film position detecting means.

In this embodiment, as shown in FIG. 20, the shift control range is switched by moving the photosensors 105 and 106 in a direction perpendicular to the side plates 18 and 19. That is, the photo sensors 105 and 106 can move along a rail (not shown) provided in a direction perpendicular to the side plates 18 and 19.
113 and 114 are solenoids, and the photo sensor 1
It is for the movement of 05.106. Solenoid 113/11
When 4 is ON, the photo sensors 105 and 106 detect the outer film position.

In the electric control system shown in FIG. 21, reference numeral 115 denotes a microcomputer which has input terminals IN1 and IN2.
・ IN3 ・ IN4 have photo sensor 105 ・
106, 107 and 108 are connected and the output terminal O
A motor rotation control signal for driving the fixing device is output to UT1. A solenoid 23 is connected to the output terminal OUT2, and solenoids 113 and 114 are connected to the output terminals OUT3 and OUT4, respectively. Reference numeral 110 denotes a shift control range switching switch which is turned on (IN5
Are "L"), the solenoids 113 and 114 are turned off. If switch 110 is not ON, solenoid 11
3 ・ 114 is turned ON.

When the solenoids 113 and 114 are ON,
The photo sensors 105 and 106 move outward along the rail. By doing so, the photo sensors 105 and 106 can be moved in the vertical direction to the side plates 18 and 19 by the switch 110, and the shift control range can be switched.

The control flow of the shift control is described in the fourth section.
This is the same as the embodiment.

Also, as shown in the control system of FIG.
The switching may be performed by directly turning on / off the drive current.

Further, two switches are provided so that the solenoid 11
3. 114 may be switched independently. A lever may be provided instead of the switch, and the photosensor may move on the rail via the link according to the movement of the lever.

[0160]

As described above, according to the present invention, in a film heating type image heating apparatus using an endless film, the reciprocating movement distance of the film in the film shift control is variable. Due to the grease distribution, etc., it is possible to keep the reciprocation frequency of film deviation control within a certain range even if the film deviation speed changes.
This can prevent excessive stress on the film and eliminate wrinkles and the like. In addition, erroneous detection of the film and temperature rise of the solenoid can be minimized.
Since the sliding wear of the same portion of the heater supporting member is reduced, the life of the entire apparatus can be extended. It can be implemented without increasing the complexity and size of the film shift control mechanism, and can achieve stable film transport for film heating type image heating devices using endless films.
The reliability of the device could be improved.

[Brief description of the drawings]

FIG. 1 is a partially omitted plan view of an example of a heating device according to the present invention.

Fig. 2 Side view

FIG. 3 is a schematic configuration diagram of an example of an image forming apparatus using the heating device as a fixing device.

Fig. 4 Outline drawing of endless film

FIG. 5 is a diagram showing a relationship between a film sensor and a film position.

FIG. 6 is a graph showing a relationship between a film position and a film sensor output.

FIG. 7 is a schematic diagram of a control system.

FIG. 8 is a flowchart of a film shift movement control program.

FIG. 9 is a flowchart of a film shift movement control program.

FIG. 10 is a flowchart of a film shift control program.
Chart

FIG. 11 is a flowchart of a film shift control program.
Chart

FIG. 12 is a schematic diagram of a control system according to a second embodiment.

FIG. 13 is a flowchart of a film shift control program.
Chart

FIG. 14 is a flowchart of a film shift control program.
Chart

FIG. 15 is a partially omitted plan view of the heating device according to the third embodiment.

FIG. 16 is a schematic diagram of a control system.

FIG. 17 is a flowchart of a control program.

FIG. 18 is a schematic diagram of a control system according to a fourth embodiment.

FIG. 19 is a flowchart of a control program.

FIG. 20 is a plan view of a heating device according to a fifth embodiment, which is omitted on the way.

FIG. 21 is a schematic diagram of a control system.

FIGS. 22A and 22B are schematic diagrams of other control systems.

[Explanation of symbols]

Reference Signs List 11 endless film fixing sheet 12 driven roller 13 drive roller 14 fixing heater 15 pressure roller 16.103 to 108 photosensor 23.113.114 solenoid 26.29.109.111.115 microcomputer 27 motor 28.30.31. 110 changeover switch

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 15/20 G03G 15/16 G03G 15/00 510

Claims (1)

(57) [Claims] 1. A rotating endless film, a shift control means for controlling a shift of the film in a direction perpendicular to a moving direction of the film to be within a predetermined range,
An image heating apparatus for heating an image on a recording material by heat from the film side, further comprising: a unit for changing a width of a predetermined range by the shift control unit.