JPH0444077A - image heating device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides a heat-resistant film that is brought into pressure contact with a heating element and driven to move, and a recording material that supports a microscope image is placed on the side opposite to the heating element side. By introducing the heating element into close contact with the film and passing it through the heating element position, the heat from the heating element is transferred to the recording material through the film! This invention relates to a heating device using the Moe method (film heating method).

This device is an image heating fixing device in an image forming device such as an electrophotographic copying machine, a printer, or a fax machine, that is, a heat-melting resin, etc. Recording materials (transfer material sheets, electrofax sheets,
An unfixed toner image corresponding to the desired image information, formed by an indirect (transfer) method or a direct method on the surface of an electrostatic recording sheet, printing paper, etc., is permanently attached to the surface of the recording material carrying the image. It can be used as an image heat fixing device that heats and fixes a fixed image.

Furthermore, it can be used, for example, in a device that heats a recording material carrying an image to modify its surface properties (to make it glossy), and in a device that performs temporary adhesion treatment.

(Background Art) Conventionally, for example, a recording material heating device for heat-fixing an image uses a heating roller maintained at a predetermined temperature and a pressure roller having an elastic layer and in pressure contact with the heating roller. A heated roller system is often used, which heats the recording material while nipping and conveying it.

In addition, various other methods are known, including a flash heating method, an oven heating method, a hot plate heating method, a heald heating method, and a high frequency heating method.

On the other hand, the present applicant has disclosed, for example, in Japanese Unexamined Patent Publication No. 53-313+82, a fixedly supported heating body (hereinafter referred to as a heater), a heat-resistant film that is conveyed (moving and driven) while being in pressure contact with the heater. , has a pressurizing part that brings the recording material into close contact with the heater through the film, and transfers the heat of the heater to the recording material through the film, thereby reducing unfixed particles formed and carried on the surface of the recording material. We have proposed a system and configuration for heat-fixing an image onto the surface of a recording material, and have already put it into practical use.

More specifically, a thin heat-resistant film (or sheet)
a means for moving and driving the film; a heater disposed to fixedly support the film on one side of the film; The film has a pressure member that brings the image-bearing surface of the recording material on which the image is to be fixed into close contact through the image fixing member, and the film is conveyed and introduced between the film and the pressure member at least when image fixing is performed. The recording material is moved in the forward direction at a substantially concave speed and passed through a nip portion as a fixing portion formed by pressing a heater and a pressure member with the traveling film in between. The developer image carrying surface is heated by the heater through the film to impart thermal energy to the developer image (unfixed toner image) to soften and melt it, and then the film and recording material after passing through the fixing section are separated. This is a heating means/device that is basically heated and then separated.

This kind of film heating type equipment uses a heating element with a fast temperature rise and a thin film, which makes it possible to shorten wait time (quick start) and solve various other shortcomings of conventional equipment. It has several advantages and is effective.

FIG. 13 shows a schematic configuration of an example of this type of image heat fixing device using an endless film as the heat-resistant film.

Reference numeral 51 denotes an endless heald heat-resistant film (hereinafter referred to as a fixing film or film), which is arranged below a driving roller 52 on the left side, a driven roller 53 on the right side, and between these driving rollers 52 and driven rollers 53. The low heat capacity linear heating body 54 is suspended between the three members 52, 53, and 54 that are parallel to each other.

The fixing film 51 is rotated at a predetermined circumferential speed in a training direction that is different from the clockwise rotational drive of the drive roller 52, that is, the fixing film 51 is moved at a predetermined circumferential speed in the special training direction, which is different from the clockwise rotational drive of the drive roller 52. It is rotated at a circumferential speed approximately equal to the conveying speed (process speed -1<) of the recording material sheet P as a heating material.

Reference numeral 55 denotes a pressure roller as a pressurizing unit, and biasing means (not shown) against the lower surface of the heating body 54 by sandwiching the film portion on the row side of the fixing film 51 in the shape of the en 1 to lesheld. The recording material sheet P is rotated in a forward counterclockwise direction in the conveying direction of the recording material sheet P.

The heating element 54 is a low heat capacity linear heating element whose length is the width direction of the film (to which the force is directed, which intersects the plane movement direction of the film 51), and includes a heater substrate (base material) 56 and an energized heating resistor (heating element). 57, a surface protection layer 58, a thermometer Y-59, etc., and is fixedly supported by being attached to a support body 61 via a heat insulating material 60.

An unfixed toner image Ta conveyed from an image forming section (not shown) is 1-, and a recording material sheet P supported by blood is a kite 62.
The pressure contact portion N between the heating body 54 and the pressure roller 55 is guided by
The unfixed toner enters between the fixing film 51 and the pressure roller 55 and comes into close contact with the unfixed toner image surface or the lower surface of the fixing film 51 which is being rotated in the same direction at the same speed as the conveyance speed of the recording material sheet P. The film passes between the mutual pressure contact portion N between the heating body 54 and the pressure roller 55 in an overlapping state together with the film.

The heating element 54 is heated with electricity at a predetermined timing, and the thermal energy on the heating element 54 side is transmitted to the recording material sheet 2 side that is in close contact with the film via the film 51, and the toner image Ta passes through the pressure contact part N. During this process, it is heated and becomes a softened and melted image Tb.

The rotating direction of the fixing film 51 is changed at a sharp angle at the edge S of the heat insulating material 60 where the curvature is large. Therefore, the recording material sheet P conveyed through the pressure contact part N while overlapping with the fixing film 51 is at the edge part S.
At this point, the sheet is separated by curvature from the fixing film 51 and is discharged. By the time it reaches the paper discharge section, the tree is cooled and solidified for 1 minute and is completely fixed to the recording material sheet P (Tc).

(Problems to be Solved by the Invention) The following problems are listed as problems with such a film heating type device.

In other words, in the case of a configuration in which a rotary body presses the film against the heating body and drives the film to move, - the maximum width F of the recording material that can be introduced into the apparatus and used, - the direction perpendicular to the direction of film movement The film width dimension is C1 ・The circumferential speed of the rotating body is V10l ・The film is introduced between the film and the rotating body in the nip formed by the heating body and the rotating body with the film in between, and When the circumferential speed of the paper discharge rotary body that relays and discharges and conveys the recording material that has passed through the nip section in a heavy state is V34, the relationship between F and C is F<C or this F<
Condition F: If V10≦V34, the part of the heating material that is being conveyed across the nip and the N1 paper rotating body is used for paper ejection. pulled by a rotating body.

At this time, the film whose surface is coated with a coach ink such as PTFE having good mold releasability is being conveyed at the same speed as the rotating body in the nip portion. On the other hand, the recording material, which is the material to be heated, is conveyed at a speed faster than the circumferential speed of the rotary body in the nip portion, because in addition to the conveyance force by the rotary body, a tensile conveyance force is also applied by the paper discharge rotary body. In other words, the recording material and film slip at the nip, and as a result, as the recording material passes through the nip, unfixed toner images or softened/melted toner images on the recording material are disturbed. There is a possibility that it may cause

The present invention also belongs to the film heating method using an endless heat-resistant film, and the above-mentioned problems have been solved, and this type of heating has various other advantages. The purpose is to provide equipment.

(Means for Solving the Problems) The present invention provides a fixed heating body, an endless heat-resistant film whose inner surface is pressed against the heating body and is driven to move, and the film between the heating body and the heating body. a pressurizing rotary body that presses a recording moon supporting a microscope image to the heating body through the film, which is introduced between the nip part and the outer surface of the film in the nip part; The pressurizing rotary body is in pressure contact with the heating body with the film sandwiched therebetween, and is rotationally driven by a drive source to move the inner surface of the film onto the surface of the heating body while driving the film to move at a predetermined speed in the direction in which the material to be heated is conveyed. The circumferential speed of this rotary body is Vlo, and the circumferential speed of the paper discharge rotary body that relays and discharges the recording material that has passed through the nip portion is VB2.
This heating device is characterized in that V10>VB2.

(Function) (1) When the film is driven and the heating body generates heat, a nip is formed between the heating body and the pressure rotating body with the film sandwiched between the film and the rotating body. When the recording material is introduced with the image-bearing surface facing the film, the recording material comes into close contact with the outer surface of the film and moves through the nip section together with the film, and in the process of moving and passing, it comes into contact with the inner surface of the film at the nip section. The thermal energy of the heating body is applied to the recording material via the film, and the recording material supporting the visible image is heat-treated using a film heating method.

(2) The member that presses the film against the heating body is rotated by a drive source while holding the film in pressure contact with the heating body, and slides the inner surface of the film against the surface of the heating body while moving the film at a predetermined speed in the direction of the recording material conveyance force. By using a rotating body (a roller body or an endless belt body that has both the functions of pressing and driving the film) to move the film, it is possible to reduce the shifting force applied to the film, and also to adjust the position of the rotating body. The positional accuracy of the gear for driving the rotating body can be improved, the device configuration can be simplified, the device can be made inexpensive and highly reliable, and the total circumference of the endless film used can be reduced. It can be made shorter.

(3) As mentioned above, the circumferential speed V10 of the rotating body in the nip part
By setting the circumferential speed V34 of the paper rotating body in the relationship V10>VB2, the conveyance force of the rotating body in the nip part is applied so that the tensile force of the paper ejection rotating body acts on the recording material and the film. Since only a small amount of light is applied, it is possible to prevent slippage between the recording material and the film and to prevent image holes from falling.

(Embodiment) The drawing shows an embodiment of the present invention (image heat fixing device 100).
).

(1) Overall schematic structure of the device 100 FIG. 1 is a cross-sectional view of the device 100, FIG. 2 is a vertical cross-sectional view,
Figures fJ3 and 4 are right and left side views of the device, and Figure 5 is an exploded perspective view of the main parts.

Reference numeral 1 indicates a horizontally elongated device frame (bottom plate) made of sheet metal and has an upward channel (groove) cross section; 2 and 3 indicate a left side wall plate and a right side wall provided on the frame 1 at both left and right ends of the device frame 1; Plate 4 is the upper cover of the device, and left and right side wall plates 2
・It is fitted between the upper ends of 3 and fixed by screwing the left and right ends to the left and right side wall plates 2 and 3, respectively. It can be removed by loosening and removing the screw 5.

6 and 7 are vertical notched elongated holes formed symmetrically in the approximately central portions of the left and right side wall plates 2 and 3, and 8 and 9 are elongated holes 6 and 7, respectively.
These are a pair of left and right bearing members that are fitted into the lower end of the bearing member.

Reference numeral 10 designates a film pressure roller (pressure contact roller, backup roller) as a rotary body that forms a nip portion between the film and a heating body that will be described later and drives the film. The left and right ends of the center shaft 11 are connected to the left and right bearing members 8, respectively.
・9 is supported by a bearing so that it can rotate freely.

Reference numeral 13 denotes a horizontally elongated stay made of sheet metal, which serves as an inner kite member of the film 21 to be described later, and a supporting/reinforcing member for the heating body 19 and the heat insulating member 20 to be described later.

This stay 13 consists of a horizontally long flat bottom part 14, and a wall plate 15 and a rear wall plate 1 having outwardly curved cross-sectional arcs that are raised up from both longitudinal sides of the bottom part 14 in series.
6, and a pair of left and right horizontally projecting lug portions 17 and 18 that project outward from both left and right ends of the bottom surface portion 14, respectively.

Reference numeral 19 denotes a horizontally long low heat capacity linear heating body having a structure (Fig. 6) to be described later.
The heat insulating member 2o is integrally attached and supported in parallel to the lower surface of the horizontally long bottom surface portion 14 of the stay 13 with the heating body 19 side facing downward.

21 is a heat-resistant film made of en-I-less;
9. Stay including heat insulating member 20] Fits externally onto 3.

The inner circumference of the endless heat-resistant film 21 and the outer circumference of the stay 13 including the heating element 19 and the heat insulating part 20 are larger than that of the film 21 by, for example, 3 mm. - It is fitted loosely to the stay 13 including the heat insulating part 20 with a circumferential length or margin.

22 and 23 connect the film 21 to the heating body 19 and heat insulating member 20
These are a pair of left and right film end regulating flange members that are fitted onto the stay 13 containing the stay 13 and then fitted onto and supported by the horizontally projecting lug portions 17 and 18 at the left and right ends of the stay 13. As mentioned later, this left! The distance G between the inner surfaces 22a and 23a of the pair of flange members 22 and 23 (FIG. 8) is set to be slightly larger than the width C of the film 21 (FIG. 8).

24 and 25 are the pair of left and right flange members 22 and 23.
This is a horizontally extending lug portion that protrudes outward from the outer surface of the stay 13 side.
The left and right flange members 22 and 18 are fully fitted into insertion holes provided within the wall thickness of the horizontally extending lug portions 24 and 25 of the flange members 22 and 23, respectively.
I firmly support 23.

To assemble the device, remove the cover 4 from between the left and right side wall plates 2 and 3, and attach the film pressure roller 10 with the left and right bearing members 8 and 9 fitted in advance to the left and right ends of the shaft 11.
Fit and engage the left and right bearing members 8 and 9 into the vertical notched elongated holes 6 and 7 of the left and right side wall plates 2 and 3 from the open upper end, and insert the pressure roller 10 between the left and right side wall plates 2 and 3. , raise the receiver to the position where it can be stopped at the lower end of the left and right bearing members 8 and 9 or the elongated holes 6 and 7 (drop-in type).

Next, the intermediate assembly in which the stay 13, the heating element 19, the heat insulating member 20, the film 21, and the left f=- flange members 22 and 23 are assembled in advance in the relationship as shown in the figure is attached to the heating element 19.
With the sides facing downward, the left and right outward protruding ends of the heat insulating member 20 and the horizontally projecting lug parts 24 and 25 of the left and right flange members 22 and 23 are inserted into the vertically cut long holes 6 and 6 of the left and right side wall plates 2 and 3, respectively. 7 from the open upper end portion, and connect the left and right side wall plates 2.
3 and lower it until the downward heating element 19 hits the upper surface of the previously assembled pressure roller 10 with the film 21 in between and the receiver is stopped (drop-in type).

Then, coil springs 26 and 27 are attached to the lug portions 24 and 25 of the left and right flange members 22 and 23, respectively, which protrude through the elongated holes 6 and 7 to the outside of the left and right side wall plates 2 and 3.
Position the cella 1 vertically using the support protrusions provided on two sides.
- Then, the upper cover 4 is arranged so that the outwardly protruding lug parts 28 and 29 provided on the left and right end sides of the upper cover 4 respectively correspond to the upper ends of the coil springs 26 and 27 set above, respectively, so that the coil springs 26 and 29 are connected to each other. 27 between the lug parts 24, 28, 25, and 29, and then fit it into the specified position between the ends of the left and right side wall plates 2 and 3. Fixed to.

As a result, the stay 13, heating element 19, heat insulating member 20, film 21,
The entire left and right flange members 22 and 23 are pressed downward, and the heating body 19 and the pressure roller 10 or the film 21 are sandwiched between each longitudinal part thereof, and the longitudinal parts thereof are pressed almost equally with a total contact pressure of 4 to 7 kg, for example. is maintained.

Reference numerals 30 and 31 designate power supply connectors for supplying power to the heating weight 9, which are fitted to both left and right ends of the heat insulating portion 20 that protrudes from the outside of the left and right side wall plates 2 and 3 through long holes 6 and 7, respectively.

Reference numeral 32 denotes a heated material artificial kite installed on the front wall of the apparatus frame 1, and a recording material supporting a visible image (powder toner image) Ta as a heated shrine introduced into the apparatus. A sheet P (FIG. 7) is guided toward a nip portion (heat fixing portion) N between the heating body 19 and the pressure roller 10, which are in pressure contact with each other with the film 21 interposed therebetween, between the film 21 and the roller 10.

Reference numeral 33 denotes a heated material exit guide (separation guide) installed on the rear wall of the apparatus frame 1, and the recording material sheet that has passed through the nip is separated from the lower ejection roller 34. It is guided to the nip portion with the pinch roller 38 on the side.

The discharge roller 34 has both left and right ends of its shaft 35 rotatably supported between bearings 36 and 37 provided on the left and right side wall plates 2 and 3. The hook portion 4 of the hook 38 is formed by bending a portion of the rear wall of the upper cover 4 inward.
The receiver is placed in the position 0 and is brought into contact with the upper surface of the discharge roller 34 by its own weight and the push spring 41. This Donjikoro 38
is rotated by the rotational drive of the discharge roller 34.

G1 is a roller shaft 11 that projects outward from the right side wall plate 3.
The first Kia stuck to the right end of the G3 is also the right side wall plate 3
There is a third gear fixed to the right end of the ejection roller shaft 35 projecting outward from G2, and a second gear as a relay gear provided pivotally on the outer surface of the right side wall plate 3. G1
and the third gear G3.

The first gear G1 receives a driving force from a driving gear GO of a drive source mechanism (not shown), and the pressure roller 10 is rotationally driven in the counterclockwise direction in FIG. This is transmitted to the third gear G3 via the second gear G2, and the discharge roller 34 is also rotationally driven in the counterclockwise direction in FIG.

(2) The heat-resistant film 21 of the operation engines 1 to 21 is sandwiched between the nip N between the heating body 19 and the pressure roller 10 when not driven, as shown in the enlarged view of the main part in FIG. Most of the remaining portion, excluding the entire circumference, is tension-free (a state in which no tension is applied).

When the drive is transmitted from the drive gear GO of the drive source mechanism to the first KIA G1 and the pressure roller 10 is driven to rotate in the direction 31 counterclockwise to the seventh roller at a predetermined circumferential speed, the film 21 rotates at the nip portion N. A feeding movement force is applied due to the frictional force with the pressure roller 10, and the endless heat-resistant film 21 slides on the inner surface of the film or the surface of the heating element 19 at approximately the same speed as the peripheral rotational speed of the pressure roller 10 while moving in the clockwise direction A. It is driven to rotate and move.

In this driving state of the film 21, a pulling force f acts on a portion of the film upstream of the nip portion N in the film rotation direction, so that the film 21 is moved further than the nip portion N as shown by the solid line in FIG. Contact with the inner surface of the film on the upstream side in the film rotation direction and near the nip, that is, the approximately lower half surface portion of the outwardly curved face plate 15 as the inner surface of the stay 13 on which the film 21 is fitted. Activate your passion and move around.

As a result, the rotating film 21 rotates with tension acting on the film portion B of the force from the starting point O of the contact sliding portion with the front plate 15 to the nip N on the downstream side in the film rotation direction. 214A near the sheet entry side of the nip portion N, and the film portion of the nip portion N by the action of the tension. be done.

Then, while the film is being driven and the heating element 19 is energized, the old recording sheet P carrying the unfixed toner image Ta as the heated month is guided by the artificial kite 32 and rotates around the nip portion N. Dynamic film 21 and pressure roller 10
When the two image bearing surfaces are introduced between the recording material sheet 1 and
- P is in close contact with the surface of the film 21 and moves through the nip part N with the film 21, and in the process of moving and passing, the thermal energy of the heating element 19 that is in contact with the inner surface of the film at the nip part N is absorbed by the film. Recording material sheet P via
(=j), and the toner image Ta becomes a softened and fused image Tb.

The recording material sheet P that has passed through the nip portion N leaves the surface of the film 21 in a state where the toner temperature is higher than the glass transition point and comes out from the II kite 33, is guided between the discharge roller 34 and the pinch roller 38, and is sent out of the apparatus. It will be done. The softened/melted toner image Tb is cooled and fixed as an assimilation image TCL/ while the old recording sheet P exits the nip portion N, leaves the film 21 surface, and reaches the discharge roller 34.

As described above, the recording material sheet P introduced into the nip portion N is under tension and moves in the nip portion N together with the film 21 while always being in close contact with the unwrinkled film surface, thereby eliminating wrinkles. To prevent uneven heating and fixing caused by a certain film passing through the nip portion N, and to prevent creases on the film surface.

The film 21 has a total circumferential length of -2N both when being driven and when being driven.
Or, since tension is applied only to B-N, that is, when not driven (Fig. 6), the film 21 is at the nip portion N.
Almost all of the remaining circumference except for the remaining part is tension-free, and during driving, tension acts only on the nip part N and the film part B near the recording material sheet entrance side of the nip part N, and the remaining part is tension-free. Since almost the entire circumference is tension-free, and a film with a short circumference can be used throughout, the drive torque required to drive the film is small, and the film device configuration, parts, and drive system The configuration is simplified, smaller, and lower in cost.

Also, when the film 21 is not driven (FIG. 6) and when it is driven (FIG. 7),
In Figure 2, tension is applied to the film 21 only at -2N or B-N of the entire circumference as described above, so when the film is driven, the film 21 is placed on one side Q in the film width direction (Figure 2) or on the other side. Even if a shift toward side R occurs, the shift force is small.

Therefore, the film 21 shifts Q or R, and its left edge becomes the inner surface 22a of the film end regulating surface of the left flange member 22, or its right edge becomes the right flange 23.
Even if it comes into contact with the inner surface 23a of the seat, since the film biasing force is small, the rigidity of the film sufficiently overcomes the biasing force, and the ends of the film do not buckle or break. In addition, since the film deviation regulating means is sufficient with the simple flange members 22 and 23 as in the device of this embodiment, the device configuration can be simplified, downsized, and lowered in cost, making it inexpensive and highly reliable. Can configure devices.

In addition to the flange members 22 and 23 in the case of the device of this embodiment, for example, a rib made of heat-resistant resin is provided at the end of the film 21 in the circumferential direction of the endless film as the film deviation regulating means, and this rib is regulated. Good too.

Furthermore, as the film 21 to be used, the rigidity can be reduced to compensate for the reduction in the biasing force as described above, so that the quick start performance of the device can be improved by using a film that is thinner and has a smaller heat capacity.

(3) Regarding film 21.

Film 21 has a smaller heat capacity than Quickstar 1~
In order to improve the properties, the film thickness T of the film 21 is set to a total thickness of 1
A single layer or composite layer film having heat resistance, mold releasability, strength, durability, etc. of 00 μm or less, preferably 40 μm or less, and 20 μm or more can be used.

For example, polyimide polyetherimide (PEI)
・Polyether sulfone (PES) 4-functional ethylene-perfluoroalkyl vinyl ether copolymer resin (P
FA), polyetheretherketone (PEEK), polyparabanic acid (PPA), or a composite layer film such as a 20 μm thick polyimide film with PTFE (tetrafluoroethylene resin) PAF-F on at least the image contact side.
It has a releasable coating layer of 10 μm Jq made by adding a conductive material (carbon black, graphite, conductive whiskers, etc.) to fluororesin such as EP, silicone resin, etc.

(4) Regarding the heating body 19 and heat insulating member 20.

The heating element 19, similar to the heating element 54 of the apparatus shown in FIG. 13, includes a heater substrate 19a (see FIG. 6), an energized heating resistor (heating element) 19b, a surface protection layer 19c, a temperature measuring element 19d, and the like.

The heater board 19a is a heat-resistant, insulative, low heat capacity, and high thermal conductive member, and has a thickness of 1 mm and 11110 m, for example.
It is an alumina substrate with a length of 240 mm.

The heating element 19b is located on the lower surface of the heater board 19a (film 21
For example, Ag
/Pd (silver palladium), Ta2N, RuO2, or other electrically resistive material is coated in the form of a line or strip with a thickness of about 10 μm and a medium size of 1 to 3 mm by screen printing, etc., and heat-resistant glass is applied as a surface protective layer 19c on top of it. It is coated with a thickness of approximately 10 μm. The temperature measuring element 19d is, for example, a low heat capacity measuring element such as a PT film coated by screen printing or the like on the upper surface of the heater substrate 19a (the surface opposite to the surface on which the heating element 19b is provided) approximately in the center. It is a temperature resistor. It can also be used with low heat capacity thermistors.

In the case of the heating element 19 of this example, the heating element 19b having a linear or narrow strip shape is energized at a predetermined timing in response to an image formation start signal to cause the heating element 19b to generate heat over substantially its entire length.

The power supply is AClooV, and the supplied power is controlled by controlling the phase angle of the current supply by a power supply control circuit (not shown) including a triac according to the temperature detected by the temperature measuring element 19c.

When the heating element 19 is energized, the heater substrate 1.9a, the heating element 19b, and the surface protective layer 19c have a small heat capacity, so that the surface of the heating element reaches a required fixing temperature (for example, 1.9
The temperature rises rapidly to 40-200°C.

The heat-resistant film 21 in contact with the heating element 19 also has a small heat capacity, and the thermal energy on the heating element 19 side is transferred to the recording material sheet P in pressure contact with the film through the film 21.
The image is effectively transferred to the side and thermal fixation of the image is performed.

As mentioned above, the surface temperature of the film facing the heating element 19 rises to a high enough temperature relative to the melting point of the toner (or the temperature at which it can be fixed to the recording material sheet P) in a short period of time, resulting in excellent quick start performance. There is no need for so-called standby temperature control in which the temperature of the heating element 19 is raised in advance, so that energy can be saved and temperature rise inside the machine can be prevented.

The heat insulating member 20 insulates the heating element 19 to make effective use of heat generated, and is made of materials that have heat insulating properties and high heat resistance, such as pps (polyphenylene sulfide), P/M (polyamideimide), and PI (polyimide).・PEEK (
Polyetheretherketone), liquid crystal polymer, and other highly heat-resistant resins.

(5) Regarding film width C and nip length.

As shown in the dimensional relationship diagram in FIG. 8, the width of the film 21 is C, and the length of the nip formed by pressing the heating body 19 and the pressure roller 1o as a rotating body with the film 21 in between is D. In this case, it is preferable to set the relationship such that C<D.

That is, when the film 21 is conveyed by the roller 10 with the relationship C20, contrary to the second paragraph, the film conveyance force (pressure contact force) that is applied to the film portion within the nip length region,
The film conveying force that is applied to the film portion outside the nip length region is such that the inner surface of the former film portion is in contact with the heating body 19 and is conveyed by sliding motion, whereas the inner surface of the latter film portion is conveyed by the heating body 19. Insulating member 2 whose material is different from the surface of
Since the film is transported slidingly in contact with the surface of the film 210, there is a risk that damage such as wrinkles or folds may occur at both ends of the film 210 in the width direction during the film transport process.

On the other hand, by setting the relational structure of C<D, the film 210 is conveyed by sliding on the surface of the heating body in contact with the inner surface of the entire length region C in the width direction or the surface within the length range of the heating body 19. As a result, the film conveyance force is made uniform in the entire length region C in the film width direction, so that the above-mentioned film edge damage draught can be avoided.

Further, since the pressure roller 10 used as a rotary body in this embodiment is made of a com abrasive material such as silicone rubber which has excellent elasticity +1, the friction coefficient of the surface changes when heated. Therefore, the length range dimension of the heating element 19b of the heating element 19 is E.
When, the coefficient of friction between the roller 10 and the film 21 at a portion corresponding to the length range E of the heating element 19b, and the friction coefficient between the roller 10 and the film 21 at a portion corresponding to the outside of the length range E of the heating element 19b. The friction coefficient of is long.

However, by setting the dimensional relationship configuration of E<C<D, it is possible to reduce the difference between the length range E of the heating element 19b and the film width C. The difference in the coefficient of friction between the roller 10 and the film 21 can reduce the influence on film conveyance.

This makes it possible to stably drive the film 21 with the roller 10, making it possible to prevent the edges of the film from being damaged.

Flange members 22 and 23 as film end regulating means
The film end regulating surfaces 22a and 23a of the pressure roller 10
The length is within the range of , and even if the film shifts, the edges of the film are prevented from being tampered with.

(6) Regarding the pressure roller 10.

The pressure roller 10, which forms a nip N by sandwiching the film 21 between it and the heating body 19, and serves as a rotating body for driving the film, is made of a rubber elastic body with good mold release properties, such as silicone rubber, for example. 9 (A) or (
It may have an inverted crown shape as shown in the exaggerated model diagram of B), or a substantially inverted crown shape in which the end portion of the inverted crown is cut 12a.

The degree d of the inverted crown is preferably set to d=100 to 200 μm when the effective length H of the roller 10 is, for example, 230 mm.

That is, in the case of a straight shape, due to variations in component precision, etc., the pressure distribution in the film width direction applied to the film 21 by the roller at the nip N with the heating element 19 will be smaller in the center than in the widthwise ends of the film. Sometimes it was higher. In other words, the conveying force of the film by the roller is greater at the center than at the ends in the width direction of the film, and as the film 21 is conveyed, a force is applied to the film 21 that tends toward the portion of the film where the conveying force is small or the portion where the conveying force is large. Therefore, wrinkles may occur in the film as it approaches the edges of the film or the center of the film.
Furthermore, when the recording material sheet P is introduced into the recording material sheet 1 into the nip portion N, the recording material sheet P may be wrinkled during the conveyance process through the nip portion.

On the other hand, by making the pressure roller 10 have an inverted crown shape, the pressure distribution in the film width direction applied by the roller to the film 21 at the nip N with the heating element 19 is opposite to the above case. The edges in the width direction are larger than the center, and as a result, a force acts on the film 21 from the center toward both ends, that is, the film 21 is transported without being subjected to the wrinkle smoothing action.
It is possible to prevent wrinkles on the film and also to prevent wrinkles on the introduced recording material sheet P.

The pressure roller 10 as a rotating body, as in the device of this embodiment, sandwiches the film 21 between it and the heating body 19 to bring the film 21 into sweat contact with the heating body 19, and drives the film 21 to move at a predetermined speed. When a recording material sheet P as a heated material is introduced between the film 21 and the film 21, the recording material sheets 1 to P are brought into close contact with the surface of the film 21, pressed against the heating body 19, and moved together with the film 21 at a predetermined speed. By using a driving member to be driven, it is possible to reduce the shifting force applied to the film, and it is also possible to match the position of the roller 10 and the positional granularity of the chias for driving the roller.

That is, the film 21 or the film 2
1 and the recording material sheet P, and a drive function to move and drive the film 21, are provided by separate pressurizing rotary bodies (the necessary pressurizing force is obtained by pressurizing these rotary bodies). If the heating element 19 and the film drive function are performed by a rotary body, if the alignment between the heating body 19 and the film drive function rotor goes out of alignment, the thin film 21 will be subjected to a large biasing force in the width direction. As a result, the edges of the film 21 may be bent, wrinkled, or otherwise damaged.

In addition, a heating body 1 is attached to the pressurizing rotary body that also serves as a film drive member.
When applying the pressure necessary for pressure contact with 9 by a pusher such as a spring, the position of the rotating body and the positional granularity of the gear for driving the rotating body are appropriate.

On the other hand, as described above, a pressure necessary for fixing is applied to the heating body 19, and the pressure roller 10, which is a rotary body, presses the recording material sheet 1-P through the film 21, and also presses the recording material sheet 1-P with the recording material sheet P. By driving the film 21 at the same time, the above-mentioned effects can be obtained, and the structure of the device can be simplified, making it possible to obtain an inexpensive and highly reliable device.

Note that instead of the roller 10, the rotating body may be an endless heald 10A that is rotationally driven as shown in FIG.

The configuration in which the rotary bodies 10 and 10A have the function of pressing the film 21 against the heating body 19 and the function of driving the film 21 is suitable for a film tension-free type device (at least part of the film 21) like the device of this embodiment. is a device in which no tension is applied both when the film is not being driven and when the film is being driven), a film tension type device (such as the device shown in Fig. 13 above, which always applies tension all the way around a long film) There are also film deviation control means, sensor/solenoid method, rib control method, film edge control method (
Although the same action and effect can be obtained by applying the present invention to either the two-sided or one-sided regulation method, it is particularly suitable for application to a tension-free type device configuration.

(7) Regarding recording material sheet ejection speed.

Recording material sheet 1 as a heated material introduced into the nip portion N
- The conveyance speed by the pressure roller 10 (rotating body) of P, that is, the circumferential speed of the feed roller 10, is V10, and the conveyance speed of the recording material sheet tj of the jJ1 output roller 34, that is, the circumferential speed of the discharge roller 34, is VB2. If so, should the speed relationship be set to V10>VB2? The speed difference may be set to several percentages, for example, about 1 to 3%.

When F is the maximum width of the recording material sheet P that can be introduced into the apparatus and used (see FIG. 8), in relation to the width C of the film 21, under the condition of F<C, vio≦V3.
4, the recording material sheet 1 is being transported between the nip portion N and the discharge roller 34.
~P indicates that the sheet portion passing through the nip portion N is discharge roller 3.
Pulled by 4.

At this time, the film 21 whose surface is coated with PTFE or the like having good mold releasability is being conveyed at the same speed as the pressure roller 10.

The recording material sheet P is conveyed at a speed faster than the circumferential speed of the pressure roller 10 because, in addition to the conveyance force by the pressure roller 1o, a tensile conveyance force by the NU output roller 34 is also applied.

Recording material sheet P and film 2 at tight nip portion N
1 is in a state of slipping, and therefore the recording material sheet P is passing through the nip part N, and the recording sheet P-
There is a possibility that the undetermined valley toner image Ta (FIG. 7) of L or the toner image Tb that has been softened and melted is disturbed.

Therefore, as described above, by setting the circumferential velocity V10 of the pressure roller 10 and the circumferential velocity V34 of the output roller 34 in the relationship of V10>VB2, the relationship between the recording material sheet P and the film 2
1, since only the conveying force of the pressure roller 10 is applied to the sheet P without the tensile force of the discharge roller 34 acting on the sheet P.
Due to the slippage between the sheet P and the film 21, it is possible to prevent the occurrence of image blurring as described in (2) above.

In this embodiment, the output roller 34 may be provided on the side of the heating device 100, or may be provided on the side of the main unit, such as an image forming apparatus into which the heating device 100 is incorporated.

(8) Regarding the film edge regulation flange spacing.

The inner surface 22 of the pair of left and right flange members 22 and 23 serving as the first stage of film edge regulation serves as a film edge regulation surface.
When the distance between a and 23a is G (FIG. 8), the relationship with the width C of the film 21 may be set such that C<G. For example, when C is set to 230 mm, G is set approximately 1 to 3 mm larger.

That is, the film 21 has a thickness of, for example, 200 at the nip portion N.
It expands upon receiving the heat from the heating element 19, which is close to 0.degree. C., and increases in temperature. Therefore, if the width dimension C of the film 21 and the flange interval dimension G at room temperature are set to C=G, and both ends of the film 21 are regulated by the flange members 22 and 23, when the device is in operation, the Thermal expansion creates a state where C>G. The film 21 has a thickness of 50 μm, for example.
Since it is a thin film of about
The contact pressure (end pressure) at the film end against 3a increases, and before it can withstand the pressure, the end is bent, buckled, etc., and due to the increase in the film end pressure, the end of the film 21 Since the frictional force between the film end regulating surfaces 22a and 23a of the flange members 22 and 23 also increases, the film conveyance force also decreases.

By setting the dimensional relationship C<G, even if the film 21 expands due to heating, the gap (G-C
) is provided between both ends of the film 21 and the film end regulating surfaces 22a and 23a of the flange member, thereby preventing both ends of the film 21 from coming into contact with the film end regulating surfaces 22a and 23a of the flange member at the same time.

Therefore, even if the film 21 expands thermally, the film end pressure contact force does not increase, which prevents the end of the film 21 from being damaged.
At the same time, the film driving force can be reduced.

(9) Regarding the friction coefficient relationship between external materials.

a, roller (rotating body) 1 against the outer peripheral surface of the film 21
0 surface friction coefficient μm, b, friction coefficient of the heating body 19 surface against the inner peripheral surface of the film 21 μ2, C3 friction coefficient of the roller 10 surface against the heating body 19 surface μ3, d, record as heated material The friction coefficient of the outer peripheral surface of the film 21 with respect to the surfaces of the recording material sheets 1 to P is μ4, e The friction coefficient of the surface of the roller 10 with respect to the recording material sheet 82 surface mi is μ5, f, the conveyance direction of the recording material sheet P introduced into the apparatus If the maximum length is 1, and it is incorporated into a transfer type image forming apparatus as a G8 device or an image heat fixing device, record from the image transfer means part to the nip part N of the device as an image heat fixing device. The conveyance path length of the material sheet (transfer material) P is assumed to be 12.

Therefore, the relationship between μm and μ2 is μm〉μ2 The relationship structure is as follows.

That is, in this type of film heating type device, the relationship between μ4 and μ5 is set as μ4<μ5, and in the image forming apparatus, the relationship is 11! The relationship with 2 is fi+ > 12
It becomes.

At this time, if μm≦μ2, the film 21 and the recording material sheet P slip in the cross-sectional direction of the heat fixing means (the transport speed of the film 21 lags behind the circumferential speed of the roller 10).
The toner image on the recording material sheet 1 is disturbed during heat fixing.

In addition, if the recording material sheet P and the film 21 slip together (the transport speed of the film 21 and the recording material sheet P is delayed relative to the peripheral speed of the roller 10), in the case of a transfer type image forming apparatus, the image transfer When the toner image is transferred onto the recording material sheet (transfer material) in the means section, the toner image on the recording material is also disturbed.

- By setting μm>μ2 as shown in , the film 21 and the recording material sheet P relative to the roller 10 in the cross-sectional direction
Can prevent slipping.

Furthermore, regarding the width dimension C of the film 21, the length dimension H of the roller 10 as a rotating body, and the length dimension of the heating body 19, under the conditions that C<H and C<D, the relationship configuration is μm>μ3. Make it.

That is, if μm≦μ3, in the width direction of the heat fixing means,
The film 21 and the roller 10 slip, and as a result, the film 21 and the recording material sheet P slip, and the toner image on the recording material sheet is disturbed during heat fixing.

By establishing the relationship μm>μ3 as described above, it is possible to prevent the film 21 from slipping against the roller 10 in the width direction, particularly on the outside of the recording sheet P.

By setting μm>μ2 and μm>μ3 in this way,
The conveying speed of the film 21 and the recording material sheet P can always be made the same as the peripheral speed of the roller 10, which can prevent image disturbance during fixing or transfer, and μm>μ.
2. By performing μm>μ3 at the same time, roller 1
It becomes possible to always make the circumferential speed (=process speed) of 0 and the transport speed of the film 21 and the recording material sheet P the same, and in the transfer type image forming apparatus, (10) film deviation control.

The film shift control of the embodiment apparatus shown in FIGS. 1 to 10 is performed by disposing a pair of left and right flange members 22 and 23 on both ends of the film 21 in the width direction for controlling the ends of the film. This is to cope with the deviation movement QR of the film (film both-side edge regulation type), but the following configuration is also effective as a film one-side edge regulation type.

In other words, the driving side of the left and right pressure coil springs 26 and 27 is set so that the direction in which the film is shifted in the width direction is always either leftward Q or rightward R. By setting the pressing force f27 of the spring 27 to be higher than the pressing force f26 of the spring 26 on the non-driving side (f27>f26), the film 21 is always moved toward the driving side I side R. In addition, the shape of the heating element 19 and the shape of the roller 10 can be changed between the driving end side and the non-driving end side to control the film conveying force so that the film always moves in one direction. The end of the film on the closer side is regulated by means such as a flange member as a regulating member for the end of the film on that side, a film rib and an engagement guide member, etc. In other words, in the apparatus shown in FIG. By regulating only the edge of the film 21 on the side R using the regulating member 27, it becomes possible to stably and easily control the film deviation. As a result, when the apparatus is an image heat fixing apparatus, a stable and good fixed image can always be obtained.

Further, since the endless film 21 is driven by the roller 10 forming the nip portion N, no special driving roller is required.

Similar effects can be obtained both in the case of a tension-type device configuration in which the film is driven by applying tension all around it, and in the case of a tension-free type device configuration like the device of this embodiment. However, the means structure is particularly suitable for tension-free types.

(11) Example of Image Forming Apparatus FIG. 12 shows a schematic configuration of an example of an image forming apparatus incorporating the image heat fixing apparatus 100 shown in FIGS. 1 to 10.

The image forming apparatus of this example is a laser beam printer using a transfer type electrophotographic process.

60 is a process cartridge, which includes a rotating drum type electrophotographic photoreceptor (hereinafter referred to as drum) 61 and a charger 62
- It includes four process devices: a developing device 63 and a cleaning device 64. This process cartridge can be attached to and removed from a predetermined position within the apparatus by opening the opening/closing part 65 of the apparatus and opening the inside of the apparatus.

The tram 61 is driven to rotate in the clockwise direction of the arrow by the image forming start signal, and the surface of the rotating drum 61 or the charger 62 is rotated.
The charged surface of the drum is charged to a predetermined polarity and potential by a laser beam 67 modulated in accordance with a time-series electric digital pixel signal of the target image information output from a laser scanner 66. By performing main scanning exposure, an electrostatic latent image corresponding to target image information is sequentially formed on the surface of the drum 61. The latent image is then developed into a toner image by a developing device 63.

On the other hand, the recording material sheets P in the paper feed cassette 68 are separated and fed one by one by the cooperation of the paper feed roller 69 and the separation roller l<70, and are synchronized with the rotation of the tram 61 by the lettuce 1 roller pair 71. Then, the drum 61 is fed to a pressure nip 73 which is a fixing part between the drum 61 and a transfer roller 72 which is in pressure contact with the drum 61, and images 1 to 2 on the side of the drum 1 are sequentially transferred onto one surface of the fed recording material sheet. η: Being done.

The recording material sheet P that has passed through the transfer section 73 is separated from the tram 61 and introduced into the fixing device 100 via a kite 74.
The unfixed toner image is heat-fixed by the operation and action of the device 100 which has moved at high speed, and is outputted as an image-formed product (print) from output 175.

The surface of the drum 61 from which the recording material sheet P has been separated through the transfer section 73 is subjected to removal of transferred dyes such as untransferred materials 1 to 2, and is repeatedly used for image formation.

The heating device of the present invention is not only suitable as an image heating and fixing device for the image forming apparatus described above, but also can be effectively used as an image surface heating and polishing device and a temporary fixing device.

(Effects of the Invention) As described above, the film heating type heating device of the present invention simplifies the configuration of the device and reduces costs by pressing and moving the film against the heating body using the pressure rotating body. It becomes possible.

Further, by setting the relationship between the circumferential speed V10 of the pressure rotating body in the nip portion and the circumferential speed V34 of the paper rotating body as V10>VB2, the recording material and the film are Since only the conveyance force is reduced, it is possible to prevent slippage between the recording material and the film, and it is possible to always obtain clean heat-treated images.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an embodiment of the device. Figure 2 is a longitudinal sectional view. Figure 3 is a right side view. Figure 4 is a left side view. FIG. 5 is an exploded perspective view of the main parts. FIG. 6 is an enlarged cross-sectional view of the main part showing the state of the film when not driven. FIG. 7 is the same diagram as above when driving. FIG. 8 is a dimensional relationship diagram of the constituent members. FIGS. 9(A) and 9(B) each show a roller 10 as a rotating body.
An exaggerated shape diagram showing an example of the shape. FIG. 10 is a diagram showing an example in which a rotating heel is used as a rotating body. FIG. 11 is a longitudinal cross-sectional view of an example of a device that regulates one end of the film. FIG. 12 is a schematic configuration diagram of an example of an image forming apparatus. FIG. 13 is a schematic diagram of a known example of a film heating type image heating fixing device. 9 is a heating body, 1 is an endless film, 3 is a stay 0 is a roller as a rotating body.

Claims (1)

[Claims] (1) A fixed heating body, an endless heat-resistant film whose inner surface is pressed against the heating body and is driven to move, and the film is sandwiched between the heating body to form a nip portion, and the nip portion is formed by sandwiching the film between the heating body and the heating body. a pressurizing rotary body which is introduced between the outer surface of the film in the section and presses the recording material supporting the microscope image onto the heating body through the film, the pressurizing rotary body sandwiching the film between the recording material and the heating body; It is a rotating body that is in pressure contact with the heating body and is rotationally driven by a drive source to move the film at a predetermined speed in the direction of conveyance of the heated material while sliding the inner surface of the film on the surface of the heating body. A heating device characterized in that V10>V34, where V10 is V10, and V34 is the circumferential speed of a paper discharge rotary body that relays and discharges the recording material that has passed through the nip portion.