JPH11135231A - Heating device, fixing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a guide member from deforming to the opposite side of the surface of a heated material transportation road and to prevent thermal deformation from causing paper jam, by providing a guide member with a projection touching a cover member at a given position. SOLUTION: An upper guide 612' is placed between side plates of a frame 616 and is positioned by engaging a longitudinally provided boss into a positioning hole of the frame 616. A projection 612'e is provided in the longitudinal center of the upper guide 612' so as to bring into contact with an upper cover 611. Thus, even if the upper guide 612' intends to deform in the direction opposite to a heated material transportation road due to heat from a heating means 601, the projection 612'e touches the upper cover 611 and is pressed by it to avoid deformation. Therefore, pressure contact to a transporting roller 603b of a roller 603a provided for the upper guide 612' is also appropriately maintained, and paper jam, jam of heated material P is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating device or a fixing device for heating a material to be heated at a heating nip where a heating means and a pressing member are pressed against each other, and an electrophotographic process provided with the heating device or the fixing device. The present invention relates to an image forming apparatus such as a copying machine and a printer using the same.

[0002]

2. Description of the Related Art Conventionally, a heating roller system has been widely used as a heating device in an image forming apparatus such as a copying machine or a printer. In this method, a recording material is fixed to a press nip (fixing nip) between a heating roller (fixing roller) maintained at a predetermined heating temperature by a built-in heat source such as a halogen heater and an elastic pressing roller pressed against the heating roller. And heats and fixes an unfixed image on the surface of the recording material by the heat of the heating roller.

Recently, a heating apparatus of a film heating type has been proposed and put into practical use. This heating device
A method and configuration in which the material to be heated is brought into close contact with the heating body via a heat-resistant film, the heating body and the heat-resistant film are relatively moved, and the heat of the heating body is applied to the material to be heated through the heat-resistant film. The image can be utilized as a means for heat-fixing the image as a permanent fixed image on the surface of the recording material carrying the toner image.

FIG. 8 is a schematic cross-sectional view of a principal part of such a film heating type heating device.

Reference numeral 601 denotes a heat generating means, which is a sheet heater 601a elongated in the direction perpendicular to the paper, a film guide 601c for holding the heater 601a, a stay member 601d for reinforcing the film guide, and a cylinder externally fitted to these. And the like.

Reference numeral 602 denotes a pressure roll member which presses against the heat generating means 601 to form a heating nip N;
Is a transporting means for transporting the material to be heated on the downstream side of the heating nip portion N in the direction of transporting the material to be heated.
b and a driven roller 603a pressed against this.

Thus, the pressure roll member 602 is driven to rotate, and accordingly, the cylindrical fixing film 601b rotates around the film guide 601c, and the heater 601 is rotated.
In the state where the fixing nip N is heated to a predetermined temperature by the heat generation of the recording material P, the recording material P on which the unfixed toner image t is formed by the image forming unit (not shown) is moved to the fixing nip N
Is introduced between the fixing film 601b and the pressure roller 602 with the image surface facing upward, that is, facing the outer surface of the fixing film, and the image surface is sandwiched with the fixing film 601b in close contact with the outer surface of the fixing film 601b. Together, they are transported in the fixing nip N. In the process of being conveyed through the fixing nip N, heat from the heater 601a is applied via the fixing film 601b, and the unfixed toner image t is heated and fixed on the recording material P. The heated material P after passing through the fixing nip is conveyed by the conveying means 603, guided by the upper guide 612 and the flapper 605, and discharged to the stacking portion on the downstream side in the conveying direction.

[0008]

In the conventional example shown in FIG. 8, the upper guide 612 is provided with the heater 60.
In particular, the resin material is used in the above example because it is close to the heat generating means 601 having 1a, so that there is a problem that thermal deformation is likely to occur.

When the thermal deformation occurs, the roller 603a held by the upper guide 612 is not pressed to the first discharge roll 603b at a predetermined pressure, and the conveying force is reduced to reduce paper jam. May occur.

Further, the roller 603a is often made of a fluororesin so that the toner does not adhere thereto. However, since the fluororesin has a poor abrasion resistance, as shown in FIG.
With the configuration in which the shaft of the roller 603a is held by the spring 603d, there is a problem that the rotation of the roller 603a gradually cuts the shaft, and in the worst case, breaks the shaft, causing a paper jam.

Accordingly, an object of the present invention is to provide a heating device, a fixing device, and an image forming apparatus which are provided with a projection for suppressing thermal deformation of a guide member or a roller supporting member, thereby preventing paper jam due to the thermal deformation. I have.

Also, the present invention provides a heating device, a fixing device, and a fixing device in which a shaft portion of a roller and a roller portion are formed as separate members, thereby suppressing abrasion of the shaft portion and preventing paper jam due to breakage of the roller. It is intended to provide an image forming apparatus.

[0013]

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

[1] A heat generating means, a pressing member which is in pressure contact with the heat generating means to form a heating nip portion of the material to be heated, and a pressing member which is located downstream of the heating nip portion in the direction of transport of the material to be heated. In a heating device comprising: a guide member for guiding a heating material; a frame member for holding at least a part of the heat generating means, the pressure member and the guide member; and a cover member fixed to the frame member. A fixing member provided with a projection at a predetermined position to prevent deformation of the guide member on a side opposite to a surface of the material to be transported.

[2]: a heating means, a pressurizing member which presses the heating means mutually to form a heating nip portion of the material to be heated, and a heating member which is located downstream of the heating nip portion in the direction of transport of the heating material. In a heating device, the cover member includes a guide member for guiding a heating material, a frame member for holding at least a part of the heat generating means, the pressure member, and the guide member, and a cover member fixed to the frame member. A fixing member provided with a projection which is located at a predetermined position with respect to the guide member, to prevent the guide member from being deformed on the side opposite to the surface of the material to be transported. [3]: In the heating device according to [1] or [2],
A heating device, wherein the guide member holds rollers of a conveying means for conveying the material to be heated in the downstream direction of the material to be heated [4]: a heating means and a pressure contact between the heating means and the heating means A pressurizing member that forms a heating nip portion of the material to be heated, a conveying unit that conveys the material to be heated downstream of the heating nip in the direction of conveying the material to be heated, and a heating unit, a pressing member, and a conveying unit. In a heating device including a frame member that holds at least a part thereof and a cover member fixed to the frame member, the transporting unit includes a drive roll, a roller pressed against the drive roll, and a support member for the roller. A fixing device, wherein the support member is provided with a projection which is located at a predetermined position with the cover member.

[5]: a heat generating means, a pressing member which is in pressure contact with the heat generating means to form a heating nip portion of the material to be heated, and a material to be heated downstream of the heating nip in the direction of transport of the material to be heated. And a frame member that holds at least a part of the heating unit, the pressure member, and the transportation unit, and a cover member that is fixed to the frame member, wherein the transportation unit is driven. A heating device, comprising: a roll, a roller pressed against the driving roll, and a support member for the roller, wherein the cover member is provided with a projection that is located at a predetermined position with the support member.

[6] The heating device according to [4], wherein the protrusion is provided in a direction opposite to a direction in which the roller is pressed against the drive roll.

[7] The heating device according to [5], wherein the protrusion is provided in the same direction as the direction in which the roller is pressed against the drive roll.

[8]: The support member is a guide member for guiding the material to be heated downstream of the heating nip in the direction of transport of the material to be heated [4],
The heating device according to [5], [6] or [7].

[0020]

[9]: a heat generating means, a pressing member which presses the heat generating means with each other to form a heating nip portion of the material to be heated, and a heating material at a downstream side of the heating nip portion in the direction of transport of the material to be heated. A guide member for guiding, a transporting unit including a transport roll and a roller for transporting the heated material from the heating nip portion to the downstream side in the transport direction of the heated material, and a spring member for urging the roller member toward the transport roll. A heating device according to claim 1, wherein said roller comprises a non-rotatable shaft member and a rotatable roller portion.

[10]: a heating means, a pressurizing member which forms a heating nip portion of the member to be heated by being pressed against the heating means, and a conveying means for conveying the material to be heated passing through the heating nip In the heating device having:
A heating device comprising: a driving roll; and a roller pressed against the driving roll, wherein the heating device is configured using a shaft member that cannot rotate the roller and a rotatable roller portion.

[11]:

The heating device according to [9] or [10], wherein the shaft member is made of a metal material, and the roller portion is made of a fluororesin.

[12]:

[9], [10] or [11]
Wherein the roller portion is urged against the drive roll by a spring member, and at least one end of the shaft member is pressed into and held by a shaft holding portion of the spring member. Heating equipment.

[13]: In the heating device of [12],
A heating device, wherein the shaft member holding portion of the spring member has a ring shape.

[14] A fixing device comprising the heating device according to any one of [1] to [13] as means for heating and fixing an image formed on a recording material. .

[15]: an image forming means for forming an image on a recording material, and an image heating device for heating the image formed on the recording material by the image forming means; An image forming apparatus comprising the heating device according to any one of [1] to [13].

(Action) The guide member may be provided with a protrusion at a predetermined position with the cover member, or the cover member may be provided with a protrusion at a predetermined position with the guide member, so that the guide member is provided on a side opposite to the heated material transport path. Is prevented from being deformed, and jamming (paper jam) of the member to be heated due to the deformation is prevented. In particular, when the guide is provided with a roller of the conveying means, by suppressing the deformation, the pressing force of the roller can be maintained, and paper jam due to insufficient conveying force can be prevented.

[0028] By forming the roller with a shaft portion and a rotatable roller portion, the material of the shaft portion can be freely selected irrespective of the material of the roller portion. For example, a fluororesin having a good toner release property as the roller portion In the case where is used, by selecting a metal or the like having sufficient abrasion resistance as the shaft portion, there is no fear that the shaft portion is broken and paper jam can be prevented.

Further, the shaft is press-fitted and held in at least one of the ring-shaped portions of the spring member, thereby preventing the shaft from coming off the roller portion and the spring member during assembly, and Improving sex.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 is a schematic cross-sectional view of the apparatus of the present embodiment,
FIG. 2 is a side view of the apparatus, and FIG. 3 is a view showing X1-X1 shown in FIG.
It is a longitudinal cross-sectional schematic diagram along the line.

In FIG. 3, reference numeral 601 denotes a heating means.
A sheet heater 601a elongated in a direction perpendicular to the paper surface,
The film guide 601c includes a film guide 601c for holding the film guide 01a, a stay member 601d for reinforcing the film guide, and a cylindrical fixing film 601b externally fitted to these.

Reference numeral 602 denotes a pressure roll member which forms a heating nip N by being in pressure contact with the heat generating means 601;
It is rotatably supported between the side plates of the frame 616.
Heat generating means 601 is disposed above the pressure roll member 602, and a spring 617 compressed between both ends of the stay member 601d of the heat generating means 601 and the upper cover 611 covering the upper part of the frame 616 is added. The pressure causes the pressure roll member 602 and the heat generating member 601 to be in pressure contact with each other.

Reference numeral 603 denotes a conveying means for conveying the material to be heated on the downstream side of the heating nip portion N in the direction of conveying the material to be heated.
03a.

Reference numeral 610 denotes an entrance guide for guiding the material to be heated to the heating nip portion N;
No. 01 is a guide above the entrance which prevents the transfer material curled extremely upward.

Thus, the pressing roll member 602 is driven to rotate, and accordingly, the cylindrical fixing film 601b rotates around the film guide 601c, and the heater 601 is rotated.
In the state in which the fixing nip N is heated to a predetermined temperature by the heat generated by the recording medium P, the recording material P on which the unfixed toner image t is formed by the image forming unit (not shown) is transferred to the fixing film 601b of the fixing nip N. And the pressure roller 602 are introduced with the image surface facing upward, that is, facing the fixing film surface, and the image surface is sandwiched in a state where the image surface is in close contact with the outer surface of the fixing film 601b, and the fixing is performed together with the fixing film 601b. It is transported in the nip N. In the process of being conveyed through the fixing nip N, heat from the heater 601a is applied via the fixing film 601b, and the unfixed toner image t is heated and fixed on the recording material P. The heated material P having passed through the fixing nip portion is transported by the transporting means 603, guided to the upper guide 612 'and the flapper 605, and discharged to the loading portion or the like on the downstream side in the transport direction.

In this embodiment, the upper guide 612 ′
The bosses 612 ′ a to 612 ′ d provided between the side plates of the frame 616 are positioned by fitting the bosses 612 ′ a to 612 ′ d provided at both ends in the longitudinal direction into the positioning holes 616 a to 616 d of the frame 616. Although only the left side of the apparatus is shown in FIG. 2, the right side is also substantially symmetrical, and the boss and the positioning holes 612c, 612d, 616c, 616d are respectively symmetrical with the right side 612a, 612b, 616a, 616b. Appears in The upper guide 612 ′ has
Three rollers 603a are provided, and also have a function as a support member for the rollers 603a.

Further, the upper guide 612 ′ is formed so as to abut on the upper cover 611 at a predetermined position at a central portion in the longitudinal direction.
A protrusion 612'e is provided. Accordingly, even if the upper guide 612 ′ attempts to deform in the direction opposite to the heated material conveying path due to the heat from the heat generating means 601, the protrusion 6
12'e comes into contact with and is pressed by the upper cover 611, thereby preventing deformation. Therefore, the pressure contact of the roller 603a provided on the upper guide 612 'with the transport roll 603b is appropriately maintained, and paper jam (jam of the material P to be heated) is prevented. Further, since the deformation is suppressed, it is possible to provide a guide member at a position close to the heating element, and it is possible to reduce the size of the fixing device.

(Second Embodiment) FIGS. 4 and 5 show a second embodiment. FIG. 4 is a schematic cross-sectional view of this embodiment, and FIG. 5 is a cross-sectional view in the Y1 direction shown in FIG. The present embodiment is different from the above-described embodiment in that a projection is provided on the upper cover side, and the other configuration is the same. Therefore, the same elements are denoted by the same reference numerals and repeated description is omitted. .

The upper guide 612 is positioned by fitting bosses 612a to 612d provided at both ends in the longitudinal direction into positioning holes 616a to 616d of the frame 616.

A projection 611'a is provided inside the central portion in the longitudinal direction of the upper cover 611 'so as to abut on the upper guide 612 at a predetermined position. This allows
Even if the upper guide 612 attempts to deform in the direction opposite to the heated material conveying path due to heat from the heat generating means 601, the upper guide 612 is pressed by the protrusion 611′a and prevented from being deformed. Therefore, the pressure contact of the roller 603a provided on the upper guide 612 with the transport roll 603b is also appropriately maintained, and a paper jam is prevented.

(Third Embodiment) This embodiment is the same as the second embodiment.
Compared with the embodiment of the embodiment, the configuration of the rollers of the conveying means is different,
Other configurations are the same.

In the present embodiment, the rollers 60 shown in FIG. 6 are pressed against the transport roll 603b of the transport means 603 provided downstream of the heating nip N in the direction of transport of the material to be heated.
The roller 603 "a includes a metal shaft (shaft member) 603" c and a roller portion 603 "b rotatably mounted on the metal shaft 603" c. ,
The roller portion 603 "b is made of PFA resin.

On the metal shaft 603 "c of the roller 603" a,
The ring portion of the spring 603 "d is fitted and the roller 603" a
And the metal shaft 603 "c with the spring 603" d assembled
Is inserted into the groove 612f of the upper guide 612, and the roller 603 "is pressed against the transport roll 603b by a pressing force of a spring 603" d contracted between the roller 603 "a and the upper guide 612. The metal shaft 603 "c is pressed into one of the ring portions at the end of the spring 603" d, is supported so as not to rotate, and comes off from the spring 603 "d. When attaching a single set of the roller 603 "b and the spring 603" d to the upper guide 612, the metal shaft 603 "c
To improve the assemblability.

As described above, according to the present embodiment, the shaft 603 ″
Can be prevented from being worn and broken.
Paper jam due to breakage of c can be prevented.

(Example of Image Forming Apparatus) FIG. 7 is a schematic structural view of an image forming apparatus provided with the above-mentioned heating device as an image heating means (fixing device).

A paper feed cassette 2 is provided at the lower part of the printer body 1.
The sheet material P is loaded on the sheet loading plate 201.

The sheet material P is pick-up roll 20
2 is rotated in the direction of arrow A by driving from a main motor (not shown), so that the sheet material P
paper feed roll pair 20 consisting of a and a retard roll 203b
3, after separating the sheet material P into individual sheets,
The paper is fed to a first transport roll pair 301 including a first transport roll 301a and a roller 301b. The sheet material P transported to the first transport roll pair 301 is transported to a second transport roll pair 302 including a second transport roll 302a and a roller 302b, and further transferred from the transfer photoconductor 401 and the transfer roll 402. To the transfer section.

In the transfer section, a controller (not shown)
Is written as an electrostatic latent image on the transfer photoreceptor 401 by a scanner 5, and the electrostatic latent image is developed with toner.
The image is transferred to P as an unfixed image.

The sheet material P to which the unfixed image has been transferred is introduced into the fixing device 6 shown in the above embodiment via the transfer guide 403, and is pressed and heated as a material to be heated in the heating nip N, The unfixed image is heat-fixed. In the case of single-sided printing, the sheet material P after passing through the heating nip portion N
Is transported between the flapper 605 and the upper guide 612 by driving the first paper discharge roll pair (transporting means) 603,
The face-down tray 7 is moved by a second paper discharge roll pair 701 composed of a second paper discharge roll 701a and a roller 701b.
02 is discharged and stacked.

When performing double-sided printing, the flapper 605 rotates to the position indicated by the broken line as shown by the arrow C, and the sheet material P on which the unfixed image is fixed rotates in the direction of the arrow D of the double-sided unit 8. The sheet material P is conveyed to a pair of reversing rolls 801 including a reversing roller 801 b and the sheet material P.

The sheet material P conveyed by a predetermined amount to the conveyance path 807 is conveyed to the conveyance path 808 by switching the rotation of the reversing roll 801 in the direction of arrow E, and the first double-sided conveyance roll 803a and the roller 803b Consisting of a first pair of double-sided transport rolls 803 and a second double-sided transport roll 804
a double-sided conveying roll 80 composed of a and rollers 804b
It is sent to 4.

Thereafter, at a predetermined timing, the sheet material P conveyed again to the first conveying roll pair 301 and the second conveying roll pair 302 is transferred to the transfer photosensitive member 4 similarly to the first surface.
The unfixed image is transferred to the second surface on the back side of the first surface by the transfer unit including the transfer roll 01 and the transfer roll 402.

The sheet material P to which the unfixed image on the second side has been transferred passes through the transfer guide 403, and the unfixed image on the second side is fixed again by the fixing device 6, and the first paper discharge roll pair 603 is used.
Transported to After the second surface is fixed, the flapper 605 is at the position indicated by the solid line, and the sheet material P is
1a and a second discharge roll pair 70 comprising a roller 701b
1 and is discharged and stacked on the face-down tray 702.

[0054]

As described above, according to the present invention,
By providing a projection for suppressing the thermal deformation of the guide member or the roller support member, it is possible to provide a heating device, a fixing device, and an image forming apparatus that prevent paper jam due to the thermal deformation.

Further, the present invention provides a heating device and a fixing device in which the shaft portion of the roller and the roller portion are formed as separate members, thereby suppressing abrasion of the shaft portion and preventing paper jam due to breakage of the roller. And an image forming apparatus.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment example.

FIG. 2 is a side view illustrating the first embodiment.

FIG. 3 is a cross-sectional view from the X1 direction showing the first embodiment.

FIG. 4 is a cross-sectional view illustrating a second embodiment example.

FIG. 5 is a cross-sectional view from the Yl direction showing a second embodiment.

FIG. 6 is a perspective view illustrating a third embodiment.

FIG. 7 is a schematic configuration diagram of an image forming apparatus.

FIG. 8 is a cross-sectional view showing a conventional fixing device.

FIG. 9 is a perspective view showing a conventional paper ejection roller.

[Explanation of symbols]

 1 {Printer Body} 2 Paper Cassette 201 {Sheet Loading Plate 202} Pickup Roll 203a {Paper Roll 203b} Retard Roll 301a {First Transport Roll 301b} Roller 302a} Second Transport roller 302b {roller 4} cart rich 401 {transfer photoreceptor 402} transfer roll 402 {transfer guide 5} scanner 6 {fixer 601} heater unit 601a {ceramic heater 601b} Fixing film 601c {Film guide 601d} Stay material 602} Pressure roll 603a {First paper discharge roll 603b} Roller 603 "c} Shaft 603" d {Spring 605} Flapper 606} Lower guide 610 {Inlet guide 611, 611 '} Upper cover 612, 61 ', 612 "{Upper guide 701a} First discharge roll 701b {Face down tray 8} Double-sided unit 801a {Reversing roll 801b} Reversing roller 803a {First double-sided transport roll 803b} Roller 804a {second double-sided transport roll 807} transport path

Claims (15)

[Claims] 1. A heating means, a pressing member which is in pressure contact with the heating means to form a heating nip portion of a material to be heated, and a material to be heated downstream of the heating nip portion in the direction of transport of the material to be heated. A heating member comprising: a guide member for guiding the guide member; a frame member for holding at least a part of the heat generating means, the pressure member and the guide member; and a cover member fixed to the frame member. A fixing device comprising a cover member and a projection at a predetermined position, wherein the guide member is prevented from being deformed on a side opposite to a surface of a heated material conveying path. 2. A heat generating means, a pressing member which is in pressure contact with the heat generating means to form a heating nip portion of the material to be heated, and a material to be heated downstream of the heating nip portion in the direction of transport of the material to be heated. A heating member comprising: a guide member for guiding the heating member; a frame member for holding at least a part of the heat generating means, the pressure member and the guide member; and a cover member fixed to the frame member. A fixing device, comprising a guide member and a projection at a predetermined position, wherein the guide member is prevented from being deformed on the side opposite to the surface of the material to be heated. 3. The heating device according to claim 1, wherein the guide member holds a roller of a transport unit that transports the material to be heated to a downstream side in the direction of transport of the material to be heated. Heating equipment 4. A heating means, a pressurizing member which is in pressure contact with the heating means to form a heating nip portion of the material to be heated, and transports the material to be heated downstream of the heating nip in the direction of transporting the material to be heated. A heating unit comprising: a conveying unit, a frame member that holds at least a part of the heating unit, the pressurizing member, and the conveying unit; and a cover member fixed to the frame member. And a roller pressed against the drive roll and a support member for the roller, wherein the support member is provided with a protrusion that is located at a predetermined position with the cover member. 5. A heating means, a pressurizing member which is in pressure contact with said heating means to form a heating nip portion of the material to be heated, and transports the material to be heated downstream of the heating nip in the direction of transporting the material to be heated. A heating unit comprising: a conveying unit, a frame member that holds at least a part of the heating unit, the pressing member, and the conveying unit; and a cover member fixed to the frame member. A heating device comprising: a roller pressed against the drive roll; and a support member for the roller, wherein the cover member is provided with a protrusion that is located at a predetermined position with the support member. 6. The heating device according to claim 4, wherein the protrusion is provided in a direction opposite to a direction in which the roller is pressed against the drive roll. 7. The heating device according to claim 5, wherein the protrusion is provided in the same direction as the direction in which the roller is pressed against the drive roll. 8. The apparatus according to claim 4, wherein said support member is a guide member for guiding said material to be heated at a downstream side of said heating nip portion in the direction of transport of said material to be heated. A heating device as described. 9. A heating means, a pressing member which is in pressure contact with the heating means to form a heating nip portion of the material to be heated, and a material to be heated downstream of the heating nip in the direction of transport of the material to be heated. A guide member that guides the heating target, a conveying unit that includes a conveying roll and a roller that conveys the heated material from the heating nip portion to the downstream side in the conveying direction of the heated material, and a spring member that urges the roller member toward the conveying roll. The heating device according to claim 1, wherein the roller comprises a non-rotatable shaft member and a rotatable roller portion. 10. A heating device, comprising: a pressurizing member that forms a heating nip portion of a member to be heated by being in pressure contact with the heating unit; and a conveying unit that conveys a material to be heated that has passed through the heating nip. In the heating device, the conveyance unit includes a driving roll and a roller pressed against the driving roll, and is configured using a shaft member that cannot rotate the roller and a rotatable roller portion. Heating equipment. 11. The heating device according to claim 9, wherein the shaft member is made of a metal material and the roller portion is made of a fluororesin. 12. The heating device according to claim 9, 10 or 11, wherein the roller portion is urged against the drive roll by a spring member, and at least one end of the shaft member is a shaft holding portion of the spring member. A heating device, which is press-fitted into and held by a heater. 13. The heating device according to claim 12, wherein the shaft member holding portion of the spring member has a ring shape. 14. A fixing device comprising the heating device according to claim 1 as means for heating and fixing an image formed on a recording material. 15. An image heating device, comprising: an image forming means for forming an image on a recording material; and an image heating device for heating the image formed on the recording material by the image forming means. An image forming apparatus comprising the heating device according to any one of claims 1 to 13.