JP2018013705A - Fixing device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the generation of a noise due to a separation pawl 24 of a fixing device 20.SOLUTION: A fixing device 20 comprises: a fixing roller 21 that brings its endlessly moving surface into close contact with a toner image forming surface of a recording sheet to fix a toner image; and a separation pawl 24 that is in contact with the fixing roller 21 to separate the recording sheet from the fixing roller 21. The fixing device includes a vibration attenuation member 26 formed of a viscoelastic material as vibration reduction means that reduces vibration of the separation pawl 24. In particular, the vibration attenuation member 26 is interposed between a rotation shaft 25a of a holding arm 25 that supports the separation pawl 24 in a cantilever manner and a bearing 27 that rotatably receives the rotation shaft. The vibration attenuation member 26 reduces the vibration of the separation pawl 24, and thereby reducing the generation of a noise due to the vibration of the separation pawl 24.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a fixing device and an image forming apparatus including the same.

  2. Description of the Related Art Conventionally, a fixing member for fixing a toner image by bringing a surface of the recording member into contact with a toner image forming surface and fixing the toner image, and a separation member that contacts the fixing member to separate the recording member from the fixing member A fixing device is known.

  For example, a fixing device described in Patent Document 1 is provided with a roller as a fixing member that fixes a toner image by bringing its rotating surface into close contact with a toner image forming surface of the recording sheet, and for separating the recording sheet from the roller. It has a separation claw as a separation member in contact with this roller. As the separation claw, one made of polyarylate resin is used. According to such a configuration, it is supposed that generation of abnormal noise due to friction between the separation claw and the roller can be suppressed.

  However, the separation claw made of any material increases the frictional resistance of the contact portion by depositing toner or paper powder at the entrance of the contact portion between the separation claw and the roller with long-term use. In this case, it has been found by experiments by the present inventors that noise due to vibration of the separation claw is generated.

  In order to solve the above-described problems, the present invention separates the recording member from the fixing member, and a fixing member that fixes the toner image by bringing the endlessly moving surface into close contact with the toner image forming surface of the recording member. Therefore, a fixing device having a separating member that contacts the fixing member is provided with vibration suppressing means for suppressing vibration of the separating member.

  According to the present invention, there is an excellent effect that generation of noise due to vibration of the separation member can be suppressed.

1 is a schematic configuration diagram illustrating a schematic configuration of a printer according to an embodiment. FIG. 2 is a main part configuration diagram showing a main part configuration of a fixing device of the printer. The schematic diagram which shows a vibration generator. FIG. 3 is a partial configuration diagram illustrating a part of the internal configuration of the fixing device in the printer according to the first embodiment. The fragmentary perspective view which shows a part of the internal structure from the downward direction. FIG. 9 is a partial configuration diagram illustrating a part of an internal configuration of a fixing device in a printer according to a second embodiment.

  Hereinafter, as an image forming apparatus to which the present invention is applied, an embodiment of a printer that forms an image by an electrophotographic process using a dry development method will be described. Note that the present invention is also applied to an image forming apparatus that forms an image by an electrophotographic process using a wet development method, and an image forming apparatus that forms an image by a toner projection method as described in JP-A-2002-307737. Is possible.

  First, a basic configuration of the printer according to the embodiment will be described. FIG. 1 is a schematic configuration diagram illustrating a schematic configuration of a printer according to an embodiment. The printer includes a paper feed cassette 1, a paper feed path 2, a registration roller pair 3, a photoconductor 4, a drum cleaning device 5, a charging roller 6, an optical writing device 7, a developing device 8, a transfer roller 9, a fixing device 20, and the like. It has.

  The paper feed cassette 1 includes a storage unit that stores a plurality of recording sheets S serving as recording members in a stacked state, and a paper feed roller 1a that separates and feeds the uppermost recording sheet S in the sheet bundle one by one. have. The recording sheet S sent out to the paper feed path 2 by the rotational drive of the paper feed roller 1 a hits the registration nip of the registration roller pair 3 disposed in the paper feed path 2 and temporarily stops. At this time, the skew of the recording sheet S is corrected. After that, the registration roller pair 3 starts to rotate at a timing to synchronize the recording sheet S with a toner image on the surface of the photoreceptor 4 (described later) in a transfer nip (described later), while feeding the recording sheet S into the transfer nip. Then, the toner is fed from the transfer nip toward the transfer nip.

  Around the drum-shaped photoconductor 4, a drum cleaning device 5, a charging roller 6, an optical writing device 7, a developing device 8, and the like are disposed. The surface of the photoreceptor 4 that is rotationally driven in the clockwise direction in the figure passes through a contact position with the charging roller 6 to which a charging bias is applied, and is discharged by a discharge between its surface and the charging roller 6. The toner is uniformly charged to the same polarity as the normal charging polarity of the toner described later. The surface area of the photoreceptor that is uniformly charged in this manner is hereinafter referred to as a background portion.

  An optical writing device 7 having a known laser optical system drives a laser diode based on image information and emits laser light L from the laser diode. The laser light L is reflected by a polygon mirror that is driven to rotate, and reaches the surface of the photoconductor 4 while being deflected in the main scanning direction along the rotation axis direction of the photoconductor 4. Thereby, the surface of the photoreceptor 4 is optically scanned. Of the entire area on the surface of the photoconductor 4, the region irradiated with the laser light L is attenuated in potential and becomes an electrostatic latent image.

  The electrostatic latent image formed on the surface of the photosensitive member 4 in this way passes through the developing region which is the region facing the developing device 8 as the photosensitive member 4 rotates, and the developing roller of the developing device 8 The toner carried on the surface of 8a is adhered and developed. By this development, a toner image is formed on the surface of the photoreceptor 4. The developing area includes an electrostatic latent image on the photosensitive member 4 and the surface of the developing roller 8a to which a developing bias having an absolute value that is the same polarity as the charging polarity of the toner and smaller than the background potential is applied. In the meantime, a developing potential for electrostatically moving the toner from the roller side toward the photoreceptor 4 side acts. In addition, a background potential that electrostatically moves toner from the photosensitive member 4 side toward the developing roller 8a acts between the background portion of the photosensitive member 4 and the developing roller 8a. Due to the synergistic action of these potentials, the toner selectively adheres only to the electrostatic latent image in the entire area of the photoreceptor 4.

  The toner image that has passed through the development area enters the transfer nip due to the contact between the photoconductor 4 and the transfer roller 9 as the photoconductor 4 is driven to rotate. In this transfer nip, the toner is directed from the photoconductor 4 side to the transfer roller 9 side between the surface of the photoconductor 4 and a transfer roller 9 to which a transfer bias having a polarity opposite to the normal charging polarity of the toner is applied. Thus, a transfer electric field for electrostatic movement is formed.

  The toner image on the photoconductor 4 that has entered the transfer nip is brought into close contact with the recording sheet S that has been fed into the transfer nip in a timely manner by the registration roller pair 3. Then, it is transferred onto the surface of the recording sheet S by the action of a transfer electric field or nip pressure.

  The recording sheet S having the toner image transferred onto its surface in this way passes through the transfer nip as the photosensitive member 4 and the transfer roller 9 are driven to rotate, and is then fed into the fixing device 20. In the fixing device 20, a fixing nip is formed by contact between a fixing roller 21 as a fixing member that contacts the toner image transfer surface of the recording sheet S and a pressure roller 22 that is pressed toward the fixing roller 21. The recording sheet S sandwiched in the fixing nip is heated by the fixing roller 21 including a halogen lamp as a heat generation source or is pressed in the nip. As a result, the toner is softened and the toner image is fixed on the toner image forming surface of the recording sheet S. The recording sheets S discharged from the fixing device 20 are stacked outside the apparatus.

  Untransferred toner that has not been transferred to the recording sheet S adheres to the surface of the photoreceptor 4 after passing through the transfer nip. The untransferred toner reaches a position facing the drum cleaning device 5 as the photosensitive member 4 is driven to rotate. Then, it is scraped off from the surface of the photoreceptor 4 by the cleaning blade 5 a of the drum cleaning device 5. Thereafter, the surface of the photoconductor 4 reaches a contact position with the charging roller 6 and is uniformly charged again.

  As a transfer unit, a corotron charger or the like may be used instead of the transfer roller 9.

  FIG. 2 is a main part configuration diagram showing a main part configuration of the fixing device 20. The outer surface of a hollow cored bar made of stainless steel or aluminum in the fixing roller 21 of the fixing device 20 is coated with a release promoting layer for improving the release property from toner and paper powder. As a material for the release promoting layer, it is desirable to use a material having heat resistance and low surface energy. Examples thereof include silicone resin, fluororesin, polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and tetrafluoroethylene-hexafluoropropylene copolymer (FEP). It is possible to coat the outer surface of the metal core by heat-shrinking a heat-resistant tube made of such a polymer resin. In order to improve the abrasion resistance, 3 to 10 [mass%] of an abrasion resistance additive such as carbon or SiC may be added to the above-described polymer resin. When the wear resistance additive is added in an amount of 3% by mass or more, sufficient wear resistance is obtained. However, when the additive amount is more than 10% by mass, the surface exposure rate of the wear resistance additive becomes too high. In addition, the toner releasability is deteriorated.

  A halogen heater 21 a as a heat source is disposed in the hollow of the core of the fixing roller 20. As the heat source, a different one from the halogen heater 21a, for example, induction heating or a planar heating element may be used.

  An elastic layer is coated on the outer surface of the metal core made of stainless steel, aluminum, or the like in the pressure roller 22 that forms a fixing nip while being pressed against the fixing roller 21 to form a fixing nip. Examples of the material for the elastic layer include heat-resistant elastic materials such as fluorine rubber and silicone rubber. The outer surface of the elastic layer is covered with a release promoting layer made of a fluorine resin or the like. Further, the elastic layer of the pressure roller 22 is elastically deformed by a biasing force such as a spring that biases the pressure roller 22 toward the fixing roller 21, thereby fixing the fixing nip having a wide width (length in the roller surface moving direction). Can be formed.

  In the vicinity of the fixing roller 23, a temperature sensor 23 such as a thermistor is disposed so as to detect the surface temperature of the fixing roller 23. The detection result of the surface temperature of the fixing roller 23 by the temperature sensor 23 is sent to a heating control controller as a control circuit. The heating controller performs on / off control of the output from the fixing power source that outputs the voltage supplied to the halogen heater 21a so as to maintain a predetermined surface temperature range. As a result, the surface temperature of the fixing roller 23 is positioned near the target temperature. In this printer, the target temperature is set to 160 [° C.] based on the results of toner viscoelasticity and fixability tests.

  Of the entire area of the outer surface of the fixing roller 21 in the circumferential direction, the tip of the separation claw 24 as a separation member is in contact with a portion near the exit of the fixing nip. Even if the leading edge of the recording sheet S after passing through the fixing nip remains in close contact with the surface of the fixing roller 21 due to the viscosity of the toner, the leading edge is forcibly separated from the surface of the fixing roller 21 by the separation claw 24. Is done. A plurality of separation claws 24 may be arranged side by side in the direction of the rotation axis of the fixing roller 21.

  In the fixing device 20 having such a configuration, when toner or paper dust accumulates near the entrance of the contact portion between the separation claw 24 and the fixing roller 21 with long-term use, the separation claw 24 and the fixing roller 21 are accumulated. Increase the friction force. Then, it became clear that the stick-slip phenomenon of the separation claw 24 occurred, and the separation claw 24 generated noise while vibrating at a natural frequency called self-excited vibration.

  FIG. 3 is a schematic diagram showing a vibration generator. In this vibration generator, an endless belt 105 is stretched by a driving roller 106 that is driven to rotate clockwise in the drawing and a driven roller 107. A mass body 104 of mass m [kg] is placed on the extended surface of the endless belt 105. The mass body 104 is connected to the wall 101 via a spring 102 having a spring constant k [N / m] and a damper 103 having a damping coefficient c [Ns / m] arranged in parallel.

When the endless belt 105 moves endlessly, the endless belt 105 and the mass body 104 rub against each other against the frictional force f [N], and the mass body 104 vibrates with this rubbing. The equation of motion of the mass body 104 at this time is expressed by the following equation (1).

  When the damping coefficient c in this equation of motion is negative, the vibration of the mass body 104 is amplified. However, since the damper 103 attenuates the motion of the mass body 104, the damping device shown in FIG. c becomes positive. As the absolute value increases, the damping rate increases and the vibration of the mass body 104 is reduced. Thereby, the noise by the vibration of the mass body 104 is reduced.

  In the printer according to the embodiment, the fixing roller 21 corresponds to the endless belt 105 of the vibration generating device, and the separation claw 24 corresponds to the mass body 104. When the inventors conducted an experiment with a printer testing machine having the same configuration as that of the printer according to the embodiment, paper powder and toner are brought into contact with the fixing roller 21 and the separation claw 24 with long-term use. As it accumulated at the entrance, the noise of the frequency of about 3000 [Hz] was generated by the vibration of the separation claw 24.

  As a method for suppressing the vibration of the mass body 104 in the vibration generator described above, based on the principle of vibration generation, there are methods such as increasing the spring constant k, decreasing the frictional force f, or increasing the damping coefficient c. . Increasing the spring constant k is equivalent to increasing the pressing force of the separation claw 24 against the fixing roller 21 in the printer according to the embodiment. However, if this is done, the wear of the separation claw 24 is accelerated or the fixing roller 21 is damaged. Or the driving torque of the fixing roller 21 is increased.

  In addition, reducing the frictional force f corresponds to reducing the frictional force between the separation claw 21 and the fixing roller 21 in the printer according to the embodiment. As the method, a lubricant may be applied to the surface of the fixing roller 21, but this is not preferable because the lubricant affects the image quality and increases the running cost.

  Further, increasing the damping coefficient c corresponds to providing vibration suppression means such as a damper in the printer according to the embodiment. According to this method, the image quality is not affected, the wear of the separation claw 21 is accelerated, the fixing roller 21 is damaged, and the driving torque of the fixing roller 21 is not increased.

  Therefore, in the printer according to the embodiment, the fixing device 20 is provided with a vibration suppression unit that suppresses the vibration of the separation claw 24. By suppressing the vibration of the separation claw 24 by this vibration suppressing means, the generation of noise due to the vibration of the separation claw 24 can be suppressed.

  Next, printers according to the respective examples in which a more characteristic configuration is added to the printer according to the embodiment will be described. Unless otherwise specified below, the configuration of the printer according to each example is the same as that of the embodiment.

[First embodiment]
FIG. 4 is a partial configuration diagram illustrating a part of the internal configuration of the fixing device 20 in the printer according to the first embodiment. FIG. 5 is a partial perspective view showing a part of the internal configuration of the fixing device 20 in the printer according to the first embodiment from below. In these drawings, the separation claw 24 is fixed and supported by a holding arm 25 as a holding member, and its free end is brought into contact with the fixing roller 21.

  The holding arm 25 is formed with a rotating shaft 25a protruding from each of the two side surfaces. Each rotating shaft 25a is rotatably received by a groove of a bearing 27 having a U-shaped groove. One end of a tension spring 28 is fixed to the upper portion of the holding arm 25, and the other end of the tension spring 28 is fixed to a casing 29 of the fixing device 20. When the tension spring 28 pulls the upper part of the holding arm 25 toward the casing 29 by its restoring force, the holding arm 25 tries to rotate in the direction of arrow A in the figure around the rotation shaft 25a. The rotation is prevented by the front end abutting against the fixing roller 21. That is, the separation claw 24 is pressed against the fixing roller 21 by the spring force of the tension spring 28. As the tension spring 28, a spring constant having a linear pressure of 10 to 50 [mN / mm] at the contact portion between the tip of the separation claw 24 and the fixing roller 21 that are in line contact with each other is used.

  A vibration damping member 26 made of a viscoelastic material is interposed between the rotation shaft 25 a and the bearing 27. The rotation shaft 25a is press-fitted into the hollow of the cylindrical vibration attenuation member 26, so that the vibration attenuation member 26 is covered on the outer peripheral surface of the rotation shaft 25a. When the separation claw 24 vibrates and the vibration is transmitted to the holding arm 25, the vibration attenuating member 26 interposed between the rotation shaft 25a of the holding arm 25 and the bearing 26 causes the rotation shaft 25a of the holding arm 25 and the main body portion. The vibration of the separation claw 24 is attenuated via the. Thereby, the vibration of the separation claw 24 is suppressed.

As the vibration damping member 26, one made of silicone rubber is used. The physical properties of this silicone rubber are as follows.
-Storage elastic modulus G ′ at 0 to 50 ° C. = 1.0E + 5 [Pa]
-Loss elastic modulus G ″ at 0 to 50 ° C. = 2.0E + 4 [Pa]
Loss tangent (tan δ) at 0 to 50 ° C. = 0.2

  The storage elastic modulus G ′ and the loss elastic modulus G ″ were measured as follows. That is, first, a sample was molded into a cubic shape of 5 mm × 5 mm × 5 mm and set in a dynamic viscoelasticity measuring apparatus. At this time, the laboratory environment is stabilized at room temperature, and the measurement conditions are set to frequency = 10 [Hz], 100 [Hz], strain amount = 20 [%], measurement mode = compression, and storage elastic modulus G ′. The loss elastic modulus G ″ was measured. After completion of the measurement, the temperature was raised to 50 [° C.] and measured in the same manner. Thereafter, the loss tangent (tan δ) was determined using the equation: loss tangent (tan δ) = G ″ / G ′.

  The two bearings 27 are integrally formed with the casing 29. Since the setting of the separation claw 24 is completed simply by fitting the rotation shaft 25a of the holding arm 25 and the vibration damping member 26 into the U-shaped groove of the bearing 27, the assemblability is good.

  The separation claw 24 is made of PEEK (polyether ether ketone) or PEK (polyether ketone). Since PEEK and PEK are excellent in mechanical strength, the life of the separation claw 24 can be extended. On the other hand, there is a drawback that vibration is easily generated. However, by suppressing the vibration by the vibration damping member 26, both the extension of the life of the separation claw 24 and the suppression of noise due to the vibration of the separation claw 24 are achieved. Is done.

  The contact surface of the separation claw 24 with the fixing roller 21 is coated with a release promoting layer made of a polymer resin such as PTFE, PFA, FEP. Thereby, sticking of toner or paper powder to the surface of the separation claw 24 can be suppressed.

  The inventors prepared a printer tester with a modified version of MP 1601 manufactured by Ricoh Co., Ltd. The fixing device is modified to the same configuration as that of the printer according to the first embodiment. In this printer testing machine, as a recording sheet S, A4 size commercially available PPC (Plain Paper Copier) paper containing 25% by weight of heavy calcium carbonate was set in a laterally transported posture and test printing was performed. . As a test image to be printed, a document image having an image area ratio of 10% was adopted. Each character in the document image extends over almost the entire effective image area on the paper.

  First, a test print for comparison was performed as a test print. In this comparative test print, a holding arm 25 that does not have the vibration damping member 26 attached to the rotating shaft 25a is used. When the test print for comparison was repeated until the noise from the separation claw 24 was heard by repeating the single print job for each sheet instead of the continuous print job, noise was recognized when about 5,000 sheets were printed. It was.

  Next, a test print of the first example was performed. In the test print of the first embodiment, the holding arm 25 having the vibration damping member 26 mounted on the rotating shaft 25a is employed. When test images were printed in the same manner as the test print for comparison, no noise was generated from the separation claws 24 even when 10,000 or more prints were made. Thereby, the effect of the printer according to the first example was proved.

[Second Embodiment]
FIG. 6 is a partial configuration diagram illustrating a part of the internal configuration of the fixing device 20 in the printer according to the second embodiment. Also in the fixing device 20, the holding arm 25 that is rotatable around the rotation shaft 25 a is fixed to the holding arm 25 by applying a pulling force (biasing force) to the holding arm 25 that is a biasing means. The leading end of the separated claw 24 is pressed against the fixing roller 21.

  As shown in the figure, unlike the first embodiment, a cylindrical vibration damping member is not attached to the rotating shaft 25a. Instead, the casing 29 is provided with a casing protrusion 29 a that protrudes directly below the tension spring 28 toward the holding arm 25. Further, the block-like vibration damping member 30 is bonded and fixed to a region of the holding arm 25 facing the casing protrusion 29a. The facing region is a region that is drawn by the pulling force of the pulling spring 28 and approaches the casing protruding portion 29a in the entire region of the holding arm 25. When the upper portion of the holding arm 25 is pulled by the tension spring 28, the block-shaped vibration damping member 30 bonded and fixed to the holding arm 25 hits the tip of the casing protruding portion 29a. Accordingly, the vibration of the separation claw 24 is attenuated by the vibration damping member 30 through the holding arm 25 by pressing the block-like vibration damping member 30 against the holding arm 25.

  In this configuration, the separation pawl 24 is pressed against the fixing roller 21 and the vibration damping member 30 is pressed against the holding arm 25 using the spring force of the tension spring 28. Accordingly, the spring force of the tension spring 28 can be effectively used not only as a force for pressing the separation claw 24 against the fixing roller 21 but also as a force for enhancing the vibration damping effect of the separation claw 24.

  The vibration damping member 30 is made of silicone rubber. The physical properties of this silicone rubber are the same as the physical properties of the silicone rubber described in the first embodiment.

  The inventors prepared a printer tester with a modified version of MP 1601 manufactured by Ricoh Co., Ltd. The fixing device is modified to have the same configuration as that of the printer according to the second embodiment. Using this printer tester, the second example test print was carried out in the same manner as the first example test print. Then, even when 10,000 or more sheets were printed, no noise was generated from the separation claw 24. Thereby, the effect of the printer according to the second embodiment was proved.

What was demonstrated above is an example, and there exists an effect peculiar for every following aspect.
[Aspect A]
Aspect A includes a fixing member (for example, a fixing roller 21) that fixes a toner image by bringing the endlessly moving surface thereof into close contact with the toner image forming surface of the recording member (for example, recording sheet S), and from the fixing member to the recording member. In a fixing device (for example, the fixing device 20) having a separation member (for example, the separation claw 24) that contacts the fixing member to separate the fixing member, a vibration suppressing unit that suppresses vibration of the separation member is provided. To do.

  In aspect A, generation of noise due to vibration of the separation member can be suppressed by suppressing vibration of the separation member by the vibration suppression means.

[Aspect B]
Aspect B is characterized in that, in aspect A, a vibration attenuating member (for example, vibration attenuating members 26 and 30) for attenuating the vibration of the separation member is used as the vibration suppressing means. In such a configuration, the vibration of the separation claw can be suppressed by the vibration damping action of the vibration damping member.

[Aspect C]
Aspect C has a storage elastic modulus G ′ at 0 to 50 [° C.] of 1.0E + 6 [Pa] or less as the vibration damping member in aspect B, and a loss tangent (tan δ) at 0 to 50 [° C.]. ) Is 0.1 or more. In this configuration, the vibration damping member having a storage elastic modulus G ′ of 0 to 50 ° C. exceeding 1.0E + 6 [Pa] and a loss tangent (tan δ) of 0 to 50 ° C. being less than 0.1. The vibration damping effect of the separating member can be enhanced as compared with the case of using.

[Aspect D]
Aspect D is characterized in that, in aspect C, the vibration damping member is made of silicone rubber. In such a configuration, the following physical properties required for the vibration damping member can be easily realized by using silicone rubber widely distributed in the market as the material of the vibration damping member. That is, the physical properties are that the storage elastic modulus G ′ at 0 to 50 [° C.] is 1.0E + 6 [Pa] or less, and the loss tangent (tan δ) at 0 to 50 [° C.] is 0.1 or more. .

[Aspect E]
Aspect E is any one of aspects B to D, in which the separation member is held by a holding member (for example, holding arm 25) that is rotatable about a rotation shaft (for example, rotation shaft 25a), and the rotation shaft The vibration damping member fixed on the outer peripheral surface of the rotating shaft is interposed between a bearing (for example, the bearing 27) that receives the rotation of the rotating shaft and the rotating shaft. In such a configuration, it is possible to attenuate the vibration of the separation member by utilizing the space between the rotation shaft and the bearing.

[Aspect F]
Aspect F is characterized in that, in aspect E, the rotating shaft is press-fitted into the cylindrical vibration damping member. With this configuration, the vibration damping member can be easily attached to the rotation shaft.

[Aspect G]
Aspect G is any one of aspects B to D, in which the separation member is held by a holding member that is rotatable about a rotation axis, and is applied to the holding member by an urging force of an urging means (for example, a tension spring 28). On the other hand, by applying a rotational force around the rotation shaft, the separation member held by the holding member is pressed against the fixing member, and the vibration damping member is pressed against the holding member. It is characterized by that. In such a configuration, the urging force of the urging means can be effectively used not only as a force for pressing the separation member against the fixing member but also as a force for enhancing the vibration damping effect of the separation member.

[Aspect H]
Aspect H is characterized in that in aspect G, the vibration damping member is bonded to the holding member. In such a configuration, the vibration damping member can be fixed to the holding member without impairing the viscoelasticity of the vibration damping member.

[Aspect I]
Aspect I is characterized in that in any of the aspects A to H, the separating member is made of PEK (polyether ketone) or PEEK (polyether ether ketone). With such a configuration, the life of the separating member can be extended.

[Aspect J]
Aspect J is a toner image forming means for forming a toner image on a recording member (for example, comprising a photosensitive member 4, a drum cleaning device 5, a charging roller 6, an optical writing device 7, a developing device 8, a transfer roller 9, etc.) And a fixing unit for fixing a toner image on the recording member, any one of modes A to I is used as the fixing unit.

4: Photoconductor (part of toner image forming means)
5: Drum cleaning device (part of toner image forming means)
6: Charging roller (part of toner image forming means)
7: Optical writing device (part of toner image forming means)
8: Developing device (part of toner image forming means)
9: Transfer roller (part of toner image forming means)
20: Fixing device 21: Fixing roller (fixing member)
24: Separation claw (separation member)
25: Holding arm (holding member)
25a: rotating shaft 26: vibration damping member 27: bearing 28: tension spring (biasing means)
30: Vibration damping member

JP-A-60-51868

Claims (10)

A fixing member that fixes a toner image by closely contacting a surface of the recording member on which the toner image is formed, and a separation member that contacts the fixing member to separate the recording member from the fixing member; In the fixing device,
A fixing device comprising vibration suppression means for suppressing vibration of the separation member. The fixing device according to claim 1.
A fixing device using a vibration damping member that attenuates vibration of the separation member as the vibration suppressing means. The fixing device according to claim 2.
As the vibration damping member, the storage elastic modulus G ′ at 0 to 50 [° C.] is 1.0E + 6 [Pa] or less,
A fixing device having a loss tangent (tan δ) at 0 to 50 ° C. of 0.1 or more is used. The fixing device according to claim 3.
A fixing device using a member made of silicone rubber as the vibration damping member. The fixing device according to any one of claims 2 to 4,
The separation member is held by a holding member that can rotate around a rotation shaft, and is fixed on the outer peripheral surface of the rotation shaft between a bearing that rotatably receives the rotation shaft and the rotation shaft. A fixing device having the vibration damping member interposed therebetween. The fixing device according to claim 5.
A fixing device, wherein the rotation shaft is press-fitted into the cylindrical vibration damping member. The fixing device according to any one of claims 2 to 4,
By holding the separation member on a holding member that is rotatable about a rotation axis, and applying a rotational force about the rotation axis to the holding member by an urging force by an urging means, A fixing device, wherein the separation member held by a holding member is pressed against the fixing member, and the vibration damping member is pressed against the holding member. The fixing device according to claim 7.
A fixing device, wherein the vibration damping member is bonded to the holding member. The fixing device according to any one of claims 1 to 8,
A fixing device using a member made of PEK (polyetherketone) or PEEK (polyetheretherketone) as the separating member. An image forming apparatus comprising: a toner image forming unit that forms a toner image on a recording member; and a fixing unit that fixes the toner image on the recording member.
An image forming apparatus using the fixing device according to claim 1 as the fixing unit.

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