JP7180171B2 - Fixing device and image forming device - Google Patents

Description

The present invention relates to fixing devices and image forming apparatuses.

An electrophotographic fixing device heats and melts toner on a recording medium with a heater or the like, and presses the toner image with a pressure member to fix the toner image on the recording medium. Such a fixing device includes a cleaning section that cleans the surface of the abutment member with which the separation claw abuts, and a separation claw that abuts the abutment member and peels off the recording medium. Devices for contacting and separating are known.

Further, in order to supply the lubricant when the separation claw is in contact with the contact member, there is provided a device that interlocks the separation claw with a cleaning unit that supplies the lubricant to bring the separation claw into contact with and separate from the contact member. (see, for example, Patent Document 1).

However, in the device disclosed in Patent Document 1, the timing at which the separation claw and the cleaning portion contact the contact member and the timing at which they separate from the contact member are not defined. When the pressurizing separation claw or the like is brought into contact with the contact member such as the pressure member, the foreign matter collected on the pressure separation claw or the like may fall off, and at this time, the cleaning portion is separated from the contact member. In such a case, the foreign matter may not be collected by the cleaning section and adhere to the recording medium, resulting in an abnormal image.

SUMMARY OF THE INVENTION It is an object of the present invention to reliably collect foreign matter in a cleaning section when the foreign matter accumulated in the pressurizing separation claw falls off.

A fixing device according to an aspect of the disclosed technique includes a fixing member that is heated by a heating unit, and a pressing device that is arranged so as to be able to press at least a part of the fixing member and that forms a nip portion between the fixing member and the fixing member. a member, a cleaning unit having a cleaning section provided to be able to contact and separate from the pressure member, a pressure separating claw provided to be capable of contacting and separating from the pressure member, and the pressure separation claw. and a spring for applying force to the separation stay in a direction away from the pressure member, wherein the pressure separation claw unit further includes the cleaning unit is attached to one end of a transmission member, which is a member for transmitting the force of contacting and separating from the pressure member to the pressure separation claw unit, and the other end of the transmission member contacts the cleaning unit and the pressure is applied to the cleaning unit. The pressure separation claw is separated from the pressure member at the same time as the cleaning portion is separated from the pressure member or earlier than the timing, and at the same time as the cleaning portion is brought into contact with the pressure member. or after the timing, the transmission member abuts against the pressure member, and the transmission member moves the cleaning unit.
The cleaning unit is separated from the pressure member so that the force with which the separation stay is pushed by the transmission member is greater than the force of the spring when the contact is in contact with the pressure member. It is characterized in that the separation stay is arranged so that the force of being pushed by the transmission member is smaller than the force of the spring .

According to the embodiment of the present invention, when foreign matter accumulated in the pressure separating claw falls off, the foreign matter can be reliably collected by the cleaning section.

1 is a diagram illustrating an example of a configuration of an image forming apparatus according to an embodiment; FIG. 4 is a diagram showing an example of the configuration of a fixing unit according to the embodiment; FIG. It is a figure which shows the case where the cleaning unit which concerns on embodiment is spaced apart from the pressurizing member. FIG. 5 is a diagram showing the relationship between the amount of bite into the pressure member of the cleaning unit according to the embodiment and the biasing force of the pressure separation section to the pressure member.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals, and redundant description may be omitted.

The recording medium of the embodiment is paper, plastic sheet, or the like. In the following, a case where the recording medium is paper will be described as an example, and the recording medium will simply be referred to as "paper". Note that image formation, recording, printing, copying, printing, etc. in the terms of the embodiments are all synonymous.

In the embodiments, an electrophotographic image forming apparatus having a secondary transfer mechanism called a tandem system will be described as an example.

[First Embodiment]
(Configuration of image forming apparatus)
A first embodiment will be described with reference to the drawings. FIG. 1 is a diagram showing an example of the configuration of an image forming apparatus according to this embodiment. As shown in FIG. 1, the image forming apparatus 100 has an intermediate transfer unit, image forming devices 20 for each color, an exposure section 21 , a secondary transfer unit 22 and a fixing unit 25 .

The intermediate transfer unit has an intermediate transfer belt 10 which is an endless belt, three support rollers 14 to 16 and an intermediate transfer member cleaning unit 17 . The intermediate transfer belt 10 is entrained around supporting rollers 14 to 16 and rotates clockwise. The intermediate transfer member cleaning unit 17 is provided between the second support roller 15 and the third support roller 16, and removes residual toner remaining on the surface of the intermediate transfer belt 10 after transferring the image.

The image forming device 20 is installed between the first support roller 14 and the second support roller 15 in order of yellow, magenta, cyan, and black in the conveying direction of the intermediate transfer belt 10 .

The image forming device 20 has a cleaning unit, a charging roller 18, a static eliminator, a developing device, and a photosensitive drum 40 for each color. The exposure unit 21 is provided above the image forming device 20 and exposes the photosensitive drums 40 of each color to laser light to form latent images on the photosensitive drums 40 .

The image forming device 20 forms a toner image on the intermediate transfer belt 10 by developing the latent image on the photoreceptor drum 40 for each color with a developing device. Note that the image forming apparatus 20 may be detachable from the image forming apparatus 100 .

The secondary transfer unit 22 has two rollers 23 and a secondary transfer belt 24 and is provided below the intermediate transfer belt 10 . The secondary transfer belt 24 is an endless belt and is looped around two rollers 23 to rotate. The roller 23 and the secondary transfer belt 24 push up the intermediate transfer belt 10 and are placed in contact with the third support roller 16 . The secondary transfer belt 24 transfers the toner image formed on the intermediate transfer belt 10 onto the paper P, and causes the paper P to bear the unfixed toner image.

The fixing unit 25 is provided beside the secondary transfer unit 22 . The fixing unit 25 has a fixing member 60 and a pressure member 61 forming a nip portion with the fixing member 60 . The paper P bearing the unfixed toner image is conveyed to the nip portion of the fixing unit 25, and the fixing unit 25 fixes the unfixed toner image onto the paper P. FIG. Incidentally, the configuration of the fixing unit 25 will be described later in detail.

A sheet reversing unit 28 is provided below the secondary transfer unit 22 and the fixing unit 25 . The sheet reversing unit 28 reverses the front side and the back side of the paper P that has been conveyed. The sheet reversing unit 28 is used when the image forming apparatus 100 forms an image on the front side of the sheet P and then forms an image on the back side.

An automatic document feeder (ADF) 400 conveys the paper P onto the contact glass 32 when the start button of the operation unit is pressed and the paper P is on the paper feed tray 30 . When there is no paper P on the paper feed tray 30, the automatic paper feeder 400 activates the image reading unit 300 to read the paper P on the contact glass 32 placed by the user.

The image reading unit 300 has a first carriage 33, a second carriage 34, an imaging lens 35, a CCD (Charge Coupled Device) 36, and a light source. The image reading unit 300 drives the first carriage 33 and the second carriage 34 to read the paper P on the contact glass 32 .

A light source of the first carriage 33 irradiates the paper P on the contact glass 32 with light. The irradiated light is reflected by the paper P on the contact glass 32 and then reflected toward the second carriage 34 by the first mirror of the first carriage 33 . The light reflected by the second carriage 34 is imaged at the position of the CCD 36 by the imaging lens 35 and picked up by the CCD 36 . The image forming apparatus 100 generates yellow, magenta, cyan, and black image data based on the output signal of the CCD 36 .

The image forming apparatus 100 starts the intermediate transfer belt when a start button of the operation unit is pressed, when an image forming instruction is received from an external device such as a PC (Personal Computer), or when a facsimile output instruction is received. Start 10 rotations.

When the intermediate transfer belt 10 starts rotating, the image forming device 20 starts forming an image. The paper P having the toner image transferred thereon and bearing the unfixed toner is conveyed to the fixing unit 25 . The unfixed toner image is fixed by the fixing unit 25 to form an image on the paper P. FIG.

The paper feed table 200 has a paper feed roller 42 , a paper feed unit 43 , a separation roller 45 and a transport roller unit 48 . The paper feed unit 43 has a plurality of paper feed trays 44 , and the transport roller unit 48 has transport rollers 47 .

The paper feed table 200 selects and rotates one of the paper feed rollers 42 . The paper feed unit 43 selects one paper feed tray from among the plurality of paper feed trays 44 and feeds the paper P set in the paper feed tray. The paper P to be fed is separated by the separation roller 45 and conveyed to the conveying path 46 . The transport rollers 47 transport the paper P to the image forming apparatus 100 through the transport path 46 .

The paper P conveyed to the image forming apparatus 100 is further conveyed to the position of the registration roller 49 through the paper feed path 53, hits the registration roller 49, and temporarily stops. The paper P is conveyed to the secondary transfer unit 22 at the timing when the toner image on the intermediate transfer belt 10 enters the secondary transfer unit 22 . The secondary transfer unit 22 transfers the toner image on the intermediate transfer belt 10 to the paper P and causes the paper P to bear the unfixed toner image.

Note that the paper P may be fed from the manual feed tray 51 . When paper P is fed from manual feed tray 51 , image forming apparatus 100 rotates paper feed roller 50 . The paper feed roller 50 separates one sheet from a plurality of papers on the manual feed tray 51 and feeds the separated paper P to the paper feed path 53 . The paper P fed to the paper feed path 53 is further conveyed to the position of the registration rollers 49 . The processing after the paper P is conveyed to the registration rollers 49 is the same as the case of feeding the paper P from the paper feed table 200 .

The paper P is discharged after being fixed by the fixing unit 25 . The discharged paper P is conveyed to the position of the discharge roller 56 by the switching claw 55 . The ejection roller 56 conveys the paper P to the paper ejection tray 57 and ejects it.

The switching claw 55 may send the paper P ejected from the fixing unit 25 to the sheet reversing unit 28 . The sheet reversing unit 28 reverses the front side and the back side of the paper P that has been sent. An image is formed on the back side of the reversed sheet P in the same manner as the front side, and the sheet P is conveyed to the discharge tray 57 . The image forming apparatus 100 forms an image on the sheet P in this way.

(Structure of fixing unit)
Next, the fixing unit 25 will be described.

FIG. 2 is a diagram showing an example of the configuration of the fixing unit 25 according to this embodiment.

The fixing unit 25 has a fixing member 60 , a pressure member 61 , a non-contact separation plate 62 , a pressure separation claw unit 63 , a cleaning unit 64 and a contact/separation drive mechanism 65 . The fixing member 60 also has a fixing roller 601 , a heating roller 602 and a fixing belt 603 . The fixing unit 25 is an example of a "fixing device".

The fixing roller 601 is a cylindrical roller and is rotatably held in the housing of the fixing unit 25 . The surface of the fixing roller 601 is covered with silicone rubber or silicone sponge.

The heating roller 602 is a metal pipe and a rotating body having a heater 604 inside. The heating roller 602 is covered with a tube whose surface is coated with fluorine resin. The heating roller 602 is also rotatably held in the housing of the fixing unit 25 like the fixing roller 601 .

The heater 604 is, for example, a halogen heater, a ceramic heater, an IH heater, or the like, and generates heat when supplied with power. Radiation heat from the heater 604 heats the outer peripheral portion of the heating roller 602 . A plurality of heaters 604 may be provided at the axial center and both ends of the heating roller 602 to independently heat the axial center and both ends of the heating roller 602 . Heat generation of the heater 604 may be controlled based on the temperature of the heating roller 602 or the fixing belt 603 detected by a temperature sensor. The heater 604 is an example of a "heater".

The fixing belt 603 is a thin flexible endless belt member, and is wound around the fixing roller 601 and the heating roller 602 . The fixing belt 603 is based on a metal film such as nickel (Ni) or stainless steel (SUS), or a resin film such as polyimide (PI) or polyamideimide (PAI). The surface of the substrate is coated with silicone rubber, and the surface layer of the silicone rubber is coated with a fluororesin. The fixing belt 603 is heated from inside by the heating roller 602 .

The fixing belt 603 can rotate while being stretched between the fixing roller 601 and the heating roller 602 . In this case, one of the fixing roller 601 and the heating roller 602 may be a driving roller, and the other may be a driven roller.

The pressure member 61 is a cylindrical roller and is rotatably held in the housing of the fixing unit 25 . The pressure member 61 has a surface covered with silicone rubber or silicone sponge. The pressure member 61 is arranged so as to be able to press at least a part of the fixing roller 601 with the fixing belt 603 interposed therebetween.

At the nip portion 251 between the fixing roller 601 and the pressure member 61, the paper P carrying the unfixed toner is heated by the fixing belt 603 heated by the heating roller 602, and pressed by the pressure member 61 to remove the unfixed toner. The toner is fixed on the paper P.

A margin of about 3 to 5 mm is provided at the leading edge of the paper P, and the margin does not receive the force of winding the toner around the fixing belt 603 . Therefore, the paper P on which the toner is fixed is discharged from the nip portion 251 in a state where the leading end portion is separated from the fixing belt 603 . In order to pick up the margin and separate the sheet P from the fixing belt 603, the tip of the non-contact separating plate 62 is arranged near the exit of the nip portion with a gap of 0.05 to 0.5 mm from the fixing belt 603. It is

On the other hand, for example, when forming images on both sides of the paper P, the toner fixed on the first surface of the paper P is softened by the pressure member 61 and separated from the pressure member 61 during image formation on the second surface. may worsen sex. For this reason, the fixing unit 25 includes a pressure separating claw unit 63 that contacts the pressure member 61 and separates the sheet P from the pressure member 61 . Further, in order to assist separation by the pressurizing separation claw unit 63, the image is formed so that a margin is provided at the rear end of the first surface, which is the leading end of the second surface. As a result, the paper P can be conveyed satisfactorily even in double-sided image formation.

The pressure separation claw unit 63 includes a positioning plate 631, a first spring 632, a pressure separation claw 633, a separation stay 634, a second spring 635, a stopper 636, an adjustment mechanism 637, and a transmission member 638. have The pressure separating claw unit 63 is provided so as to be able to contact and separate from the pressure member 61 .

The tip portion of the positioning plate 631 is always in contact with the non-sheet-passing portion of the outer periphery of the pressing member 61 due to the biasing force of the first spring 632 .

The pressure separation claw 633 is provided on a separation stay 634 that can swing independently of the positioning plate 631 . The pressure separating claw 633 is positioned downstream of the nip portion in the direction in which the paper P is conveyed. The separation stay 634 is a long member whose longitudinal direction is the axial direction of the pressure member 61 . A pressure separation claw 633 is attached to the separation stay 634 . The separation stay 634 is stopped by contacting a stopper 636 provided on the opposite side of the pressure member 61 with the separation stay 634 interposed therebetween, while being urged by the second spring 635 in the direction away from the pressure member 61 . is doing.

The adjustment mechanism 637 adjusts the pressure separation claw 633 so that the distance between the tip portion of the pressure separation claw 633 and the surface of the pressure member 61 is a predetermined distance while the separation stay 634 is in contact with the stopper 636 . Adjust position. The adjustment mechanism 637 is a feed mechanism that advances and retreats the pressure separation claw 633 toward the pressure member 61 by rotating a screw, for example.

For example, in a state in which the pressure separation claw 633 is separated from the pressure member 61 , the paper P may be passed between the tip portion of the pressure separation claw 633 and the surface of the pressure member 61 . In this case, if the distance between the tip of the pressurizing separation claw 633 and the surface of the pressure member 61 is too wide or too narrow, the passing paper P may be pushed to the tip of the pressurizing and separating claw 633 or the pressure member. 61, and the paper may not be fed properly.

With the separation stay 634 in contact with the stopper 636, the adjustment mechanism 637 maintains a predetermined distance between the tip of the pressure separation claw 633 and the surface of the pressure member 61, thereby improving the above-described paper passing. can be done.

The transmission member 638 is in contact with or connected to the cleaning unit 64 and the pressure member 41 in order to bring the pressure separating claw unit 63 and the cleaning unit 64 into contact with each other. It is a member that transmits the force of contacting and separating to the pressurizing separation claw unit 63 . The transmission member 638 is, for example, a metal leaf spring having one end attached to the pressure separating claw unit 63 and the other end contacting the cleaning unit 64 .

When the cleaning unit 64 approaches the pressing member 61 , the cleaning unit 64 pushes the transmission member 638 . This pushing force is applied to the pressure separating claw unit 63 via the transmission member 638 . As a result, in conjunction with the movement of the cleaning unit 64 approaching the pressure member 61 , the pressure separation claw unit 63 can be brought closer to the pressure member 61 and the pressure separation claw 633 can be brought into contact with the pressure member 61 . .

On the other hand, when the cleaning unit 64 moves away from the pressure member 61 , the force pushing the transmission member 638 weakens according to the movement of the cleaning unit 64 . As a result, the pressure separation claw unit 63 can be moved away from the pressure member 61 and the pressure separation claw 633 can be separated from the pressure member 61 in conjunction with the movement of the cleaning unit 64 away from the pressure member 61 .

Since the pressure separation claw unit 63 is arranged near the exit of the nip portion 251, a small amount of residual toner generated by fixing may adhere to and accumulate on the pressure separation claw 633 provided in the pressure separation claw unit 63. . The toner accumulated in this manner is peeled off from the pressure separation claw 633 by switching between the rotation and stop of the pressure member 61 and the impact of pressure contact and separation to the pressure member 61 , and passes through the pressure member 61 to the next image. It may be transferred to the paper on which it is formed.

The fixing unit 25 is equipped with a cleaning unit 64 that cleans the surface of the pressure member 61 in order to prevent the toner separated from the pressure separating claw 633 from being transferred to the next sheet on which an image is to be formed.

The cleaning unit 64 has a web supply roller 641 , a web pressing roller 642 and a web take-up roller 643 . The cleaning unit 64 is provided so as to be able to come into contact with and separate from the pressure member 61 .

A spring (not shown) applies a biasing force to the web pressing roller 642 to press the web against the pressure member 61 . The web cleans residual toner on the surface of the pressure member 61 and toner separated from the pressure separation claw 633 . A new web is supplied from the web supply roller 641 by rotating the web take-up roller 643 at predetermined intervals. The cleaning unit 64 is an example of a "cleaning section".

The contact/separation drive mechanism 65 is a mechanism for bringing the cleaning unit 64 into contact with the pressure member 61 and separating it from the pressure member 61 . The contact/separation drive mechanism 65 includes, for example, an eccentric roller. When the eccentric roller is rotated and a portion of the eccentric roller with a long distance from the rotation axis to the outer periphery contacts the cleaning unit 64 , the cleaning unit 64 is pushed by the eccentric roller and contacts the pressure member 61 . Also, when the portion of the eccentric roller whose distance from the rotating shaft to the outer peripheral portion is short contacts the cleaning unit 64 , the cleaning unit 64 is separated from the pressing member 61 .

For example, a motor (not shown) is attached to the eccentric roller, and by controlling the rotation of the eccentric roller with the motor, it is possible to control the contact and separation of the cleaning unit 64 from the pressure member 61 .

As shown in FIG. 2 , when the cleaning unit 64 abuts against the pressure member 61 , the cleaning unit 64 is pushed toward the pressure member 61 by the contact/separation drive mechanism 65 . The separation stay 634 receives force in the direction of contacting the pressure member 61 due to the action of the transmission member 638, and this force exceeds the force of the second spring 635 applied in the direction away from the pressure member 61, so that the pressure is applied. Separation claw 633 contacts pressing member 61 .

On the other hand, FIG. 3 is a diagram showing a case where the cleaning unit 64 is separated from the pressing member 61. As shown in FIG. As shown in FIG. 3, when the cleaning unit 64 moves away from the pressure member 61, the force with which the separation stay 634 is pushed by the transmission member 638 weakens. When this force exceeds the force of the second spring 635 applied in the direction away from the pressure member 61 , the pressure separation claw 633 is separated from the pressure member 61 . The separation stay 634 contacts the stopper 636 to maintain a predetermined gap between the tip portion of the pressure separation claw 633 and the surface of the pressure member 61 .

FIG. 4 is a diagram showing the relationship between the amount of bite of the cleaning unit 64 into the pressure member 61 and the biasing force of the pressure separation claw 633 to the pressure member 61 . In FIG. 4 , the horizontal axis indicates the biting amount R when the cleaning unit 64 is pushed by the contact/separation drive mechanism 65 and comes into contact with the pressure member 61 . Incidentally, the “bite amount” is the amount by which the surface of the pressure member 61 is pushed by the cleaning unit 64 and bites inward.

The vertical axis of FIG. 4 represents the difference between the force with which the separation stay 634 is pushed toward the pressure member 61 by the transmission member 638 and the force of the second spring 635 applied in the direction away from the pressure member 61 . there is Such a force difference is called a contact/separation force Q. As shown in FIG.

In FIG. 4 , a range 71 indicates a range in which the contact/separation force Q has a positive value, in other words, indicates a range of the contact/separation force Q at which the pressure separation claw 633 contacts the pressure member 61 . A range 72 indicates a range in which the contact/separation force Q has a negative value, in other words, indicates a range of the contact/separation force Q in which the pressure separation claw 633 separates from the pressure member 61 .

A biting amount 74 indicates the maximum value of the biting amount R. A range 73 indicates a range in which the biting amount R is 0 or more and the maximum biting amount 74 or less.

A range 75 indicates a state in which the pressure separation claw 633 contacts the pressure member 61 and a state in which the pressure separation claw 633 contacts the pressure member 61 in the range 73 of the biting amount R in which the cleaning unit 64 contacts the pressure member 61 . It shows the range of the contact/separation force Q that can be realized by switching between the separated states.

When the cleaning unit 64 approaches the pressure member 61 by being pushed by the contact/separation drive mechanism 65, the force with which the separation stay 634 is pushed by the transmission member 638 increases. In a state where the amount R of the cleaning unit 64 biting into the pressure member 61 is 0 or more (a state in which the cleaning unit 64 is in contact with the pressure member 61), the force with which the separation stay 634 is pushed by the transmission member 638 is A transmission member 638 is arranged so that the force of the second spring 635 is greater. For example, in FIG. 4, the position where the transmission member 638 is provided is determined so that the contact/separation force Q falls within the range indicated by the range 75 . The position where the transmission member 638 is provided may be determined, for example, at the stage of designing the fixing unit 25 .

By doing so, when the pressure separation claw 633 contacts the pressure member 61, the pressure separation claw 633 contacts the pressure member 61 before the pressure separation claw 633 contacts the pressure member 61, or the pressure separation claw 633 The cleaning unit 64 can be brought into contact with the pressure member 61 simultaneously with the contact with the pressure member 61 . Further, when the pressure separation claw 633 is separated from the pressure member 61 , at the same time as the pressure separation claw 633 is separated from the pressure member 61 or before the pressure separation claw 633 is separated from the pressure member 61 . The cleaning unit 64 can be separated from the pressure member 61 later.

Even if there is a foreign matter such as a clump of residual toner at the tip of the pressure separation claw 633 , the cleaning unit 64 always contacts the pressure member 61 when the pressure separation claw 633 contacts the pressure member 61 . ing. Also, when the pressure separation claw 633 is separated from the pressure member 61 , the cleaning unit 64 is always in contact with the pressure member 61 . Therefore, even if foreign matter is peeled off from the tip of the pressurizing separation claw 633 and dropped, it can be reliably collected by the cleaning unit 64 .

As described above, in the present embodiment, the pressure separation claw 633 contacts and separates from the pressure member 61 at a timing that is interlocked with the contact and separation of the cleaning unit 64 with respect to the pressure member 61 . As a result, the cleaning unit 64 can reliably collect the foreign matter accumulated on the pressurizing separation claw 633 . In addition, it is possible to prevent the occurrence of an abnormal image due to foreign matter adhering to the paper P.

[Second embodiment]
Next, an example of an image forming apparatus according to the second embodiment will be described. Note that the description of the same components as those of the already described embodiment will be omitted.

In this embodiment, a plurality of pressurizing separation claws 633 are attached at different positions in the longitudinal direction of the separation stay 634 . Further, an adjustment mechanism 637 is provided for each of the plurality of pressure separation claws 633 to enable adjustment of the distance between the tip portion of the pressure separation claw 633 and the surface of the pressure member 61 for each pressure separation claw 633 .

As a result, for example, in a state in which the pressure separation claw 633 is separated from the pressure member 61, the paper P can be smoothly passed between the front end portion of the pressure separation claw 633 and the surface of the pressure member 61. be able to.

Effects other than the above are the same as those described in the first embodiment.

Although the fixing device and the image forming apparatus according to the embodiments have been described above, the present invention is not limited to the above embodiments, and various modifications and improvements are possible within the scope of the present invention.

100 image forming device 25 fixing unit (an example of fixing device)
251 nip portion 60 fixing member 601 fixing roller 602 heating roller 603 fixing belt 604 heater (an example of a heating portion)
61 pressure member 62 non-contact separation plate 63 pressure separation claw unit 631 positioning plate 632 first spring 633 pressure separation claw 634 separation stay 635 second spring 636 stopper 637 adjustment mechanism 638 transmission member 64 cleaning unit (an example of the cleaning section )
641 Web supply roller 642 Web pressing roller 643 Web take-up roller 65 Contact/separation drive mechanism 71 Contact/separation force range 72 where the pressure/separation claw contacts the pressure member Range of force 73 Range of biting amount in which the cleaning unit abuts against the pressure member 74 Maximum value of biting amount 75 Range of contact/separation force capable of realizing contact/separation between the pressure separation claw and the pressure member

JP-A-01-040870

Claims (6)

a fixing member heated by a heating unit;
a pressing member arranged to press at least part of the fixing member and forming a nip portion with the fixing member;
a cleaning unit having a cleaning part provided to be contactable and separable with respect to the pressure member;
a pressure separation claw provided to be able to contact and separate from the pressure member; a separation stay to which the pressure separation claw is attached; a spring that applies force to the separation stay in a direction away from the pressure member; a pressurized separation claw unit having
The pressurizing separation claw unit is further provided with one end of a transmission member that is a member that transmits the force of the cleaning unit contacting and separating from the pressurizing member to the pressurizing separation claw unit,
the other end of the transmission member contacts the cleaning unit;
The pressure separation claw is separated from the pressure member at the same time as or earlier than the timing at which the cleaning portion separates from the pressure member, and at the timing at which the cleaning portion contacts the pressure member. At the same time as or after the timing, contacting the pressure member,
The transmission member is arranged such that the force with which the separation stay is pushed by the transmission member when the cleaning unit is in contact with the pressure member is greater than the force of the spring , and the cleaning unit is pressurized by the pressure member. A fixing device , wherein the separation stay is arranged so that the force of the separation stay being pushed by the transmission member is smaller than the force of the spring when the separation stay is separated from the member. The fixing device is
fixing the unfixed toner image on a recording medium carrying the unfixed toner image and conveyed to the nip portion;
2. The fixing device according to claim 1, wherein the pressure separation claw is positioned downstream of the nip portion in the direction in which the recording medium is conveyed. 3. The fixing device according to claim 1, further comprising an adjusting mechanism for adjusting a gap between said pressure separation claw and said pressure member. The fixing device has a plurality of separation claws,
4. The fixing device according to claim 3, wherein the adjustment mechanism is provided for each pressure separating claw. 5. The fixing device according to claim 3, wherein the adjusting mechanism separates the pressure separation claw and the pressure member at a predetermined distance. An image forming apparatus comprising the fixing device according to claim 1 .

Images