JPH11352820A - Fixing device and image forming device provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the rotation of a fixing body to be forcibly stopped with inexpensive and simple structure by providing a device with a stop means which can forcibly stop the rotation of the fixing body. SOLUTION: The fixing device 18 is constituted by being provided with a fixing roller 18a, a pressure roller made to press-contact with the roller 18a, a motor 27 driving the roller 18a to be rotated by giving rotational force to it and a torque limiter 62 obstructing the rotation of the roller 18a. Besides, it is provided with a fixing clutch 35 transmitting the rotational force to the roller 18a from the motor 27 or cutting off it and a rotational force transmission device 61 transmitting force for obstructing the rotation of the roller 18a to the roller 18a from the limiter 62 or cutting off it in response to the on/off state of the clutch 35. When abnormality such as jamming is detected at a fixing part by a sensor, the clutch 35 becomes the off-state and the transmission device 61 becomes an on-state. Then, the torque of the limiter 62 is transmitted to a rotary shaft 32 through gears G11-G7 so as to forcibly stop the rotation of the roller 18a and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art In a conventional fixing device, the size of an image forming apparatus is reduced, so that when a transfer material as a recording medium enters the fixing device, the transfer material vibrates due to the impact. However, at that time, since the rear end of the transfer material does not pass through the transfer charger, transfer deviation may occur. In order to prevent this, a fixing device is disclosed in
As described in Japanese Patent No. 1008, as a means for maintaining a constant peripheral speed of a fixing roller as a fixing body and improving image quality, a control member having a large inertia force such as a flywheel is used. Known and in practical use.

In this fixing device 118, as shown in FIG. 10, a flywheel 133 and a gear G106 are fixed on a rotating shaft 132, and the rotation of the fixing roller 118a is controlled by a flywheel via gears G105, G106 and the shaft 132. The signal is transmitted to the wheel 133.

[0004] The fixing roller 118a is used to stop the copying operation or at the time of jam (transfer material P stays) at the fixing section (the pressure contact section between the fixing roller 118a and the pressure roller 118b).
When the fixing clutch (not shown) is turned off, the drive transmission of the electric motor (not shown) is released, and the fixing roller 118 is turned off.
a The motor stops while naturally decelerating due to its own rotational resistance.

[0005]

However, in such a fixing device 118, the inertia force of the flywheel 133 is large because the fixing device 118 is configured to stop while naturally decelerating due to the rotational resistance of the fixing roller itself. And the stopping distance becomes longer.

Thus, for example, the tip 1 of the separation claw 144
At 44b, when the transfer material P is jammed, the fixing roller 118a continues to rotate due to the inertial force even when the driving to the fixing roller 118a is released.
There is a possibility that a problem such as breakage of the roller may occur due to the claw 144 being pressed by the transfer material P in the rotation direction of the roller 18b.

Further, the transfer material P that has been jammed in the fixing device 118 is caught inward by the rotation of the fixing roller 118a and enters the inside of the machine due to tears of the transfer material and the like, and the jam is removed (removed transfer material is removed). thing)
May be impossible.

[0008] In recent years, as the size of the image forming apparatus is reduced and more stable image quality is required, the use of a large control member is inevitable in order to keep the peripheral speed of the fixing roller constant.
When the transfer material stays in the fixing device, the above-described problem may be further increased.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fixing device which is inexpensive and has a simple structure and can forcibly stop the rotation of a fixing member, and an image forming apparatus provided with the fixing device.

[0010]

According to the present invention, an object of the present invention is to provide a method for fixing an unfixed image on a recording medium by a rotatable fixing member for applying heat and pressure to the unfixed image carried on the recording medium. This is achieved by the first invention in which the fixing device for fixing the image on the top has a stopping means capable of forcibly stopping the rotation of the fixing body.

Further, according to the present application, the above object is achieved in the first aspect by the interlocking means for forcibly stopping the rotation of the fixing member when the recording medium stays in the fixing device. This is also achieved by the second invention of having.

Further, according to the present application, the above object is achieved according to the second invention in that the interlocking means forcibly stops the rotation of the fixing body when the driving means for driving the fixing body disconnects the driving force connection. The invention is also achieved by the third invention that is designed to cause the above.

According to the present application, the above object is achieved by any one of the first to third inventions, wherein the stopping means comprises:
The present invention is also achieved by the fourth invention having a friction member for preventing rotation of the fixing member by frictional force.

Further, according to the present application, the above object is as set forth in any one of the first to third inventions, wherein the stopping means has a magnetic member for preventing rotation of the fixing member by a magnetic force. This is also achieved by the fifth invention.

Further, according to the present application, the above object is achieved in any one of the second to fifth inventions by the following:
The present invention is also achieved by the sixth invention in which a frictional force or a magnetic force for stopping rotation of the fixing body can be transmitted to the fixing body.

Further, according to the present application, the above object is to provide an image forming apparatus for recording image information formed by a series of image forming processes on a recording medium, comprising a fixing device according to the first invention. This is also achieved by the seventh invention.

Further, according to the present application, the above object is achieved according to the seventh aspect, wherein the stopping means comprises an interlocking means for forcibly stopping the rotation of the fixing member when the recording medium stays in the fixing device. The invention is also achieved by the eighth invention having the above.

Further, according to the present application, the above object is achieved according to the eighth invention in that the interlocking means forcibly stops the rotation of the fixing body when the driving means for driving the fixing body disconnects the driving force connection. The present invention is also achieved by a ninth aspect of the invention.

According to the present application, the above object is achieved by any one of the seventh to ninth aspects,
The present invention is also achieved by a tenth aspect in which a friction member that prevents rotation of the fixing member by frictional force is provided.

Further, according to the present application, the above object is as set forth in any one of the seventh to ninth aspects, wherein the stopping means has a magnetic member for preventing rotation of the fixing member by a magnetic force. This is also achieved by the eleventh invention.

Further, according to the present application, the above object is achieved in any one of the eighth to eleventh inventions, wherein the interlocking means transmits a frictional force or a magnetic force for stopping rotation of the fixing body to the fixing body. It is also achieved by a twelfth invention that is possible.

That is, in the first invention according to the present application, the stopping means forcibly stops the rotation of the fixing body.

According to the second invention of the present application, when the recording medium stays in the fixing device, the interlocking means provided in the stopping means forcibly stops the rotation of the fixing body. .

Further, in the third invention according to the present application, when the driving means for rotating and driving the fixing body releases the connection of the driving force, the interlocking means provided in the stopping means is provided with the interlocking means for the fixing body. Stop the rotation forcibly.

In the fourth aspect of the present invention, the stopping means forcibly stops the rotation of the fixing member by the frictional force of the friction member.

Further, in the fifth invention according to the present application, the stopping means forcibly stops the rotation of the fixing member by the magnetic force of the magnetic member.

In the sixth aspect of the present invention, the interlocking means provided in the stopping means forcibly stops the rotation of the fixing body by transmitting a frictional force or a magnetic force to the fixing body. Let it.

Further, in the seventh invention according to the present application, the stopping means forcibly stops the rotation of the fixing member.

According to the eighth aspect of the present invention, when the recording medium stays in the fixing device, the interlocking means provided in the stopping means forcibly stops the rotation of the fixing body. .

Further, according to the ninth invention of the present application, when the driving means for rotating and driving the fixing body releases the connection of the driving force, the interlocking means provided in the stopping means is provided with the fixing means. Stop the rotation forcibly.

According to the tenth aspect of the present invention, the stopping means forcibly stops the rotation of the fixing member by the frictional force of the friction member.

Further, in the eleventh invention according to the present application, the stopping means forcibly stops the rotation of the fixing member by the magnetic force of the magnetic member.

In the twelfth invention according to the present application, the interlocking means provided in the stopping means forcibly rotates the fixing body by transmitting frictional force or magnetic force to the fixing body. Stop.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. 1 to 9 of the accompanying drawings.

(First Embodiment) First, an electrophotographic copying machine as an example of an image forming apparatus according to a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a sectional view showing a schematic configuration of an image forming apparatus according to the present embodiment, FIG. 2 is a sectional view showing a schematic configuration of a main part of the image forming apparatus of FIG. 1, and FIG. FIG. 2 is a top view illustrating a schematic configuration of a fixing device provided in the image forming apparatus of FIG. 1.

As shown in FIG. 1, the copying machine includes a drum-shaped photosensitive drum 1 on which an electrostatic latent image is formed on an outer peripheral surface.
A roller-shaped primary charger 2 for charging the outer peripheral surface of the photosensitive drum 1 to a specified potential; an optical system 20 for forming an electrostatic latent image on the outer peripheral surface charged to the specified potential by exposure;
21, 22, 23, 24, 25, 26, 50, a developing device 3 for converting the electrostatic latent image into a visible image with a developer, and a visible image (visible image) formed on the outer peripheral surface in a sheet form. Roller-like transfer charger 4 for transferring to transfer material P as a recording medium
And a fixing device 18.

In such a copying machine, a photosensitive drum 1 as a latent image carrier is rotatably supported in a main body 10 of the copying machine, and a primary charger 2, a developing device 3, Process devices such as a transfer charger 4, a separation charger 5, and a cleaner 6 are provided.

A toner hopper 7 for replenishing toner as a developer is provided above the developing device 3. A plurality of transfer materials P are provided on one side (right side in FIG. 3) of the apparatus main body 10. Paper cassettes 11, 12,
13 and 14 are provided over the upper and lower four stages.

The transfer material P supplied from each of the paper feed cassettes 11, 12, 13, and 14 is conveyed in the apparatus body 10 in the direction of the arrow shown in FIG. The pressure roller 18b includes a transport device 16, a pre-fixing guide 17, a fixing roller 18a serving as a fixing member, and a pressure roller 18b. The pressure roller 18b has a surface layer made of an elastic material.

On the other hand, a lamp 20 constituting an optical system, reflection mirrors 21 to 26, an optical lens 50, and the like are arranged in an upper portion in the apparatus main body 10. The original 51 set on the original mounting table 301 provided on the upper surface of the apparatus main body 10 is read by an optical system, and when a light image corresponding to the original is exposed on the photosensitive drum 1, the primary charger An electrostatic latent image is formed on the photosensitive drum 1 whose surface is charged by 2, and the electrostatic latent image is developed by the developing device 3 and visualized as a toner image.

On the other hand, a transfer material P is supplied from, for example, a paper feed cassette 11, and the transfer material P is sent to a transfer portion between the photosensitive drum 1 and the transfer charger 4 at the same timing by the registration roller 15, and is exposed to light. The transfer of the toner image formed on the drum 1 is superimposed, and then the toner image is separated from the photosensitive drum 1 by the operation of the separation charger 5.

Then, the transfer material P separated from the photosensitive drum 1 is sent to the fixing device 18 by the belt conveying device 16, and the fixing roller 18a of the fixing device 18 and the pressing roller 1
8b, the toner image is fixed by heat and pressure by passing therethrough, and then discharged out of the apparatus main body 10 by the discharge roller 19.

Next, regarding the schematic structure of the fixing device 18,
A description will be given based on FIG. 2 and FIG.

The fixing roller 18 includes a rotatable fixing roller 18a and a pressure roller 18 which is in pressure contact with the fixing roller 18a.
b, an electric motor 27 as driving means for applying a rotational force to the fixing roller 18a to rotate the fixing roller 18a, a rotational force limiting member 62 as a stopping means for preventing rotation of the fixing roller 18a, and rotation from the electric motor 27 to the fixing roller 18a. A fixing clutch 35 that transmits or interrupts (ON / OFF) a force, and transmits or interrupts a force that inhibits rotation of the fixing roller 18a from the rotational force limiting member to the fixing roller 18a according to ON / OFF of the fixing clutch 35. (ON / OFF).

Fixing roller 18 provided in fixing device 18
a is, as shown in FIG. 2, between a pulley 28 that is driven to rotate by the electric motor 27 and is connected to an output shaft end of the electric motor 27 and a pulley 30 that is connected to one end of the rotating shaft 29. An endless drive belt 31 is wound.

A gear G1 is connected to the other end of the rotating shaft 29. A gear G4 is connected to one end of the rotating shaft 18a-1 of the fixing roller 18a. Gear G2.

When the fixing clutch 35 is turned on, the drive of the gear G2 is transmitted to the gear G3 to rotate the gear G4 meshed with the gear G3.

A large-diameter gear G5 is connected to the other end of the rotating shaft 18a-1 of the fixing roller 18a.
The gear meshes with a small-diameter gear G <b> 6 attached to the rotation shaft 32.

A flywheel 33 and a gear G7 are connected to the free end of the rotary shaft 32, and a gear G9 is connected to one end of the rotary shaft 65. A gear G10 is connected to the electromagnetic clutch 61 and the other end.

The gear G10 meshes with a gear G11 connected to one end of the rotating shaft 65. The rotation of the gear G <b> 11 also rotates the shaft 65, and the torque of a torque limiting member (hereinafter, referred to as a torque limiter) 62 fixed to the support plate 63 is applied to the shaft 65.

When the image forming operation is started, the electric motor 27 is driven.
The power is transmitted to the rotating shaft 29 via the drive belt 31 and the pulley 30.

The rotation of the rotating shaft 29 is transmitted to the gear G3 when the gears G1 and G2 and the fixing clutch 35 are turned on, and further transmitted to the fixing roller 18a via the gear G4 to rotate the fixing roller 18a at a predetermined speed. It is driven and used for fixing the toner image described above.

The rotation of the fixing roller 18a is performed by the gears G5 and G6.
Is transmitted to the rotating shaft 32 and further transmitted to the gears G7, G8 and G9, but the electromagnetic clutch 61 is OFF and is not transmitted after G10.

The rotating shaft 32 and the flywheel 33 connected thereto are driven to rotate at a higher speed than the fixing roller 18a.
Since the inertia force of 8a is increased and the peripheral speed is kept constant,
The occurrence of image disturbance due to transfer deviation is suppressed, and a high-quality image can always be obtained stably.

Next, the transfer material P on which the image has been fixed is separated from the separation claw 4 which is normally rotatable about the shaft portions 43a and 44a.
The sheet is separated from the fixing roller by the rollers 44, and is discharged through the jam detection sensor flag 40. When the fixing clutch 35 is turned off, the fixing roller 18a and the flywheel 33 decelerate and stop while rotating by inertia.

However, when the sensor 41 detects an abnormality such as a jam in the fixing unit, the fixing clutch 35 is turned off and the electromagnetic clutch 61 is turned on at the same time, and the torque of the torque limiter 62 is transmitted via the gears G11 to G7. , The rotation shaft 32 is transmitted. Therefore, the rotation of the fixing roller 18a and the flywheel 33 can be forcibly stopped in a short time.

As a result, as shown in FIG.
Even when the transfer material P causes a nail jam at the leading end 44b, it is possible to prevent the roller 44 from being damaged or damaged due to the claw 44 being pressed by the transfer material P in the rotation direction of the pressure roller 18b. Further, the transfer material P having caused the jam is caught inside by the rotation of the roller,
It is possible to prevent the jam from being removed due to a break or the like.

Therefore, according to the present embodiment, since the torque limiter 62 forcibly stops the rotation of the fixing roller 18a, when the transfer material P stays in the fixing device 18, the fixing is performed. It is possible to prevent the transfer material P from being wound around the roller 18a and prevent the fixing roller 18a from being damaged.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 3 is a top view schematically illustrating a configuration of a fixing device provided in the image forming apparatus according to the present embodiment. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. I do.

In this embodiment, the electromagnetic clutch 6
1 and a torque limiter 62,
Also in this case, when the sensor 41 detects an abnormality such as a jam in the fixing unit, the electromagnetic clutch 61 is simultaneously turned on,
Torque limiter 62 attached to output rotary plate 70
With this torque, the rotation of the fixing roller 18a and the flywheel 33 can be forcibly stopped in a short time with a simpler configuration.

Therefore, according to the present embodiment, since the torque limiter 62 forcibly stops the rotation of the fixing roller 18a, when the transfer material P stays in the fixing device 18, the fixing is performed. It is possible to prevent the transfer material P from being wound around the roller 18a and prevent the fixing roller 18a from being damaged.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 1 is a top view schematically illustrating a configuration of a fixing device provided in an image forming apparatus according to the present embodiment. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. .

In this embodiment, the structure after the gear G9 in FIG. 2 is meshed with the gear G4. If the space is limited before the fixing unit due to the configuration, it can be attached to the drive side. Also in this case, when an abnormality such as a jam in the fixing unit is detected by the sensor, the electromagnetic clutch 61 is simultaneously turned on and the torque limiter 62 is turned on.
With this torque, the rotation of the fixing roller 18a and the flywheel 33 can be forcibly stopped in a short time.

Therefore, according to the present embodiment, the torque limiter 62 forcibly stops the rotation of the fixing roller 18a. Therefore, when the transfer material P stays in the fixing device 18, the fixing is performed. It is possible to prevent the transfer material P from being wound around the roller 18a and prevent the fixing roller 18a from being damaged.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to FIG. Note that FIG.
FIG. 2 is a top view schematically illustrating the configuration of a fixing device provided in the image forming apparatus according to the present embodiment. The same reference numerals are given to the same components as in the first embodiment, and description thereof is omitted. .

In this embodiment, the outer periphery of the flywheel 80 is gear-shaped. In this case, when an abnormality such as a jam in the fixing portion is detected by a sensor, the electromagnetic clutch 61 is simultaneously turned on and the torque limiter is turned on. With the torque of 62, a load is applied to the outer periphery of the flywheel 33, whereby the rotation of the fixing roller 18a can be forcibly stopped in a short time.

Therefore, according to the present embodiment, the torque limiter 62 forcibly stops the rotation of the fixing roller 18a. Therefore, when the transfer material P stays in the fixing device 18, the fixing is performed. It is possible to prevent the transfer material P from being wound around the roller 18a and prevent the fixing roller 18a from being damaged.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 2 is a top view schematically illustrating the configuration of a fixing device provided in the image forming apparatus according to the present embodiment. The same reference numerals are given to the same P configurations as in the first embodiment, and description thereof is omitted. I do.

In this embodiment, a friction plate 90 serving as a first friction member is fixed on a shaft 32, and a rotatable arm 93 is rotated about a shaft 95 by the operation of a suction device 97, so that the shaft 93 is rotated. By pressing the second friction plate 91 fixed on the second friction plate 92 against the first friction plate 90, a torque is applied to the shaft 32, thereby forcibly stopping the rotation of the fixing roller 18a in a short time. I have.

Therefore, according to the present embodiment, the friction plate 90
However, since the rotation of the fixing roller 18a is forcibly stopped, when the transfer material P stays in the fixing device 18, the transfer material P is wound around the fixing roller 18a or the fixing roller 18a is damaged. Etc. can be prevented.

(Sixth Embodiment) Next, a sixth embodiment of the present invention will be described with reference to FIG. Note that FIG.
FIG. 1 is a top view schematically illustrating a configuration of a fixing device provided in an image forming apparatus according to the present embodiment. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. .

In this embodiment, instead of the torque limiter 62 shown in the first embodiment, a magnetic member 201 constituted by a magnet is arranged on a shaft 65. When the sensor 41 detects an abnormality such as a jam at the time, the electromagnetic clutch 61 is turned on at the same time, and the magnetic force of the member 201 acts on the shaft 65 to cause rotational resistance. Is transmitted to the rotating shaft 32 via the. Therefore, the fixing roller 18a
In addition, the rotation of the flywheel 33 can be forcibly stopped in a short time.

Therefore, according to the present embodiment, the magnetic member 2
01 forcibly stops the rotation of the fixing roller 18a, so that when the transfer material P stays in the fixing device 18, the transfer material P is wound around the fixing roller 18a or the fixing roller 18a Breakage and the like can be prevented.

[0075]

As described above, according to the first aspect of the present invention, the stopping means forcibly stops the rotation of the fixing member. When the recording medium stays, it is possible to prevent the recording medium from being entangled in the fixing body, breakage of the fixing body, and the like.

According to the second invention of the present application,
When the recording medium stays in the fixing device, the interlocking means provided in the stopping means forcibly stops the rotation of the fixing body, so that the frequency of using the stopping means is reduced,
The inexpensive and simple structure that is not necessary for obtaining the durability of the stopping means can prevent the recording medium from being caught in the fixing body and the fixing body from being damaged when the recording medium stays in the fixing device. .

Further, according to the third aspect of the present invention, when the driving means for driving the fixing body to rotate is released from the connection of the driving force, the interlocking means provided in the stopping means is used to rotate the fixing body. Is forcibly stopped, so
Reducing the load of the driving force from the driving means on the stopping means,
The inexpensive and simple structure that is not necessary for obtaining the durability of the stopping means can prevent the recording medium from being caught in the fixing body and the fixing body from being damaged when the recording medium stays in the fixing device. .

According to the fourth invention of the present application,
Since the stopping means forcibly stops the rotation of the fixing member by the frictional force of the friction member, when the recording medium stays in the fixing device, the recording medium is wound around the fixing member or fixed. Body damage and the like can be prevented.

Further, according to the fifth aspect of the present invention, the stopping means forcibly stops the rotation of the fixing member by the magnetic force of the magnetic member. When the recording medium stays, it is possible to prevent the recording medium from being entangled in the fixing body, breakage of the fixing body, and the like.

According to the sixth aspect of the present invention,
The interlocking means provided in the stopping means forcibly stops the rotation of the fixing body by transmitting a frictional force or a magnetic force to the fixing body, so that the recording medium stays in the fixing device. In addition, it is possible to prevent the recording medium from being entangled in the fixing body and prevent the fixing body from being damaged.

Further, according to the seventh aspect of the present invention, since the stopping means forcibly stops the rotation of the fixing member, when the recording medium stays in the fixing device, It is possible to prevent the recording medium from being entangled in the fixing body and prevent the fixing body from being damaged.

According to the eighth invention of the present application,
When the recording medium stays in the fixing device, the interlocking means provided in the stopping means forcibly stops the rotation of the fixing body, so that the frequency of using the stopping means is reduced,
The inexpensive and simple structure that is not necessary for obtaining the durability of the stopping means can prevent the recording medium from being caught in the fixing body and the fixing body from being damaged when the recording medium stays in the fixing device. .

Further, according to the ninth aspect of the present invention, when the driving means for rotating and driving the fixing member releases the connection of the driving force, the interlocking means provided in the stopping means changes the rotation of the fixing member. Is forcibly stopped, so
Reducing the load of the driving force from the driving means on the stopping means,
The inexpensive and simple structure that is not necessary for obtaining the durability of the stopping means can prevent the recording medium from being caught in the fixing body and the fixing body from being damaged when the recording medium stays in the fixing device. .

According to the tenth aspect of the present invention,
Since the stopping means forcibly stops the rotation of the fixing member by the frictional force of the friction member, when the recording medium stays in the fixing device, the recording medium is wound around the fixing member or fixed. Body damage and the like can be prevented.

Further, according to the eleventh aspect of the present invention, the stopping means forcibly stops the rotation of the fixing member by the magnetic force of the magnetic member. When the medium stays, it is possible to prevent the recording medium from being entangled in the fixing body, damage to the fixing body, and the like.

According to the twelfth aspect of the present invention, the interlocking means provided in the stopping means forcibly stops the rotation of the fixing body by transmitting frictional force or magnetic force to the fixing body. Therefore, when the recording medium stays in the fixing device, it is possible to prevent the recording medium from being entangled in the fixing body, damage to the fixing body, and the like.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view illustrating a schematic configuration of a main part of the image forming apparatus of FIG.

FIG. 3 is a schematic top view showing a schematic configuration of a fixing device provided in the image forming apparatus of FIG. 1;

FIG. 4 is a schematic diagram illustrating a state when a jam occurs in a main part of the image forming apparatus according to the first embodiment.

FIG. 5 is a schematic top view illustrating a schematic configuration of a fixing device according to a second embodiment of the present invention.

FIG. 6 is a schematic top view illustrating a schematic configuration of a fixing device according to a third embodiment of the present invention.

FIG. 7 is a schematic top view illustrating a schematic configuration of a fixing device according to a fourth embodiment of the present invention.

FIG. 8 is a schematic top view showing a schematic configuration of a fixing device according to a fifth embodiment of the present invention.

FIG. 9 is a schematic top view illustrating a schematic configuration of a fixing device according to a sixth embodiment of the invention.

FIG. 10 is a schematic sectional view showing a schematic configuration of a main part of a conventional image forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Copier (image forming apparatus) 18a Fixing roller (fixing body) 18 Fixing apparatus 62 Torque limiter (stopping means) 27 Motor (driving means) 61 Rotary force transmission device (interlocking means) 90 Friction plate (friction member) 201 Magnetic member P transfer material (recording medium)

Claims (12)

[Claims] A fixing device for fixing the unfixed image on the recording medium by a rotatable fixing member for applying heat and pressure to the unfixed image carried on the recording medium; A fixing device, comprising: a stopping unit capable of temporarily stopping. 2. The fixing device according to claim 1, wherein the stopping unit includes an interlocking unit that forcibly stops the rotation of the fixing member when the recording medium stays in the fixing device. 3. The fixing device according to claim 2, wherein the interlocking means forcibly stops the rotation of the fixing member when the driving unit for driving the fixing member disconnects the driving force. apparatus. 4. The fixing device according to claim 1, wherein the stopping unit has a friction member that prevents rotation of the fixing member by a frictional force. 5. The fixing device according to claim 1, wherein the stopping unit has a magnetic member that prevents rotation of the fixing body by a magnetic force. 6. The fixing device according to claim 2, wherein the interlocking unit is capable of transmitting a frictional force or a magnetic force for stopping rotation of the fixing body to the fixing body. 7. An image forming apparatus for recording image information formed by a series of image forming processes on a recording medium, comprising the fixing device according to claim 1. 8. The image forming apparatus according to claim 7, wherein the stopping means includes an interlocking means for forcibly stopping the rotation of the fixing member when the recording medium stays in the image forming apparatus. 9. The image according to claim 8, wherein the interlocking means forcibly stops the rotation of the fixing body when the driving means for driving the fixing body disconnects the driving force. Forming equipment. 10. The image forming apparatus according to claim 7, wherein the stopping unit has a friction member that restricts a rotational force of the fixing member by a frictional force. 11. The stopping means has a magnetic member for limiting the rotational force of the fixing member by a magnetic force.
The image forming apparatus according to claim 9. 12. The image forming apparatus according to claim 8, wherein the interlocking unit is capable of transmitting a frictional force or a magnetic force for stopping rotation of the fixing body to the fixing body.