JPH0580615A - Transfer paper feeding device - Google Patents

Abstract

PURPOSE:To prevent image quantity from being deteriorated by adjusting the rotating speed of a feeding roller which is positioned in a feeding path for a transfer paper in accordance with the stretched state of the transfer paper. CONSTITUTION:The feeding roller positioned in the feeding path for the transfer paper, that is, the feeding roller positioned on a paper ejecting tray side constituting a paper ejecting part is provided in a state where it can link with driving rollers 16A and 17A. To put it concretely, the feeding roller is linked through a timing belt 24 which is laid between pulleys 23 attached to one-side ends in the axial direction of the supporting shafts 16A1 and 17A1 of the respective driving rollers 16A and 17A. Then, the driving gear 27 of a driving motor 26 is meshed with a driven fear 25 fixed on one supporting shaft 16A1. Meanwhile, the driving motor 26 is driven and controlled according to the signals of microswitches 21 and 22 for detecting the oscillation of a oscillating supporting member 19, so that the rotating speed of he feeding roller on the paper ejection part is made high when the transfer paper is in a slacked state, and the speed of the feeding roller on the paper ejection part side is made low when it is tense state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer paper conveying device.

[0002]

2. Description of the Related Art As is well known, in an image forming apparatus such as a copying machine, a visible image carried on a photoconductor or a transfer body is transferred onto a transfer paper such as plain paper to form a recorded image. To get. For this reason, the transfer paper on which the visible image is transferred from the photoconductor or the transfer body is conveyed to the fixing device and is discharged after the visible image is fixed.

[0003]

By the way, the above-mentioned transfer paper is conveyed by the sheet feeding device to the registration roller.
After the paper feed timing is set by the printer, it is performed on the path that passes through the transfer unit and the fixing device and is discharged, but since the transport speed on the above-described transport path is always set to the same speed, There were the following problems.

That is, the transfer rollers located after passing through the fixing device are arranged to be in contact with each other so that the transfer paper can be nipped and transferred. Alternatively, the coefficient of friction may change due to the evaporation of silicon oil used in the fixing device or the influence of ozone generated from the transfer unit, and the conveyance speed of the transfer paper that has passed through the fixing device is set to V1 until the fixing device is reached. If the conveying speed of V2 is V2, proper nipping and conveying cannot be performed due to the above-mentioned factors, and the relationship of V1 <V2, that is, the conveying speed of the transfer sheet that has passed through the fixing device becomes slower than the previous conveying speed. There is. Therefore, the transfer paper is loosened due to the change of the transfer speed in the transfer path. Especially, when a long transfer paper is used, the transfer paper is pulled so that it is rubbed against the transfer guide. Happened,
As a result, the image is rubbed and the image quality is deteriorated.

In response to such a situation, it may be possible to adjust the conveying speed to the speed after the change, but if the conveying speed to reach the fixing device is adjusted, the photosensitive member and this photosensitive member are adjusted. Since it is necessary to change the operation speed of an optical device, which is an electrostatic latent image forming unit, to the sheet feeding system that feeds the transfer sheet to the device, the control becomes extremely difficult.

Therefore, in view of the above-mentioned problems in the conventional transfer sheet conveying device, an object of the present invention is to solve the above-mentioned problem with the transfer sheet conveying device regardless of the change with time of the pair of conveying rollers located in the conveying route of the transfer sheet after passing through the fixing device. Another object of the present invention is to obtain a transfer paper transporting device having a structure capable of preventing the phenomenon of buckling and image rubbing due to occurrence of slack in the transfer paper.

[0007]

In order to achieve this object, the present invention discharges a sheet from a fixing device that heats and fixes a transfer sheet carrying an unfixed image transferred from an image carrier while being nipped and conveyed. And a pair of curved guide members facing each other across the transport path on the downstream side of the fixing device in the transport direction of the transfer paper. In a transfer paper transporting device that is arranged along the transport path and is composed of a pair of transport rollers that are opposed to each other across the transport path, in the transport roller, the back side of the image bearing surface of the transfer paper. Drive loca
And a driven roller which is disposed so as to be able to come into contact with and separate from the drive roller and is located on the image surface side of the transfer sheet, and the driven roller which is rotatably supported at a swing end. , A swing supporting member that is normally swingable by being brought into contact with the drive roller, and is disposed so as to face the other swing end of the swing supporting member. A means for detecting the amount of rocking of the rocking support member is connected to a transport roller located on the side of the paper discharge section in the transfer paper transport path, and rotated with respect to the transport roller located downstream of the fixing device. The means for changing the speed and the means for detecting the amount of rocking of the rocking support member are connected to the input side, and the means for changing the rotational speed are connected to the output side. Based on the detection signal from the transfer roller, depending on the spread state of the transfer paper, the transport roller on the side of the paper discharge section. It is characterized by comprising a control unit for changing the rotational speed.

Further, according to the present invention, the drive torque of the drive roller in the transport roller on the side of the discharge unit is set to the drive roller of the transport roller on the fixing device side in accordance with the spread state of the transfer sheet. The feature is that it is changed with respect to LA.

Further, the present invention is characterized in that the contact pressure of the driven roller with respect to the drive roller in the above-mentioned transport roller on the paper discharge section side is changed according to the spread state of the transfer paper. There is.

Further, the present invention is characterized in that the roller diameter of the drive roller in the above-mentioned transport roller on the paper discharge portion side is changed in accordance with the spread state of the transfer paper.

[0011]

According to the present invention, the transport speed between the transport roller on the fixing device side and the transport roller on the paper discharge portion side can be changed according to the spread state of the transfer paper.

[0012]

Embodiments of the present invention will be described in detail below with reference to FIGS.

FIG. 1 shows an example of a copying machine to which the transfer sheet conveying apparatus according to the embodiment of the present invention is applied. The copying machine is composed of an image reading section and an image writing section. In the figure, the image writing unit is shown. That is, the drum-shaped photoconductor 2 is provided inside the writing unit 1.
A charging device 3, an exposure optical device 4, a developing device 5, a transfer / separation device 6, and a cleaning device 7 are provided around the photosensitive drum 2 along the rotation direction indicated by an arrow. They are arranged respectively.

An electrostatic latent image is formed on the above-mentioned photosensitive drum 2 by being uniformly charged by the charging device 3 and then imagewise exposed by the exposure optical device 3, and this latent image is developed by the developing device. After the visible image processing by 5, the transfer sheet S is conveyed by a transfer / separation device 6 from a sheet feeding unit described later.
Is electrostatically transferred to.

On the other hand, to the transfer / separation device 6, the transfer paper is fed from the paper feeding section 8, and specifically, the roll 8A and the transfer paper fed from this roll. A sheet feeding cassette portion 8C provided with a plurality of stages of cutters 8B for cutting the sheet according to the document length, a feeding roller 8D for feeding the transfer sheet fed from each sheet feeding cassette, and a transfer sheet It is composed of a registration roller 8E for setting the paper feed timing. In the figure, reference numeral 8F
Indicates a manual paper feeding unit.

Further, at a position where the transfer paper separated after being transferred by the transfer / separation device 6 is moved, a fixing device 10 for sandwiching and fixing the transfer paper via a conveyor belt 9 is arranged. A discharge / conveyance path 11 is provided at a position where the transfer sheet passing through the fixing device 10 reaches.
As shown in FIG. 2, the above-described discharge / conveyance path 11 is a path from the fixing device 10 to the discharge tray 11A,
On the downstream side of the fixing device 10, a plurality of guide members 12, 13, 14 are arranged along the transfer paper conveyance direction,
The guide member 12 located on the downstream side of the fixing device 10 is a curved guide member.

Then, between the above-mentioned guide members, a transport roller 1 is provided which faces the transport route of the transfer paper and faces each other.
5, 16 and 17 are respectively arranged, and those transport rollers located on the back side of the image bearing surface of the transfer paper are drive rollers 15A, 16A and 17A, and face the image bearing surface. Driven rollers 15B, 16
B and 17B.

Of the above-mentioned transport rollers, the fixing device 10
The transport roller 15 located on the downstream side of the
B can be brought into and out of contact with the drive roller 15A. That is, the driven roller 15B described above is rotatably supported at one swing end of a swing support member 19 which is swingably supported by a fulcrum shaft 18 provided in a non-moving part (not shown). Normally, the drive roller 15 is driven by the urging force of the spring 20 applied between the swing support member 19 and the stationary portion.
It comes in contact with A.

On the other hand, as shown in FIG. 3, the other swing end of the swing support member 19 is provided with a spring 20 on one of the microswitches 21 and 22 forming a swing amount detecting means provided in the immovable portion. It is possible to face each other by receiving the urging force of this, and this state corresponds to the state where the transfer paper is relaxed as shown by the solid line in FIG.

The other 2 of the above-mentioned microswitches
When the other swing end of the swing support member 19 faces 2, the transfer sheet is stretched from the slack state by the tension when the transfer sheet is in the tension state, as shown by the chain double-dashed line in FIG. It is when it is pushed by changing to a state. Therefore, the swing support member 19 and the micro switch 2
Based on the correspondence with Nos. 1 and 22, the spread state of the transfer paper is detected.

By the way, the other transport rollers located on the above-mentioned transfer sheet transport path, in other words, the transport rollers 16 and 17 located on the side of the sheet discharge tray 11A forming the sheet discharge portion, are shown in FIG. As shown in FIG. 5, the drive rollers 16A and 17A are provided so as to be interlocked with each other.
The A and 17A shafts 16A1 and 17A1 can be interlocked via a timing belt 24 hung on a pulley 23 attached to one axial end of the shafts 16A1 and 17A1.

One of the above-mentioned support shafts 16A
1, a driven gear 25 is fixed to the driven gear 2.
A drive gear 27 fixed to the output shaft of the drive motor 26 is meshed with the drive gear 5.

The drive motor 26 described above is driven and controlled by a control unit 28, which will be described later, to change the rotational speed of the transport roller on the paper discharge unit side.

That is, the control unit 28, in FIG.
It is composed of a micro computer used for sequence control of the copying machine, and has micro switches 21, 2 for detecting the swing amount of the swing support member 19 on the input side thereof.
2 is connected to the output side, and the drive section of the drive motor 26 described above is connected to the output side. Control unit 28 described above
In this case, since the rocking support member 19 is actuated by the microswitches 21 and 22 depending on the spread state of the transfer paper,
At the time of inputting a signal from the micro switch 21, which corresponds to the transfer sheet being in a loose state, the transport roller 1 on the side of the sheet discharge section 1
The rotation speed (V2) of 6 and 17 is faster than the rotation speed (V1) of the transport roller 15 on the downstream side of the fixing device 10 (V1 <V2).
When the position of the drive motor 26 is set so that the signal is input from the micro switch 22 corresponding to when the transfer paper is in a tension state, the paper is discharged in the opposite manner to the above case. The rotation speed of the transport rollers 16 and 17 on the side of the unit is set to be slower than that of the transport roller 15 on the downstream side of the fixing device 10.
The position of the drive motor 26 is set as (V1> V2). Therefore, when the transfer sheet is in the loose state, the transport rollers 16 and 17 on the side of the sheet discharge portion are fixed to the fixing device 10.
When the transfer paper is rotated faster than the transfer roller 15 on the side, the transfer paper is pulled, the seat bending due to the loosening on the fixing device 10 side is prevented, and when the transfer paper is in a tensioned state, it is ejected. The transfer rollers 16 and 17 on the side of the paper unit rotate slower than the transfer rollers 15 on the side of the fixing device 10, so that the transfer paper is loosened and rubbing of the image on the transfer paper is prevented. ..

Since this embodiment has the above-mentioned structure,
The operation will be described with reference to the flowchart showing the operation of the control unit 28, which is as shown in FIG. That is, when a long transfer sheet is conveyed, the micro switches 21, 22 are
It is determined whether or not the micro switch 21 on the side corresponding to the loose state of the transfer paper is turned on.
As described above, the rotational speed of the drive motor 26 is increased, and whether the tension state of the transfer paper is set or not is determined by the setting of the rotational speed of the drive motor 26 according to the operating state of the microswitch 22. When the switch 22 is turned on, the rotation speed of the drive motor 26 is reduced to set the rotation speeds of the transport rollers 16 and 17 on the sheet discharge section side to the above-described states.

According to this embodiment, it is possible to prevent the seat bending due to the looseness of the transfer sheet by setting the rotation speed of the transport roller on the side of the sheet discharge section through the control of the drive motor, and further, the transfer is possible. Image rubbing due to paper tension can be prevented.

By the way, the driving torque may be changed instead of the rotation speed of the transport roller on the side of the paper discharge section. FIG. 7 shows a structure for changing the above-mentioned drive torque. Specifically, the torque can be variably transmitted to the support shaft 16A1 of one of the conveying rollers 16A on the sheet discharge portion side. A driven gear 25 is attached via an electromagnetic powder clutch 29 that can be driven, and the driven motor 25 is attached to the driven gear 25.
A drive gear 27 fixed to the output shaft 6 is meshed.

Then, the electromagnetic powder clutch 29 described above.
Is connected to the output side of the above-mentioned control unit 28 (see FIG. 5). In this case, the control unit 28 applies the drive torque obtained from the rotation speed set by the drive motor 26 to the transfer paper. It is designed to be changed depending on the stretched state. Specifically, as in the case described above, based on the signals from the microswitches 21 and 22 output when the transfer sheet is in the relaxed state and the tensioned state, In the relaxed state, the driving torque of the transport rollers 16 and 17 on the sheet ejection side is increased, and in the tense state, the driving torque of the transport rollers 16 and 17 on the sheet ejection side is decreased. The transfer sheet is prevented from buckling and image rubbing in each state.

Since this embodiment has the above-mentioned configuration,
The operation will be described with reference to the flowchart showing the operation of the control unit 28 as shown in FIG. That is, when a long transfer sheet is conveyed, it is determined whether the micro switch 21 of the micro switches 21 and 22 corresponding to the transfer sheet in the relaxed state is turned on. As described above, the output torque of the electromagnetic powder clutch 29 is increased, and whether the tension of the transfer sheet is set or not is determined by the operation state of the micro switch 22 by setting the driving torque. When the micro switch 22 is turned on, the electromagnetic powder clutch is turned on. The output torque of 29 is lowered to set the rotation speeds of the transport rollers 16 and 17 on the side of the paper discharge unit to the above-described state.

Further, the transport roller 1 on the side of the paper discharge section described above.
As a structure for changing the rotation speeds of 6 and 17 with respect to the transport roller located on the downstream side of the fixing device, the contact pressure of the driven roller with respect to the drive roller in the transport roller on the paper discharge unit side May be changed.

FIG. 9 shows the structure in this case. Specifically, for example, one of the transport rollers 16 on the sheet discharge side will be described. One end of a spring 31 arranged between the shaft 16B1 and the bracket 30 attached to the immovable portion is brought into contact with the shaft 16B1. The rotation speed (V2) of the transport roller 16 of the fixing device 10 is
The urging pressure is set so that a faster relationship (V1 <V2) can be set with respect to the rotation speed (V1) of the side transport roller 15.
The actuator 32 of the solenoid 32, which is fixed to the bracket 30, is provided on a part of the rotary support shaft 16B1.
A is pivotally attached, and this solenoid 32 is connected to the output side of the control unit 28 which performs the same control as that shown in FIG. 5, as shown in FIG. Therefore, when a long transfer sheet is conveyed, the control unit 28 sets the energized / de-energized state of the solenoid 32 according to the extension state of the transfer doctor. Specifically, the transfer sheet is relaxed. When in the state,
The biasing force of the spring 31 is effectively applied to maintain the rotation speed from the drive roller 16A, and
When the transfer paper is in a tension state, the contact pressure with respect to the drive roller 16A is reduced to cause slippage between the rollers, thereby lowering the conveyance force for the transfer paper, and as a result, the conveyance roller on the fixing device side is reduced. -Rotation speed (V1) of the roller 15 and rotation speed (V2) of the transport rollers 16 and 17 on the side of the paper discharge unit
The relationship (V1> V2) that delays is set.

Since the present embodiment is constructed as described above,
The operation will be described with reference to the flowchart showing the operation of the control section as shown in FIG. That is, it is determined whether or not the micro switch 22 corresponding to the tension state of the transfer paper is turned on, and when it is turned on, the solenoid 32 is excited to move the rotary support shaft 16B1 of the driven roller 16B to the arrow Z in FIG. To reduce the contact pressure to the drive roller 16A, and determine whether the micro switch 21 is turned on from this state, and when it is turned on, set the solenoid 32 to the non-excited state. To do. Therefore,
When the transfer sheet is in the loose state, as in the case of the above-described configuration, the rotation speed of the transport roller on the sheet discharge section side is the fixing device 10.
By making it faster than the transport roller 15 on the side, the sheet bending of the transfer sheet is prevented, and when the transfer sheet is in a tension state,
The rotation speed of the transport rollers 16 and 17 on the side of the paper discharge unit is made slower than that on the side of the fixing device 10, so that the image rubbing of the transfer paper can be prevented.

Further, FIG. 12 shows a structure in which the roller diameter of the drive roller in the transport roller is changed in order to change the rotation speed of the transport roller on the side of the paper discharge section. Is shown. That is, when the same description is given for the transport roller 16 similar to the case shown in FIG. 9, the drive roller 16A in this case is composed of an elastic body that is capable of contracting in the radial direction, and is in the axial direction. It has the habit of expanding in the radial direction when pressurized. Then, one end of the drive roller 16A in the axial direction is provided with a flange 16 fixed to the rotary support shaft 16A1.
The movement in the axial direction is regulated by A2, and the pressure member 33 fitted to the rotation support shaft 16A1 and movable in the axial direction is arranged at the other end in the axial direction. The roller pressing member 34 arranged near the rotary support shaft 16A1 faces the pressing member 33 described above.

As shown in FIG. 13, the roller pressing member 34 is composed of a swing member having a fulcrum shaft on a bracket 35 fixed to an immovable portion, and one of the swing ends is
A rod member 36 whose axial direction is set parallel to the rotary support shaft 16A1 is pivotally mounted via a pin 37, and the other end of the swinging end faces the above-mentioned pressing member 33. The rod member 36 described above has a solenoid 37 at one axial end thereof.
(See FIG. 12), the solenoid 37 is set in the operating position by the control unit described later so that the swinging position of the roller pressing member 34 with respect to the pressing member 33 is set. Is becoming

That is, the above-mentioned control unit is constituted by the same control unit 28 as that shown in FIG. 10, and the above-mentioned solenoid 37 is connected to this output side.

Then, in the control unit 28, the rotation speed of the transport roller 16 on the paper discharge unit side is changed according to the spread state of the transfer paper by the signals from the micro switches 21 and 22. The roller diameter of the drive roller 16A can be changed. Specifically, when the transfer paper is in a loose state, the transport rollers 16 and 1 on the paper discharge side are provided.
7 is faster than the rotation speed (V1) of the transport roller 15 on the fixing device side, and when the transfer paper is in a tension state, the transport roller 16 on the paper discharge unit side. , 17 is set so as to slow the rotation speed of the transfer rollers 15 on the fixing device side (V1> V2). Therefore, when the transfer sheet is in a relaxed state, the solenoid 37 is excited to move the rod member 36 in the axial direction, and the rod member 36 is rotated.
By swinging the roller pressing member 34, the pressing member 33 is pushed in by the other swing end, the drive roller 16A is expanded in the radial direction, and the roller diameter is set to a state in which the rotation speed increases. Further, when the transfer sheet is in a tension state, the solenoid 37 is set to the non-excited state, and the other swing end of the roller pressing member 34 is separated from the pressing member 33 by the axial movement of the rod member 36. Drive roller 16
The roller diameter of A is set so that the rotation speed becomes slow. The driven roller 16B has the same structure as that shown in FIG. 9, and the drive roller 16A is biased by the spring 31 so as to abut.

Since this embodiment has the configuration as described above,
The operation will be described with reference to the flowchart showing the operation of the controller as shown in FIG. That is, it is determined whether or not the micro switch 21 is turned on, and if it is turned on, it is determined that the transfer sheet is in a relaxed state, and the rotational speed of the drive roller 16A is increased so as to increase the rotation speed of the drive roller 16A. -Increase the radius by the method described above. Then, it is determined whether or not the micro switch 22 is turned on by the change of the roller diameter. When the micro switch 22 is turned on, it is determined that the transfer paper is in a tensioned state, and the driving roller 16A is driven so as to slow the rotation speed. The roller diameter of the roller 16A is returned to the initial state by the method described above.

[0038]

As described above, according to the present invention, the rotational speed of the transport roller positioned in the transport path of the transfer paper is adjusted according to the spread state of the transfer paper. When the paper is in a loose state, pulling the leading end side of the transfer paper in the conveying direction can prevent buckling at the rear end, and when the transfer paper is in a tensioned state, the leading end side of the transfer paper in the conveying direction. By slowing down the moving speed in, it is possible to prevent image rubbing on the trailing edge side and prevent deterioration of image quality.

[Brief description of drawings]

FIG. 1 is a layout view showing an example of a copying machine to which a transfer sheet conveying device according to an embodiment of the present invention is applied.

FIG. 2 is a schematic diagram for explaining an overall configuration of a transfer sheet conveying device according to an embodiment of the present invention.

FIG. 3 is a schematic diagram showing a main part of the overall configuration shown in FIG.

FIG. 4 is a developed view of a main part shown in FIG.

5 is a block diagram for explaining a configuration of a control unit used for the main part shown in FIG.

FIG. 6 is a flowchart for explaining the operation of the control unit shown in FIG.

FIG. 7 is a development view corresponding to FIG. 4 showing a modified example of the main part shown in FIG.

8 is a flowchart for explaining another operation of the control unit shown in FIG.

FIG. 9 is a schematic view showing another example of the main part shown in FIG.

10 is a block diagram for explaining a configuration of a control unit used in FIG.

11 is a flowchart for explaining the operation of the control unit shown in FIG.

12 is a schematic diagram showing still another example of the main part shown in FIG.

13 is a partially enlarged view of the main part shown in FIG.

FIG. 14 is a block diagram for explaining a configuration of a control unit used in the example shown in FIG.

FIG. 15 is a flowchart for explaining the operation of the control unit shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Writing section of a copying machine 2 Photoconductor drum 10 Fixing device 11 Discharging / conveying path 11A Discharging tray forming a discharging section 12 Curved conveying guides 13 and 14 Conveying guides 15 Conveying roller on fixing device side 15A Driving roller 15B Driven rollers 16 and 17 Transport rollers 16A and 17A on the side of the discharge unit 16A and 17A Drive rollers 16B and 17B Driven rollers 19 Swing support members 21 and 22 Micro switches 26 serving as detection means 26 Drive motors 28 Control unit 29 Electromagnetic powder clutch 32, 37 Solenoid

Claims (8)

[Claims] 1. A transfer paper conveyance path is provided between a fixing device for fixing a transfer paper carrying an unfixed image transferred from an image carrier and heating the transfer paper while sandwiching and conveying the transfer paper. The transfer paper transport path includes a pair of curved guide members facing each other across the transport path on the downstream side of the fixing device in the transport direction of the transfer paper, and a plurality of transfer guide paths are arranged along the transport path.
In a transfer paper transporting device composed of a pair of transport rollers facing each other across a transport path, a drive roller disposed on the back side of the image carrying surface of the transfer paper in the transport roller, The driven roller, which is arranged so as to be able to come into contact with and separate from the drive roller and is located on the image surface side of the transfer sheet, and the driven roller, which is rotatably supported at the swing end, is driven by the drive roller. A rocking support member that is normally provided with a tendency to abut against a roller and is provided so as to be rockable, and a rocking support member that is disposed so as to face the other rocking end of the rocking support member. A means for detecting the amount of rocking of the member, and a transport roller located on the side of the paper discharge section in the transfer paper transport path.
Means for changing the rotation speed with respect to the conveying roller located downstream of the fixing device, and means for detecting the swing amount of the swing support member are connected to the input side, and A means for changing the rotation speed is connected to the output side, and the rotation speed of the transport roller on the discharge section side is changed according to the spread state of the transfer paper by a detection signal from the detection means. And a control unit for controlling the transfer sheet. 2. The transfer sheet conveying device according to claim 1,
When the transfer sheet is in a loose state, the control unit controls the rotation speed of the transport roller on the sheet discharge section side to the transport roller located on the downstream side of the fixing device in response to a signal from the swing amount detection means of the swing support member. -When the transfer sheet is in a tension state, the rotation speed of the transport roller on the side of the paper discharge unit is slower than that of the transport roller located on the downstream side of the fixing device. Transfer paper transport device. 3. A transfer paper conveying path set between a fixing device for heating and fixing a transfer paper carrying an unfixed image transferred from an image carrier while nipping and transferring the transfer paper to a paper discharging section. The transfer paper transport path includes a pair of curved guide members facing each other across the transport path on the downstream side of the fixing device in the transport direction of the transfer paper, and a plurality of transfer guide paths are arranged along the transport path.
In a transfer paper transporting device composed of a pair of transport rollers facing each other across a transport path, a drive roller disposed on the back side of the image carrying surface of the transfer paper in the transport roller, The driven roller, which is arranged so as to be able to come into contact with and separate from the drive roller and is located on the image surface side of the transfer sheet, and the driven roller, which is rotatably supported at the swing end, is driven by the drive roller. A rocking support member that is normally provided with a tendency to abut against a roller and is provided so as to be rockable, and a rocking support member that is disposed so as to face the other rocking end of the rocking support member. A means for detecting the amount of rocking of the member, and a transport roller located on the side of the paper discharge section in the transfer paper transport path.
Means for changing the driving torque with respect to the transport roller located downstream of the fixing device, and means for detecting the swing amount of the swing support member are connected to the input side, and A means for changing the rotation speed is connected to the output side, and the drive torque of the transport roller on the paper discharge section side is changed according to the spread state of the transfer paper by a detection signal from the detection means. And a control unit for controlling the transfer sheet. 4. The transfer sheet conveying device according to claim 3,
When the transfer sheet is in a loose state, the transport roller on the sheet discharge side applies the drive torque of the drive roller on the transport roller to the downstream side of the fixing device when the transfer sheet is in a loose state. Larger than the drive roller of the transport roller located at
Then, when the transfer sheet is in a tension state, the drive torque of the drive roller on the side of the paper discharge unit is made smaller than that of the transport roller located on the downstream side of the fixing device. Transfer paper transport device. 5. A transfer paper conveyance path is provided between a fixing device for heating and fixing the transfer paper carrying an unfixed image transferred from an image carrier while nipping and transferring the paper to a paper discharge section. The transfer paper transport path includes a pair of curved guide members facing each other across the transport path on the downstream side of the fixing device in the transport direction of the transfer paper, and a plurality of transfer guide paths are arranged along the transport path.
In a transfer paper transporting device composed of a pair of transport rollers facing each other across a transport path, a drive roller disposed on the back side of the image carrying surface of the transfer paper in the transport roller, The driven roller, which is arranged so as to be able to come into contact with and separate from the drive roller and is located on the image surface side of the transfer sheet, and the driven roller, which is rotatably supported at the swing end, is driven by the drive roller. A rocking support member that is normally provided with a tendency to abut against a roller and is provided so as to be rockable, and a rocking support member that is disposed so as to face the other rocking end of the rocking support member. A means for detecting the amount of rocking of the member, and a transport roller located on the side of the paper discharge section in the transfer paper transport path.
Means for changing the contact pressure of the driven roller with respect to the drive roller of the roller and means for detecting the amount of rocking of the rocking support member are connected to the input side, and for changing the contact pressure. Means connected to the output side, and a control unit for changing the contact pressure of the driven roller in the transport roller on the sheet discharge section side in accordance with the spread state of the transfer sheet by the detection signal from the detection section. And a transfer paper transporting device. 6. The transfer sheet conveying device according to claim 5,
When the transfer paper is in a loose state, the transport roller on the paper discharge side detects the contact pressure of the driven roller with respect to the drive roller in the transport roller by the detection signal of the swing amount of the swing support member. A transfer sheet conveying device configured to raise the contact pressure and lower the contact pressure of the driven roller with respect to the drive roller on the sheet discharge section side when the transfer sheet is in a tension state. 7. A transfer paper conveyance path is provided between a fixing device for fixing the transfer paper carrying an unfixed image transferred from an image carrier and heating it while nipping and conveying the transfer paper to a paper discharge section. The transfer paper transport path includes a pair of curved guide members facing each other across the transport path on the downstream side of the fixing device in the transport direction of the transfer paper, and a plurality of transfer guide paths are arranged along the transport path.
In a transfer paper transporting device composed of a pair of transport rollers facing each other across a transport path, a drive roller disposed on the back side of the image carrying surface of the transfer paper in the transport roller, The driven roller, which is arranged so as to be able to come into contact with and separate from the drive roller and is located on the image surface side of the transfer sheet, and the driven roller, which is rotatably supported at the swing end, is driven by the drive roller. A rocking support member that is normally provided with a tendency to abut against a roller and is provided so as to be rockable, and a rocking support member that is disposed so as to face the other rocking end of the rocking support member. A means for detecting the amount of rocking of the member, and a transport roller located on the side of the paper discharge section in the transfer paper transport path.
Means for changing the diameter of the roller for driving the roller, and means for detecting the amount of rocking of the rocking support member are connected to the input side, and means for changing the rotational speed is output. And a control unit connected to the side for changing the roller diameter of the drive roller in the transport roller on the side of the sheet discharge unit in response to the detection signal from the detection unit according to the spreading state of the transfer sheet. A transfer paper transporting device comprising: 8. The transfer sheet conveying device according to claim 7,
When the transfer sheet is in a loose state, the control section increases the roller diameter of the drive roller in the transport roller on the sheet discharge section side in response to a signal from the swing amount detection means of the swing support member. Then, when the transfer paper is in a tension state, the transfer paper transfer device is configured to reduce the roller diameter of the drive roller in the transfer roller on the side of the paper discharge unit.