JP3472767B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrostatically absorbing a transfer material.
To an image forming apparatus having a transfer material conveying means for attaching and conveying.
When removing the transfer material from the transfer material transporting means,
Prevents non-fixed images formed on copying materials from being disturbed
The present invention relates to an image forming apparatus. [0002] 2. Description of the Related Art A conventional image forming apparatus is shown in FIG.
Was configured to. The image forming apparatus shown in FIG.
Drive roller 11 and driven roller 22 as transfer material conveying means
Using the endless transfer / conveying belt 10 stretched at
Of each type with the photosensitive drum 1 as the center
Is arranged. The image forming process in this apparatus is as follows.
It is as follows. [0004] First, a charger 2 is applied to the surface of the photosensitive drum 1.
After applying a uniform charge, it should be formed by the exposure device 3.
By irradiating light according to a desired image, an electrostatic latent image is formed.
Form. The image forming medium 23 is stored inside the developing machine 4.
Almost constant charge is given by friction charging
However, the image forming medium 23 is statically moved according to the electrostatic latent image.
Adhered by electric force to form visible image on photoreceptor drum
To achieve. On the other hand, the transfer material 9 is
Is fed in the direction of arrow A of FIG.
Is conveyed, and the contact between the photosensitive drum 1 and the transfer conveyance belt 10
Nip area. Here the transfer conveyor bell
A belt 10 from the transfer charger 5 to the image forming medium 23
Since the charge of the opposite polarity to the electric charge is given,
The image forming medium 23 on the system 1
The image is transferred onto the transfer material 9. Transfer material 9 passes through nip area
Of the charge applied to the transfer / conveying belt 10
And the same polarity as the image forming medium 23 on the photosensitive drum 1
Is transferred to the transfer material 9. Therefore, the transfer material 9 is transferred.
Transfer and transfer due to electrostatic attraction with the charge on the transfer belt 10
It is conveyed while being attracted to the belt 10. Image forming medium on the surface
The transfer material 9 on which the visible image by the transfer member 23 is transferred is grounded.
Separated from the transfer conveyance belt 10 on the drive roller 11
Further, the fixing device 1 on the downstream side passes through the grounded guide member 14.
2, the image forming medium 23 is melted to fix the image.
And is transported in the direction of arrow B in the figure. The photosensitive drum
1 is erased by the erase lamp 6, and
The remaining image forming medium 23 is removed by the cleaner 7
To prepare for the next new image formation. Also transfer transfer belt
The image forming medium 23 scattered on the
Removed. [0005] In the above prior art, the drive is
The transfer material 9 is transferred from the transfer material transport belt 10 on the moving roller 11.
Generated between the transfer material 9 and the transfer conveyance belt 10 when peeling
Between the charge on the transfer belt 10 and the transfer material
The gap electric field E generated by the charge on the
Gives the minimum electric field curve that causes Paschen discharge.
If the value is larger than the value of equation (1),
Discharge occurs, and due to the influence, the toner is transferred onto the transfer material 9.
The image forming medium 23 may be scattered and disturb the image.
Was. [0006] (Equation 1) In the worst case, if the drive roller 11
The image forming medium 23 scatters on the structural member 16 disposed thereon.
However, depending on the long-term use, it may be deposited on the structural member 16.
Image forming medium 23 falls onto transfer material 9 and
Image distortion. [0008] In order to solve this, in the prior art
As shown in FIG. 3, the drive roller 11 is used as a counter electrode.
And a charger that generates an electric charge having a reverse curvature to the electric charge on the transfer material 9
20 to neutralize the charge on the transfer material 9,
The generation of electric discharge was suppressed by reducing the gap electric field. I
However, in this method, the charging device 20 is used to form an unfixed image.
Do not charge the transfer material 9 from the surface to which the medium 23 has been transferred.
Must use a corona discharger that can supply electric charges without contact
Harmful oxidizing gas is generated.
And an electrode for generating corona discharge,
Because of the application of an electric field that is inversely curved to 23, it can be used for a long time.
The scattered image forming medium 23 is collected, and the charging device 20
There is a disadvantage that the performance of the body is reduced. [0009] It is an object of the present invention to eliminate the above drawbacks and to provide
When the copying material 9 is peeled off from the transfer / conveying belt 10,
Equipped with a separation section that effectively suppresses electricityFrom the transfer material
Of image forming mediumHigh quality images can be obtained
An object of the present invention is to provide an image forming apparatus. [0010] Means for Solving the Problems To achieve the above object,
In the image forming apparatus of the present invention,
The member provided at the transfer material peeling portion of
A bias voltage having the opposite polarity to the charge polarity held by the image forming medium
A configuration for applying pressure was adopted. Further, the transfer material 9 is transferred from the transfer conveyance belt 10.
Immediately after peeling, the contact-type static elimination member 15 is
Another grounding member that removes the electric charge from above and comes close to the transfer material 9
Between the image forming medium and the image forming medium 23.
It acts to eliminate the adverse effects that are drawn. Also transfer member
9 from the surface on which the image forming medium 23 has not been transferred.
9, the image forming medium 23 is not disturbed.
And the image quality is maintained. [0012] DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the principle of the present invention will be described with reference to FIGS.
4 and FIG. A conventional roller near the drive roller 11
Electricity at a part where the copying material 9 is separated from the transfer / conveyance belt 10
The typical structure is as shown in FIG.
In a region 1 which indicates a portion where 10 closely adheres, the transfer material 9 has
The capacitance C1 and the capacitance C2 of the transfer conveyance belt 10
Are connected in series, and the equivalent circuit with C2 side grounded to zero potential
The part where the transfer material 9 is peeled off from the transfer conveyance belt 10
In the area 2 indicating the following, the capacitance of the gap 25 between C1 and C2 is
It is represented by an equivalent circuit with the quantity C3 inserted. Here the authors
According to actual measurements, C1 is 1026 pF and C2 is 474 pF.
Further, in the area 1, the transfer material 9 and the transfer conveyance belt 10
The potential V1 with respect to the drive roller 11 in the state where
-1800 V, a drive roller using the transfer / conveying belt 10 alone
The potential V2 with respect to No. 11 was -650V. Now, FIG.
The equivalent circuit of area 1 or area 2 forms a closed circuit
The accumulated charge escapes to the outside.
And not. That is, the transfer material 9 is peeled from the transfer conveyance belt 10.
At the time of separation, a gap is provided between the transfer material 9 and the transfer conveyance belt 10.
25, and the equivalent circuit is changed from the region 1 to the region 2.
Even if it moves to the thing, it is obtained using the value of V1, C1 and C2.
The value of the total charge amount Q = 585 nC does not change.
The charge is shared by each of C1, C2 and C3
State. From this, the transfer material 9 in the area 2
Drive in a state where there is a gap 25 between the transfer conveyance belt 10
The potential V1 'with respect to the moving roller 11 can be expressed by equation (2).
You. [0014] (Equation 2) However, the capacitance C3 of the gap 25 is a vacuum dielectric.
Ratio is ε, void length is D [cm], area is S [30
Equation (3) is obtained. [0016] (Equation 3) Based on the above results, the electric field applied to the gap 25
When E is obtained, equation (4) is obtained, and the gap length and the space shown in FIG.
The curve 26 shows the relationship between the gap electric fields. [0018] (Equation 4) FIG. 6 shows the passive state obtained from the equation (1).
The minimum electric field curve 27 that causes the discharge is shown.
In the gap length where the line 26 and the curve 27 intersect, the first time
Discharge occurs. In this case, the discharge reduces the gap electric field
However, even after discharge, the air gap electric field higher than curve 27
If so, the second and third discharges are repeated. Therefore
To mitigate the gap discharge, at a lower gap electric field,
And intersects curve 27 at the point where the gap length is larger
It is necessary to use the formula (4)
Is achieved by reducing or increasing the denominator
It is. In order to reduce the numerator of the formula (4), V
Can be achieved by reducing the difference between 1 'and V2.
However, as shown in the prior art, this
This is a method for removing electricity and reducing V1 '.
Has disadvantages. Therefore, in the present invention, the denominator of the equation (4) is small.
It adopts a method of cutting. That is, in order to solve the above-mentioned problems, the present invention
In this case, as shown in FIG.
10 to reduce the electric field in the air gap created between
Drive roller via ground circuit 13 having capacitive element 18
Means for grounding 11 is used. In this way, drive
If the transfer material 9 near the roller 11 is the transfer conveyance belt 10
The electrical configuration in the area 2 showing the part to be peeled off is shown in FIG.
As shown in the figure, in addition to C1, C2 and C3, the ground side of C2
It is expressed by an equivalent circuit with C4 added, and the air gap electric field at that time
E 'is given by equation (5). [0022] (Equation 5) The value of C4 to be added is 2000p
F, 120 pF, 20 pF, and
The obtained curves are 28, 29, and 30, respectively,
This is shown in FIG. As shown in FIG. 6, curves 28, 29, 30
By reducing the capacitance load 18 to be added,
The intersection with curve 27 is at a lower airgap field and at a higher
The point shifts to a point where the gap length becomes large, and the discharge decreases. Hereinafter, the present invention will be described.Reference examples andSpecific examples
A more detailed description will be given. (Reference example1) BookReference exampleThe description will be made with reference to FIGS. Figure 1
1 shows a basic configuration diagram of an image forming apparatus according to the present invention. image
The basic components involved in the forming process are the same as in FIG.
However, the drive roller 11 is grounded via the grounding circuit 13.
ing. Here, the photosensitive drum 1 has a minus band.
The developing method by the developing machine 4 using an electric
Image forming medium 23 by a reversal developing method using a component developer.
Has a negative charge. The transfer charger 5 has a positive
Rotoron charger controls the corona current value
Takes a method of controlling the potential applied to the transfer charger 5
It is also possible. Further, the transfer conveyance belt 10 is at normal temperature and normal humidity.
Volume resistance at 10 to 10 13 Ω · cm to 10 13
It is an endless belt with a square of Ω · cm and thickness of 0.06cm.
The capacitance of the material 9 and the transfer conveyance belt 10 is 10
At 26 pF and 474 pF, the transfer material 9
The drive roller 11 with the
Position is -1800 V, and the driving speed of the transfer / conveyor belt 10 alone is
The potential for the mirror 11 is -650V. These articles
The following isReference examples andIt is the same in the embodiment. Image formation process and transfer in this apparatus
The process of transporting the material 9 will be described in detail below. First
The surface of the photoreceptor drum 1 is uniformly negatively charged by the charger 2.
After the charge is applied, a desired image to be formed by the exposure device 3 is formed.
By irradiating the image area with light,
An electrostatic latent image closer to zero potential is formed than the ground part.
You. The image forming medium 23 stored inside the developing machine 4
Almost constant negative charge is given by triboelectric charging.
The potential of the background portion and the electrostatic latent image portion.
By applying to the developing machine 4 a potential which is halfway between the potentials
The image forming medium 23 is attracted to only the electrostatic latent image,
A visible image is formed on the body drum 1 by the image forming medium 23
Is done. On the other hand, the transfer material 9 is
Is fed in the direction of arrow A of FIG.
Is conveyed, and the contact between the photosensitive drum 1 and the transfer conveyance belt 10
Nip area. Here the transfer conveyor bell
To the printer 10, a positive charge is given from the transfer charger 5.
Image forming medium having a negative charge on the photosensitive drum 1
The body 23 is transferred onto the transfer material 9 in this nip area.
It is. When the transfer material 9 passes through the nip area,
The photosensitive drum is affected by the positive charge given on the
The negative polarity of the same polarity as the image forming medium 23 on the ram 1
The load is transferred to the transfer material 9. Therefore, the transfer material 9 is transferred and transferred.
Transfer and transfer by electrostatic attraction force with positive charge on belt 10
It is adsorbed on the transport belt 10 and transported. With drive roller 11
The transfer material 9 conveyed in the vicinity is transferred to the transfer conveyance belt 10 here.
Is bent along the cylinder of the drive roller 11, the transfer material
9 Separation by overcoming the electrostatic attraction force due to its own rigidity
start. At this time, between the transfer material 9 and the transfer conveyance belt 10
Gaps are formed in the transfer material peeling portion in FIG.
As shown in the formula configuration diagram, the driving roller 11
18 is grounded by a ground circuit 13 having
Is reduced without Paschen discharge.
The copying material 9 is separated. However, the image shape at the peeling part
The scattering state of the medium 23Reference exampleStatic to insert in
When the value of the capacitance element 18 is 2000 pF, the driving roller
Improved almost the same as the state where 11 was grounded to zero potential
Was not seen. BookReference exampleImproved in
In this case, insert the capacitance element 18 of about 120 pF or less.
And the flying of the image forming medium 23 at the peeling section.
There was almost no scattering. The transfer and transport belt 10 is separated as described above.
The transferred transfer material 9 is sequentially connected to the guide member 14 which is grounded next.
It is transported by touch. At this time, the transfer material 9 is still charged.
Since the load is held, the transfer material 9 and the guide member 14
Poor contact, gap between transfer material 9 and guide member 14
Occurs, a discharge occurs during this time, and an image on the transfer material 9 is formed.
The forming medium 23 may be disturbed. This is guide member 1
This is a phenomenon that occurs because 4 is grounded.
When the member 14 is removed, the negative charge on the transfer material 9
And the negative charge of the image forming medium 23 repels,
The image forming medium 23 is likely to be scattered. Follow
When the transfer material 9 contacts the guide member 14,
In this state, the image charge of the charge of the transfer material 9 can be generated.
It is necessary to ground metal members.
No. Also, the contact state between the guide member 14 and the transfer material 9 described above.
In order to prevent the image forming medium 23 from scattering due to a decrease in
The surface on which the transfer material 9 runs on the guide member 14 is
The surface on which the transfer material 9 runs on the belt 10 is parallel
It is desirable that the step between both running surfaces is small.
It is ideal. BookReference exampleIn the study of the transfer material, as shown in FIG.
When the guide member 9 moves in the direction of the arrow in FIG.
4 at the distance indicated by C in FIG.
mm and the running surface A of the transfer material 9 of the transfer conveyance belt 10
The step D between the guide member 14 and the running surface B of the transfer material 9 is 2 mm.
And the running surface B is positioned lower than the running surface A in the figure.
It is installed in parallel with. Now, assuming that the step D is 0 mm,
Since the transfer material 9 is in close contact with the transfer conveyance belt 10,
The position after the copying material 9 is separated from the transfer conveyance belt 10 is moved.
The transfer material 9 is transported here because it is below the line B in the figure.
The transmission stops. To avoid this, step D
Needs to be set to about 2 mm.
Then, a gap is generated between the transfer material 9 and the guide member 14,
Experiments show that the scattering of the image forming medium 23 increases.
Has been confirmed by The transfer material 9 is separated from the guide member 14.
In this case, there is an electric charge on the transfer material 9 and
Discharge also occurs. Now, the transfer material 9 is
Some charge leakage from the transfer material 9 during contact and conveyance
Then, the charge of the transfer material 9 is removed. Therefore, the transfer material 9 and the gas
When the contact time of the guide member 14 can be extended, or
Until the material 9 fixes the image forming medium 23 by the fixing machine 12
In the case of a configuration that never leaves the guide member 14 during
Does not have the above-mentioned discharge problem. However, the guide member 14 and the
When the contact time of the copying material 9 is short, the transfer material 9
The non-image forming surface of the transfer material 9
In FIG. 7, the charge of the transfer material 9 is removed from the lower side of the transfer material 9.
It is desirable to provide a member to perform. BookReference exampleIn this case, the guide member 14 and the
In addition to increasing the contact property of the copying material 9, the charge removal of the transfer material 9
For the purpose of performing, the back surface is placed on the surface of the guide member 14 through which the transfer material 9 passes.
A brush-like neutralizing member 15 for neutralizing the transfer material 9 from the surface is provided.
Has been placed. Further, the bristle tip of the charge removing member 15 is
Turn to the downstream side in the transport direction so as not to disturb the transport
It is attached as follows. By this method, the transfer material 9 is finely divided.
When the transfer material 9 has small irregularities,
Of the static elimination member 15 when mechanically separated from the
The brush part follows the movement of the transfer material 9 and always keeps contact.
Behave as if. At the same time, a flat guide
The contact area with the uneven transfer material 9 is increased as compared with the material 14.
As a result, the static elimination performance is improved and sufficient static elimination can be performed in a short time.
I can do it. The provision of the charge removing member 15 as described above
Therefore, the transfer material 9 is guided by the guide member in a state where the charge is sufficiently removed.
14 and fixing of the image by the fixing device 12 which is the next process.
Is carried out, and then transported in the direction of arrow B in the figure. After completion of the transfer, the photosensitive drum 1
The negative charge is removed by the erase lamp 6 and remains.
The removed image forming medium 23 is removed by the cleaner 7 and
For new image formation. Also, the transfer material 9 peeled off
Thereafter, the image forming medium 23 scattered on the transfer conveyance belt 10
Is removed by the cleaner 8 and is the same as that of the photosensitive drum 1.
To prepare for new image formation. In the above configuration, the image forming medium
Until the transfer material 9 onto which the transfer material 23 is transferred passes through the fixing device.
Gap discharge and image formation medium 23
An image forming apparatus that can reduce scattering and obtain high-quality images
Can be provided. (Reference example2) BookReference exampleThenReference exampleBecause it has the same configuration as
Although not shown,Reference exampleAt the ground circuit 13
Instead of the inserted capacitance element 18, the capacitance is about 12
The same effect can be obtained by using a constant voltage element of 0 pF or less.
It is. In experiments, the capacitances were 120 pF and 57 pF
Of the image forming medium 23 at the peeling section.
The result is that the scattering is reduced. (Reference example3) BookReference exampleThen, a schematic configuration diagram of the transfer material peeling portion in FIG. 8 and
This will be described with reference to the basic configuration diagram of the image forming apparatus shown in FIG. BookReference exampleIn the image shape in FIG.
The basic components involved in the formation process are the same as in FIG.
However, the member for cleaning the transfer / transport belt 10 is bias-cleared.
17 is different. Transfer transfer belt 10
The bias cleaner 17 to be cleaned basically adheres.
Of a polarity opposite to that of the image forming medium 23 having a negative charge.
Applied to the cleaner, and the grounded driven roller 24
, The image forming medium 23 is suction-cleaned.
Image forming medium to be cleaned and to be sucked
23 must have a negative charge. others
Transfer conveyor belt 10 is cleaned by bias cleaner 17
Before receiving the sweep operation, the electric charges of the image forming medium 23 are aligned.
It is necessary to provide the pre-cleaner charger 21. BookReference exampleThen, as shown in FIG.
To the position where the drive roller 11 is used as the counter electrode.
Charger 21 is provided to add a new roll member.
Along with the comb, the cross-section is reverse
And a negative voltage is applied
Using a corona discharger with wire electrodes 32
The upper side surface of the transfer member 9 in FIG.
Also serves as the id member 33. Also bookReference exampleThen
The guide member 33 which is the upper surface of theReference example
The same static elimination member 15 as that shown in FIG. [0039]Next, examples of the present invention will be described.
You.Now, the corona current from the pre-cleaner charger 21 is
From the ear electrode 32 to the shield member 31 and the drive roller 11 side
And flows into the drive roller 11 side.
The image forming medium 23 is charged by the flow.
You. However, in this embodiment, the driving roller 11 is
Grounding via the element 18 causes the
The charged current charges the electrostatic capacitance element 18 and
As a result, the potential of the same polarity as the wire electrode 32 rises. This shadow
As a result, current stops flowing to the drive roller 11 side,
The image forming medium 23 is no longer charged. In addition, drive
When the potential of the roller 11 is negatively biased,
Repelled by the negative charge of the image forming medium 23,
The scattering of the image forming medium 23 from the copying material 9 is promoted. This
This means that the drive roller 11 has via holes as shown in FIG.
Connected to the drive roller 11 and a bias voltage
Is applied, the voltage from -100V to 100V
The scattering of the image forming medium 23 is almost changed by applying the glaze.
However, when a bias of about 1000 V is applied,
On the other hand, when a bias of about -1000 V is applied,
This has been confirmed by experimental results in which the scattering increases drastically. [0040](Reference Example 4) This reference example Then, as shown in FIG.
Drive 19 by the grounding circuit 13 in which
A configuration was adopted in which the ground was grounded. Also bookReference exampleUsed in
When the specific resistance value of the transfer conveyance belt 10 is about 600 MΩ or more
Yes, flows from the pre-cleaner charger 21 to the drive roller 11
Current is limited by the specific resistance of the transfer belt 10
The resistance element connected to the capacitance element 18
It is desirable that the value of 19 is lower than about 100 MΩ.
New But the bookReference exampleThen, the electric current flowing into the drive roller 11
Current is −15 μA, and the potential is −
1500V, and the image forming medium 23
Splashes increase dramatically. In addition, the potential is -15 V with a resistance of 1 MΩ.
But it is almost the same as the ground contact
Therefore, the function of the capacitance element 18 is lost. Therefore the bookreference
An exampleThen, the potential of the image forming medium 23 is set to about -100 V in terms of potential.
There is no effect on scattering, and the function of the capacitance element 18 works.
The scattering is reduced by using a resistance element 19 of about 10 MΩ.
I was able to. BookReference exampleAs shown in FIG.
The driving circuit is connected to the grounding circuit 13 in which the resistance elements 19 are connected in parallel.
When the roller 11 is grounded, the drive roller 11 is
The present invention can be applied to the case where the counter electrode of the pre-charger 21 is not used.
You. This is because, for example, the charge of the transfer conveyance belt 10 is driven.
The electric charge leaks to the moving roller 11 side, and the electric charge is stored in the capacitance element 18.
It is the case that it is piled up, but the bookReference exampleTransfer used for
In the feed belt 10, charge leakage to the drive roller 11
And the potential of the capacitance element 18 is around -15 V
Therefore, even if the resistance elements 19 are not connected in parallel, the image forming medium
There was no effect on the suppression of scattering of the body 23. (Reference Example 5) BookReference exampleThen aboveReference exampleGuide member 14 used in
Therefore, a configuration that is desirably further added will be described.
You. That is,Reference example, The guide member of the transfer material 9
14 is used with grounding. In this case, FIG.
In a state where the transfer material 9 is conveyed in the direction of arrow A,
At the end B of the transfer material 9 perpendicular to the transport direction, the image forming medium
The thickness direction of the transfer material 9 generated by the electric charge of the body 23 itself
Image forming medium 23 indicated by arrow C in addition to the visual power to
The suction force along the line of electric force from the head to the guide member 14 is an image
It works on the medium 23 itself. Therefore, it is very close to the end B.
When the image forming medium 23 is transferred to the position,
The force along the direction of arrow C rather than the force acting in the thickness direction of the copying material 9
Is stronger, and the image forming medium 23
On the other hand, it may fly. Book to prevent thisReference example
Then, as shown in FIG. 11, the transfer material 9 contacts the guide member 14.
When passing through, of the contact surface of the guide member 14,
Including at least the part whose surface is not covered with the transfer material 9,
In addition, the portion of the transfer material 9 close to the above-mentioned end is defined as
Using a method of applying or coating a small resistor 34
You. In addition, alumite or teflo is used as the low-resistance element.
Processing, etc.Reference exampleThen anodized
And the force acting in the thickness direction of the transfer material 9 is maintained.
The force along the direction of arrow C is reduced
The scattering of the image forming medium 23 to the member 14 was reduced. (Reference example 6) BookReference exampleIsReference Example 5On the guide member 14 at
FIG. 12 shows another method for reducing the scattering of the forming medium 23.
Shown in Ie bookReference exampleThen, the resistor 34
Instead of coating or coating the guide member 14 with
The force acting in the thickness direction of the transfer material 9 is maintained, and
That can reduce the force along the line of electric force on the guide member 14
The guide member 14 is grounded via an air circuit 35,
In addition to the guide member 14, the static elimination member 15 is simultaneously
35 can be connected. However, in this case, static elimination of the static elimination member 15 is performed.
The performance may be reduced.
Only the member 14 is connected to the electric circuit 35,
It is necessary to ground with another route. BookReference exampleThen, the guide section
The electric circuit 35 connected to the material 14 is about 10 MΩ.
Since we studied using a resistance element or a constant voltage element,
However, in both cases, the image forming medium
23 was found to be reduced. (Reference Example 7) BookReference exampleAlso,Reference Example 5On the guide member 14 at
FIG. 13 shows another method for reducing the scattering of the forming medium 23.
Is shown in Ie bookReference exampleThen, the transfer material 9 is transported.
In the direction perpendicular to the direction, the width of the transfer material 9 is
When the width of the pad member 14 is A, the width A is equal to the width B.
Or the width A is smaller than the width B,
That is, the transfer material 9 passes through the guide member 14 in contact with one surface thereof.
When transferring, the transfer material 9 of the contact surface of the guide member 14 is
The entire surface of the image forming medium 2 is covered with
3 does not scatter to the guide member 14. (Reference Example 8) BookReference exampleIsReference Example 7Guide member 1 based on the same idea as above
4 shows a method for reducing the scattering of the image forming medium 23 onto
FIG. 14 shows a configuration diagram of the guide member 14. That is, the book
Reference exampleThen, along the line of electric force to the guide member 14 described above,
In order to reduce the force, the distance between the transfer material 9 and the guide member 14 is reduced.
Can also be achieved by releasingReference exampleThen, transfer material 9
Is passed through the guide member 14 while contacting the guide member 14.
The surface of the contact surface of the member 14 is covered with the transfer material 9.
The non-existent portion A has a step C from the running surface B of the transfer material 9.
It has a remote structure. AlsoReference exampleThe gas shown in 1 to 3
The static elimination member 15 is installed on the transfer material 9 running surface of the guide member 14.
That is, the charge removing member 15 itself is connected to the guide member 14 and the transfer material.
9 plays the role of increasing the distance from the image to the guide member 14.
The scattering of the forming medium 23 is reduced. (Reference Example 9) BookReference exampleIs the flight of the image forming medium 23 to the guide member 14.
In the method of reducing scattering, the transfer material 9 is orthogonal to the transport direction.
When two types of width are usedReference exampleAnd figure
FIG. 15 shows a configuration diagram. In FIG. 15, transfer materials are 9A and 9
B, the former being of small size,
Before the paper, so that the left ends of the transfer materials 9A and 9B are aligned.
Transported from the back to the back. The guide member is 14a.
And 14b are divided into two regions, and both guide members 14a, 1
A charge removing member 15 is provided on the contact surface of the transfer material 4b with the transfer materials 9A and 9B.
is set up. However, the guide member 14a is the transfer material 9
A, 9B, the area where the guide member 14 is always in contact during transportation.
b indicates that only the transfer material 9B is in contact and the transfer material 9A is being transported.
The area where the surface is exposed is shown. Therefore, under normal conditions,
During the conveyance of the material 9A, the image forming medium 23
b. BookReference exampleThen, guide member 1
4a is always grounded, and the guide member 14b is
When A is transported, the switch connected to 14b
When the transfer element 9B is transported when the transfer element 9B is
Is configured so that the switching element 36 is closed.
To achieve. Therefore, when the transfer material 9A is transported,
The member 14b enters a floating potential state, and the image forming medium 23
A force along the line of electric force from the head to the guide member 14b is generated
Without scattering the image forming medium 23 to the guide member 14b.
Does not happen. When the transfer material 9B is transported,
The transfer member 14b is grounded, and the force in the thickness direction of the transfer material 9B is applied.
Occurs,Reference exampleOf the image forming medium 23 indicated by 1 to 3
Scattering is reduced. BookReference exampleIn this switchon
The signal S for controlling the opening and closing of the printing element 36 is a transfer (not shown).
In the material supply device, which of the transfer materials 9A and 9B is selected
The switching element 36
The signal is to be transmitted. However, the transmission source of the signal S is above
It is also possible to use a method other than the
Selection may be made by switching, or externally of the image forming apparatus.
May be based on the signal transmitted from. [0047] According to the present invention, an image is formed from a transfer material.
There is an effect that scattering of the medium can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a basic configuration diagram of an image forming apparatus according to the present invention. FIG. 2 is a basic configuration diagram of an image forming apparatus according to the related art. FIG. 3 is a basic configuration diagram of an image forming apparatus according to the related art. FIG. 4 is an equivalent circuit in a transfer material peeling section according to the related art. FIG. 5 is an equivalent circuit in a transfer material peeling section according to the present invention. FIG. 6 is a diagram showing a relationship between a gap length and a gap electric field. FIG. 7 is a schematic configuration diagram of a transfer material peeling unit showing Reference Example 1. FIG. 8 is a schematic configuration diagram of a transfer material peeling section showing Reference Example 3. [9] The basic configuration of an image forming apparatus in Example 3. FIG. 10 is a schematic configuration diagram of a guide member for explaining Reference Example 5 ; FIG. 11 is a schematic view of a guide member showing Reference Example 5 . FIG. 12 is a schematic configuration diagram of a guide member showing Reference Example 6 . FIG. 13 is a schematic configuration diagram of a guide member showing Reference Example 7 . FIG. 14 is a schematic configuration diagram of a guide member showing Reference Example 8 . FIG. 15 is a schematic configuration diagram of a guide member showing Reference Example 9 . FIG. 16 is a schematic configuration diagram illustrating a transfer material peeling unit according to the embodiment of the present invention . DESCRIPTION OF SYMBOLS 1: photosensitive drum, 2: charger, 3: exposure device, 4: developing machine, 5: transfer charger, 6: erase lamp, 7: cleaner, 8: cleaner, 9: transfer material, DESCRIPTION OF SYMBOLS 10 ... Transfer conveyance belt, 11 ... Drive roller, 12 ... Fixing machine, 13 ... Ground circuit, 14 ... Guide member, 15 ... Static elimination member, 16 ... Structural member, 17 ... Bias cleaner, 18 ... Capacitance load, 1
Reference numeral 9: resistive load, 20: charger, 21: charger before cleaner, 22: driven roller, 23: image forming medium, 24: driven roller, 25: gap, 31: shield member, 32: wire electrode, 33: guide Member, 34: resistor, 35: electric circuit, 36: switching element, 100: bias power supply.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tatsuo Igawa 4026 Kuji-cho, Hitachi City, Ibaraki Prefecture Hitachi, Ltd. Inside Hitachi Research Laboratory (72) Inventor Masato Miwa 2-6-1, Otemachi, Chiyoda-ku, Tokyo Hitachi, Ltd. (56) References JP-A-1-292378 (JP, A) JP-A-3-186876 (JP, A) JP-A-61-25171 (JP, A) JP-A-5-333704 (JP) , A) JP-A-3-186877 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/16 G03G 15/14 101

Claims (1)

(57) Claims: 1. A photoreceptor, a charger for charging the surface of the photoreceptor, and an exposure device for irradiating the surface of the photoreceptor with light in accordance with a desired image; A developing device that causes toner to adhere to the surface of the photoconductor by electrostatic force, a plurality of rollers, an endless belt-shaped transfer material transporting unit that stretches over the plurality of rollers, and transports the transfer material; An image forming apparatus having a transfer charger for transferring the toner on the surface of the photoreceptor to the transfer material by applying a charge having a polarity opposite to that of the toner and charging the transfer material transporting means, wherein the plurality of rollers are Transfer material supply section of transfer material transport means
And a roller provided in the transfer material peeling section,
The roller provided in the transfer material supply unit and the transfer material peeling unit
Of the rollers provided, peeling of the transfer material by the transfer material transporting means
An image forming apparatus comprising said that the application of a DC bias voltage of the same polarity as the transfer charger only rollers provided in the section.