JP3364528B2 - Transfer transfer device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer / conveying apparatus which can be applied to a facsimile, a printer or the like which adopts the PPC electrostatic transfer system.

[0002]

2. Description of the Related Art In a facsimile, printer or the like which employs a PPC electrostatic transfer system, a photosensitive member, a transfer belt which is an endless transfer means stretched by a driving roller and a driven roller and having a predetermined electric resistance value, There is a transfer conveyance device including a charge applying unit that applies an electric charge to the transfer belt and a cleaning unit that cleans the surface of the transfer belt.

FIG. 15 shows an example of the transfer / transport device. In FIG. 15, reference numeral 100 denotes a transfer belt as a transfer unit, which is arranged so as to face a drum-shaped photosensitive member 101 that rotates in the direction of the arrow. Transfer belt 100
Is supported between the driving roller 101 and the driven roller 102 and is rotated in the direction of the arrow, and is in contact with the back side of the belt at a position downstream from the portion facing the photoconductor. A transfer bias roller 103 is provided as a charge applying unit for applying an electric charge to the belt. Further, a transfer cleaning blade 104 as a cleaning means for cleaning the surface of the belt is provided so as to be in contact with the driven roller 102.

The transfer process is as follows. The photosensitive member 99 having a toner image formed on its surface rotates and moves, and the paper waiting at the registration roller 105 is sent out at a timing such that the leading end of the paper and the leading end of the toner image coincide with each other at the transfer unit.

A transfer bias is applied to the transfer bias roller 103 at the timing when the leading edge of the sheet enters the nip portion formed at the contact portion between the photosensitive member and the transfer belt, and on the transfer belt, the transfer bias is applied on the photosensitive member. Transfer is performed by applying a voltage having a polarity opposite to that of the toner. At this time, the sheet is electrostatically adsorbed on the transfer belt, so that the sheet is separated from the photoconductor and is carried on the transfer belt. This sheet of paper is subjected to curvature separation at the portion of the driven roller 102 and is sent to a fixing unit (not shown).

On the other hand, the toner remaining on the transfer belt is scraped off by the transfer cleaning blade 104 under the transfer belt. The toner remaining on the photoconductor is scraped off by the photoconductor cleaning unit, and the process proceeds to the next image forming step.

[0007]

[Problems to be Solved by the Invention] In the transfer / transport device, in order to secure cleaning performance of the transfer belt, transfer cleaning blade width ≧ transfer belt width. On the other hand, due to the dimensional tolerance of the structure that constitutes the transfer / transport device, that is, the dimensional tolerance of the processed article itself and the assembling of the article, deterioration of the transfer belt over time, environmental changes, etc., it is inevitable that the transfer belt meanders or shifts. It occurs as a strange phenomenon.

As a result, since the end portion of the transfer belt contacts the cleaning blade, the blade is likely to be turned over. If the blade is turned upside down, the blade is pressed against the transfer belt with an excessive force, the drive load increases, and the drive system is damaged. Also, by flipping over, the surface of the transfer belt is in a poor cleaning state.

[0009]

[0010]. The width of the cleaning means is as described above. In order to solve the above problem, when the transfer belt is set within the meandering range, the entire surface of the transfer belt cannot be cleaned.

For example, if the transfer belt width is 330 mm and the effective image area width is 297 mm (A4 width), it may be possible to set it so that there is no problem if the effective image area width 297 mm is completely cleaned.
Actually, when the blade width is set to 297 mm, the toner scattered on both outer sides of the effective image area width adheres to both ends of the transfer belt in the width direction, and is scattered again to contaminate the inside of the machine such as a facsimile or a printer.

Alternatively, in the above-described transfer / transport device, the toner scattered on the uncleaned area on the transfer belt, in other words, on the end portion of the transfer belt, causes paper jam at the transfer belt portion,
When a so-called jam occurs, there is a possibility that the user's hand or clothes thrust into the machine to recover the jam may be soiled, or the scattered toner may float again in the sealed machine to contaminate the machine.

Therefore, it is desirable to clean the entire surface of the transfer belt. However, since the purpose of cleaning in the non-image area is to prevent scattered toner and to prevent stains on hands and clothes when removing jams, cleaning performance in the effective image area (297 mm) is not required, Cleanability is required so that the blade does not turn over.

[0014] than this, in the invention of claim 1 to claim 4, when di catcher beam processing, and to provide a transfer conveying device which does not pollute the user's hand or clothes are plunged in flight.

[0015]

In order to achieve the above object, the present invention is configured as follows. (1). It is stretched between the photoconductor and the drive roller, and
Endless transfer means having air resistance, and this transfer means
Cleans the surface of the transfer means and the charge application means that applies the charge
The transfer and transport device equipped with
The cleaning means is arranged in the stretching direction of the transfer means.
The width in the direction orthogonal to the width is less than or equal to the width of the transfer means.
No. 1 cleaning member and the first cleaning member
Is provided on at least one end side of the
It protrudes to the outside of the end of the first cleaning member, and
The transfer member is different from the first cleaning member.
A second cleaning member that abuts in the state of
The second cleaning member is the first cleaning member.
The first cleaning unit is made of a material different from that of the member.
Harder than material, or lower in friction coefficient (claim
Item 1). (2). The first cleaning member is attached to the transfer means.
Against the counter state, the second cleaning
The trailing member makes contact with the transfer means in the trailing state.
(Claim 2). (3). The second cleaning member is the first cleaning member.
Removable independently of the turning member (claim
3) . (4). The second cleaning member is the first cleaning member.
Contact angle to the transfer means more than the turning member
Reduces at least one of the contact pressures.
4) .

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

According to the present invention, the transfer cleaning blade as the cleaning means includes the first cleaning member mainly for cleaning the image portion and the first cleaning member.
By providing the second cleaning blades located on both sides of the cleaning member for mainly cleaning the non-image area, the second blade that is easily touched by clothes or the like during the jam processing is configured to be easily removable. It becomes possible.

[0023]

[0024]

【Example】

(1). FIG. 2 corresponding to claim 1 illustrates the structure of the transfer / transport device according to the present invention. The structure other than the characteristic part of the present invention conforms to the transfer / transfer device shown in FIG. In FIG. 2, the transfer belt 3
Is stretched by a driving roller 1 and a driven roller 2.
FIG. 1 shows a front view of the drive roller 1, and FIG. 4 shows a front view of the driven roller 2.

As shown schematically in FIG. 3, generally, when the roller 2'supporting the endless belt 3'is shaped like a drum, the belt 3'will have a large central portion during rotation. It has a tendency to approach, and can maintain stable running. In order to utilize this property, the driven roller 2 of the present example is also tapered at the end portion so as to maintain stability during traveling, as shown in FIG.

However, the traveling is not completely maintained in the center, and variations in parts are caused by dimensional differences such as parallelism between the driving roller 1 and the driven roller 2 and cylindricity of the transfer belt 3. The transfer belt 3 is generated, and the transfer belt 3 runs stably in a state slightly offset from the center of the transfer belt 3 to the front or rear.

Therefore, as shown in FIG. 2, a so-called counter cleaning blade system is used in which the tip of the cleaning blade 4 is in contact with the belt toward the upstream side in the rotating direction of the belt (see FIG. 5, reference numeral J in FIG. 5). Indicates the fulcrum axis.)
When cleaning the transfer belt surface with,
The width of the cleaning blade 4 is set so as to cover the effective image area width and be within the meandering range of the transfer belt 3,
Even if the transfer belt 3 is biased, the edge of the belt does not contact the blade edge.

In this example, as shown in FIG. 1, the width (W) of the cleaning blade 4 in the direction orthogonal to the stretching direction of the transfer belt 3 as the transfer means is set to the effective image area width (b ₁
= 297mm = width of A4 size) and more,
Width in the direction orthogonal to the stretching direction of the transfer belt (F = 330
mm) to the meandering width (b ₂ × 2 = 10 mm × 2 = 20 m) of the transfer belt in the direction orthogonal to the stretching direction of the transfer belt.
m minus the size (330 mm-20 mm = 310
mm) or less, that is, W = 306 mm in this example. In this example, the width of the transfer belt is (F = 330 mm)
And the condition of W ≦ F−b ₂ × 2 is satisfied.

In this example, since the width of the cleaning blade is set within the meandering range of the transfer belt, even if the transfer belt is deviated while the transfer belt is running, the end of the transfer belt contacts the edge of the cleaning blade. Since the blades are not turned over, problems such as an increase in driving load and damages to the drive system caused by the turned over blades do not occur.
Also, the cleaning failure caused by turning over is eliminated.

(2). In the example this example corresponding to claim 1, 2, 4, 6, 7, in the above example, both end portions of the cleaning blade 4 as a first cleaning member having a width dimension W = 306 mm The end cleaning blade 5-a as the second cleaning member,
I am wearing 5-b. The end portions of the end cleaning blades 5-a and 5-b project outward from the end portion of the cleaning blade 4.

Here, the edge cleaning blade 5-
The width b ₃ of each of a and 5-b is set to 24 mm, which is larger than the meandering width of 20 mm of the transfer belt.
The edge portion of the transfer belt is prevented from coming off from the edge cleaning blades 5-a and 5-b even when meandering by mm. A gap (Δt) of 0 to 0.5 mm is provided between the cleaning blade 4 and each of the end cleaning blades 5-a and 5-b in order to prevent the blades from overlapping with each other.

These end cleaning blades 5-
Reference characters a and 5-b are used for supplementary cleaning in a region having a small cleaning amount.
The same material as that, urethane rubber, is used, and as compared with the cleaning blade 4 as the first cleaning member, as shown in FIG. , The contact angle is set so that the contact is made in a state of being slanted. Alternatively, as shown in FIG. 9, compared to the case of the cleaning blade 4,
The compression spring 6 is contacted with the pressing force thereof being weakened.

In this way, when the condition setting that the contact angle of the second cleaning member is set to be negative or the pressing angle is weakened is selected, the same material as the first cleaning member is used as the first cleaning member. It can be applied to the second cleaning member. As a result, cleaning can be performed without the blade turning up.

Regarding the contact angle θ, as shown in FIG. 13, the end cleaning blade 5-a (5-b) is preferably θ = 4 ° to 16 ° with respect to the tangent line, and the optimum angle is θ. = 10 °. In this case, although the cleaning blade 4 is not shown, it is 20 ° with respect to the tangent line.
It is assumed that the inclination of is given.

In addition, as shown in FIGS. 10 and 11, so-called trailing in which the tip portions of the edge cleaning blades 7-a and 7-b are set to the downstream side in the rotational direction of the transfer belt. A cleaning blade method (see FIG. 5) is adopted. In FIGS. 10 and 11, the configuration of the portion other than the end cleaning blade is the same as the configuration shown in FIGS. 6 and 7.

This example and the following (3) to (4) will be described.
According to the above example, since the second cleaning member for cleaning the transfer belt surface is provided on both ends or at least one end side of the cleaning blade 4 under the condition different from the cleaning condition in the image area, The entire surface can be cleaned.

In the illustrated example, the end cleaning blades 7-a and 7- are provided at both ends of the transfer belt 3 in the width direction.
Although b are provided respectively, they are not necessarily provided at both ends in terms of preventing stains on the user's hand during jam processing and eliminating toner scattering due to contact with the user's hand.
At a minimum, when the user removes the jammed transfer paper, it is not necessary to soil the user's hand or clothes at the front end of the transfer belt, so at least the front side of the main body of the apparatus, which corresponds to the removal side, that is, It is sufficient to provide it on the side marked <Front> in the figure. There is an advantage that the toner scattering can be reduced even if it is not necessarily provided on the <back side>.

(3). Corresponding Description to Claim 3 In this example, based on the configuration of the blades shown in FIGS. 6 and 7, as shown in FIG. 12, the end cleaning blades 5-a, 5 are provided separately from the cleaning blade 4. −
b (or 7-a, 7-b) is provided, and these end cleaning blades can be independently attached to and detached from the transfer / conveying device main body 7 by the screw 8. Therefore, it is also interchangeable.

According to the experiment, the cleaning blade 4 is abraded by passing about 120,000 sheets of paper, causing cleaning failure and smearing on the back of the transfer paper. On the other hand, since the edge cleaning blades 5-a and 5-b (or 7-a and 7-b) are outside the effective image area width, there is no quality problem such as stain on the back of the paper. It was confirmed that it is not necessary to replace more than 120,000 sheets before the toner is scattered and the hand is soiled when the jam is removed. As described above, although the cleaning blades are replaced at different times, they can be replaced independently when necessary, which is economical.

In the illustrated example, the end cleaning blades 7-a and 7- are provided at both ends of the transfer belt 3 in the width direction.
b are provided respectively, but they are not necessarily provided at both ends, and at least when the user removes the jammed transfer paper, it is not necessary to stain the user's hand or clothes at the front end of the transfer belt. It suffices to provide it on at least the front surface of the apparatus main body, which corresponds to the above-mentioned removal side, that is, on the side labeled <front> in the drawing. Toner scattering can be reduced without necessarily providing it on the <back side>.

(4). Corresponding to claim 1 The material characteristics of the edge cleaning blades 5-a, b or 7-a, b in the above example are as follows:
Compared with, the one with higher hardness or the one with lower friction coefficient is used. Normally, urethane rubber having a hardness of 65 ° to 70 ° is used for the cleaning blade 4, and therefore urethane rubber having an hardness of 77 ° is preferably used.

Regarding the friction coefficient, when the friction coefficient of the cleaning blade 4 is 1.0 or less, the edge cleaning blades 7-a and 7-b are preferably 0.5 to 0.8, and the optimum. The value of is 0.8. As the material, a molded product obtained by mixing urethane rubber with a release agent such as fluorine or kiner is used.

As the second cleaning member, FIG.
As shown in FIG.
-In place of a, b or 7-a, b, a rotating brush 9-
It is also possible to provide a and b. When these rotating brushes are used, not only does the problem of blade turn-up do not occur, but there is an advantage that cleaning performance can be maintained over a drastically long period in terms of deterioration over time as compared with the case of a blade.

In the case of the rotary brush, assuming that the polarity of the toner is (+), the toner could be collected from the transfer belt 3 when a bias voltage of about -4 kv was applied to the rotary brush. Flicker bars 10-a, b fixed to a stationary member are provided on the outer peripheral portions of these rotating brushes.
Is abutted to scrape off the toner.

As described above, in this embodiment, the second cleaning member is made of a material different from that of the first cleaning member, and the material characteristic is made different from that of the first cleaning member, so that the belt curling occurs. Since difficult conditions are set, the desired cleaning performance can be achieved without causing the belt to be turned up.

In the illustrated example, the second cleaning members are provided at both ends of the transfer belt 3 in the width direction, but the second cleaning members are not necessarily provided at both ends, and at least the user removes the jammed transfer paper. Since it is not necessary to stain the user's hand or clothes at the front end of the transfer belt at this time, at least on the front side of the main body of the apparatus, that is, on the side indicated as <front> in the figure, which corresponds to the above removal side. Provision is sufficient. Toner scattering can be reduced without necessarily providing it on the <back side>.

[0047]

According to the first to fourth aspects of the present invention, it is possible to eliminate stains, toner scattering and the like caused by contact of the blade with the user's hand or clothes thrust into the machine when the blade is turned up or jammed. .

[0048]

[Brief description of drawings]

1 is a front view of a drive roller unit for explaining the dimensional relationship of transcriptional conveying device.

2 is a perspective view of a transcription conveying device.

FIG. 3 is a diagram illustrating a general method for preventing deviation of a belt.

FIG. 4 is a front view of the roller portion illustrating an example in which both end sides of a driven roller are tapered.

FIG. 5 is an explanatory view illustrating a contact method of a blade against a transfer belt.

6 is a perspective view of a transcription conveying device.

7 is a front view of a driving roller of the transcription unit.

FIG. 8 is a diagram illustrating a contact method of the second cleaning member with respect to the transfer belt.

FIG. 9 is a diagram illustrating a method of adjusting the contact force of the second cleaning member with respect to the transfer belt.

10 is a perspective view of a transcription conveying device.

11 is a front view of a driving roller of the transcription unit.

FIG. 12 is a perspective view of an essential part illustrating that the second cleaning member is attached to and detached from the main body independently of the first cleaning member.

FIG. 13 is a diagram illustrating a contact angle of the second cleaning member with respect to the transfer belt.

FIG. 14 is an explanatory diagram when a rotating brush is used as a second cleaning member.

FIG. 15 is a front view illustrating the configuration of the main part of a transfer / transport device applicable to the present invention.

[Explanation of symbols]

1 Driving Roller 2 Driven Roller 3 Transfer Belt 4 (as Transfer Means) Cleaning Blade 5-a (Cleaning Means, First Cleaning Member) End Cleaning Blade 5-b (as Second Cleaning Member) End cleaning blade 7-a (as the second cleaning member) End cleaning blade 7-b (as the second cleaning member) End cleaning blade 9-a (as the second cleaning member) Rotating brush 9-b (as second cleaning member)

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yuko Harazawa, Inventor Yuko Nakamamagome 1-3-6, Ota-ku, Tokyo, Ricoh Co., Ltd. (72) Inventor, Koichi Ishii 1-3-3 Nakamagome, Ota-ku, Tokyo (56) Reference JP-A-2-157769 (JP, A) JP-A-3-291685 (JP, A) JP-A-2-106780 (JP, A) Actual development Sho-57- 72455 (JP, U) Actual development 2-13262 (JP, U) Actual development Sho 62-146182 (JP, U) Actual development 1-73868 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/16-15/16 103 G03G 21/10-21/12

Claims (4)

(57) [Claims] 1. A photosensitive member is stretched by a driving roller and a predetermined member.
Endless transfer means having an electric resistance value of
The charge applying means for applying electric charge to the step and the surface of the transfer means are
In a transfer conveyance device equipped with cleaning means for cleaning.
In addition, the cleaning means is directly aligned with the stretching direction of the transfer means.
The width in the intersecting direction is less than or equal to the width of the transfer means.
The cleaning member and the first cleaning member are
It is provided at least on one end side, and the end is the first
Of the cleaning member of the
Different from the first cleaning member with respect to the copying means
The second cleaning member that abuts in a state of
The second cleaning member is the first cleaning member described above.
And a material different from that of the first cleaning member.
A transfer / conveyance device having a higher hardness or a lower friction coefficient . 2. The first cleaning member is the transfer hand.
Abutting against the step in the counter state, the second creep
The trailing member is in the trailing state with respect to the transfer means.
The transfer / conveyance apparatus according to claim 1 , wherein the transfer / conveyance apparatus abuts . 3. The second cleaning member is the first cleaning member.
The transfer / conveyance device according to claim 1 , wherein the transfer / conveyance device can be detached independently from the cleaning member . 4. The second cleaning member is the first cleaning member.
Contact angle with respect to the transfer means rather than the cleaning member
Alternatively, at least one of the contact pressures is small , and the transfer / conveyance device according to claim 1 .