JP3374545B2 - Sheet peeling device of sheet transport 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 sheet peeling device for peeling a sheet from a sheet conveying device which holds and moves a sheet such as paper like a transfer drum of a color copying machine by using peeling start means such as a claw. Regarding

[0002]

2. Description of the Related Art Conventionally, in a multicolor image forming apparatus such as a color copying machine or a color printer, a transfer drum holds a sheet such as paper and rotates it. Then, this rotation is continued, and each time the sheet passes the photoconductor drum which is close to the transfer drum, the toner image is transferred to the sheet one color at a time, and the color toner image is obtained by transferring the toner image a plurality of times. Normally, only one photosensitive drum is provided in one device, and toner images of different colors are formed four times on the photosensitive drum while the transfer drum is rotated, for example, four times. The toner image is transferred onto the sheet. In general, a sheet is attracted to a transfer drum by static electricity, and various proposals have been made up to now for peeling the sheet on which a toner image has been transferred from the transfer drum.

FIG. 14 is a perspective view showing a conventionally used transfer drum 1 and a peeling device for peeling a sheet (sheet) from the transfer drum 1. A device similar to this device is disclosed in JP-A-4-31.
It is disclosed in Japanese Patent No. 3783. The transfer drum 1 is provided with circular flanges 2 and 4 arranged on both sides, a tie plate 6a arranged between these flanges 2 and 4, and a cylindrical film material 7. The membrane material 7 is made of a plastic film, both sides of which are fixed to the flanges 2 and 4, respectively, the inner peripheral surface of the front end is fixed to the front end plate 6a, and the inner peripheral surface of the rear end is fixed to the rear end plate 6b. ing. Front end plate 6a and rear end plate 6b
Is fixed to the tie plate 6c. The transfer drum 1 is adapted to rotate around a central axis 5.

A peeling claw unit 20 is arranged near the transfer drum 1. The peeling claw unit 20 is configured to rotate around a support shaft 22 parallel to the transfer drum 1. A claw holding plate 21 is attached to the support shaft 22, and the claw member 30 is attached to the claw holding plate 21.
~ 34 are fixed at intervals. Of these claw members 30 to 34, the central claw member 30 (peeling start means)
Is formed longer than the other claw members 31 to 34.
Then, the front end plate 6 is made to correspond to the central claw member 30.
A hole 8 is formed in a. When the sheet is peeled off, the claw member 30 enters the hole 8.

A recess 3 is formed on the outer peripheral surface of the flange 2 on the right side of the drawing. On the other hand, the claw holding plate 2
A roller 25 is formed on a side portion of the roller 1, so that the roller 25 can enter the concave portion 3 while the transfer drum 1 is rotating. An arm 23 is arranged between the support shaft 22 of the claw holding plate 21 and the roller 25, and the arm 23 projects laterally. One end of a spring 26 is hooked on the arm 23, and the other end of the spring 26 is connected to a core of a solenoid 27. When turned on, the solenoid 27 pulls the core downward, thereby lowering the spring 26 and the arm 23 and rotating the pawl holding plate 21 clockwise in the drawing. Then, as the claw holding plate 21 rotates, the roller 25 enters the concave portion 3 formed at the end portion of the transfer drum 1, and at the same time, the transfer drum 1
The claw member 30 enters the hole 8 in the center of the. A roller 35 is rotatably attached to the tip of the claw member 30.

As shown in FIG. 15A, a flip-up member 10 for covering the hole 8 is arranged in the front end plate 6a. The flip-up member 10 is a thin film having large elasticity such as a plastic film. Then, the base portion 11 of the flip-up member 10 is attached to the surface of the front end plate 6a on the rotation direction side of the transfer drum 1 with respect to the hole 8. Further, the rear end portion 12 of the flip-up member 10 is on the side opposite to the rotation direction of the transfer drum 1 with respect to the hole 8, and the front end plate 6
It is placed on the film material 7 on a.

The sheet P is adsorbed on the film material 7 of the transfer drum 1 by static electricity (shown by an imaginary line in FIG. 14). Here, the front end of the paper sheet P is placed on the rear end portion 12 of the flip-up member 10. The transfer drum 1 contacts a photoconductor drum (not shown), and the toner image formed on the photoconductor drum is transferred to the paper P on the transfer drum 1. Then, for example, the transfer drum 1 is rotated four times, and toner images of different colors are transferred onto the paper P four times by the photosensitive drum.

When the transfer of the toner images of a plurality of colors is completed in this way, the paper P is peeled off by the peeling claw unit 20. In this case, after the transfer of the final toner image, the solenoid 27 shown in FIG. 14 is turned on while the front end of the paper P reaches the peeling claw unit 20 as the transfer drum 1 rotates, and the claw holding plate is turned on. 21 is pulled clockwise. At this point, the front end of the longest central claw member 30 is still in a position away from the transfer drum 1, as shown in FIG. After that, the roller 25 provided on the claw holding plate 21 enters the recess 3 formed on the outer peripheral surface of the flange 2. At this time, as shown in FIG. 15B, the claw member 30 enters the hole 8 of the front end plate 6 a of the transfer drum 1, and the roller 35 pushes the flip-up member 10 in the direction of entering the hole 8. As a result, the flip-up member 10 bends, the rear end 12 separates from the front end plate 6a, and the front end of the paper P is flipped up.

As the front end of the paper P is flipped up in this manner, the longest claw member 30 enters under the paper P and begins to peel the paper P from the film material 7. After that, the other claw members 31 to 34 enter between the paper P and the film material 7,
These jointly peel off the paper P. When the transfer drum 1 further rotates and the roller 25 comes out from the recessed portion 3, the claw holding plate 21 rotates clockwise. As a result, the claw member 30 and the claw members 31 to 34 separate from the transfer drum 1 and do not come into contact with the film material 7 thereafter, as shown in FIG.

[0010]

However, since this peeling device is provided with the flip-up member 10, the number of parts increases and the cost also increases. Also, the flip-up member 1
There is also a demand for strict accuracy in the position where 0 is provided. That is, as shown in FIGS. 14 and 15, the rear end portion 12 of the flip-up member 10 must overlap the film material 7. This is because when the flip-up member 10 does not overlap the film material 7 as shown in FIG. 16 (A), the claw member 30 contacting the flip-up member 10 then contacts the front end of the film material 7, Because it will peel off.

On the other hand, as the overlapping length of the flip-up member 10 and the film material 7 is larger, the space 16 between the paper P and the film material 7 shown in FIG. Will be formed. As described above, the paper P is attracted to the film material 7 by the action of static electricity, but when the space 16 becomes large, the front end of the paper P is not stable, and when the paper P comes into contact with the photoconductor drum for transferring the toner image. It rises from the film material 7 and causes paper wrinkles and paper jams. Further, the transfer of the toner image is also performed by adsorbing the charged toner particles on the photosensitive drum to the paper P by the action of the electric field, but the space 16 acts on this electric field as an insulator, and the toner particles are transferred to the paper. It may not be adsorbed by P. When the area where the flip-up member 10 and the film material 7 overlap is large, an area where the toner particles are not adsorbed exists near the center of the paper P. Therefore, the shorter the overlapping length of the flip-up member 10 and the film material 7, the more preferable.

Further, when the front end of the paper P is flipped up, the toner particles transferred to this portion scatter, and the density of the image is lowered. Further, in order to cause the flip-up member 10 to be largely bent by the claw member 30 so that the paper P is sufficiently lifted from the film material 7, it is necessary to insert the roller 35 at the front end of the claw member 30 deeply into the hole 8 ( See FIG. 15B). Therefore, in practice, an inner push lever 36 that pushes the film material 7 outward from the inner circumference of the transfer drum 1 is provided.
When the claw member 30 rotates toward the transfer drum 1 as described above, it is necessary to rotate the internal push lever 36 in the clockwise direction in FIG. 15B. And this internal push lever 36
As a result, the number of parts increased and the manufacturing cost also increased.

Further, when the flip-up member 10 is provided on the flat film member 7 as shown in FIG. 15, since the front end of the paper P is placed on the flip-up member 10, the paper P The upper part of the flip-up member 10 rises and the front end of the paper P becomes unstable. Therefore, when the toner image is brought into contact with the photoconductor drum, the paper material is lifted from the film material 7 to cause paper wrinkles and paper jams. In order to prevent this, as shown in FIG. 17, the front end plate 6a is shortened, and the suction assisting member 37 is provided, so that the suction assisting member 3 is provided.
7 is provided with a concave portion 38, and a portion of the film material 7 that overlaps the flip-up member 10 is placed so that the portion of the flip-up member 10 on the film material 7 is at the same height as the other portion of the film material 7. I had to. In this figure, reference numeral 39 indicates a window formed for electrostatic attraction of the paper P to the film material 7 and electrostatic attraction of the toner to the paper P. Providing such an adsorption assisting member 37 further increases the manufacturing cost. Even if the window 39 is provided, it is inevitable that the adsorbability of the front end of the sheet P and the adsorbability of the toner to the sheet P are deteriorated.

The present invention has been made in consideration of the above circumstances, and it is possible to reduce the number of parts, do not require strict dimensional accuracy, and improve sheet retainability, transportability, and image quality. An object of the present invention is to provide a sheet peeling device for a simple sheet conveying device.

[0015]

Means for Solving the Problems In order to solve the above-mentioned problems, a sheet peeling apparatus according to the present invention peels a sheet from a sheet conveying device in which a film material is stretched around the outer periphery and the sheet adheres to the film material and rotates. And a peeling start means that is arranged so as to be able to contact the sheet attached to the film material and that starts peeling the sheet from the film material.
Is partially concave with respect to the surface to which the sheet is attached.
It has an approaching part made up of
At least the tip portion of the membrane material and the concave approaching portion of the membrane material
The concave approaching part so that it can enter between the front end of the
Is formed .

[0016]

In the present invention, the peeling start means is inserted between the sheet and the concave approaching portion of the film material. Once the peeling start means has entered between the sheet and the film material, the sheet and the film material are peeled off by the peeling start means or another member as the sheet conveying device moves.

Here, at least the tip of the peeling starting means
Part can enter between the concave approaching part of the membrane material and the front edge of the sheet.
It is possible to start the peeling of the sheet and the film material by the peeling start means simply by forming the concave approaching portion , so that the flip-up member 10, the internal push lever 36,
Parts such as the suction assisting member 37 are unnecessary. Therefore, the number of parts can be reduced and the manufacturing cost can be reduced. Further, it is possible to eliminate the above-described deterioration of the toner adsorbability due to the provision of the flip-up member and the adsorption assisting member. In addition, while the flip-up member is required to have strict dimensional accuracy, there is a large tolerance in the size of the concave approaching portion of the film material, which is easy to form and the manufacturing cost can be reduced.

As one aspect of the present invention, the approaching portion
Other than the above, the position control made of a soft material on the lower surface of the film material.
Control member is arranged, and the film material other than the approaching portion is connected to the seal member.
The width may be flat in the width direction. According to this
It is possible to make the portion of the seat that overlaps the approaching portion and the portion that does not overlap the same portion have the same height. Therefore, when the conveying unit is a transfer roll of the image forming apparatus and is pressed against an image carrier such as a photoconductor drum and the sheet is passed through a nip between the image carrier and the transfer roll, the sheet is transferred from the transfer roll. It is possible to prevent the sheet from floating and causing wrinkles in the sheet, and preventing the sheet from being jammed in the nip. Furthermore, when the transporting means is a transfer roll of the image forming apparatus, it is possible to eliminate the above-mentioned toner scattering and toner adsorption deterioration due to the provision of the flip-up member and the suction assisting member. Therefore, the quality of the formed image can be improved.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. In the figure, the same reference numerals are given to the portions corresponding to the respective portions in FIG. (1) First Embodiment A. First Embodiment FIG. 1 is a sectional view showing a transfer portion of a color copying machine to which a sheet peeling device according to a first embodiment of the present invention is applied. In the figure, reference numeral 15 indicates a photoconductor drum, and the photoconductor drum 15 is arranged so as to be in contact with the transfer drum (sheet conveying device) 1. In the figure, the transfer drum 1 is rotated counterclockwise and the photoconductor drum 15 is rotated clockwise, so that the paper P is passed between them. The sheet P is guided by the guide 40, passes between the registration rolls 41, 41, and is pressed by the opposing roll 42 to be brought into contact with the surface of the transfer drum 1. An adsorption corotron 43 is provided inside the transfer drum 1 at a position facing the opposing roll 42, and the sheet P is adsorbed to the film material 7 by the static electricity generated by the adsorption corotron 43.

Around the photosensitive drum 15, a plurality of toner image forming devices (not shown) are arranged, and each toner image forming device forms a toner image for each color on the surface of the photosensitive drum 15. Then, the toner image on the photoconductor drum 15 is transferred onto the paper P on the transfer drum 1 in the area where the photoconductor drum 15 and the transfer drum 1 are in contact with each other. In this embodiment, the transfer drum 1 is rotated four times while the paper P is being attracted to the transfer drum 1, and toner images of different colors are formed on the photosensitive drum 15 four times during this time, and each time the transfer drum 1 is rotated once. By transferring the toner image onto the paper P, a color toner image is formed on the paper P.

In order to transfer the toner image on the surface of the photosensitive drum 15 onto the paper P, a transfer corotron 44 which forms an electric field for attracting toner is arranged inside the transfer drum 1. The reference numeral 45 represents the transfer drum 1 and the photosensitive drum 1.
5 shows a transfer baffle that blocks the electric field so that the transfer of toner does not start on the upstream side of the contact area with 5.

After the transfer of the toner images of plural colors is completed, the paper P
Is peeled off by a peeling claw unit 20 similar to that shown in FIG. 14, and thereafter, it is conveyed along a guide 47 by a mechanism (not shown) and sent to a fixing device that fixes the toner image on the sheet P. A peeling corotron 46 is arranged upstream of the peeling claw unit 20 and outside the transfer drum 1 in order to easily peel the paper P from the transfer drum 1.
As a result, the static electricity given by the adsorption corotron 43 is removed. Further, at a position downstream of the peeling claw unit 20 and upstream of the adsorption corotron 43, an inner charge-eliminating corotron 48 and an outer charge-eliminating corotron 49 are disposed, whereby the film material 7 is completely neutralized, The next paper P can be sucked by the suction corotron 43.

FIG. 2 shows a transfer drum 1 and a peeling claw unit 2.
It is a perspective view which shows 0. Similar to the transfer drum of FIG. 14, the transfer drum 1 is formed into a cylindrical shape with circular flanges 2 and 4 arranged on both sides and a tie plate 6c arranged between these flanges 2 and 4. The film material 7 is provided. The membrane material 7 is made of a plastic film, both sides of which are fixed to the flanges 2 and 4, respectively, the inner peripheral surface of the front end is fixed to the front end plate 6a, and the inner peripheral surface of the rear end is fixed to the rear end plate 6b. ing. Front end plate 6
The a and the rear end plate 6b are fixed to the tie plate 6c. The transfer drum 1 is adapted to rotate around a central axis 5.

A peeling claw unit 20 similar to that shown in FIG. 14 is arranged near the transfer drum 1. Also in this embodiment, the longest central claw member 30 of the claw members 30 to 34 of the peeling claw unit 20 is the paper P.
It is used as a means for starting peeling. Further, in order to rotate the peeling claw unit 20 in the clockwise direction in the drawing when the paper P is peeled, the solenoid 27, the roller 25, the concave portion 3 and the like are provided as in the above.

Now, unlike the prior art shown in FIG. 14, a pair of slits 50, 50 are formed at the front end of the film material 7. These slits 50, 50 are provided on both sides of a position (hereinafter referred to as an approaching portion) 51 corresponding to the claw member 30, and are formed parallel to the circumferential direction of the transfer drum 1, that is, the direction in which the film material 7 advances. ing. 3 and 4
Shows the slits 50 and the vicinity of 50 in an enlarged manner. On the backside outside the slits 50, 50 at the front end of the film material 7,
A thin plate-shaped position regulating member (position regulating means) 52 is attached, and the position regulating members 52, 52 are attached to the front end plate 6.
It is attached to a. On the other hand, the approaching portion 51 is directly attached to the front end plate 6a. Although a double-sided tape is simple and preferable as a means for attaching, it is not limited to this as long as it does not deteriorate the film material 7 or the position regulating member 52.

As described above, the position restricting member 52 smoothes the portion of the film material 7 other than the approaching portion 51 in the axial direction of the transfer drum 1, and only the approaching portion 51 is located on the inner peripheral side of the other portions. It is supposed to be arranged. When the sheet P is sucked onto the film material 7 by the suction corotron 43, the front end of the sheet P is overlapped with the slits 50, 50 so as to overlap the approaching portion 51, whereby the front end of the sheet P approaches. A gap S is provided between the portion 51 and the portion 51.

As will be described later, the claw member 3 is provided in this gap S.
The front end of 0 enters and the paper P starts to be peeled from the film material 7. Since the other claw members 31 to 34 come into contact with the portion of the film material 7 other than the approaching portion 51 from the outside after the claw member 30 has entered, the position regulating member 52 is formed of a soft material such as sponge. And preferred.

B. Operation of the Embodiment Next, the operation of this embodiment will be described. First, Fig. 1
The transfer roller 1 rotating counterclockwise in the direction of the registration roll 4 is guided by the guide 40.
The sheet P conveyed to 1 is conveyed and is pressed by the opposing roll 42 and brought into contact with the transfer drum 1. And paper P
Is attracted to the film material 7 of the transfer drum 1 by the electric field of the adsorption corotron 43. At this time, as shown in FIG. 3, the front end of the paper P is engaged with the slits 50, 50 and overlaps the approaching portion 51.

The sheet P attracted to the transfer drum 1 passes through the nip between the transfer drum 1 and the photosensitive drum 15.
At this time, the toner image formed on the surface of the photoconductor drum 15 is transferred onto the paper P by the action of the transfer corotron 44. A toner image is transferred one color at a time as the paper P passes through the nip. For example, when four color toner images are combined to form a color image, one paper P is rotated four times. Then, after the transfer of the toner image for the fourth time is completed and the front end of the paper P reaches the peeling claw unit 20, as shown in FIG.
The solenoid 27 shown in is turned on, the claw holding plate 21 is pulled in the clockwise direction, and the roller 25 contacts the outer peripheral surface of the flange 2. At this point, the front end of the longest central claw member 30 is still in a position away from the transfer drum 1. At approximately the same time, the peeling corotron 46 removes the static electricity provided by the adsorption corotron 43, and the paper P
Is easily peeled off.

After that, the roller 25 enters the recess 3 formed on the outer peripheral surface of the flange 2. At this time, as shown in FIG. 4, the tip portion of the claw member 30 comes into contact with the approaching portion 51 of the film material 7. Then, as the transfer drum 1 rotates, the claw member 30 causes a gap S between the front end of the paper P and the approaching portion 51 of the film material 7.
To contact the front end of the paper P from the inside and start peeling the paper P from the film material 7. Following this, the claw members 31 to 31
4 contacts the portion of the film material 7 other than the approaching portion 51 from the outside. Since the front end of the paper P is separated from the film material 7, these claw members 31 to 34 also enter between the film material 7 and the paper P. At this time, the position restricting member 52 is pushed by the claw members 31 to 34 and deforms, so that the claw members 31 to 34 easily enter between the film material 7 and the sheet P.

Thereafter, as the transfer drum 1 continues to rotate, the sheet P rides on the claw members 30 to 34 and the film material 7 is formed.
Is peeled off from. In addition, all the claw members 30 to 34
When the paper enters between the paper P and the film material 7, the roller 25 shown in FIG. 2 escapes from the concave portion 3, and the peeling claw unit 20 rotates clockwise. As a result, the claw member 30 separates from the transfer drum 1 to the outside and does not come into contact with the film material 7 thereafter. After that, the sheet P is conveyed along the guide 47 by a mechanism (not shown) and is sent to a fixing device that fixes the transferred toner image onto the sheet P. On the other hand, the solenoid 27 is turned off, the roller 25 is separated from the outer peripheral surface of the flange 2, and the film material 7 is discharged by the charge removing corotrons 48 and 49, so that the next sheet P can be conveyed.

In this embodiment, the pair of slits 50, 50 are formed in the film material 7 and the position regulating member 52 is simply provided, whereby the peeling of the sheet P and the film material 7 by the peeling claw 30 can be started. . Therefore, the parts such as the flip-up member 10 and the inner push lever 36 used in the conventional technique are unnecessary. Therefore, the number of parts can be reduced and the manufacturing cost can be reduced.

Further, as in the prior art, the flip-up member 1
When 0 is provided, the paper P is lifted by the flip-up member 10 and a space is created between the paper P and the film material 7, so that the toner adsorbability is lowered. Problems can be resolved. That is, here, the front end of the film material 7 is made substantially flat by the position regulating member 52, and the approach portion 5 directly attached to the position regulating member 52.
Only 1 is recessed. Therefore, the portion of the paper P that overlaps the approaching portion 51 and the portion that does not overlap have the same height. Therefore, it is possible to prevent the paper P from floating from the transfer roll 1 to cause wrinkles in the paper P or the paper P from being jammed in the nip.

In the film material 7, only the approaching portion 51 is not in close contact with the paper P, and the approaching portion 51 only overlaps the edge of the paper P. Therefore, unlike the conventional case, a space is formed on the center side of the paper P, and the toner adsorbability is not deteriorated here. Further, since the front end of the film material 7 is flat, it is not necessary to provide a member such as the suction assisting member 37 inside the paper P and the film material 7. Therefore, the number of parts can be further reduced, and
It is possible to solve the problem that the suction assisting member 37 partially blocks the electric field and thus the attraction of the paper P and the toner is lowered.

Furthermore, the paper P is lifted by the claw members 30 to 34 and gradually peeled off. Here, since the paper P is not subjected to the abrupt movement unlike the flip-up member, it is possible to prevent the toner from scattering. As described above, since the toner adsorbability is not deteriorated and the scattering can be prevented, the quality of the formed image can be improved.

Here, as long as the slits 50, 50 have a length slightly larger than that of the position regulating member 52 as shown in FIGS. 3 and 4, the approaching portion 51 has the other portion of the film material 7. The inner side of the claw member 30 is closer to the sheet P and the approaching portion 51.
It becomes possible to break in between. Also, the slit 5
The interval between 0 and 50, that is, the width of the approaching portion 51 may be slightly larger than the width of the claw member 30. Slit 5 like this
There is a large tolerance for 0,50 dimensions. Therefore, it is easy to form and the manufacturing cost can be reduced.

C. Modifications FIGS. 5 and 6 show modifications of the first embodiment. In the first embodiment, the gap S is provided between the sheet P and the approaching portion 51 by providing the position regulating member 52, but in this modification, the front end plate 6a is used as the position regulating means for providing the gap S. ing. That is, the outer surface of the approaching portion 51 is opposed to the inner peripheral side of the front end plate 6a, and the inner surface of the portion other than the approaching portion 51 of the film material 7 is attached to the outer peripheral side.

As a result, it is not necessary to provide the position regulating member 52, and the number of parts can be reduced.
Further, since the front end plate 6a is sandwiched between the approaching portion 51 and the other portion, the front end of the claw member 30 does not attach the film material 7 even if the approaching portion 51 is not attached to the front end plate 6a. It is possible to avoid the possibility of breaking through. The front end of the claw member 30 is the slit 5 of the front end plate 6a.
In order to prevent contact with a portion between 0 and 50, it is more preferable to make this portion thin like the front end plate 6a shown in FIG. 8 described later, for example.

(2) Second Embodiment A. Configuration and Operation of Embodiment FIG. 7 shows a second embodiment of the present invention. Here, slits 60, 60 are formed slightly rearward of the front end of the film material 7, and the front end of the film material 7 extends to the tie plate 6c. Similar to the first embodiment, these slits 60, 6
0s are provided on both sides of a position (hereinafter referred to as an approaching portion) 61 corresponding to the claw member 30, and are formed parallel to the circumferential direction of the transfer drum 1, that is, the direction in which the film material 7 advances.
In the front end portion of the film material 7, the portion other than the approaching portion 61 is attached to the tie plate 6c, or the position regulating member 52 similar to that of the first embodiment is attached. 52 is attached to the front end plate 6a. On the other hand, the approaching portion 61 is directly attached to the front end plate 6a.

Also in the second embodiment, the tip of the claw member 30 enters between the paper P and the approaching portion 61, and the peeling of the paper P is started. As a result, the same effect as that of the first embodiment is achieved.

B. Modified Example FIG. 8 shows a modified example of the second embodiment. In this modification, the front end plate 6a is used as a position regulating means for providing the gap S, the front end plate 6a is inserted into the slits 60, 60, and the outer surface of the approaching portion 51 is opposed to the inner peripheral side of the front end plate 6a. The inner surface of the portion other than the approaching portion 51 of the film material 7 is attached to the outer peripheral side.

As a result, it is not necessary to provide the position regulating member 52, and the number of parts can be reduced.
Further, since the front end plate 6a is sandwiched between the approaching portion 51 and the other portion, the tip of the claw member 30 may break through the film material 7 without attaching the approaching portion 51 to the front end plate 6a. Still not. In order to prevent the tip of the claw member 30 from coming into contact with the portion between the slits 60 of the front end plate 6a, the recess 6 is formed in this portion.
d is formed and is made thin.

(3) Third Embodiment A. Configuration of Embodiment FIG. 9 shows the transfer drum 7 according to the peeling device of the third embodiment.
It is sectional drawing which shows the film material 7 of No. 1, and FIG.10 and FIG.11 is the figure which expanded the A section of FIG. Although only the film material 7 is shown in FIG. 9, it goes without saying that the film material 7 is supported by the flanges 2 and 4 to have a cylindrical shape as shown in FIG. Further, the peeling claw unit 20 and the corotrons 43, 44, 46, 48, 49 of FIG.

In this embodiment, the front end plate 6
a, the rear end plate 6b, and the tie plate 6c are not provided, and the front end and the rear end of the film material 7 are, for example, a double-sided tape 72.
It is directly attached by. In this case, the rear end is outside the front end, that is, on the peeling claw 30 side. As shown in FIG. 10, the slits 50, 50 similar to those in the first embodiment are formed at the front end of the film material 7.
The space between them is an approaching portion 51 of the claw member 30 that approaches.

Here, the film material 7 is formed into a cylindrical shape by the flanges 2 and 4 (position regulating means) shown in FIG. 2 except for the front end portion. Therefore, as shown in FIG. 11, the front end of the film material 7 is sunk into the inside of the rear end by keeping the other end of the film material 7 having a uniform curvature. A step is formed between the sheet and the approach portion 51 and the paper P.
The gap S between

B. Operation of Embodiment In this embodiment as well, similarly to the first embodiment, the claw member 30 of the peeling claw unit 20 enters the gap S and starts peeling the paper P. In addition, here, not only the approaching part 51,
Since all the front ends of the film material 7 are also made to go under the rear end in the same manner, the front end of the paper P is covered with the film material 7 over the entire width direction.
From the front end and the paper P except the approaching portion 51.
There is also a gap S between and. Therefore, the other claw members 31 to 34 can also easily enter between the paper P and the film material 7.

Since the front end plate 6a, the rear end plate 6b and the tie plate 6c are not provided here, the number of parts can be further reduced and the manufacturing cost can be reduced.

(4) Fourth Embodiment FIGS. 12 and 13 show the essential parts of a fourth embodiment of the present invention. Here, the front end and the rear end of the film material 7 are connected by a tie plate (position regulating means) 6c. Slits 50, 50 similar to those in the first embodiment are formed at the front end of the film material 7, and an approaching portion 51 is formed between the two.

Here, the inner surface of the portion other than the approaching portion 51 at the front end of the film material 7 is attached to the outer surface of the tie plate 6c, and the outer surface of the approaching portion 51 is disposed on the inner surface of the tie plate 6c. On the other hand, the inner surface of the rear end of the film material 7 is attached directly to the outer surface of the tie plate 6c or to the outer surface of the front end of the film material 7 except the approaching portion 51. Thus, without providing the front end plate 6a and the rear end plate 6b, the front end and the rear end of the film material 7 are connected only by the tie plate 6c, and at the same time, the large gap S between the approaching portion 51 and the sheet P is formed. Can be provided. Here, by using the tie plate 6c, it is possible to prevent the front end and the rear end of the film material 7 from bending in an unexpected direction and prevent the inconvenience that the claw member 30 sticks in here.

In all of the above-mentioned embodiments, the peeling claw unit 20 is provided with one longest claw member 30, and the slits 50, 50 or 6 are correspondingly provided.
0 and 60 are provided for each pair. However, without being limited to this, for example, when the above-mentioned sheet peeling device is applied to a transfer drum that conveys a paper P having a large width, a plurality of long claw members 30 are provided and a plurality of pairs of slits are provided correspondingly. It is also possible to form.

[0051]

As described above, according to the first aspect of the invention, at least the tip of the peeling initiation means is a film material.
It is possible to enter between the concave approaching part of the
In addition, since it is possible to start the peeling of the sheet by the peeling starter only by forming the concave approaching portion , it is possible to reduce the number of parts. Further, since the sheet can be peeled off if the sheet overlaps the approaching portion of the film material and the peeling start means can enter between the sheet and the approaching portion , the dimensional accuracy of the recessed approaching portion of the film material becomes strict. It is not necessary, is easy to manufacture and can reduce costs.

Further, according to the invention of claim 3 ,
Be sure to hold and convey the sheet by the sheet conveying means.
And when applied to an image transfer device
It is possible to improve the image quality.

[Brief description of drawings]

FIG. 1 is a sectional view showing a transfer portion of a color copying machine to which a sheet peeling device according to a first embodiment of the present invention is applied.

FIG. 2 is a perspective view showing the overall configuration of the sheet peeling device of the first embodiment.

FIG. 3 is a perspective view showing a main part of the sheet peeling device of the first embodiment.

FIG. 4 is a sectional view taken along the line IV-IV of FIG.

FIG. 5 is a perspective view showing a main part of a modified example of the first embodiment.

6 is a sectional view taken along the line VI-VI of FIG.

FIG. 7 is a perspective view showing a main part of a sheet peeling device according to a second embodiment of the present invention.

FIG. 8 is a perspective view showing a main part of a modified example of the second embodiment.

FIG. 9 is a cross-sectional view showing a film material of a transfer drum according to a sheet peeling device of a third embodiment of the invention.

FIG. 10 is a perspective view showing a portion A in FIG.

11 is a cross-sectional view showing a portion A in FIG.

FIG. 12 is a perspective view showing a main part of a sheet peeling device according to a fourth embodiment of the present invention.

13 is a sectional view taken along the line XIII-XIII in FIG.

FIG. 14 is a perspective view showing an overall configuration of a conventional sheet peeling device.

FIG. 15 is a cross-sectional view showing a sheet peeling process in a conventional sheet peeling apparatus.

FIG. 16 is a plan view showing a defective product of a conventional sheet peeling device.

FIG. 17 shows another example of a conventional sheet peeling device, (A) is a plan view and (B) is a side sectional view.

[Explanation of symbols]

1,71 Transfer drum (sheet conveying device), 2,4 Flange (position regulating means), 6c tie plate (position regulating means), 6a front end plate (position regulating means), 7 film material, 15 photosensitive drum, 20 peeling Claw unit, 30
Claw member (peeling start means) 31 to 34 Claw member, P
Paper (sheet), 50, 60 Slit, 51, 61
Approaching part, 52 Position regulating member (position regulating means), S gap.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-313783 (JP, A) JP-A-5-61363 (JP, A) Fukuihei 1-71779 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B65H 41/00 G03G 15/00 516 G03G 15/14 101

Claims (3)

(57) [Claims] 1. A device for peeling a sheet from a sheet conveying device, wherein a film material is stretched around an outer periphery and the sheet adheres to the film material, and is rotated, and is arranged so as to come into contact with the sheet adhered to the film material. A peeling start means for starting peeling the sheet from the film material
The film material is partially provided on the surface to which the sheet is attached.
It has an approaching portion formed in a concave shape, and at least the tip portion of the peeling start means has the above-mentioned film material.
It can enter between the concave approaching part and the front edge of the sheet.
As described above, the sheet peeling device of the sheet conveying device , wherein the concave approaching portion is formed . 2. The concave approaching portion is the width of the sheet.
The sheet stripping apparatus according to claim 1, wherein the sheet stripping apparatus is formed substantially at the center of the film material . 3. A soft surface on the lower surface of the film material other than the approaching portion.
A position regulating member made of a material is arranged,
Flatten the film material other than in the width direction of the sheet
The sheet peeling apparatus according to claim 1, characterized in that.