JPH0690574B2 - Image forming device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image on a recording material carried on a recording material carrier, and then separating the recording material from the recording material carrier, and particularly to an image forming apparatus. A color image forming apparatus of a type in which a toner image of a plurality of colors formed on a carrier is superposed on the same recording material, that is, a transfer material to be suitably transferred, and then a transfer device for separating the transfer material is obtained. It can be suitably realized.

2. Description of the Related Art Conventionally, in an image forming apparatus, such as an electrophotographic copying apparatus, which forms a toner image on an image bearing member such as an electrophotographic photosensitive member and transfers the toner image to a transfer material to obtain an image,
A transfer device is provided to convey the transfer material to the image carrier carrying the toner image and bring the transfer material into contact therewith to transfer the toner image on the image carrier to the transfer material.

As shown in FIG. 11, the transfer device 10 includes a drum-shaped transfer material support 11 which is usually formed in a cylindrical shape, and a leading end portion of the transfer material P fed to the transfer material support 11. A transfer material locking portion 12 provided on the transfer material support 11 to stop and an opening 13 (indicated by a broken line) formed in the circumferential direction of the transfer material support 11
And a transfer material carrying sheet (dielectric sheet) 14 like a high resistance film, which is placed so as to carry the transfer material P.

With the above-described configuration, the transfer material P supplied to the transfer material support 11 moves in the up-and-down direction that constitutes the transfer material locking portion 12, and is moved by the locking claws (grippers) formed so as to lock the transfer material. And the subsequent portion of the transfer material P is supported on the transfer material carrying sheet 14. The transfer material P, which is firmly held by the gripper 12 and supported by the transfer material support sheet 14, is brought into contact with the image carrier as the transfer material support 11 rotates. The transfer material P is disposed inside the transfer material support 11 and is applied with a corona discharger that applies an electric charge having a polarity opposite to that of the toner to the back surface of the transfer material carrying sheet, or a voltage having a polarity opposite to the toner is used by using a conductive roller or the like. By applying, the toner image on the image carrier is transferred.

The transfer material P transferred by the above method is subjected to AC neutralization by a static eliminator (not shown) in order to weaken the attraction of the transfer material to the transfer material carrying sheet 14, and then the separation claw A is used as the transfer material. The transfer material was separated from the transfer material carrying sheet 14 by inserting it between the transfer material carrying sheets. At this time, a transfer material push-up member (not shown) may be provided in the grip 12 in order to facilitate the separation claw A to enter between the transfer material and the transfer material carrying sheet.

As described above, in the conventional transfer device in the image forming apparatus, the transfer material P is gripped by the gripper 12, and when the transfer material P is used in the color image forming apparatus, the transfer material P is used.
Since it is firmly supported and superimposed and transferred, there is an advantage that the registration resolution of each color image is good, but there is a problem that the structure of the gripper 12 part becomes complicated and the image is missing at the tip of the transfer material, Further, since the transfer material P must be gripped by the gripper 12 without fail, it is impossible to simultaneously hold and convey a plurality of transfer materials on the peripheral surface of the drum-shaped transfer device 10 at the same time. It had the drawback of slow copying speed.

In U.S. Pat.No. 4,712,906, the surface of the transfer drum is formed of a thin layer of elastomer, and a plurality of suction chambers are provided in the circumferential direction in the vicinity of the surface of the drum. There is disclosed a structure in which a suction hole communicating with the suction chamber is provided, and the transfer material is suction-held and conveyed by sucking the transfer material onto the surface of the transfer drum through the suction hole.

According to such a structure, the transfer material does not need to be gripped by the gripper, and a plurality of suction holes are provided in the circumferential direction of the transfer drum so as to continuously suck a plurality of transfer materials onto the surface of the transfer drum. Although it can be held and conveyed, it has a drawback that the holding position of the transfer material cannot be changed, and the structure of the transfer drum becomes extremely complicated, which leads to an increase in size and cost of the apparatus, which is not preferable. Absent. Furthermore,
When the suction device is operated, the surface layer of the elastomer is deformed toward the inside of the transfer drum, and there is a problem that a transfer failure occurs and a good image cannot be obtained.

Further, in JP-A-55-32079, a transfer drum having a dielectric sheet on its surface is used, and a corona charger for adsorbing a transfer sheet (transfer material) is provided inside the transfer drum. A conductive roller or a charging device having a polarity opposite to that of the transfer sheet adsorbing corona charging device is arranged in opposition to the transfer device, and the transfer sheet is held and conveyed on the dielectric sheet on the transfer drum surface by electrostatic adsorption. Is disclosed.

The transfer drum disclosed in the publication has a feature that a transfer sheet can be very efficiently held and conveyed on the transfer drum without requiring a gripper or a suction device.

Problems to be Solved by the Invention According to the configuration disclosed in the above publication, the transfer sheet and the dielectric sheet are separated from each other after the charge on the surface of the transfer sheet adsorbed to the dielectric sheet is removed by the static eliminator, This is done by inserting a separation claw between the dielectric sheet and the transfer sheet.

However, according to the results of the research experiments by the present inventors,
It is extremely difficult to separate the transfer sheet electrostatically attracted to the dielectric sheet by the static eliminator and the separating claw, and if the separating claw is strongly pressed against the dielectric sheet to ensure the separation, the dielectric sheet It has been found that it is difficult to obtain a transferred image of good quality because of scratching the surface, and the dielectric sheet must be frequently replaced.

The inventors of the present invention have conducted a research experiment to solve the above-mentioned problems. As a result, for example, even if a transfer sheet (transfer material) is electrostatically adsorbed on a transfer material carrier such as a dielectric sheet, the transfer material carrier is It has been found that the transfer material can be very effectively separated from the transfer material carrier by locally deforming it.

The present invention has been made based on such novel findings.

Therefore, an object of the present invention is to separate the recording material carried on the recording material carrier extremely efficiently and without damaging the recording material carrier, and to obtain an image of good quality for a long period of time. A forming device is provided.

Means for Solving the Problems The above object is achieved by the image forming apparatus according to the present invention.
The present invention relates to a recording material carrier that carries and conveys a recording material, an image forming unit that forms an image on the recording material carried on the recording material carrier, and a peeling member that separates the recording material from the recording material carrier. An image forming apparatus having: a separation member including: a separation member that is provided on a side opposite to a side of the recording material carrier that carries a recording material and that deforms the recording material carrier; The recording material carrying member is inserted between the recording material carrying member and the surface of the recording material carrying member opposite to the surface of the recording material carrying the unfixed image and presses the recording material carrying member. An image forming apparatus, comprising: a rotating body for rotating the rotating body, the rotating body being provided in the vicinity of the peeling member when the rotating body presses the recording material carrying body.

Embodiment Next, the image forming apparatus according to the present invention will be described in more detail with reference to the drawings.

FIG. 7 shows an embodiment in which the image forming apparatus according to the present invention is embodied in a color electrophotographic apparatus. In this embodiment,
An image carrier, which is rotatably supported by a shaft and rotates in the direction of the arrow, that is, the electrophotographic photosensitive drum 1, is uniformly charged by the primary charger 2, and is exposed in accordance with image information by exposure means such as a laser beam exposure device. The light image 3 is emitted to form an electrostatic latent image on the photosensitive drum 1. The electrostatic latent image is visualized as a toner image on the photosensitive drum 1 by the movable developing device 4, for example.

The movable developing device 4 includes four developing devices 4M, 4C, 4Y and 4B which separately store four color developing agents of magenta color developing agent, cyan color developing agent, yellow color developing agent and black color developing agent.
And a guide (not shown) which holds these four developing devices and can move in the horizontal direction. The movable developing device 4 conveys a desired developing device to a developing position facing the outer peripheral surface of the photosensitive drum 1, and develops the electrostatic latent image on the photosensitive drum.

The visible image, that is, the toner image, on the photosensitive drum 1 is carried by a transfer device 30 which will be described in detail later, and is conveyed in the direction of the arrow in the drawing by the transfer device 30, and then the photosensitive drum 1 is transferred.
Is transferred to the recording material, that is, the transfer material P that is brought into contact with the recording material P.
The transfer material P is supplied to the transfer device 30 by the registration roller 6a in synchronization with the image.

The photosensitive drum 1 is a cleaning device for cleaning the residual toner on the surface.
After being cleaned at 20, it is submitted to the color imaging process again.

An embodiment of the transfer device 30 used in the color electrophotographic apparatus of this embodiment will be described with reference to FIGS. 1 and 2. In this embodiment, the transfer device 30 has cylindrical rings 31 and 32 provided at both ends and a connecting portion 33 that connects the rings 31 and 32. These cylindrical rings 31, 32 and the connecting portion
Reference numeral 33 constitutes a recording material carrier made of a dielectric film, that is, a drum frame body around which the transfer material carrier sheet 34 is wound.

In this embodiment, the drum frame body around which the transfer material carrying sheet is wound in this way constitutes the transfer drum 30D, and the outer diameter of the transfer drum 30D is set to 160 mm. As shown in (b), the circumference of the transfer drum 30D is A3 size or B
One transfer material P of 4 size in the lengthwise direction, A size or B5
The size of the transfer material P was set to be able to hold two sheets in the lengthwise direction.

In this embodiment, although not particularly shown, the size of the transfer material to be used is detected by the detection means, and the number of sheets to be created is also detected by the detection means, and based on these, one sheet is adsorbed on the transfer drum. It is possible to determine whether or not two sheets are adsorbed.

In this embodiment, the transfer device 30 further includes a separating means 40.
The separating means 40 includes a separating claw support 41 provided along the axial direction of the transfer drum 30D, a plurality of separating members fixed to the supporting body 41, and three separating claws 42 in this embodiment. For the purpose to be described later, a separation outer pressing roller 42a as a rotating body is integrally provided at the tip of the separation claw 42. Also, at both ends of the support 41, there are shown in FIGS.
As can be seen from the figure, abutting rollers 45, 46 are provided via suitable support plates 43, 44. The butting rollers 45, 46
When the separation claw operation clutch (not shown) is actuated, is abutted on the cylindrical rings 31, 32 of the transfer drum 30D and guided by the guide grooves 35, 36 formed in the rings 31, 32,
The tip of the separation claw 42 is rotated downward, that is, in the normal direction of the transfer drum 30D.

The operation of the separation claw 42 will be briefly described with reference to FIGS. 12 (A) and 12 (B). As shown in FIG. 12 (A), the separation claw 42 is always biased to the left by the spring 76 and is in the non-operating position where the normal separation operation is not performed. Here, the support body 41 that supports the separation claw 42 is rotatable about a shaft 77, and the support body 41 is a half-rotation clutch 7 controlled by the CPU 72.
It is operated by a substantially semicircular actuating plate 73 supported by the output shaft 78 of 4. The half-rotation clutch 74 transmits the drive from the drive means 75 such as a belt or a chain to the output shaft 78 when the clutch is engaged. Next, when the separation is performed by the separation claw 42, a signal is output from the CPU 72, and the shaft 78 is rotated half a turn by connecting the half-rotation clutch 74 from the state of FIG. Therefore, the operating plate 73 rotates the support body 41 counterclockwise about the shaft 77 and moves the separating claw 42 to the operating position for separating as shown in FIG. 12 (B). When the separation is completed, the shaft 78 is half-rotated by the half-rotation clutch 74 and the restoring force of the spring 76 causes the support body 41 and the separation claw 42 to rotate clockwise around the shaft 77, as shown in FIG. Return to the inoperative position as shown in.

Although not shown in FIGS. 12 (A) and 12 (B),
42a, 45, 46, the support plates 43, 44 are also the above-mentioned separation claw 42, support 4
Performs the same operation as 1.

A notch 37 is formed in the connecting portion 33 so that the separation claw 42 can be easily inserted between the transfer material carrying sheet 34 and the transfer material P attracted and carried by the transfer material carrying sheet 34. As shown in FIGS. 1 and 5, the front end of the transfer material carrying sheet 34 has a cut 34a along the notch 37 of the connecting portion 33 up to the transfer material non-image area. 34 (fifth
It is fixed to the connecting portion 33 such that the curvature of the shaded portion in the figure) locally increases.

Further, the transfer device 30 will be described. In the present embodiment, the transfer device 30 has a transfer material adsorbing means 50 for adsorbing and holding the transfer material P fed to the transfer device 30 on the transfer material carrying sheet 34. . As shown in FIG. 7, the transfer material attracting means 50 is provided inside the transfer drum 30D and applies a charge having a polarity opposite to that of the toner image on the photosensitive drum 1 to the back surface of the transfer material carrying sheet 34. It has a suction corona charger 51 and a conductive roller 52 provided outside the transfer drum 30D. This conductive roller 52 is grounded, and a corona charger for adsorption is used.
51 becomes a counter electrode, and charges are injected into the transfer material P.
The transfer material carrying sheet 34 serves to electrostatically adsorb the transfer material P.

Preferably, the transfer material P is supplied so that the front end of the transfer material P overlaps the cut 34a of the transfer material carrying sheet 34 and does not enter the image area. For continuous image formation,
If the length of the transfer material to be used in the transport direction is less than half the length of the peripheral length of the transfer drum minus the width of the connecting portion, the second transfer material is continuously fed to the first transfer material. Then, the second transfer material is adsorbed on the transfer material-carrying sheet at a position symmetrical to the first transfer material (FIG. 3B). That is, the transfer material carrying sheet
At the same time, two transfer materials P are adsorbed and conveyed to the 34.

The transfer material P adsorbed by the transfer device 30 is conveyed to the transfer area where the transfer charger 15 is arranged, and the first color developing material, for example, magenta toner on the photosensitive drum 1 is transferred to the first sheet. In order to transfer to the material P, a charge having a polarity opposite to that of the toner is applied to the back surface of the transfer material carrying sheet 34 by using the transfer corona charger 15. Subsequently, the same latent image is formed again, and the toner of the first color is developed on the photosensitive drum, and similarly, the first toner is formed on the second transfer material.
Transfer the toner of the color. By the time the first transfer material reaches the position of the conductive roller 52 for the second time, the conductive roller 52 is released, and the toner image transferred on the transfer material P is not disturbed, for example, from the transfer material carrying sheet 34. Separated by 2 mm or more.

Then, the second color toner image on the photoconductor drum 1 formed in synchronization with the first transfer material onto which the first color toner image has been transferred is transferred by the transfer corona charger 15. The toner image of the second color is also transferred onto the transfer material of the second sheet onto which the toner image of the first color is transferred onto the transfer material P of the first sheet. Similarly, four color toner images are transferred to the two transfer materials P in the same manner.

The transfer device 30 includes a transfer material carrying sheet 34 in order to weaken the attraction force of the transfer material to the transfer material carrying sheet after the transfer process.
A pair of AC corona dischargers 16 are provided to face each other with the transfer material P and the transfer material carrying sheet 34 being discharged.

In order to separate the first transfer material P from the transfer material-carrying sheet 34, as is understood from FIG. 1 and FIG.
The abutting rollers 45 and 46 of 40 are operated by a separating claw operation clutch (not shown), and the cylindrical ring 3 of the transfer drum 30D
It is guided by guide grooves 35, 36 formed in the rings 31, 32, which are in contact with 1, 32. As a result, the tip of the separation claw 42 is rotated downward, that is, in the direction of the normal line of the transfer drum 30D toward the transfer material carrying sheet 34, and the separation outer pressing roller 42a is driven integrally with the separation claw 42. Is the transfer sheet 3
Pressed on 4. Further, the outer separation pressing roller 42a moves along the notch 37 of the connecting portion 33, and the transfer material carrying sheet is formed.
When the curvature of 34 is locally changed, the separation claw 42 is inserted between the tip of the first transfer material and the transfer material carrying sheet 34,
The transfer P is separated from the transfer material carrying sheet 34. At this time, the separation inner pressing roller 53 is not driven.

When the second transfer material P is to be separated from the transfer material carrying sheet 34, the separation inner pressing roller 53 arranged in the transfer drum 30D causes the CPU 72 to separate the transfer material P from the transfer material carrying sheet 34, as will be understood from FIGS. 4 and 6.
When the solenoid 79 controlled by the above is operated, the solenoid 79 is pressed against the transfer material carrying sheet 34 from the inside. As shown in FIG. 4, the solenoid 79 is connected by a connecting member 81 to a support member 83 that supports the inner pressing roller 53 for separation. The connecting member 81 is rotatable around a shaft 80, and is a supporting member.
83 and solenoid 79 are pivotally supported. Also, the support member 83
Is biased downward by a spring 82. Therefore, as described above, when the solenoid 79 is actuated from the state shown in FIG. 4, the connecting member 81 is rotated clockwise about the shaft 80 to support the supporting member.
The roller 53 supported by 83 is pushed up to the state shown in FIG. When the solenoid 79 is turned off, the state shown in FIG. 4 is restored. Further, the outer pressing roller 42a for separation is also guided by the abutting rollers 45, 46 of the separating means 40 in the grooves 35a, 36a provided on the opposite side of the connecting portion 33 of the rings 31, 32, respectively, The transfer material-carrying sheet 34 is pressed against the transfer material-carrying sheet 34 from the outside to locally change the curvature of the transfer material-carrying sheet to separate the curvature of the leading end of the transfer material, thereby transferring the transfer material P and the transfer material-carrying sheet.
The transfer material P is separated by inserting a separation claw 42 between the transfer material P and 34. When the outer pressing roller presses the transfer material carrying sheet, the outer pressing roller is in the vicinity of the separating claw, so that the separating claw can prevent the transfer material carrying sheet from being damaged. As shown in FIG. 6, it is preferable that the separation claw does not come into contact with the transfer material carrying sheet.

When the transfer material P is separated, the transfer material P and the transfer material carrying sheet
In order to prevent image disturbance due to peeling discharge that occurs when 34 is separated, it is preferable to perform AC corona discharge using the corona discharger 54.

When the length of the transfer material in the conveyance direction is longer than the above (FIG. 3 (A)), the front end of the transfer material P is placed at the same position as the front end of the first transfer material described above. The same transfer and separation process as in the case of the first transfer material is performed by adsorbing to 34.
At this time, the inner pressing roller 53 for separation is not driven.

After the transfer and separation steps are completed, the transfer material P is conveyed to the fixing device 18 and heated to mix and fix the toner, and the paper is discharged to complete the image formation.

FIG. 8 shows another embodiment of the transfer device 30.

In the above-described embodiment, as understood from FIG. 2, since the transfer drum frame is formed by the cylindrical rings 31 and 32 and the connecting portion 33 and the transfer material carrying sheet 34 is wound, ,
The transfer material adsorption position with respect to the transfer material carrying sheet 34 is determined. According to the present embodiment, the transfer drum D has a cylindrical ring 31, 32 fixed to a central support shaft 62 via an appropriate support member 61 to form a transfer drum frame, and a seamless drum is formed on the surface of the frame. It is configured by winding the transfer material carrying sheet 34.

Therefore, according to the present embodiment, since the cylindrical seamless transfer material carrying sheet 34 is used, the transfer material suction position is not specified and is free. The transfer material P can be freely fed without the need to strictly control the timing relationship with the transfer drum.
The adsorption corona charger 51 and the conductive roller 52 adsorb onto the transfer material carrying sheet 34.

When such a transfer device 30 is used, as shown in FIG. 7, a transfer material detection sensor 63 is provided downstream of the suction means 50 to detect the transfer material position. The transfer material detection sensor 63 is arranged upstream from the circumferential transfer position of the transfer drum 30 by a length L or more, where L is the length from the exposure position on the circumference of the photosensitive drum 1 to the transfer position. When the length of the transfer material in the conveying direction is less than half the peripheral length of the transfer drum in continuous copying, the second transfer material is continuously fed to the first transfer material. After detection by the transfer material detection sensor 63, a latent image is formed on the photosensitive drum in synchronism with the development, and then development and transfer are performed.

In this embodiment, after the four color toners have been transferred, the first and second transfer materials P are both driven by a separation inner pressing roller 53 and a separation claw as shown in FIG. The outer pressing roller 42a for separation, which is driven integrally with 42, is the transfer material carrying sheet 3
It is pressed against 4, locally changing the curvature of the transfer material-carrying sheet 34, separating the tip of the transfer material by the curvature, and separating by inserting a separation claw 42 between the transfer material and the kanji material-carrying sheet.

FIG. 9 shows the separating means used in the transfer device according to the present invention.
Another embodiment of 40 'is shown. The separating means 40 'has the same structure as the separating means described with reference to FIG. 1, but differs in the arrangement of the separating member, that is, the separating claw 42, as shown in the drawing. That is, according to the present embodiment, the separation claws 42 at the center are formed so as to project most toward the transfer drum D, and the separation claws 42 on both sides thereof are configured to become shorter toward both ends. Further separating claw in the center
An outer separation pressing roller 42a is integrally provided only with 42.

According to the component separating means 40 ', when the transfer material P is separated, first, the outer pressing roller 42a for separation of the central separation claw 42 is separated.
And the inner pressing roller 53 for separation are applied to the transfer material carrying sheet to locally change the curvature of the transfer material carrying sheet 34, and the tip of the transfer material P is transferred to the transfer material carrying sheet 34. Separate from. Then, the transfer material P
First, the separation claw 42 closest to the transfer material in the central portion is inserted between the transfer material carrying sheet 34 and the transfer material carrying sheet 34, and as the transfer material P advances,
The transfer material P is gradually lifted to a large extent, the separation area expands, and the separation claws 42 located on both sides of the separation claw in the central portion are also inserted between the transfer material P and the transfer material carrying sheet 34. Further spreads, and the separation of the transfer material and the transfer material carrying sheet 34 is completed.

In this embodiment, since the transfer material sheet 34 is deformed at one place, it is easy to locally deform the transfer material carrying sheet.

In FIG. 10, in the transfer device 30, instead of the transfer material carrying sheet 34 made of the dielectric film described in the above embodiment, the transfer material carrying surface is an insulating layer 34a and the opposite surface is a conductive layer 3a.
The transfer material carrying sheet 34, which is designated as 4b, is used. Further, the conductive layer 34b of the transfer material carrying sheet 34 is insulated from the cylindrical rings 31, 32, etc., which form the transfer drum frame, and the conductive layer 34b
Although not shown, 34b is configured to be able to apply a DC bias voltage of a predetermined value.

When the transfer material P is conveyed to the transfer drum 30D, a bias voltage having a polarity opposite to that of the toner image on the photosensitive drum 1 is applied to the conductive layer 34b, and at the same time, the attracting corona charger 72 is operated to cause the toner on the photosensitive drum. Weakly discharge to the same polarity as the image. For example, when the toner polarity is negative, the transfer corona discharge current value of −50 μA and the bias voltage of +1.5 KV are applied, so that the transfer material P is appropriately adsorbed and conveyed to the transfer material carrying sheet 34 and the photosensitive drum 1 is used. The upper toner image can be transferred onto the transfer material P. In the full-color mode, the toner images of the second and subsequent colors are subjected to good multiple transfer by sequentially increasing the bias voltage by 500 V, for example.

In this embodiment, the separating means 40 is simply the separating claw 42 and the separating claw 42.
And a transfer separation electrode 70 provided at a position opposed to the electrode 70. The electrode 70 is connected to a DC power supply 71.

At the time of separating the transfer material, when the front end of the transfer material P is conveyed to the vicinity of the separation claw 42, for example, the transfer material carrying sheet 34 is attached to the electrode 70 arranged at a position about 7 mm away from the transfer material carrying sheet 34.
A voltage having a polarity opposite to that of the voltage applied to the conductive layer 34b is applied, for example, a voltage having a potential difference with the transfer material carrying sheet of about 4 KV. The portion of the transfer material carrying sheet 34 facing the electrode 70 is pulled toward the electrode 70 by an electric force, and the transfer material carrying sheet 34 is locally deformed so as to have an increased polar ratio. Therefore, in the deformed portion, the transfer material is separated from the transfer material carrying sheet, and the separation claw is guided between the separated transfer material and the transfer material carrying sheet to transfer the transfer material P.
Separation is completed. The transfer material is conveyed to the fixing device 18, and is subjected to color mixture fixing, and then discharged.

Although the above embodiments have been described with reference to a color electrophotographic apparatus, the present invention can be applied to other image forming apparatuses equipped with a transfer device, and the transfer device is limited to a cylindrical shape. is not.

As described above, the image forming apparatus according to the present invention is configured to separate the recording material from the recording material carrier by locally deforming the recording material carrier. Only by providing the separating means having a simple structure, the recording material held on the recording material carrier can be separated very efficiently and without damaging the recording material carrier, and an image of good quality can be obtained. It has the feature that it can.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a transfer device used in an image forming apparatus according to the present invention. FIG. 2 is a perspective view showing a transfer drum frame of the transfer device shown in FIG. FIGS. 3A and 3B are explanatory views showing the form of the transfer material wound around the transfer drum. FIG. 4 is a side view for explaining the separating means used in the transfer device of FIG. FIG. 5 is a perspective view for explaining the relationship between the connecting portion of the transfer device of FIG. 1 and the transfer material carrying sheet. FIG. 6 is an explanatory view for explaining the separating operation by the separating means. FIG. 7 is a schematic structural sectional view of an embodiment of the image forming apparatus according to the present invention. FIG. 8 is a perspective view showing another embodiment of the transfer device constructed according to the present invention. FIG. 9 is a plan view showing another embodiment of the separating means used in the transfer device constructed according to the present invention. FIG. 10 is a schematic sectional view of a color electrophotographic copying machine which is another embodiment of the image forming apparatus. FIG. 11 is a perspective view showing an example of a conventional transfer device. 12 (A) and 12 (B) are side views of the separating means for explaining the operation of the separating claw. 1: Image carrier 30: Transfer device 30D: Transfer drum 31, 32: Cylindrical ring 33: Connection part 34: Recording material carrier 34a: Insulating layer 34b: Conductive layer 40, 40 ': Separation means 42: Separation claw 42a : Separation outer pressing roller 50: Transfer material adsorption means 51, 72: Adsorption corona charger 52: Conductive roller 53: Separation inner pressing roller 63: Transfer material detection sensor 70: Transfer material separation electrode

Claims (11)

[Claims] 1. A recording material carrier for carrying and conveying a recording material, image forming means for forming an image on the recording material carried on the recording material carrier, and separation for separating the recording material from the recording material carrier. In the image forming apparatus having a separating unit including a member, the separating unit is provided on a side opposite to a side of the recording material carrying body which carries the recording material, and a deforming member which deforms the recording material carrying body, The recording material carrying member is inserted between the recording material carrying member and the surface of the recording material carrying member opposite to the surface having the unfixed image of the recording material and presses the recording material carrying member. An image forming apparatus, wherein the rotating body is provided in the vicinity of the peeling member when the rotating body presses the recording material carrying body. 2. The image forming apparatus according to claim 1, wherein the rotating body is provided integrally with the peeling member. 3. The apparatus according to claim 1 or 2, wherein the apparatus has a suction means for sucking the recording material on the recording material carrier before forming an image on the recording material. Image forming apparatus. 4. The image forming apparatus according to claim 3, wherein the suction means electrostatically attracts the recording material to the recording material carrier. 5. The image forming apparatus according to claim 1, wherein the recording material carrier has a drum shape. 6. The deformation member and the rotating body do not deform the recording material carrier when the recording material is not separated from the recording material carrier.
The image forming apparatus according to any one of items 1 to 5. 7. The peeling member does not come into contact with the recording material carrier when the rotating body presses the recording material carrier, according to any one of claims 1 to 6. The image forming apparatus according to item. 8. The peeling member is inserted into a portion of the rotating body that deforms the recording material carrier when the rotating body presses the recording material carrier. The image forming apparatus according to any one of items 1 to 7. 9. The image forming means includes an image carrier for carrying an image, and a transfer means for transferring the image of the image carrier onto a recording material carried by the recording material carrier. The image forming apparatus according to any one of claims 1 to 8, wherein a plurality of images are superimposed and transferred onto the recording material carried by the recording material carrier. 10. The apparatus according to claim 1, wherein the apparatus is capable of forming a full-color image on a recording material.
The image forming apparatus according to any one of Item 9. 11. The image forming apparatus according to any one of claims 1 to 10, wherein the deformable member is a rotating body that can contact the recording material carrier.