JPH04280266A - Image formation device with transfer drum - Google Patents

Abstract

PURPOSE:To prevent the deterioration of cleaning characteristics even upon occurrence of damage to the side edge of a photo-sensitive drum by providing an image formation area on the peripheral surface of the drum at the inner side of a position corresponding to both side edges of a transfer sheet material. CONSTITUTION:A cleaning blade 68 as a cleaning means 6 is continuously extended along an image formation area 70 on the peripheral surface of a photo-sensitive drum body 14, but not extended up to both side edges of a transfer sheet material 62 on a transfer drum 4. Both edges of the aforesaid cleaning blade 68 are positioned slightly outside both edges of the image formation area 70, and slightly inside the inner edges of the support sections 36 and 46 of flange members 32 and 34 for the transfer drum 4. In this case, a seal piece 72 is pasted to the front of a housing 64 at both axial outsides of the cleaning blade 68, and in contact with the peripheral surface of a photo-sensitive drum at the outside of the image formation area 70. According to this construction, the photo-sensitive drum can be precisely interlocked with the transfer drum 4 for rotation.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an image forming machine having a transfer drum together with a photosensitive drum, and more specifically, a toner image is formed on a photosensitive member disposed on the circumferential surface of the photosensitive drum. The present invention relates to an image forming apparatus in which a toner image is transferred onto an image forming sheet member removably mounted on the circumferential surface of a transfer drum.

0002

BACKGROUND OF THE INVENTION As is well known, in an image generating machine such as a multicolor copying machine or a multicolor laser beam printing machine, a photosensitive drum is rotatably disposed and a transfer drum is rotatably disposed. ing. A photoreceptor is disposed on the circumferential surface of the photoreceptor drum, and a toner image is formed on the photoreceptor by a well-known method while the photoreceptor drum is rotated in a predetermined direction. The transfer drum includes a pair of flange members disposed on both side edges and a transfer sheet member, and the transfer sheet member, which is advantageously formed from a flexible synthetic resin sheet, has a pair of side edges disposed on each side of the transfer sheet member. Cover the peripheral surface of the flange member. Such a transfer drum is rotatably mounted and is also movably mounted between an active position and a non-active position. An image forming sheet member, which may be an ordinary sheet of paper, is removably mounted on the transfer sheet member of the transfer drum. The toner image formed on the photoreceptor is transferred onto an image forming sheet member mounted on a transfer drum. At this time, the transfer drum is positioned at the operating position, and the surface of the image forming sheet member is brought into close contact with the circumferential surface of the photosensitive drum. Then, the photosensitive drum and the transfer drum are rotated synchronously. An output gear is disposed on one edge of the photosensitive drum, and an input gear that engages with the output gear is disposed on one edge of the transfer drum. and is transmitted to the transfer drum via the input gear. In relation to the photosensitive drum,
A cleaning means is also provided for removing toner remaining on the circumferential surface of the photosensitive drum after transfer. The cleaning means includes a cleaning blade made of synthetic rubber, and the tip of the cleaning blade is brought into contact with the circumferential surface of the photosensitive drum. When producing a multicolor image on an image producing sheet member, toner images are formed and transferred for each of a plurality of colors.

[0003] In the above-mentioned image generation machine, it is important that the toner images of a plurality of colors are transferred to the desired portions of the image generation sheet member without being shifted from each other. In this case, it is important that the transfer drum is rotated in sufficiently precise synchronization with the rotation of the photosensitive drum. A so-called backlash inevitably exists in the engagement of the gears, and therefore, the synchronous rotation of the photosensitive drum and the transfer drum cannot be dependent only on the engagement of the output gear and the input gear. Therefore, in conventional image generating machines, when the transfer drum is positioned at the operating position, both side edges of the circumferential surface of the transfer drum (at the both side edges, the transfer sheet covers the circumferential surface of the flange member) are It is brought into contact with both side edges of the photosensitive drum, thus uniquely defining the relative position of the photosensitive drum and the transfer drum, and therefore the relative position of the output gear and the input gear as required, and controlling the rotation of the photosensitive drum. to synchronize the rotation of the transfer drum with sufficient precision as desired (the central area of the circumferential surface of the transfer drum is sufficiently flexible to accommodate variations in the thickness of the imaging sheet member mounted thereon); Therefore, the relationship between the photosensitive drum and the transfer drum is made sufficiently precise by bringing the central area of the peripheral surface of the transfer drum into contact with the central area of the peripheral surface of the photosensitive drum via the image forming sheet member attached thereto. ).

0004

SUMMARY OF THE INVENTION In the conventional image generator, there are the following problems to be solved. If both side edges of the circumferential surface of the transfer drum are brought into contact with both side edges of the circumferential surface of the photosensitive drum, the photosensitive member will inevitably be damaged on both sides of the circumferential surface of the photosensitive drum during repeated use. Generally, both side edges of the circumferential surface of the photosensitive drum are not used for the generation of toner images, so even if both side edges of the circumferential surface of the photosensitive drum are damaged, there will be no direct negative effect on the generation of toner images. . However, if both sides of the circumferential surface of the photosensitive drum are damaged, toner that is scattered during development or the like tends to stay in the damaged area. When such toner accumulation occurs, the cleaning blade that comes into contact with the circumferential surface of the photosensitive drum at both side edges receives local excessive force at the toner accumulation area, and as a result, the cleaning blade on both sides Distortion is generated not only at the edges but also at the center, which significantly reduces the cleaning properties and thus creates an adverse effect on toner image formation.

In order to prevent damage to both side edges of the circumferential surface of the photosensitive drum, buffer pieces made of a flexible material such as synthetic rubber or felt are attached to both side edges of the circumferential surface of the transfer drum. It has also been proposed and put to practical use to bring the peripheral surface of the transfer drum into contact with the peripheral surface of the photosensitive drum via a buffer piece. However, when such a buffer piece is used, due to errors in hardness or thickness of the buffer piece, when the circumferential surface of the transfer drum and the circumferential surface of the photosensitive drum are brought into contact with each other via the buffer piece, the transfer between the photosensitive drum and the transfer may occur. A considerable error occurs in the relative position with respect to the drum, and therefore an error occurs in the synchronous rotation of the photosensitive drum and the transfer drum.

The present invention has been made in view of the above-mentioned facts, and its main technical problem to be solved is that in the above-described image forming machine, even if both side edges of the circumferential surface of the photosensitive drum are damaged, cleaning is not possible. The object of the present invention is to improve the toner image so that the properties thereof are not deteriorated and, therefore, formation and transfer of good toner images can be stably performed over a long period of time.

[0007]

[Means for Solving the Problems] In order to achieve the above technical problem, in the present invention, both side edges of the circumferential surface of the transfer drum, that is, both side edges of the transfer sheet member, are connected to the circumferential surface of the photosensitive drum. The photosensitive drum is brought into direct contact with both side edges without using a buffer piece, and the image forming area on the circumferential surface of the photosensitive drum is defined inside the both side edges on which both side edges of the circumferential surface of the transfer drum are abutted. In addition, the cleaning blade in the cleaning means is extended continuously over the image forming area on the circumferential surface of the photosensitive drum and is brought into contact with the photosensitive drum. Configure it so that it does not come out.

That is, according to the present invention, there is provided a rotatably mounted photosensitive drum, an operating position where the photosensitive drum is rotatably mounted and a part of the circumferential surface is in contact with the circumferential surface of the photosensitive drum, and a circumferential surface of the photosensitive drum. The transfer drum is equipped with a transfer drum movably mounted between a non-working position separated from the surface, and a cleaning means, a photoreceptor is disposed on the circumferential surface of the photoreceptor drum, and the transfer drum is The cleaning means includes a pair of flange members disposed on both side edges and a transfer sheet member whose side edges cover the peripheral surfaces of the pair of flange members, and the cleaning means extends in the axial direction of the photosensitive drum. and includes a cleaning blade whose tip is brought into contact with the circumferential surface of the photosensitive drum, a rotary output means is fixed to one edge of the photosensitive drum, and a rotary output means is fixed to one edge of the transfer drum. The rotation input means to be engaged is fixed, the rotation of the photosensitive drum is transmitted to the transfer drum via the rotation output means and the rotation input means, and the image forming area on the circumferential surface of the rotary drum is An image forming sheet member is removably attached to a transfer area defined inside the flange member on the circumferential surface of the transfer drum where a toner image is formed, and the toner image formed on the circumferential surface of the photosensitive drum is The image is transferred onto an image forming sheet member mounted on the circumferential surface of the transfer drum, and the toner remaining on the circumferential surface of the photosensitive drum after the transfer is removed from the circumferential surface of the photosensitive drum by the cleaning means. In this type of image generating machine, when the transfer drum is positioned at the operating position, the both side edge portions of the transfer sheet member of the transfer drum that cover the circumferential surfaces of the pair of flange members touch the photosensitive drum. The cleaning means is brought into direct contact with both side edges of the peripheral surface of the photosensitive drum, and the image forming area on the peripheral surface of the photosensitive drum is defined inside the both side edges with which the transfer sheet is brought into contact. The cleaning blade extends continuously over the image forming area on the circumferential surface of the photosensitive drum and is brought into contact with the image forming area, and the cleaning blade extends on both side edges with which the transfer sheet member comes into contact. An image generator is provided, characterized in that:

Preferably, the cleaning means also includes a pair of seal pieces that abut against both side edges of the circumferential surface of the photosensitive drum. The sealing piece can be formed from a pile sheet piece.

0010

[Function] In the image forming apparatus of the present invention, even if both side edges of the circumferential surface of the photosensitive drum are damaged and toner remains in the damaged area, the cleaning blade does not extend to both side edges of the circumferential surface of the photosensitive drum. Since the cleaning blade is not allowed to come out, the cleaning blade does not act on toner that has accumulated in the damaged area, so that no undesirable strain is created in the cleaning blade and the cleaning characteristics are not degraded.

[0011] The toner remaining in the damaged areas on both side edges of the circumferential surface of the photosensitive drum is removed by the action of a pair of seal members that are constructed separately from the cleaning blade and are brought into contact with both side edges of the circumferential surface of the photosensitive drum. This prevents it from being partially removed and scattering around.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an image generator constructed according to the present invention will be described in more detail below with reference to the accompanying drawings.

Referring to FIGS. 1, 2, and 3, the illustrated multicolor image generator includes a photosensitive drum 2, a transfer drum 4,
and cleaning means 6. Photosensitive drum 2
includes a stationary support shaft 8 fixed in position. A pair of flange members 10 and 12 are rotatably mounted on the substantially horizontally extending support shaft 8 at an interval in the axial direction. A photosensitive drum main body 14 is mounted. A suitable photoreceptor is disposed on the circumferential surface of the photoreceptor drum main body 14. A cylindrical protrusion 15 that protrudes outward in the axial direction is formed on the flange member 12, and a gear member 16 is fixed to this protrusion 15. The gear member 16 has a gear 18 constituting rotation input means and a gear 20 constituting rotation output means. The gear 18 is drivingly connected to a rotary drive source (not shown), which may be an electric motor, via a suitable transmission gear train (not shown).
The flange members 10 and 12 and the photosensitive drum body 14 are rotated in the direction shown by the arrow 22 in FIGS. 1 and 3 by the rotational drive source.

The transfer drum 4 also includes a support shaft 24,
This support shaft 24 extends substantially parallel to the support shaft 8 of the photosensitive drum 2 . 2 and 3, the illustrated imager includes a pair of axially spaced support members 26 and 28.
are arranged, and the support shaft 24 is fixed to these support members 26 and 28. Support members 26 and 28 are pivotably mounted about a pivot axis 30 extending substantially parallel to support shaft 24 and are pivoted by a suitable pivot mechanism (not shown), which may comprise an electromagnetic solenoid. , the working position shown in solid lines in Figs. 2 and 3 and Fig. 3
and a non-operating position shown by a two-dot chain line. A pair of flange members 32 and 34 are rotatably mounted on the support shaft 24 via bearing means (not shown). Mainly referring to FIG. 1, the flange member 32 has a substantially cylindrical shape, and includes a cylindrical support portion 36 and an annular groove portion 3 located sequentially from the outside in the axial direction toward the inside.
8 and a cylindrical connecting portion 40. The circumferential surface of the support portion 36 has a predetermined outer diameter D1, the circumferential surface of the groove portion 38 has an outer diameter D2 that is slightly smaller than the above-mentioned D1, and the connecting portion 40 has a predetermined outer diameter D2 that is slightly larger than the above-mentioned outer diameter D2. It has an outer diameter D3 that is somewhat smaller than the outer diameter D1. A notch 42 is formed at a specific angle portion of the connecting portion 40 . The other flange member 34 also has a substantially cylindrical shape, and includes a cylindrical protrusion 44 (FIG. 2), a cylindrical support 46, and
It has an annular groove portion 48 and a cylindrical connecting portion 50. Support part 4
6, the outer diameter D2 of the groove, and the outer diameter D of the connecting part 50.
3 is the same as the outer diameter D1 of the support part 36, the outer diameter D2 of the groove part 38, and the outer diameter D3 of the connecting part 40 of the flange member 32. The outer diameter D4 of the protrusion 44 is somewhat smaller than the outer diameter D2 of the groove 48. The above-mentioned notch 4 is provided at a specific angle portion of the connecting portion 50.
A notch 52 corresponding to No. 2 is formed. A gear 54 is fixed to the protrusion 44 . The gear 54 constituting the rotation input means is engaged with the gear 20 on the photosensitive drum 2, and the rotation of the photosensitive drum 2 is transmitted to the transfer drum 4 via the gears 20 and 54 (more on this later). . A stay member 56 is fixed between the pair of flange members 32 and 34. One end of the stay member 56 extending in the axial direction connects to the connecting portion 40 of the flange member 32.
The stay member 56 is positioned in the notch 42 formed in the connecting portion 40 and fixed to the connecting portion 40 by appropriate connecting means (not shown), and the other end portion of the stay member 56 is formed in the connecting portion 50 of the flange member 34. It is located in the notch 52 in the drawing and is fixed to the connecting portion 50 by suitable connecting means (not shown). The stay member 56 has an upstream portion 58 located on the upstream side when viewed in the rotational direction indicated by the arrow 22, and a downstream portion 59 that extends downstream while being inclined at a slight angle with respect to the upstream portion 58. The surface of the stay member 56 is somewhat recessed than the peripheral surfaces of the support portions 36 and 46 of the flange members 32 and 34. At the upstream portion 58 of the stay member 56, four clamping pieces 60 are arranged at intervals in the axial direction. Each of the clamping pieces 60 is rotatably mounted between a clamping position shown by a solid line in FIG. 1 and a release position shown by a two-dot chain line in FIG. It can be selectively positioned between the clamped position and the released position by suitable actuating means (not shown) including a mechanism (more on this below). The transfer drum 4 is further provided with a transfer sheet member 62 . This transfer sheet member 62 has one end affixed to the upstream portion 58 of the stay member 56, more specifically, a portion of the upstream portion 58 upstream of the clamping piece 60, and is rotated from the one end in the rotational direction shown by the arrow 22. It is wound in the opposite direction, and the other end is attached to the downstream part 59 of the stay member 56. Both side edges of the transfer sheet member 62 closely cover the peripheral surfaces of the support portions 36 and 46 of the flange members 32 and 34, respectively. The transfer sheet member 62 is conveniently made of a flexible synthetic resin sheet such as a polyethylene terephthalate sheet having a thickness of about 100 μm.

As will be understood by referring to FIG. 3 in conjunction with FIG.
Supports 36 and 4 in flange members 32 and 34 of
6 is transferred to the photosensitive drum 2 via the transfer sheet member 62.
The photosensitive drum body 14 is brought into contact with the circumferential surface of the photosensitive drum body 14 . In other words, both side edge portions of the transfer sheet member 62 that cover the support portions 36 and 46 of the flange members 32 and 34 are brought into contact with the circumferential surface of the photosensitive drum body 14 . The outer diameters D2 and D3 of the grooves 38 and 48 of the flange members 32 and 34 and the connecting parts 40 and 50 are the same as those of the supporting parts 32 and 4.
2, and the surface of the stay member 56 is also somewhat recessed than the circumferential surfaces of the support parts 36 and 46 of the flange members 32 and 34, so that the above-mentioned both sides of the transfer sheet member 62 A slight gap exists between the transfer sheet member 62 and the circumferential surface of the photosensitive drum body 14 in areas other than the edge. The outer diameter of the transfer sheet member 62 on both sides of the transfer drum 4 is equal to that of the gear 5.
The outer diameter of the circumferential surface of the photosensitive drum body 14 is set to be the same as the pitch circle diameter of the gear 20. Therefore, when the transfer drum 4 is positioned at the operating position, the gear 20 of the photosensitive drum 2 and the gear 54 of the transfer drum 4 are engaged (in contact with each other in the pitch circle) as required, and the rotation of the photosensitive drum 2 is prevented. It is transmitted to the transfer drum 4 with sufficient precision as required. When the support members 26 and 28 of the transfer drum 4 are positioned in the non-operating position shown by the two-dot chain line in FIG. 3, the entire transfer sheet member 62 is separated from the photosensitive drum body 14. On the other hand, as shown in FIG. 3, the gear 20 and the gear 54 continue to be engaged with each other with so-called play, without coming apart, so that the rotation of the photosensitive drum 2 continues to be transmitted to the transfer drum 4.

The cleaning means 6 will be described with reference to FIGS. 1, 2, and 3. The illustrated cleaning means 6 includes a housing 64 whose entire surface facing the photosensitive drum 2 is open. A support member 66 extending in the axial direction of the photosensitive drum 2 is disposed inside the housing 64, and a cleaning blade 6 is attached to the support member 66.
8 is installed. A cleaning blade 68 that can be formed from any suitable synthetic rubber such as urethane rubber.
has a plate shape that extends in the axial direction of the photosensitive drum 2, and its tip is brought into contact with the circumferential surface of the photosensitive drum body 14.

Continuing the explanation with reference to FIGS. 1 and 2,
In the image generating machine configured according to the present invention, the area of the circumferential surface of the photosensitive drum body 14 of the photosensitive drum 2 used for image formation, that is, the image forming area 70 is Both side edges (i.e., supports 36 and 46 of flange members 26 and 28)
It is important to define this on the axially inner side of the covering part). In the illustrated embodiment, both side edges of the image forming area 70 on the circumferential surface of the photosensitive drum body 14 are connected to the support portions 36 and 44 of the flange members 32 and 34 on the transfer drum 4.
It is located slightly inside the inner edge of the Further, in the image forming machine constructed according to the present invention, the cleaning blade 68 in the cleaning means 6 extends continuously over the image forming area 70 on the circumferential surface of the photosensitive drum body 14, drum 4
It is important that the transfer sheet member 62 does not extend to the above-mentioned both side edges. In the illustrated embodiment,
Both edges of the cleaning blade 68 are connected to the image forming area 7.
0 and slightly inside the inner edges of the support portions 36 and 46 of the flange members 32 and 34 on the transfer drum 4. In the illustrated cleaning means 6, the cleaning blade 68
Seal pieces 72 are attached to the front surface of the housing 64 on both axially outer sides thereof. Such a seal piece 72
are brought into contact with the circumferential surface of the photosensitive drum body 14 at both outer sides of the image forming area 70 . Seal piece 72 may conveniently be formed from a piece of pile sheet, such as a piece of acrylic pile sheet. If desired, the seal piece 72 can be formed from sponge. Furthermore, instead of disposing the seal pieces 72 on both outer sides of the cleaning blade 68, an additional blade may be disposed that is integrally connected to the cleaning blade through a notch. In this case, it is important that the notch reliably prevents the distortion generated in the additional blade from being transmitted to the cleaning blade, thereby causing distortion in the cleaning blade as well. If desired, additional blades can be formed separately from cleaning.

In the illustrated image forming machine, while the photosensitive drum 2 is being rotated in the direction of the arrow 22, a suitable electrostatic latent image forming means (not shown) is installed in the image forming area indicated by the number 74 in FIG. An electrostatic latent image is formed in the image forming area 70 on the circumferential surface of the photosensitive drum body 14, and this electrostatic latent image is developed into a toner image of a desired color by an appropriate developing means (not shown). . On the other hand, in the transfer drum 4, in the nipping area indicated by number 76 in FIG.
The front edge of an image-generating sheet member, which may be a regular paper, fed by a suitable feeding means (not shown) is clamped by a clamping piece 60 disposed on the stay member 56 . That is, the front edge of the image generating sheet member is inserted between the upstream end of the stay member 56 itself and the clamping piece 60 in the release position shown by the two-dot chain line in FIG. It is pivoted to the clamping position, thus clamping the leading edge of the imaging sheet member. Such an image-forming sheet member is wound onto the transfer sheet member 62 in the region inside the above-mentioned both side edges of the transfer sheet member 62 (i.e., the portions covering the support portions 36 and 46 of the flange members 32 and 34. 3, the toner image formed on the circumferential surface of the photosensitive drum body 14 is transferred onto the image forming sheet member mounted on the transfer drum 4. During such transfer, , the transfer drum 4 is positioned at the operating position shown by the solid line in FIG. 4 is rotated. When producing a multicolor image on an image forming sheet member, toner image formation and transfer as described above are repeatedly performed for a plurality of colors. After toner image transfer of a specific color is completed, The transfer drum 4 is placed in the non-operating position shown by the two-dot chain line in FIG. 3 during the period from 1 to 3 until the next color toner image transfer is started.A desired image is generated on the image forming sheet member. and number 80 in Figure 3.
In the release region indicated by , the clamping piece 60 is rotated to the release position, the image-forming sheet member is separated from the transfer drum 4, and the image-forming sheet member is conveyed through a toner image fixing means (not shown). On the other hand, in the cleaning area indicated by the number 82 in FIG. 3, the cleaning blade 68 acting on the image forming area 70 on the circumferential surface of the photosensitive drum body 14 causes residual toner images to remain on the circumferential surface of the photosensitive drum body 14 after the toner image has been transferred. toner is removed.

During transfer, the above-mentioned both side edge portions of the transfer sheet member 62 on the transfer drum 4, that is, the portions that cover the support portions 36 and 46 of the flange members 32 and 34, are exposed to the periphery of the photosensitive drum body 14. It is brought into contact with both side edges of the surface. Therefore, when transfer is repeatedly performed, damage occurs on both side edges of the circumferential surface of the photosensitive drum body 14. However, both side edges of the circumferential surface of the photosensitive drum main body 14 are not used for image formation, and the toner image formed in the image forming area 70 of the photosensitive drum main body 14 is not directly adversely affected by the damage. On the other hand, if damage is generated on both side edges of the circumferential surface of the photosensitive drum body 14,
Toner scattered during development of an electrostatic latent image tends to stay in the damaged area. In conventional image generating machines, the cleaning blade directly acts on both side edges of the circumferential surface of the photosensitive drum body, so toner that stays in the damaged area creates localized excessive stress on the cleaning blade. As a result, distortion is generated not only at both side edges but also at the center of the cleaning blade, and cleaning characteristics tend to be degraded even in the image forming area on the circumferential surface of the photosensitive drum body. However, in the image generator configured according to the present invention,
The cleaning blade 68 does not extend to both side edges of the photosensitive drum body 14 where damage occurs, so that no undesirable distortion is generated in the cleaning blade 68 due to toner staying in the damaged area. , the cleaning properties continue to be maintained in good condition without deterioration. Seal pieces 72 provided separately from the cleaning blade 68 act on both side edges of the circumferential surface of the photosensitive drum 14, thereby partially removing the toner that has accumulated in the damaged area. Further scattering to the surroundings is prevented from there.

Although one embodiment of the image generator constructed according to the present invention has been described above in detail with reference to the accompanying drawings, the present invention is not limited to such embodiment, and the scope of the present invention is not limited to this embodiment. It goes without saying that various modifications and modifications can be made without departing from the invention.

[0021]

Effects of the Invention In the image forming machine improved according to the present invention, both side edges of the transfer sheet member in the transfer drum, that is, the portions that cover the circumferential surfaces of the support portions of the pair of flange members are covered with the circumferential surface of the photosensitive drum body. By bringing the photosensitive drum and the transfer drum into contact with both side edges, that is, the portions located outside the image forming area, sufficiently precise synchronized rotation of the photosensitive drum and the transfer drum is ensured. Even if damage occurs to both side edges of the circumferential surface of the photosensitive drum body due to the contact of both side edges of the transfer sheet on the transfer drum, this will not adversely affect image generation. . Toner tends to accumulate in damaged areas on both side edges of the circumferential surface of the photosensitive drum body, but such accumulated toner is partially removed by the seal piece and is prevented from scattering to the surrounding area. Ru.

[Brief explanation of the drawing]

FIG. 1 is a partial bevel showing the main components of an improved image generator according to the present invention.

FIG. 2 is a partial side view showing main components of the image generator shown in FIG. 1;

FIG. 3 is a partial cross-sectional view showing main components of the image generator shown in FIG. 1; 2: Photosensitive drum 4: Transfer drum 6: Cleaning means 14: Photosensitive drum main body 18: Gear 20: Gear (rotation output means) 32: Flange member of transfer drum 34: Flange member of transfer drum 36: Support part 46 of flange member : Support part 54 of flange member: Gear (rotation input means) 56: Stay member 60: Holding piece 62: Transfer sheet member 68: Cleaning blade 70: Image forming area 7 on the circumferential surface of the photosensitive drum body
2: Seal piece 74: Image forming area 76: Nipping area 78: Transfer area 80: Release area 82: Cleaning area

Claims (5)

[Claims] [Claim 1] A photosensitive drum rotatably mounted;
a transfer drum mounted so as to be rotatable and movable between an active position where a portion of its circumferential surface is in contact with the circumferential surface of the photosensitive drum and a non-active position where it is separated from the circumferential surface of the photosensitive drum; , a cleaning means, a photoreceptor is disposed on the circumferential surface of the photosensitive drum, and the transfer drum has a pair of flange members disposed on both side edges and a pair of flanges on both side edges. a transfer sheet member that covers the circumferential surface of the member, and the cleaning means includes a cleaning blade that extends in the axial direction of the photosensitive drum and whose tip is brought into contact with the circumferential surface of the photosensitive drum. A rotation output means is fixed to one edge of the photosensitive drum, and a rotation input means to be engaged with the rotation output means is fixed to one edge of the transfer drum, so that the rotation of the photosensitive drum is controlled by the rotation. The toner image is transmitted to the transfer drum via the output means and the rotation input means, and a toner image is formed in an image forming area on the circumferential surface of the rotary drum, and a toner image is defined inside the flange member on the circumferential surface of the transfer drum. An image forming sheet member is removably mounted on the transferred transfer area, and the toner image formed on the circumferential surface of the photosensitive drum is transferred onto the image forming sheet member mounted on the circumferential surface of the transfer drum. , in an image generating machine in which toner remaining on the circumferential surface of the photosensitive drum after transfer is removed from the circumferential surface of the photosensitive drum by the cleaning means, when the transfer drum is positioned at the operating position,
The both side edges of the transfer sheet member of the transfer drum that cover the circumferential surfaces of the pair of flange members are brought into direct contact with the both side edges of the circumferential surface of the photosensitive drum, and the The image forming area is defined inside the both side edges with which the transfer sheet is brought into contact, and the cleaning blade in the cleaning means continuously extends over the image forming area on the circumferential surface of the photosensitive drum. 1. An image generating apparatus characterized in that the image generating apparatus extends and is brought into contact with the transfer sheet member, but does not extend to the both side edges with which the transfer sheet member is brought into contact. 2. The image generating machine according to claim 1, wherein the cleaning means includes a pair of seal pieces brought into contact with both side edges of the circumferential surface of the photosensitive drum. 3. The image generator according to claim 2, wherein the seal piece is formed from a pile sheet piece. 4. The image generating machine according to claim 1, wherein the transfer sheet member is formed from a flexible synthetic resin sheet. 5. The image generator according to claim 1, wherein both the rotation output means and the rotation input means are comprised of gears.