CA1069578A - Construction of a photosensitive drum - Google Patents

Construction of a photosensitive drum

Info

Publication number
CA1069578A
CA1069578A CA242,292A CA242292A CA1069578A CA 1069578 A CA1069578 A CA 1069578A CA 242292 A CA242292 A CA 242292A CA 1069578 A CA1069578 A CA 1069578A
Authority
CA
Canada
Prior art keywords
drum
roller
edge portions
peripheral
photosensitive drum
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA242,292A
Other languages
French (fr)
Inventor
Toshio Hayashi
Sunao Ikeda
Tatsuo Tani
Kenzo Ariyama
Osamu Haruyama
Tatsuro Oka
Shinzi Nagatsuna
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ricoh Co Ltd filed Critical Ricoh Co Ltd
Application granted granted Critical
Publication of CA1069578A publication Critical patent/CA1069578A/en
Expired legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00Apparatus for electrographic processes using a charge pattern
    • G03G15/75Details relating to xerographic drum, band or plate, e.g. replacing, testing
    • G03G15/751Details relating to xerographic drum, band or plate, e.g. replacing, testing relating to drum
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00Apparatus for electrographic processes using a charge pattern
    • G03G15/06Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/10Apparatus for electrographic processes using a charge pattern for developing using a liquid developer
    • G03G15/11Removing excess liquid developer, e.g. by heat

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Wet Developing In Electrophotography (AREA)
  • Photoreceptors In Electrophotography (AREA)
  • Discharging, Photosensitive Material Shape In Electrophotography (AREA)
  • Rolls And Other Rotary Bodies (AREA)

Abstract

CONSTRUCTION OF A PHOTOSENSITIVE DRUM

ABSTRACT OF THE DISCLOSURE
A photosensitive drum for use in electro-photographic apparatus of wet developing type comprising an excess developing solution removal roller which is jux-taposed to the drum with a given spacing by act of a pair of bearing rollers being in rolling contact with lateral edge portions of the peripheral durm surface. The above edge portions are coated with a layer or film of a material such as alumite, stainless steel, etc. for abrasion prevent-ing purpose to thereby preserve the operation of the removal roller.

Description

BACKGROIJND OF THE INV~:NTION
The invention relates to the construction o~ a photosensitive drum which i~ used in an electrophoto-graphic apparatus of wet developing type.

_IEF DESCRIPTION OF THE DRAWINGS

~ igo 1 i8 a schematlc side elevation of a conventional electrophotographic mahine including a photo-sensitive drum and related parts;
Fig. 2 is a front view of an apparatus for ., removing an excess amount of developing solution, the photo-sensitive drum being shown as constructed in accordance wlth the prior art practice;
~ ig. 3 iB a fragmentary perspective view of the apparatus for removing an excess amount of developing solutlon, the photosensitive drum shown being con~tructed in accordance with one embodiment of the present invention;
~ ig. 4 18 a fragmentary cross section of the apparatus shown in Fig. 3; and Fig. 5 is a fragmentary section illustrating another embodlment of the photosensitive drum.

AB illustrated in ~ig. 1, in a ~et develop-ing proCesB ~ a photosensitive drum 1 is charged at a charing station 2, and is exposed to projected light to have an electrostatic latent image formed thereon, which image iB converted into a visual image at a'developing ' station 4. A~ter an excess amount of developing solution which remains on the photosen~itive drum 1 is removed by a roller 5, the visual lmage on the drum is transferred onto a transfer sheet 7 by means of a transfer charger S, and the transfer sheet iB separated from the drum at a separating station 8.

7 ~

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~ ~ ~7 ~
The remo~al of t~e exces~ amou~t of develop-irlg ~olution from the photosensitivë drum 1 takes place in the manner illustrated in Fig. 2. Specifically, the roller 5 is located ad~acent to the drum 1 with a given spacing t therebetween. A pair of bearing rollers 9 of diameter which is by 2t greater than that o~ the roller 5 are concentrically mounted on the opposit~ ends of a rotating shaft 11 which carries the roller 5. ~he rotat-ing shaft 11 is supported by a pair of bearing~ 12, and a compre~ion ~pring 14 interpo~ed between each of the bearing 12 and a stationary member 13 urges the bearing rollers 9 again~t the drum ~ur~ace along itB oppoBite lat-eral edges. ~he drum 1 and the roller 5 are driven counter-clockwise, as viewed in Fig. 1, whereby any exces~ amount of developing ~olutlon which i8 carried on the drum sur-fsce 18 removed as it passes through the close spacing t.
As mentioned previously, the bearing rollers 9 rotate in the opposite direction from that of the drum 1 wh~le bearing against the latter. A conventional photo-sensitive drum is made from a variety of materials taking into consideration the requirement for a reduced weight.
In one example, the drum is integrally molded from alumin-ium, and is then machined to a required configuration.
~hereupon, a photo~ensltive layer of a material such as selenium, for example, ie formed on the peripheral surface of the drum. When the drum 1 is made from a relatively ~oft material in this manner, the lateral edge region~ la of the drum will be sub~ected to abrasion because of the con~tant abutting engagement with the bearing rollers 9 which are made of a relatively hard material. As the abra-slon proceeds, the spacing t formed between the drum 1 and the roller 5 will decrease gradually, eventually causlng a serious lnfluence upon the image formed on the drum 1 ~ o6g~7~
such as erasure or distortion of the image.

SlJMMARY OF THE INVENTION

It is an object of the lnvention to over-come the abovementioned di~advantage of the prior art by providing a photosensitive drum of a ~imple construction which maintains a uniform effect in the removal of an exce~s amount of developing ~olution.
More particularly, there is provided:
in electrophot~graphic apparatus of wet developing type comprising a photosensitive drum supported for rotation and having a photosensitive layer formed on the peripheral surface thereof and an excess developing solution removal de-vice comprising an excess solution removal roller juxtaposed to said drum for rotation, means for urging said roller toward said drum and a pair of bearing rollers rotatably and concen-trically mounted on opposite ends of said removal roller so as to be in rolling contact with respective lateral edge portions of said peripheral drum surface to thereby maintain a given spacing between said drum and said removal roller, said photo-sensitive drum comprising a aluminum drum body and an abrasionpreventing layer formed of oxidized alumite and having a hardness greater than that of said drum body and coated .n said lateral edge portions of said peripheral drum surface.

DETAILED D~S~RIP~ION 0~ ~MBODIMENTS

Referring to ~ig. 3, there is shown a photo-8ensiti~e drum 21 which is constructed in accordance with one embodiment of the invention. Specifically, the oppo-~ite lateral edge regions of the peripherary of the drum are uniformly formed with a haxdened layer 22 of a given thic~ne88. The hardened layer may be iormed $n a number \~l - ...

~0~957~3 of ways. In one example, where the drum 21 18 formed of allLminium, the drum surface may be oxldized ln the region of the lateral edge8 to form an alumite Yilm which exhlb$ts a hlgh resistance to abrasion.
Referring to Fig. 4, the peripheral surrace -4a-7~

of the photoaensitlve drum 21 iR formed with a photosensi-tive layer 21a of a material such a~ selenium, for example, in its region located opposite to a roller 2~, which i~
clo~ely spaced therefrom with a given spacing t. Mounted on the opposite ends of a rotating shaft 25 which carries the roller 23 are a palr of rolling bearing~ 24 in concen-tric manner with the roller 23. The rolling bearings 24 are posltioned so a~ to bear against the hard0ned layer 22 on the photosensitive drum 21, and hav~e an outer dia-meter which i9 sized 80 that the spacing formed betweenthe roller 23 and the photosensitive layer 21a is equal to a given value t.
As shown in Fig. ~, the drum 21 rotates in the counterclockwise direction, indicated by an arrow A, a~ does the roller 23, whereby any excess amount of devel-oping eolutlon remainlng on the drum 21 i8 removed as it passee through the spacing t therebetween. The rolling bearin~ 24 which bear against the hardened layer 22 on the drum 21 rotate in a direction indicated by an arrow ~, as the drum 21 rotates. ~he pro~ision of the hardened layers 22 on the opposite lateral edge region~ of the drum prevents or minimizes the abrasion of the material of the drum. The similar effect can be achieved by providing a highly hard member 26 such as a stainless steel, for example, on the opposlte lateral edge regions of the drum 21, as illustrated in Fig. 5.

:: . : , . ..

. ; :, .

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In electrophotographic apparatus of wet developing type comprising a photosensitive drum supported for rotation and having a photosensitive layer formed on the peripheral surface thereof and an excess developing solution removal de-vice comprising an excess solution removal roller juxtaposed to said drum for rotation, means for urging said roller toward said drum and a pair of bearing rollers rotatably and concen-trically mounted on opposite ends of said removal roller so as to be in rolling contact with respective lateral edge portions of said peripheral drum surface to thereby maintain a given spacing between said drum and said removal roller, said photo-sensitive drum comprising a aluminum drum body and an abrasion preventing layer formed of oxidized alumite and having a hardness greater than that of said drum body and coated on said lateral edge portions of said peripheral drum surface.
CA242,292A 1974-12-28 1975-12-22 Construction of a photosensitive drum Expired CA1069578A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP129075A JPS5178333A (en) 1974-12-28 1974-12-28 KANKOTAIDORAMUNOKOZO

Publications (1)

Publication Number Publication Date
CA1069578A true CA1069578A (en) 1980-01-08

Family

ID=11497314

Family Applications (1)

Application Number Title Priority Date Filing Date
CA242,292A Expired CA1069578A (en) 1974-12-28 1975-12-22 Construction of a photosensitive drum

Country Status (4)

Country Link
JP (1) JPS5178333A (en)
CA (1) CA1069578A (en)
DE (1) DE2558451C2 (en)
GB (1) GB1481003A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5854960A (en) * 1994-10-28 1998-12-29 Indigo N.V. Squeegee roller for imaging systems

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53103737U (en) * 1977-01-26 1978-08-21
JPS5819565Y2 (en) * 1978-12-22 1983-04-22 株式会社東芝 Photosensitive drum for electrophotography
US4364661A (en) * 1980-05-13 1982-12-21 Savin Corporation Process and apparatus for transferring developed electrostatic images to a carrier sheet, improved carrier sheet for use in the process and method of making the same
JPS5778068U (en) * 1980-10-30 1982-05-14
DE3213797A1 (en) * 1982-04-15 1983-10-20 Hoechst Ag, 6230 Frankfurt ELECTROPHOTOGRAPHIC COPYING METHOD AND DEVICE FOR REMOVING THE DEVELOPER LIQUID FROM A PHOTO CONDUCTOR SURFACE
DE3213798A1 (en) * 1982-04-15 1983-10-20 Hoechst Ag, 6230 Frankfurt ELECTROPHOTOGRAPHIC COPYING METHOD FOR REMOVING DEVELOPER LIQUID FROM A PHOTO CONDUCTOR SURFACE
JPS62113111U (en) * 1986-01-06 1987-07-18
JPS6311665U (en) * 1986-07-07 1988-01-26
US5369477A (en) * 1993-12-07 1994-11-29 Hewlett-Packard Company Liquid electrophotography fluid containment and belt tracking device

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE514705A (en) * 1951-06-25
BE628026A (en) * 1962-02-08
US3367852A (en) * 1964-10-29 1968-02-06 United Aircraft Corp Selected area hardcoating of aluminum
GB1198497A (en) * 1966-11-15 1970-07-15 Fuji Photo Film Co Ltd Electrophotographic Print Marking Process for Metallic Materials
US3684368A (en) * 1968-07-10 1972-08-15 Hitachi Ltd Xerographic apparatus
US3524799A (en) * 1969-06-13 1970-08-18 Reynolds Metals Co Anodizing aluminum
CA964053A (en) * 1971-07-08 1975-03-11 Kazumi Umezawa Liquid developing device in electrophotographic copying apparatus
JPS5022637A (en) * 1973-06-26 1975-03-11

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5854960A (en) * 1994-10-28 1998-12-29 Indigo N.V. Squeegee roller for imaging systems

Also Published As

Publication number Publication date
JPS5178333A (en) 1976-07-07
JPS5746551B2 (en) 1982-10-04
GB1481003A (en) 1977-07-27
DE2558451C2 (en) 1981-09-24
DE2558451A1 (en) 1976-07-01

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Legal Events

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