US 3510903 A
Description (OCR text may contain errors)
y 12, 1970 H. o. STOEVER ETAL 3,510,903
ENDLES S CLEANING WEB Filed May 1, 1968 DEVELOPER STATION FIG.I
HANS O. STOEVER STEPHEN F. MICHATEK INVENTORS A2 @444 ATTORNEYS United States Patent 3,510,903 ENDLESS CLEANING WEB Hans O. Stoever and Stephen F. Michatek, Rochester,
N.Y., assignors to Eastman Kodak Company, Rochester, N .Y., a corporation of New Jersey Filed May 1, 1968, Ser. No. 725,742 Int. Cl. A471 25/08; B41f 35/00; G03g 1/22 U.S. Cl. 15-256.5 Claims ABSTRACT OF THE DISCLOSURE Residual toner particles on a photoconductive belt are cleaned therefrom by frictional engagement of a cleaning web running along an endless path in the opposite direction to the belt. The cleaning web itself is cleaned by a vacuum so that it may be reused.
BACKGROUND OF THE INVENTION Field of the invention This invention relates to a device for cleaning residual toner particles from a photoconductive surface, and more particularly a web, movable along an endless path, for cleaning a flexible photoconductive member. The web in turn is cleaned, as by a vacuum cleaning device.
Description of the prior art In a conventional electrophotographic apparatus, an electrostatic image is formed on a photoconductive surface. This image is then toned by a suitable developing material, such as a dry toner powder. The developed toner image is then transferred to a receiver. However, a small amount of residual toner will remain On the photoconductive surface which must be removed therefrom prior to the forming and transfer of subsequent images to prevent ghost images from being formed during subsequent transfers. Various attempts have been made to clean photoconductive surfaces. One is by means of a rotating brush. Brushes are usually made from fur of such animals as beaver, fox and rabbit and hence are relatively expensive. Also, brush cleaning can create a cloud of toner particles, as they are brushed from the photoconductor, which may settle on other parts of the machinery.
Another known method of cleaning a photoconductive surface is by the use of a web of material fed from a supply spool to a takeup spool with an intermediate portion thereof being brought into frictional engagement with the photoconductive material for cleaning. With this system,
the used web material must be replaced periodically with a clean roll of cleaning material. Unfortunately, the cleaning web may run out at a critical time, such as in the middle of a printing operation, requiring shut down of the machine at an inopportune time. If the web is changed when the machine is normally not in use, chances are that it will be changed before all of the cleaning web has been used, resulting in the loss of some unused material.
Another prior art device utilizes an endless web for recirculating toner from the photoconductor to the toning station.
SUMMARY OF THE INVENTION In accordance with this invention, a web, movable along an endless path, is provided which frictionally contacts a photoconductive surface to remove residual toner particles therefrom which are collected on the web. The web is then cleaned by a vacuum device which pulls air therethrough removing toner particles thereon. Thus, the Web may be used over and over again without replace'- ment for a substantial period of time. When replacement is necessary, it may be made when the machine is noranally shut down. In addition, the web may be made of 3,510,903 Patented May 12, 1970 ice any suitable low-cost pervious material, such as cheese cloth, terry cloth or other cloth having a close weave. The cleaning web may be brought in contact with the photoconductive surface along a line contact, over an extended surface or on a curved surface, as required.
Additional features of this invention will become ap parent from the description which follows taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with this invention, an electrographic mechanism M includes an endless photoconductive belt 10 which extends around spaced rollers 11 and 12 and may be driven by motor 13 through a drive belt 14. As is conventional in the art, photoconductive belt 10 may comprise an outer photoconductive surface on a conductive backing. The photoconductive belt is driven past a charging station 15, and exposure station 16, a developing station 17, a transfer station 18 and a novel web cleaning device D.
Cleaning device D includes a cleaning web movable along an endless path, such as endless cleaning web 19, which may be made of close woven pervious cloth material passing around a drive roller 21 and a series of pressure rollers 22 to bring a substantial area of the web into planar contact with photoconductive belt 10. A platen 23 is provided on the opposite side of photoconductive belt 10 to hold the belt in frictional contact with cleaning web 19. Advantageously, the cleaning web is driven in a direction opposite that of photoconductor 10. A shroud or housing 24 extends around a substantial portion of cleaning web 19, as shown, which is provided with an air inlet 25 and an air outlet 26 to which a vacuum may be applied to provide air moving means for cleaning toner particles from the web. Conveniently, inlet 25 is on the inside of the cleaning web and outlet 26 is on the outside of the web so that air is pulled through web 19 causing toner particles to be removed from the web so that it may be used over and over again to clean photoconductive belt 10. Thus, there is no necessity to frequently change the cleaning web nor will a long printing cycle need to be interrupted so that the web may be changed.
An alternative electrographic mechanism M. is shown in FIG. 2 wherein photoconductive belt 10' moves past a web cleaning device D'. In this device, a cleaning web 27 extends around a pressure roller 28 and a drive roller 29. The portion of cleaning web 27 which extends around pressure roller 28 is brought into line contact with photoconductive belt 10' which is held in frictional engagement with the cleaning web by a platen 23'. A shroud or housing 31 extends around Web 27 and is provided with an inlet 32 on the inside of web 27 and an outlet 33 on the outside of the web which is connected to a. vacuum for pulling air through the web to clean toner particles therefrom so that it may be used over a long period of time.
In the embodiment of FIG. 3, the photoconductive belt 10" of electrophotographic mechanism M is cleaned in the vicinity of roller 11" which serves as a platen to hold the photoconductor in frictional engagement with an endless cleaning web 34 which extends around a drive roller 35 and a pair of pressure rollers 36 and 37 as shown. These rollers serve to hold the cleaning web against the photoconductive belt over a substantial portion of the circumference of roller 11. A shroud 38 extends around the belt and is provided with an inlet 39 on the inside of the belt and an outlet 40 on the outside thereof which is attached to a vacuum so that air may be pulled through the web to clean toner particles therefrom which have been cleaned from the photoconductor.
From the foregoing, the advantages of this invention are readily apparent. A cleaning device has been provided l so that it may be used over and over again. In the embodiment of FIG. 1, the web engages the photoconductor over a substantial area and is backed up by a relatively fiat platen. In the embodiment of FIG. 2 line contact is made between the cleaning web and photoconductor, the latter being backed up by substantially planar platen. In FIG. 3,
the cleaning web passes over a substantial portion ofthe photoconductor wherein a large roller serves as a backup platen.
The invention has been described in considerable detail with reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
What is claimed is:
1. A cleaning device for cleaning residual toner particles from a photoconductive surface, said device comprising:
a pervious cleaning web having an inside surface and an outside surface; means for moving said cleaning web means for urging the outside surface of said cleaning Web into frictional rubbing contact with said photoconductive surface for cleaning the residual toner particles from said surface and collecting them on said cleaning web; and
means for moving air through said cleaning web to remove said residual toner particles therefrom.
2. A cleaning device, as claimed in claim 1, wherein said urging means brings 'said cleaning web into frictional engagement with said photoconductive surface along a line contact.
3. A cleaning device, as claimed in claim 1, wherein:
said urging means brings said web into frictional engagement withsaid photoconductive surface over a substantial area.
4. A cleaning device, as claimed in claim 3, wherein:
said urging means brings said cleaning web into contact with said photoconductive surface over a substantially planar area.
along an endless 5. A cleaning device, as claimed in claim 3, wherein:
said urging means brings said cleaning web into contact with said photoconductive surface over a substantially arcuate area.
6. A cleaning device, as claimed in claim 1, further including:
a backup platen for holding the photoconductive surface in frictional engagement with said cleaning web.
7. A cleaning device, as claimed in claim 6, wherein said platen is planar.
8. A cleaning device, as claimed in claim 6, wherein said platen is a roller.
9. A cleaning device for cleaning residual toner particles from a photoconductive belt, said device including:
an endless cleaning belt;
drive means for moving said endless belt through an endless path;
means for urging said cleaning web into frictional contact with said photoconductive belt for cleaning said toner particles therefrom and collecting them on said cleaning web;
a shroud substantially surrounding said cleaning web and having an inlet on one side of said web and an outlet on the other side of said web, said outlet being connectable to a vacuum producing means so that air may be drawn in through said inlet and through said cleaning web so that residual toner particles thereon will be removed therefrom and carried through said outlet.
10. A cleaning device as claimed in claim 1 wherein said air moving means includes:
a shroud substantially surrounding a portion of said cleaning web to be cleaned, said shroud having air inlet means adjacent the inside of said cleaning web and having air outlet means adjacent the outside of said cleaning web so that means may be applied to said shroud to move air in said inlet and through said web and out said outlet to dislodge toner particles from said web to be removed through said outlet by said moving air.
References Cited UNITED STATES PATENTS 3,298,904 1/1967 Le Compte 134-15 X 3,074,086 1/1963 Remer 15-1.5 3,411,932 11/1968 Malone et a1 151.5 X 2,832,977 5/1958 Walkup et a1. 15--1.5
FOREIGN PATENTS 319,208 3/ 1926 Germany. 137,012 7/1959 U.S.S.R.
WALTER A. 'SCHEEL, Primary Examiner L. G. MACHLIN, Assistant Examiner US. 01. X.R. 355-15