US 3908594 A
A marking apparatus for a material to be marked with an electrophotosensitive layer comprises means for feeding the material, a developing roller having a resilient, nonconductive surface layer, said roller being so mounted as to contact only with the material, and a suction means for sucking an excessive developer after developing with a time interval necessary for acccomplishing developing operation.
Claims available in
Description (OCR text may contain errors)
United States Patent 11 1 Matsumoto et a1.
[ MARKING APPARATUS  inventors: Seiii Matsumoto; Satoru Honjo;
Kazuhiro Kawaziri; Sigeru Tezuka; Etuo Shiozawa, all of Asaka. Japan  Assignee: Fuji Photo Film Co.. Ltd.. Minamiashigara, Japan 122] Filed: Mar. 30, 1973 [211 Appl. No.: 346,292
 Foreign Application Priority Data Apr. 3. 1972 Japan 47-33371  U.S. Cl. 118/637; 118/70; 118/104;
ll8/D1G. 23  Int. Cl. (303G 13/10  Field of Search 118/70, 104, DIG. 23,, 637
156] References Cited UNITED STATES PATENTS 3.363.530 1/1968 Rice 118/637 X 1 51 Sept. 30, 1975 3.369.523 2/1968 Naumann 118/637 3.410.713 11/1968 Schneidercit... ll8/D1G. 23
3.461.843 8/1969 Noon ll8/D1G. 23 3.552.353 1/1971 Labombarde 118/70 3.701.337 10/1972 Borelli et a1. 118/637 3.741.157 6/1973 Krause 118/637 3.741.643 6/1973 Smith ct al.. 355/10 3.830.199 8/1974 Saito et a1 1 18/637 Primarv E.\'aminerMervin Stein Attorney. Agent, or Firm-Gerald J. Ferguson, Jr.; Joseph J. Baker  ABSTRACT A marking apparatus for a material to be marked with an electrophotosensitive layer comprises means for feeding the material, a developing roller having a resilient. nonconductive surface layer, said roller being so mounted as to contact only with the material, and a suction means for sucking an excessive developer after developing with a time interval necessary for acccomplishing developing operation.
12 Claims, 10 Drawing Figures Patent Sept. 30,1975 Sheet 1 of3 3,908,594
Lilllllllllllllll FIG. IB
Lllllllllllllllll LLIIIIIIIIYIIIIIIILB' FIG. IC
T0 NOZZLE 5|||||i||l||||||||l|| 7 U.S. Patent Sept. 30,1975 Sheet 2 of3 3,908,594
T0 NOZZLE p 3 |||||||ll||||||\|' US. Patent sfipt. 30,1975 Sheet 3 of3 3,908,594
W71 -fi ZLIHIIIII HR? FIG.
L ZilllllllllifllllllIK- MARKING APPARATUS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a line marking apparatus on a sheet material such as steel plate.
It is troublesome to form mark lines on a surface of steel plate or the like and an automatic marking by utilizing an electrophotographic technique has highly been desired. It is, however very difficult to apply a developer only in the necessary range of a surface of material to be marked during feeding the material by conveyor.
An object of the invention is to provide an apparatus for forming marked lines on a surface of material to be marked by coating an electrophotographic light sensitive layer thereon and forming an information such as marked lines with an electrophotographic process.
Other features and advantages of the invention will be made apparent from the following description of preferred embodiments thereof taken in conjunction with the accompanying drawings.
2. Brief Description of the Drawings FIG. 1 is a schematic side elevation of one embodiment of the invention where FIG. 1A illustrates a charging step, FIG. 18 illustrates an image exposure step, and FIG. 1C illustrates a developing and cleaning step in accordance with the invention and FIGS. 2 to 8 are schematic side elevations of the essential parts of embodiments in accordance with the invention respectively.
DETAILED DESCRIPTION OF THE EMBODIMENTS FIG. 1A, 1B and 1C represent devices performing the inventive processes in which FIG. 1A is a charging process, FIG. 18 an exposure process and FIG. 1C a developing process. In FIG. 1A, numeral 3 represents a material to be marked made of, for example, a steel plate and a light sensitive layer 2 (the layer is made of photoconductive powder material such as zinc oxide or titanium oxide mixed with a resin having high insulating property such as silicon acrylic resin or alkyd resin and is applied on the surface about from 5 to 30a in thickness). Numeral 4 is a corona discharge electrode of which size is about from 30 to 100 in diameter. The .plate like material 3 to be marked is fed with a conveyor 7 in the direction shown by an arrow and the material is charged with the electrode 4 during passing under the electrode.
As shown in FIG. 1B, an original 5 having an original draft, such as marking lines thereon is superposed on the light sensitive layer 2, exposing them to a suitable light source 6, thus forming an electrostatic latent image in the light sensitive layer 2.
The material to be marked having the latent image is fed to the developing station shown in FIG. 1C. As seen in FIG. 1C, a developing roller 8 having a resilient, porous and electrically insulating surface in-which liquid developer being infiltrated is driven on the surface having the latent image under a suitable pressure to develop the image. The roller 8 is so constructed that has a core made of metal, vinyl chloride or acrylic resin and a urethane foam band 0.5 to 10 cm in thickness wound thereon. As a liquid developer, Kerosene, lsopar E, H or G (isoparafil solvent) or cyclohexane or the like in which carbon black, phthalocyanine blue, as a pigment,
being dispersed with suitable charge adjusting agent. After passing through the roller 8, the excessive developer is absorbed with a suction roller 9, drying with air ejected from a nozzle 10.
In FIG. 2, an embodiment of an apparatus for applying developer onto the light sensitive layer 2 is shown. The roller 8 is, as set forth above, formed with a core made of metal or vinyl chloride or acrylic resin and a surface layer made of polyurethane foam, polyethylene foam or rubber foam which is resilient, porous and having a high insulating property. The material 3 to be marked fed with the conveyor 7 passes through under the roller 8 to receive the developer by squeezing thereof due to compression of the roller onto the material surface. According to be advance of the material and the rotation of the roller 8, the excess developer supplied on the material surface can be absorbed into the roller again upon leaving from the material surface, so that a suitable amount of developer may be applied on the surface.
It is preferable that the thickness of the material to be marked is more than a radially compressed distance of the resilient portion of the roller for assuring proper supply of liquid developer. According to our experi ments, a material to be marked having a thickness of more than 3 mm makes it. possible to proper developer supply only in the necessary area for marking without any excess supply into the unnecessary area. When a thickness of material to be marked is less than 3 mm, a plate member having about the same size with the material is positioned on the conveyor and the material is superposed on the plate member to make the total thickness of them more than 3 mm.
As set forth above, by making a hight of a material to be marked substantially more than 3 mm a proper amount of developer can be applied to only a necessary area with compressed drive of the porous developing roller having liquid developer therein.
In FIG. 2, numeral 21 represents an arm on which the roller 8 being rotatably mounted at its one end and the arm is also swingably mounted by means of a pin 22 at its other end. When lacking in developer, the roller may be rotated to a position shown by numeral 8'. Numeral 23 is a nozzle for supplying developer to the roller and during supplying developer the roller rotates in the direction shown by an arrow. Numeral 24 is a squeezing roller for removing'an excessive developer. The excessive developer will be collected in a reservoir R through a tray 25. The developer withdrown into the reservoir R will be fed to the nozzle 23 by means of a pump P.
After developer supplying operation has finished the roller 8 will be returned to its operating position from said developer supply position. During the roller is in the supply position, the conveyor 7 is stopped.
FIG. 3 shows a schematic elevational view of another embodiment in accordance with the invention in which a plate like material to be marked is fed in constant speed in the direction shown by an arrow. A light sensitive layer 2 has a latent image therein formed during passing through a charge and an exposure process. A developing roller 8 having a resilient, porous surface layer rotates around a shaft thereof. During passing the material 3 under the roller 8 having a developer therein with a suitable compression of the resilient surface layer of the roller, the developer in the roller 8 is applied onto the light sensitive layer 2 of the material.
Upon leaving from the roller surface an excessive amount of the developer on the material will be absorbed to the roller layer again, so that a proper amount of the developer can always be applied onto the light sensitive layer 2.
Since the surface of the roller 8 has sufficient resiliency, it completely compensates for a slight roughness due to a roughness of the material surface and minimizes irregularity of developer supply. If the material to be marked has a thickness of more than 3 mm, the outer porous surface layer of the roller is not compressed when it never contacts with any other ones than the material and thus useless comsumption of developer does not occur.
Numeral 31 represents a developer supply nozzle, numeral 32 is a squeezing roller for retaining a proper amount of developer in the roller layer.
An excess developer, over flown and squeezed from the roller will be collected in a reservoir R through a tray 33. Numeral 34 is a doctor blade for preventing an excess developer from adhering to the roller again. The squeezing roller may be driven with a motor (not shown) or the roller 8.
An amount of developer about from 0.1 to 0.8 c.c./cm in the roller layer is preferable, a less developer causes insuficient development and an excessive one stains the surface of the marked surface.
A preferable amount of a developer to be supplied from the roller is determined in accordance with an amount of toner included in the developer and when an amount of the developer having toner X g/l in the range of to 500 c.c./m a preferable amount of the developer to be supplied onto the photosensitive surface can be indicated by the following expression:
l X IOOOX (40 X )cc/m For example, a preferable amount of developer, when including 4 g/l toner weight, is about from to 250 c.c./m developer of about from to 500 c.c./m when including 2 g/l of toner, developer about from 40 to 500 c.c./m when including 1 g/l of toner, developer about from 5 to 125 c.c./m when including 8 g/l of toner and developer about from 5 to 100 c.c./m when including 16 g/l toner.
A blurred image may be obtained with too less developer and an excess developer stains a light sensitive surface and is wasteful.
As the porous member of the roller has sufficient resiliency, it compensates for a slight unevenness of a light sensitive surface of a material due, for example, to a roughness of the surface of the material, for inaccuracy of a conveyor and the like. According to our experiments, porous member having bubles of which di ameters are in the range of from 50 to 900a could retain the optimum amount of developer and a roller of which diameter was of about from to 400 mm was the most proper for use.
A developer contained in a roller tends to drop out therefrom due to the existence of gravity when stopping the roller, and if not drop out the developer is apt to collect in the under space of the roller. Thus, it is de sirable to rotate the roller continuously not only during supplying the developer to the material but also during idling. It is preferable to rotate the roller more than 10 rpm. during there is no contact of the roller with a material.
FIG. 4 represents an embodiment of a suction roller which sucks a developer already used after the developer has been applied to a material to be marked. After a developer has been applied to a photosensitive layer on a material to be marked and a latent image has been developed, the material is fed to a position where a suction roller is mounted about 5 to 200 cm from the developing roller. Used developer is removed from the material by the suction roller.
The suction roller 9 has a core made of metal, plastic or others and a resilient, porous and a high oil absorbing layer made of, for example, polyethylene foam layer mounted around the core. Bubbles contained in the suction roller having substantially similar to or slightly less than that of the developing roller in sizes, namely about 30 to 700g in diameter can preferably be used. Such suction roller will remove used developer promptly and sufficiently. The diameter of the suction roller of about 2.5 to 40 cm is optimum. Numeral 41 is a suction nozzle which removes the developer already sucked developer to the roller. The sip slit of the nozzle about 2 to 20 mm in width and a pressure of from 400 to 1000 mm water head in a suction pump P are preferable.
Thus, even if there is a sight roughness on a surface of a material to be marked, most of used developer can be removed by means of suction effects of a suction roller and a suction pump for preventing the developer from collecting in the suction roller.
It is preferable to determine a position at which the suction roller is to be positioned so that the suction roller contacts with used developer on the material to be marked about 0.5 to 20 seconds later after developing operation has finished. Therefore, the position is about 5 to 200 cm far from the developing position when the conveyor velocity is 10 cm/sec.
FIG. 5 represents another embodiment of a suction roller device. Used developer can be absorbed into a porous layer of a suction roller 9 through a nozzle 51 and then sucked with a suction pump P. Numeral 52 is a rotatable roller mounted at the slit of the nozzle 51 for squeezing the developer in the roller 9. This rotatable roller 52 not only sucks the developer in the roller 9 effectively but also prevents wear of the porous layer of the roller 9.
FIG. 6 represents further embodiment of a suction roller device. A hollow tube like casing 62 having 212'. axially formed opening has an inner tube 6i having a plurality of small holes and the exposed portion of the inner tube is forcibly in contact with the porous surface of the suction roller 9 for sucking used developer through the opening as shown in the figure. The central hollow portion inside the tube 61 is maintained a negative pressure with a suction pump (not shown), so that used developer can be sucked into the hollow portion. The numeral 62 is the casing for preventing entrainment of air from the holes which are not in contact with the suction roller 9. Numeral 63 is a trough for collecting sucked developer.
FIG. 7 represents a device for use in a drying process. Numeral 71 is an air nozzle positioned above the light sensitive surface being fed by a conveyor 7 about 2 to 30 mm and effects squeezing and drying the remained developer. An excessively high air velocity tends to damage an image formed on the material to be marked and a too less velocity causes less effect. A velocity of the air flow in the range of from 0.5 to m/sec and a direction of the air flow in the angular range of from 45 to 90 to the surface of the material to be marked is preferable.
FIG. 8 represents another embodiment of a drying process. A suction roller 9 is in the proximity of an air nozzle 81 for increasing suction effect of the roller. The suction roller has a porous and resilient surface layer and the surface is in contact with a light sensitive layer 2. Accompanying with the rotation of the roller 9, sucked developer into the roller is then sucked into a nozzle 41 and residual returns to the roller 9 due to an air flow from the nozzle 81 and sucked into the roller 9. It is of course that the air flow ejected from the nozzle 81 enaporate a part of residual.
The distance between the line that the contact line of the suction nozzle 9 with the surface of the material to be marked and the line that the air flow ejected from the nozzle 81 runs against the surface of the material is preferably about from 3 to 50 mm. The angle between the air fiow ejecting direction and the. material surface direction is preferably decided in the range of 45 to 90.
As set forth above, according to the invention the marking operation on an electroconductive material being more than 3 mm in thickness can effectively be carried out.
It is course that two or more developing rollers, suction rollers and air nozzles raise a developing and a drying effects.
According to the invention, a high contrast marked line image can be obtained with minimum developer loss on materials to be marked of various dimensions and further a photosensitive layer is upwardly directed, so that no troubles in mechanical system, especially in exposure system, are encountered.
Although the invention has been described in its preferred form with a certain degree of particularity, it should be understood that the present disclosure has been made only by way of example and various changes may be resorted to without departing from the spirit of the invention and the scope of the invention as hereinafter claimed.
What is claimed is:
1. ln apparatus for marking a metallic plate having a surface electrophotosensitive layer theron by charging said layer, image exposing to form a latent image, and developing said latent image, the improvement of a conveyor belt for feeding said metallic plate disposed on one side thereof, a developing roller disposed on the other side of said metallic plate and directly opposite to at least a portion of said conveyor belt having a porous, sponge like, non-conductive surface layer, said roller being so mounted as not to contact said conveyor belt but to contact said electrophotosensitive layer of the metallic plate with at least the under side of the sponge like surface layer, said sponge like surface containing a liquid developer for effecting said developing as it is squeezed against said electrophotosensitive layer and suction means for removing excessive developer from said metallic plate after a time lag necessary to complete the developing operation.
2. The improvement in claim 1 where said image to be developed is a line image.
3. The improvement of claim 1 where said developing roller has a diameter of 2.54() cm, and includes a solid core covered with said sponge like layer having a thickness of 0.5-10 cm.
4. The improvement as in claim 1 where the bubbles contained in said sponge like layer have a diameter in the range of 50 to 900 1..
5. The improvement as in claim 1 including means for supplying developer directly onto the surface of the sponge like layer.
6. The improvement as in claim 1 where the suction means comprises a suction roller having a core and a resilient, porous layer mounted thereon, which is pressed against the material to be marked.
7. The improvement as in claim 6 where the outside diameter of said suction roller is 25-40 cm.
8. The improvement as in claim 6 where said suction means includes a suction nozzle to absorb the developer contained in the suction roller layer, said nozzle being pressed against the surface of the porous layer.
9. The improvement as in claim 8 including a roller rotatably mounted within said suction nozzle for squeezing the developer in said suction roller layer.
10. The improvement as in claim 1 including means for insuring that said material to be marked is greater in thickness than the radial compression of said sponge like layer as the latter squeezes against said electrophotosensitive layer.
11. The improvement as in claim 1 where said material to be marked is greater in thickness than the radial compression of said sponge like layer as the latter squeezes against said electrophotosensitive layer.
12. The improvement as in claim 1 where said sponge like layer contains about 0.1 to 0.8 c.c./cm of said de-