Patent Grant
7784177
This application claims priority from Korean Patent Application No. 10-2005-0125203, filed on Dec. 19, 2005, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to an image drum for use in a printing apparatus, and more particularly, to an image drum and a method of manufacturing the same, in which an image drum including a ring conductor can be easily fabricated and a manufacturing cost can be reduced.
2. Description of Related Art
Referring to
An elongate-shaped control unit 16 is mounted inside of the hollow drum body 12 such that a terminal array 18 formed at a longitudinal edge of the control unit 16 adjoins the internal wall of the drum body 12. The control unit 16 is arranged for individually applying a suitably high voltage to each of the electrodes 14 via the terminal array 18 in accordance with the image formation. As shown in
In order to manufacture the image-forming element 10, the cylindrical drum body 12 is provided. The grooves are cut into the outer circumferential surface of the drum body 12, for example by means of a diamond chisel to have a pitch of approximately 40 μm and a width of approximately 20 μm to form the electrodes 14. Alternatively, these grooves may be formed on the outer circumferential surface of the drum body 12 by means of a laser beam or an electron beam.
In the next step, the large diameter holes 26 are cut into the wall of the drum body 12 from inside by, for example, a laser beam. The small diameter holes 24 may also be formed with a laser beam, either from the inside or outside of the drum body 12 to thereby form the through-holes 22. After the through-holes 22 including the small diameter holes 24 and the large diameter holes 26 have been formed, the whole drum body 12 is anodized so as to form the insulating metal oxide layer 34 on the whole surface of the drum body 12. Thereafter, the electrically conductive material 32 fills in the grooves and the through-holes 22. The outer or inner circumferential surface of the drum body 12 is cut to a predetermined depth through polishing so as to effectuate the electrodes 14 and electrical connection portions inside of the through-holes 22. An insulating layer is formed on the outer circumferential surface of the drum body 12 and the control unit 16 is disposed inside of the drum body 12 so as to complete the manufacture of the image-forming element 10.
As described above, in order to form the electrodes 14 on the outer circumferential surface of the drum body 12, the grooves are densely formed over the whole length of the drum body 12 using a precise cutting tool and the through-holes 22 must be formed at regular intervals either from the inside or outside of the drum body 12. Also, after the formation of the anodized surface layer on the outer circumferential surface of the drum body 12 and at the internal wall of the through-holes 22, the electrically conductive material 32 is filled into the grooves and the through-holes 22 and is removed until a desired thickness remains. Specifically, since it is very difficult to evenly form the grooves on the outer circumferential surface of the drum body 12 in such a fashion as to have a pitch of approximately 40 μm and a width of approximately 20 μm and to fabricate the through-holes 22, a manufacturing cost of the image-forming element 10 is significantly high and defect regularly occur. However, the conventional image-forming method and apparatus entails a problem in that a printer made by using such a method and apparatus is expensive, which makes it difficult to sell the printer. As discussed in detail below, there is presently disclosed a direct induction type image-forming method and apparatus using a ring conductor such as the image-forming element described above.
Additional aspects and/or advantages of the invention will be set forth in the description which follows and in the accompanying drawings. Illustrative, non-limiting embodiments of the present invention overcome the above disadvantages and other disadvantages not described above. Also, the present invention is not required to overcome the disadvantages described above, and an illustrative, non-limiting embodiment of the present invention may not overcome any of the problems described above
The present invention provides an image drum which can reduce the complexity of a conventional manufacturing process and also decrease the manufacturing cost by forming ring electrodes on the outer circumferential surface of a drum body through injection molding, in a shape to include a control unit in the drum body, and a method of manufacturing the image drum.
The present invention also provides an image drum which can form a control unit by using a printed circuit board (PCB) or a flexible printed circuit board (FPCB), electrically connect a conductive pattern with each of the ring electrodes, and individually apply a voltage to each terminal and control the voltage of the ring electrodes, and a method of manufacturing the image drum.
The present invention also provides an image drum which can integrally form gears in both ends of a drum body by injection molding and reduce a manufacturing process, and a method of manufacturing the image drum.
According to an aspect of the present invention, an image drum manufacturing method provides a hollow cylindrical mold having a plurality of mold grooves circumferentially cut in its inner circumferential surface and a core portion having a smaller diameter than a hollow of the mold and having a slit-shaped combination groove.
After this, a conductive material fills in the mold grooves of the mold. In this instance, the conductive material may be an electrically conductive metal. According to another aspect of the present invention, in addition to a metal, another electrically conductive material may be utilized. As an example, a silver paste or a conductive polymer may be utilized.
Also, a control unit is inserted into the combination groove such that the control unit is partially exposed to an outside of the core portion. In this instance, the control unit is exposed according to the difference in size between the core portion and the hollow of the mold. Also, the control unit individually applies a voltage to each terminal, and is formed in the mold groove and controls each ring electrode which is made of a conductive material.
The core portion is inserted into the mold after coupling the control unit with the combination groove. The core portion is positioned to closely adhere an end of the control unit to the mold groove.
The drum body is formed to receive the control unit by initially inserting the core portion into the mold and subsequently filling a molten plastic into an opening (a space) between the mold and the core portion.
In order to form ring electrodes on the outer circumferential surface of a conventional drum body, grooves are densely formed over the whole length of the drum body using a precise cutting tool and through-holes must be formed at regular intervals either from the inside or outside of the drum body. Also, after the formation of the anodized surface layer on the outer circumferential surface of the drum body and at the internal wall of the through-holes, an electrically conductive material is filled into the grooves and the through-holes and is removed until a desired thickness remains. Specifically, since it is very difficult to evenly form the grooves on the outer circumferential surface of the drum body to have a pitch of approximately 40 μm and a width of approximately 20 μm and to fabricate the through-holes in the conventional method, a manufacturing cost of an image-forming element is significantly high and defects regularly occur. As mentioned above, there is presently disclosed a direct induction type image-forming method and apparatus using a ring conductor such as the image-forming element as described above. However, the conventional image-forming method and apparatus entails a problem in that a printer made by using such a method and apparatus is expensive, which may make it difficult to sell the printer.
However, an image drum manufacturing method according to the present invention forms ring electrodes by filling a conductive material into mold grooves which are circumferentially cut in an inner circumferential surface of a mold, and provides the ring electrodes on an outer circumferential surface of a drum body. Accordingly, the grooves are formed in the mold to have a pitch of approximately 40 μm and a width of approximately 20 μm without using a conventional cutting tool for cutting each groove. Minute ring electrodes may be easily fabricated by a molding method using the grooves. The image drum manufacturing method may reduce a manufacturing process and a manufacturing cost, thus being very advantageous for mass production.
According to another aspect of the present invention, there is provided an image drum comprising: a core portion inserted into a mold for forming a drum body and formed with a combination groove; a control unit provided inside of the core portion using an FPCB, and a control unit guide having mold grooves corresponding to a plurality of circumferentially formed ring electrodes cut in an inner circumferential surface of the mold.
In this instance, a conductive pattern is printed on a surface of the control unit using the FPCB.
After printing the conductive pattern on the control unit, a control unit guide is provided in an end of the control unit so as to be closely adhered to the conductive pattern. In this instance, since the control unit utilizes the FPCB, bending may occur. However, since the control unit is initially provided with the control unit guide in its end and mounted to the mold, it is possible to prevent distortion, such as bending, of the control unit.
Next, the control unit mounted with the control unit guide is inserted into the combination groove.
Also, the core portion mounted with the control unit is inserted into the hollow of the mold such that ring electrodes correspond to the mold. A drum body is formed to receive the control unit by filling a molten plastic into a space between the mold and the core portion.
In this instance, the control unit may utilize the FPCB and a conductive pattern may be formed in a corresponding location of the control unit to each of the ring electrodes formed of a conductive material. Also, the control unit may utilize a PCB including a plurality of conductive patterns, and the conductive pattern is externally exposed. An insulating layer is formed on the conductive pattern, and connection holes are formed corresponding to ring electrodes formed of a conductive material. In this instance, the conductive pattern may be electrically connected with each ring electrode.
Accordingly, the control unit may more precisely perform an operation of selectively adsorbing toner so as to form an image in a printing apparatus. Also, the drum body may be formed by molding, such as combining the control unit with the combination groove of the core portion and inserting the core portion into the mold. Accordingly, the core portion may be stably received in the drum body, and a manufacturing process may be reduced.
According to still another aspect of the present invention, an image drum manufacturing method provides a hollow cylindrical mold having a plurality of mold grooves circumferentially cut in its inner circumferential surface and a core portion having a smaller diameter than a hollow of the mold and having a slit-shaped combination groove.
Subsequently, a conductive material fills in the mold grooves of the mold. In this instance, the conductive material fills in the hollow of the cylindrical mold and a piston body having an identical diameter to an inside of the hollow passes through the hollow to remove the conductive material except in the mold grooves, and the conductive material remains only in the mold grooves. The diameter of the piston body may be appropriately smaller than the inside diameter of the hollow, thereby ensuring an effective passage through the hollow of the cylindrical mold. However, according to another aspect of the present invention, a method of filling a conductive material only in mold grooves may be utilized according to a designer's preference.
After the above operation, the control unit which individually applies a voltage to each terminal and utilizes a PCB is included. Also, the control unit is inserted into the combination groove such that the control unit is partially exposed to an outside of the core portion.
A drum body is formed to receive the control unit by initially inserting the core portion into the mold and filling a molten plastic into an opening (a space) between the mold and the core portion. After this, an insulating layer is formed on a surface of the control unit.
Connection holes are formed on the insulating layer to correspond to ring electrodes made of a conductive material. The control unit is electrically connected with the ring electrodes via the connection holes. Accordingly, an image drum may be integrally formed with the control unit using a PCB.
The above and/or other aspects and advantages of the present invention will become apparent and more readily appreciated from the following detailed description, taken in conjunction with the accompanying drawings of which:
Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The exemplary embodiments are described below in order to explain the present invention by referring to the figures.
Referring to
The magnetic cutter 202 includes a rotary sleeve 224, and a magnet 222 disposed within the magnetic cutter 202 for applying an attraction force to the toner 1. The magnet 222 is positioned adjacent to the image drum 100, and can attract the toner 1 adhered to the surface of the image drum 100 using a magnetic force. The magnet 222 has a sufficient magnetic force which can collect the toner 1 from the electrodes of the image drum 100 which is not applied with a voltage. The toner 1 collected by the magnet 222 is fed back to the toner storage section or the toner feed roller 201 through the rotary sleeve 224.
The toner 1, which is not fed back to the toner storage section or the toner feed roller 201 by the magnetic cutter 202, is transferred to the image transfer section 230 from the outer circumferential surface of the image drum 100. Then, the toner 1 transferred to the image transfer section 230 is moved to a printing paper sheet which is in turn heat-treated so as to allow the toner 1 to be adhered to the surface of the printing paper sheet. The image drum 100 controls the voltage applied to the electrodes to conform to an image signal. Then, the image drum 100 generates an electrostatic force larger than that of the magnet 222 so as to prevent the toner 1 from being collected to the magnetic cutter 202.
Approximately five thousand electrodes are controlled individually so as to represent a two dimensional image on the image drum 100. The image represented on the image drum 100 through the toner 1 can be transferred to the printing paper sheet by using the image transfer section 230 as a relay means. After the toner 1 has been adhered to the surface of the printing paper sheet, the printing paper sheet passes through a heat-treatment apparatus. In this instance, the toner is adsorbed to the surface of the printing paper sheet to complete a corresponding printing.
As shown in
A plurality of ring electrodes 120 are integrally formed with the drum body 110 on the outer circumferential surface thereof by injection molding and electrically insulated from each other. Since the ring electrodes 120 can be formed by patterning copper or other thin conductive film in a flat state, a groove cutting process or a conductive material filling process employed in a conventional image drum manufacturing method may be eliminated in the present embodiment. First of all, since it is possible to form the ring electrodes 120 on the outer circumferential surface of the drum body 110 by injection molding, the level of work and difficulty are greatly reduced, as compared to forming the ring electrodes 120 on the outer circumferential surface of the cylindrical drum body 110. The defective generation rate of the ring electrodes 120 can be remarkably reduced.
The control unit 130 is fixed on the drum body 110 so as to be electrically connected with the ring electrodes 120 and individually applies a voltage to each of the ring electrodes 120. Conductive patterns may be formed on a top surface of the control unit 130. The conductive patterns are evenly formed as ring electrodes 120 to have a pitch of below approximately 40 μm and a width of approximately 20 μm. The ring electrodes 120 covering the circumference of the drum body 110 are formed to have a width corresponding to the printing width of the printing paper sheet. As an example, assuming the printing paper sheet of A4 size, the drum body 110 is formed to have a length of at least 20 to 22 cm over the whole width thereof. At this time, each ring electrode 120 may be formed to have a pitch of approximately 40 μm to achieve about five thousand lines. Also, the ring electrodes 120 are arranged in parallel with each other and formed in a ring structure which is closed as one piece or partially opened. The control unit 130 may utilize an FPCB. Also, in another exemplary embodiment of the present invention, the control unit 130 may utilize a PCB according to a designer's preference.
Referring to
Referring to
Referring to
Referring to
Referring to
A control unit guide 140 is provided in an end of the control unit 130. A conductive pattern 132 is formed in a corresponding position to each receiving groove 142 of the control unit guide 140. Also, a control section 134 may be formed to control an electrical signal in each conductive pattern 132. The control unit guide 140 is formed with receiving grooves 142 corresponding to the mold grooves 152. In this instance, by disposing the receiving grooves 142 in an identical position to the mold grooves 152 and filling a conductive material in the receiving grooves 142, the control unit guide 140 is electrically connected to the ring electrodes 134.
Referring to
Referring to
An image drum and an image drum manufacturing method according to the present exemplary embodiment utilizes a method of forming the ring electrodes 120 by filling a conductive material in the mold grooves 152 which are formed in the mold 150 and forming the ring electrodes 120 on the outer circumferential surface of the drum body 110. Namely, the ring electrodes 120 may be integrally formed with the conductive material filled into the mold grooves 152. As a result, all the minute ring electrodes 120 may be formed on the outer circumferential surface of the drum body 110 at once by injection molding. Indeed, according to the present exemplary embodiment, it is not necessary to cut each groove by using a conventional cutting tool, and the ring electrodes 120 are formed by using a molding method in the mold 150. Accordingly, the manufacturing process and cost are reduced.
Also, the control unit 130 may more precisely perform a process of controlling the ring electrodes 120 to selectively adsorb a toner so as to form an image in a printing apparatus. The drum body 110 is formed by molding, that is, by initially inserting the control unit 130 into the combination groove 162 of the core portion 160 and subsequently inserting the core portion 160 into the mold 150. Accordingly, the core portion 160 may be stably received in the drum body 110. Also, a manufacturing process may be reduced.
Referring to
A gear 212 is integrally formed in each end of the drum body 210. The gear 212 is combined with an external gear. As the external gear rotates, the gear 212 also rotates. Accordingly, a supplied toner is transferred to the image drum from a toner feed roller while moving on the circumferential surface of the toner feed roller.
Referring to
Referring to
In operation S2, a conductive material fills in the mold grooves of the mold respectively. Specifically, the conductive material fills in the hollow of the cylindrical mold by applying the conductive material. By passing a piston body having an identical diameter to an inside diameter of the hollow so as to remove the conductive material except in the mold grooves, only the conductive material remains in the mold grooves. Particularly, the diameter of the piston body should be a suitable size to appropriately fit the hollow of the cylindrical mold, so that the conductive material is only left in the mold grooves after passing through the hollow.
In operation S3, a control unit, individually applying a voltage to each terminal and using a PCB, is included and inserted into the combination groove to be partially exposed to an outside of the core portion. Additionally, a conductive pattern is formed on the control unit to be electrically connected with each ring electrode and a control section is provided in the control unit so as to transfer an electrical signal to the conductive pattern. The control unit using a PCB is fabricated into a single unit by layering a plurality of PCBs so that conductive patterns cross each other.
In operation S4, a drum body receiving the control unit is formed by initially inserting the core portion into the mold and filling a molten plastic into a space between the mold and the core portion. In this instance, the drum body is manufactured in the shape of a hollow by removing the core portion, except the control unit, from the drum body.
In operation S5, a conductive pattern is formed to be extended in a longitudinal direction of the control unit and an insulating layer is formed on a surface of the control unit. Each ring electrode contacts with only one conductive pattern.
As illustrated in
An image drum manufacturing method according to the present exemplary embodiment may integrally form the gears 212 in both ends of the drum body 210 by injection molding. Accordingly, a manufacturing process may be reduced. Also, since the control unit may utilize a PCB or an FPCB, the control unit may be integrally formed with the drum body 210, when forming the drum body 210 in the mold by injection molding.
A drum body, ring electrodes and a control unit are substantially identical to the first exemplary embodiment, and functions and effects of configuration elements are also substantially identical to the first exemplary embodiment. Therefore, the description and drawings described in the previous exemplary embodiment may be referred to, and repeated description will be omitted herein.
As described above, an image drum and an image drum manufacturing method according to the present invention form ring electrodes by filling a conductive material in mold grooves formed in the inner circumferential surface of a mold. Namely, ring electrodes are easily formed by injection molding, without cutting each groove using a conventional cutting tool. Accordingly, it is possible to reduce the manufacturing process and cost when practicing the present invention.
Also, according to the present invention, a control unit may more precisely perform a process of controlling the ring electrodes 120 to selectively adsorb toner so as to form an image in a printing apparatus. Since a drum body is fabricated through injection molding by initially coupling the control unit with a combination groove and inserting a core portion into a mold, the conventional assembling process is eliminated to reduce the manufacturing process.
Further, an image drum manufacturing method according to the present invention may integrally form gears in both ends of a drum body by injection molding. Accordingly, a manufacturing process may be reduced.
Although a few exemplary embodiments of the present invention have been shown and described, the present invention is not limited to the described embodiments. Instead, it would be appreciated by those skilled in the art that changes may be made to these exemplary embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2005-0125203 | Dec 2005 | KR | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20090215208 | Coe-Sullivan et al. | Aug 2009 | A1 |
| Number | Date | Country |
|---|---|---|
| 5-27761 | Apr 1993 | JP |
| 6-206340 | Jul 1994 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20070137776 A1 | Jun 2007 | US |
