Patent Application
20080019736
A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description of exemplary embodiments when considered in connection with the accompanying drawings, wherein:
It will be understood that if an element or layer is referred to as being “on,““against,” “connected to” or “coupled to” another element or layer, then it can be directly on, against connected or coupled to the other element or layer, or intervening elements or layers may be present.
In contrast, if an element is referred to as being “directly on”, “directly connected to” or “directly coupled to” another element or layer, then there are no intervening elements or layers present. Like numbers refer to like elements throughout.
As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures.
It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.
For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, term such as “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
Although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, it should be understood that these elements, components, regions, layers and/or sections should not be limited by these terms.
These terms are used only to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
It will be further understood that the terms “includes” and/or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
In describing exemplary embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner.
Exemplary embodiments of the present invention are now explained below with reference to the accompanying drawings.
In the later described comparative example, exemplary embodiment, and alternative example, for the sake of simplicity of drawings and descriptions, the same reference numerals will be given to constituent elements such as parts and materials having the same functions, and the descriptions thereof will be omitted unless otherwise stated.
Typically, but not necessarily, paper is the medium from which is made a sheet on which an image is to be formed. Other printable media is available in sheets and their use here is included.
For simplicity, this Detailed Description section refers to paper, sheets thereof, paper feeder, etc. It should be understood, however, that the sheets, etc., are not limited only to paper.
Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, particularly to
Referring now to
The image forming apparatus may include four image forming units 1a, 1b, 1c and 1d disposed along the traveling direction of a transfer belt 10.
The image forming unit I a may include a photoreceptor drum 2a, a drum charging unit 3a, an exposure unit 4a, a developing unit 5a, a transfer unit 6aand a cleaning unit 7a.
Similar to the image forming unit 1a, the image forming units 1b through 1d may include a photoreceptor drum, a drum charging unit, an exposure unit, a developing unit, and a cleaning unit.
The letter symbols a, b, c, and d each indicate yellow, cyan, magenta and black, respectively. For example, the image forming unit 1a forms an image of yellow, 1b forms an image of cyan, and so forth.
When the photoreceptor drum 2a receives a signal initiating an image forming operation from a controller (not shown), the photoreceptor drum 2a starts to rotate in an arrow C direction and continues to rotate until the image forming operation is completed.
When the photoreceptor drum 2a starts to rotate, a high voltage is applied to the charging unit 3a. Accordingly, a negative charge is evenly applied to the surface of the photoreceptor drum 2a.
When character data or graphic data converted to a dot image is sent as an on/off signal of the exposure unit 4a to the image forming apparatus from the controller (not shown), there is a place on the photoreceptor drum 2a where a laser beam is irradiated by the exposure unit 4a and a place where no laser beam is irradiated.
Irradiated with the laser beam from the exposure unit 4a, when the place on the photoreceptor drum 2a where the charge is reduced reaches at a position opposite to the developing unit 5a, negatively-charged toner may adhere to the place on the photoreceptor drum 2a where the charge is reduced. Accordingly, a toner image is formed.
When the toner image formed on the photoreceptor drum 2a reaches at the transfer unit 6a, due to the high-voltage applied to the transfer unit 6a, the toner image is transferred onto the transfer belt 10 traveling in an arrow A direction.
After the photoreceptor drum 2a passes the transfer position, remnants such as the toner residue on the surface of the photoreceptor drum 2 are removed by the cleaning unit 7a so that the surface is cleaned for the subsequent image forming operation.
Subsequent to the image forming operation of the image forming unit 1a, an image forming operation is performed by the image forming unit 1b in a similar manner, if not the same, as the image forming operation performed by image forming unit 1a.
Due to the high-voltage applied to the transfer unit 6b, the toner image formed on the photoreceptor drum 2b is transferred onto the transfer belt 10.
At this time, with synchronization of the timing when the image transferred on the transfer belt 10 reaches at the transfer unit 6b with the timing when the toner image formed on the photoreceptor drum 2b is transferred to the transfer belt 10, the toner images formed by the image forming units 1a and 1b are overlaid on one another on the transfer belt 10.
Similarly, toner images formed by the image forming units 1c and 1d are overlaid on one another on the transfer belt 10 so that a full color image is formed on the transfer belt 10.
Subsequently, the full color image reaches at a sheet transfer unit 9. At the same time, a sheet 8 which is transported in a direction shown by an arrow H from the sheet feed unit of the image forming apparatus (not shown) reaches at the sheet transfer unit 9.
Due to the high-voltage applied to the sheet transfer unit 9, the full color image formed on the transfer belt 10 is transferred onto the sheet 8.
Subsequently, when the sheet 8 is transported to a fixing unit 11, the toner image on the sheet 8 is heat-fixed. After the full color image passes the sheet transfer unit 9, toner which has not been transferred adheres to the transfer belt 10. The toner is removed by another cleaning unit 12.
A description will now be given of the belt traveling unit used in one such embodiment of an image forming apparatus described above.
As shown in
The transfer belt 10 is spanned, e.g., held and/or rotationally engaged, between a drive roller 18, a drift correction roller 20 and driven rollers 19a through 19d. The drive roller 18 is connected to a belt drive motor 21.
When the belt drive control unit 31 transmits a signal to control driving of the transfer belt 10, the belt drive motor 21 rotates so as to drive the transfer belt 10.
In
The position detection unit 40 may include a contact member 13 and a drift detector 15. The contact member 13 may come into contact with the belt edge. The drift detector 15 may serve as a detector for detecting the belt position.
The position detection unit 40 may detect the position of the edge of the transfer belt 10 in the width direction thereof so that an amount of drift of the transfer belt 10 in the belt width direction is detected. The detection signal of the drift detector 15 may be transmitted to the drift correction control unit 30.
The drift correction mechanism 41 may change a tilt angle of the drift correction roller 20 such that the drift of the transfer belt 10 may be corrected.
The amount of tilt of the drift correction roller 20 may be controlled based on the motor speed of a drift correction motor 22. The motor speed of the motor 22 may be determined by the drift correction control unit 30.
Referring now to
The swing arm 23 may include two swingable members 23a and 23b which are swingable in a relative direction with a rotary shaft 24 therebetween.
An end portion of the swingable member 23b may be disposed facing an end portion of the drift correction roller 20 and connected to the drift correction roller 20 in a manner such that the swingable member 23b may support a rotary shaft 20a of the drift correction roller 20. A bearing 25 may be fixed to an end portion of the swingable member 23a.
A spring 26 may be attached to the swing member 23a of the swing arm 23. By the pull tension of the spring 26, the bearing 25 is in contact with the eccentric cam 27.
The eccentric cam 27 may rotate around the rotary shaft provided at an eccentric position in an arrow D direction. The rotary shaft may be connected to the rotary shaft of the drift correction motor 22 shown in
The cam position detector 29 may be disposed in the vicinity of the eccentric cam 27. The cam position detector 29 may be structured such that the reference position of the eccentric cam 27 may be recognized when the cam position detector 29 detects the position of a shield plate 28 provided to the eccentric cam 27.
Next, a description will be given of an exemplary operation of the drift correction unit 41. The drift correction control unit 30 may instruct the motor speed of the drift correction motor 22.
When the drift correction motor 22 rotates at a predetermined angle, the eccentric cam 27 may rotate in the arrow D direction shown in
Accordingly, the bearing 25 which is in contact with the eccentric cam 27 may move up and down in an arrow E direction.
When the bearing 25 moves upward, causing one end of the swing member 23a to turn in the upward direction on the rotary shaft 24, the one end of the swing member 23b may turn in the downward direction on the rotary shaft 24.
The drift correction roller 20 is connected to the end portion of the swing member 23b. Thus, when the end portion of the swing member 23b turns downward, the drift correction roller 20 may move in a downward direction, that is, the direction shown by the arrow F in
As a result, the drift correction roller 20 with one shaft end thereof disposed at the swing member 23b may incline downward from a position L1 to a position L2.
On the contrary, when the bearing 25 moves downward, that is, in the upward direction shown by the arrow D in
In other words, because one end portion of the drift correction roller 20 may be fixed as shown in
When the drift correction roller 20 inclines, an area where friction does not evenly occur may be generated in a circumferential direction of the drift correction roller 20 around which the transfer belt 10 is spanned.
When the drift correction roller 20 moves downward, the transfer belt 10 may be dragged at an area where the friction contact is enhanced. Accordingly, the transfer belt 10 may move in the width direction in accordance with an amount of inclination of the drift correction roller 20.
Therefore, when the drift correction motor 22 controls the position of the eccentric cam 27, the tilt angle of the drift correction roller 20 may be changed so that the drift of the transfer belt 10 may be corrected.
Referring now to
In
The contact member 13 may include a spindle 14, a horizontal side 13a which may hang down from the spindle 14, a vertical side 13b attached to the spindle 14, and a regulating member 13c disposed on the horizontal side 13a of the contact member 13 facing a bottom surface of a supporting member 70.
The horizontal side 13a and the vertical side 13b are rotatively supported on the spindle 14 in directions shown by the arrows C1 and C2.
A spring 17 is attached to the horizontal side 13a of the contact member 13. The spring tension thereof exerts a force to the vertical side 13b causing the vertical side 13b to come into contact with the edge of the transfer belt 10.
When the contact member 13 moves in conjunction with a traveling motion of the transfer belt 10 in the width direction, the regulating member 13c may come into contact with the supporting member 70 which supports the drift detector 15.
Thereby, the distance between the horizontal side 13a of the contact member 13 and the drift detector 15 may be regulated.
According to the exemplary embodiment, when the distance is less than 5.0 mm, there is a possibility that the drift correction control unit 30 shown in
Therefore, the distance between the horizontal side 13a and the drift detector 15 may be configured to be no less than 5.0 mm using the regulating member 13c.
In addition, rather than integrating the regulating member 13c with the contact member 13, the regulating member 13c may individually be provided to the contact member 13.
In a case where the distance between the horizontal side 13a and the drift detector 15 is misdetected in a structure using a plurality of drift detectors 15, the regulating member 13c may be provided so that misdetection of the distance may be prevented.
Furthermore, the drift detector 15 may be provided in the proximity of the horizontal side 13a of the contact member 13 in the longitudinal direction.
The detailed description of the drift detector 15 will be omitted herein. The drift detector 15 may include a light emitting portion and a light receiving portion, for example.
The light emitted from the light emitting portion is reflected on the object to measure. The drift detector 15 may detect the distance to the object based on the position of the reflected light received by the light receiving portion and the drift of the reference position.
The contact member 13 may rotate on the spindle 14. When the distance between the drift detector 15 and the horizontal side 13a of the contact member 13 changes, an analogue signal corresponding to the changes of the distance may be obtained.
The belt drift detection principle of the drift detector 15 may include a method or device in which the drift position may be detected by detecting the position of an incident light when the contact member 13 inclines.
According to the belt traveling unit of an exemplary embodiment, the regulating member 13c may be provided. Accordingly, the distance between the drift detector 15 and the horizontal side 13a of the contact member 13 may be no less than 5.0 mm.
Thereby, when the drift detector 15 detects the belt position, misdetection may be prevented.
Thereby, it is possible to eliminate a structure to detect the drift of the contact member 13 when the contact member 13 drifts out of the detection range of the drift detector 15.
Referring now to
In the first exemplary embodiment, the distance between the drift detector 15 and the horizontal side 13a may be fixed to no less than 5.0 mm by the regulating member 13c.
In the second exemplary embodiment, a regulating member 13d may be used to adjust the distance between the drift detector 15 and the horizontal side 13a of the contact member 13 so as to be able to change the traveling amount of the contact member 13.
The regulating member 13d may be of a bolt or a screw or the like which may be adjustable. p
According to the second embodiment, the regulating member 13d may move in a direction shown by an arrow H by fastening or unfastening the regulating member 13d.
When the contact member 13 moves in conjunction with traveling of the transfer belt 10 in the width direction thereof, the distance between the drift detector 15 and the horizontal side 13a of the contact member 13 may be adjusted in accordance with the position of the regulating member 13d. Thereby, the detection range of the belt position may be adjusted.
In addition, rather than integrating the regulating member 13d with the contact member 13, the regulating member 13d may individually be provided to the contact member 13.
In a case where the distance between the horizontal side 13a of the contact member 13 and the draft detector 15 may not correctly be detected in a structure using a plurality of drift detectors 15, the regulating member 13d may be provided so that misdetection of the distance may be prevented.
Further, elements and/or features of different exemplary embodiments may be combined with each other and/or substituted for each other within the scope of this disclosure and appended claims.
Still further, any one of the above-described and other exemplary features of the present invention may be embodied in the form of an apparatus, method, system, computer program and computer program product. For example, of the aforementioned methods may be embodied in the form of a system or device, including, but not limited to, any of the structure for performing the methodology illustrated in the drawings.
One or more embodiments of the present invention may be conveniently implemented using a conventional general purpose digital computer programmed according to the teachings of the present specification, as will be apparent to those skilled in the computer art.
Appropriate software coding can readily be prepared by skilled programmers based on the teachings of the present disclosure, as will be apparent to those skilled in the software art.
One or more embodiments of the present invention may also be implemented by the preparation of application specific integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be readily apparent to those skilled in the art.
Any of the aforementioned methods may be embodied in the form of a system or device, including, but not limited to, any of the structure for performing the methodology illustrated in the drawings.
Furthermore, any of the aforementioned methods may be embodied in the form of a program. The program may be stored on a computer readable medium and is adapted to perform any one of the aforementioned methods, when run on a computer device (a device including a processor). The program may include computer executable instructions for carrying one or more of the steps above and/or one more aspects of the invention.
Thus, the storage medium or computer readable medium, is adapted to store information and is adapted to interact with a data processing facility or computer device to perform the method of any of the above mentioned embodiments.
The storage medium may be a built-in medium installed inside a computer device main body or a removable medium arranged so that it can be separated from the computer device main body. Examples of a built-in medium include, but are not limited to, rewriteable non-volatile memories, such as ROMs and flash memories, and hard disks.
Examples of a removable medium include, but are not limited to, optical storage media such as CD-ROMs and DVDs; magneto-optical storage media, such as MOs; magnetism storage media, such as floppy disks (trademark), cassette tapes, and removable hard disks; media with a built-in rewriteable non-volatile memory, such as memory cards; and media with a built-in ROM, such as ROM cassettes.
Example embodiments being thus described, it will be obvious that the same may be varied in many ways. Such exemplary variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
The number of constituent elements, locations, shapes and so forth of the constituent elements are not limited to any of the structure for performing the methodology illustrated in the drawings.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-200262 | Jul 2006 | JP | national |
