Patent Application
20130015621
Many multifunction printers, copying machines and stand-alone scanners are provided with an automatic document feeder (ADF) for automatically transporting individual sheets from a stack of media sheets to an image reading region, and then ejecting and restacking the sheets automatically onto an output tray. Maximizing the throughput performance of an ADF is important.
The drawings referred to in this description should not be understood as being drawn to scale unless specifically noted.
Reference will now be made in detail to embodiments of the present technology, examples of which are illustrated in the accompanying drawings. While the technology will be described in conjunction with various embodiment(s), it will be understood that they are not intended to limit the present technology to these embodiments. On the contrary, the present technology is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the various embodiments as defined by the appended claims.
Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present technology. However, the present technology may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present embodiments.
Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the present detailed description, discussions utilizing terms such as “sensing”, “activating”, “identifying”, “performing”, “receiving”, “communicating”, or the like, refer to the actions and processes of a computer system, or similar electronic computing device. The computer system or similar electronic computing device manipulates and transforms data represented as physical (electronic) quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission, or display devices. The present technology is also well suited to the use of other computer systems such as, for example, optical computers.
The discussion will begin with a brief overview of the operation of existing ADFs. The discussion will then focus on embodiments of the present technology that provide a system for increasing the throughput of media through an ADF. Embodiments of the present technology utilize three independent motors driving three separate gear assemblies, thereby guiding one or more media sheets through the ADF device.
In existing ADFs, an optical image reader is typically arranged at the image reading position to read (i.e. scan) the image on one side of the media sheet. Conventional ADFs have a double-sided (“duplex”) mode wherein images on both sides of a sheet are scanned by the image reader. In the double-sided mode, after the image on one side of a sheet is scanned by the image reader, the sheet is partially discharged, and then the same sheet is re-routed back through the ADF so that the image on the opposite side of the sheet can be scanned.
With reference now to
The ADF 1 includes a substantially U-shaped, main media path P1 for guiding the media sheet from the pick assembly 12 to the output tray 17. An optical window is arranged along the media path P1 between the at least one pair of opposing pre-scan rollers 14 and the at least one pair of opposing post scan rollers 15. The image data on one side of the media sheet can be read through the optical window W by a conventional image reader R, e.g. an optical scanner, which is arranged on one side the optical window W. As such, the region above the optical window W defines a first scanning region 19 of the ADF 1. The pick assembly 12 includes a pick roller 12a and a feed roller 12b, which are supported in a housing 12c. The pick assembly 12 is configured to pull (i.e., “pick”) the uppermost sheet from the media stack and transport the uppermost sheet toward the at least one pair of opposing de-skew rollers 13.
A stationary pad 11 is provided under the feed roller 12b in order to allow only the uppermost sheet to pass. Although it is not apparent from the cross-sectional view shown in
The at least one pair of opposing pre-scan rollers 14 are designed to advance the media sheet further downstream toward the first scanning region 19 where the optical window W is located. The at least one pair of opposing post-scan rollers 15 are configured to advance the media sheet from the image reading position toward the at least one pair of opposing output rollers 16. The at least on pair of opposing pre-scan rollers 14 includes a plurality of upper pre-scan rollers 14a cooperating with a plurality of lower idler rollers 14b. Similarly, the at least one pair of opposing post-scan rollers 15 includes a plurality of upper post-scan rollers 15a cooperating with a plurality of lower idler rollers 15b. The at least one pair of opposing output rollers 16 are configured to discharge to the output tray 17 the media sheet after scanning occurs. The at least one pair of opposing output rollers 16 includes a pair of upper output rollers 16a cooperating with a pair of lower output rollers 16b.
The ADF 1 also includes a switch-back path P2 that extends from the at least one pair of opposing output rollers 16 to the at least one pair of opposing de-skew rollers 13. A switching lever 18 is positioned at a junction between the main media path P1 and the switch-back path P2 to guide the direction of the sheet. The switching lever 18 is normally at a “down” position that blocks the sheet passage from the at least one pair of opposing post-scan rollers 15 to the output tray 17, unless the leading edge of a sheet being discharged pushes it upward to allow the sheet to pass. When the switching lever 18 is at the “down” position, the sheet can be guided into the switch-back path P2.
Further, with reference now to
The pick assembly 12 is coupled to a cam shaft 23 so as to be pivotable relative to the cam shaft 23. Also shown in
The media motor M1 is the power source for pivoting the pick assembly 12 downward or upward, and is also the power source for driving pre-scan rollers 14a, post-scan rollers 15a and upper output rollers 16a. The media motor M1 has a motor gear 24, which is mounted on the drive axis 25 of the media motor M1.
The pick motor M2 is the power source for driving the pick assembly 12 so as to perform picking of the uppermost sheet from the media stack. The pick motor M2 is also the power source for driving the lower de-skew rollers 13b in order to advance the media sheet toward the pre-scan rollers 14.
The solenoid SOL is operatively connected to the lower output rollers 16b such that the lower output rollers 16b are caused to move toward from the upper output rollers 16a when the solenoid SOL is activated at a predetermined timing. As such, the timing for nipping the upper and lower output rollers (16a, 16b) can be controlled by the solenoid SOL.
Instead of using solenoids and a pick motor that drive deskew rollers, embodiments of the present technology utilize three independently operating motors to drive corresponding assemblies at independent rates, thereby increasing the throughput of media sheets by an automatic document feeder. More specifically, embodiments of the present technology include a pick, feed and deskew motor as well as a sensor assembly. The pick motor drives the pick assembly to pull a media sheet from a media stack and feed it into a main media pathway through the ADF. The sensor assembly includes a plurality of sensors that are coupled with a computer and at least one of the pick assembly, the deskew assembly, the feed assembly and the first scanner. In general, the sensor assembly senses the media sheet's presence at a predetermined location near each motor and scanner and then sends at least one signal to the computer (as will be described herein). Based on the at least one signal sent to the computer, the computer sends an activation signal to at least one of the motors and scanners, causing the motors to drive associated assemblies and alerting the scanners that a media sheet will arrive shortly and to prepare themselves for scanning.
For example, but not limited to, in one embodiment, the computer sends a signal to the deskew motor, alerting the deskew motor to begin operating because the media sheet is approaching along the main media path. The deskew motor then begins operating, driving the deskew assembly. The deskew assembly consequently deskews the media sheet and moves it from the pick assembly to the feed assembly. Ultimately, the feed motor subsequently drives the feed assembly to feed the media sheet towards a scanning region along the main media path.
Further, embodiments of the present technology enable additional components to be easily added to the ADF, the components of which also serve to further increase the ADF's efficiency. For example, but not limited to, a second scanner may be added along the main media pathway so that both sides of a media sheet may be scanned. Thus, the media sheet need only make one pass (instead of three) through the ADF before it reaches the output tray.
Thus, by enabling the pick, deskew and feed assemblies (as well as the pick, deskew and feed motors) to operate independently of each other and in parallel with each other, as well as at different rates, embodiments of the present technology provide for more efficient pulling (picking), deskewing, feeding and scanning of media sheets, thereby saving time and thus resources. Moreover, since the pick, deskew and feed motors are direct current operating motors, they are quieter than the stepper motor and solenoid of conventional ADFs.
The following discussion will begin with a description of the structure of the components of the present technology. The discussion will then be followed by a description of the components in operation.
Further,
Embodiments of the present technology include a pick motor 305, a feed motor 315, a sensor assembly 320 and a deskew motor 310. In one embodiment, the pick motor 305 is coupled with a pick assembly 12. The pick assembly 12 includes a first and second pick roller, 12a and 12b, respectively. The pick motor 305 drives the pick assembly 12, whereas the pick assembly 12 pulls a media sheet from a media stack one by one and feeds the media sheet into a main media path P1. The main media path P1 guides the media sheet from the pick assembly to a first scanning region 19 and from the first scanning region 19, ultimately to an output tray 17. The first scanning region 19 is coupled with a first scanner 405 positioned for scanning an image of a first side of the media sheet as it passes through the first scanning region 19. While described later, the first scanning region 19 is that region within which a media sheet is scanned. Of note, the first scanner 405 of
In one embodiment, the pick assembly 12 includes a stationary pad 11 configured for ensuring that more than one media sheet does not enter the main media path P1 at the same time. The stationary pad 11 further increases the ADF's ability to reduce hand-off error occurring from the release of the pick assembly 12.
In one embodiment, the deskew motor 310 is coupled with a deskew assembly. The deskew motor 310 drives the deskew assembly. It should be appreciated that the deskew assembly includes the at least one pair of opposing deskew rollers 13. The deskew assembly deskews the media sheet and moves the media sheet from the pick assembly 12 to the feed assembly 425. For example, the deskew assembly squares the leading edge of a media sheet. The squared media sheet is then delivered to the feed assembly 425 (e.g., the at least one pair of opposing pre-scan rollers 14, as will be described). The deskew assembly moves independently of the pick assembly and the feed assembly 425.
In another embodiment, the feed motor 315 is coupled with the feed assembly 425. The feed motor 315 drives the feed assembly 425. The feed assembly 425 feeds the media sheet towards the first scanning region 19 along the main media path P1.
The feed assembly 425, in one embodiment, includes at least one pair of opposing pre-scan rollers 14, at least one pair of opposing post-scan rollers 15 and at least one pair of opposing output rollers 16 and a switch-back path P2.
The at least one pair of opposing pre-scan rollers 14 are positioned along the main media path P1 after the deskew assembly and before the first scanning region 19. The at least one pair of opposing post-scan rollers 15 are positioned along the main media path P1 after the first scanning region 19. Further, the at least one pair of opposing output rollers 16 are positioned along the main media path P1 after the at least one pair of opposing post-scan rollers 15 and before the output tray 17. In one embodiment, the at least one pair of opposing pre-scan 14, post-scan 15 and output rollers 16 are configured for advancing the media sheet in a forward direction toward the output tray 17 while the first side of the media sheet is scanned during a first pass of the first scanner 405. In another embodiment, the at least one pair of opposing pre-scan 14, post-scan 15 and output rollers 16 are configured for advancing the media sheet in a reverse direction away from the output tray 17, after the first side of the media sheet is scanned during the first pass under the first scanner 405.
The switch-back path P2 extends from the at least one pair of output rollers 16 toward the deskew assembly. The switch-back path P2 receives the media sheet driven in reverse by the at least one pair of opposing output rollers 16 such that the media sheet is then turned around. The media sheet is further driven in reverse, away from the output tray 17 and towards the at least one pair of opposing pre-scan rollers 14. The second side of the media sheet that is driven in such reverse direction, is then able to be scanned in a second pass through the first scanning region 19. Whereupon, after this second pass through the first scanning region 19 while moving towards the at least one pair of opposing pre-scan rollers 14, the media sheet is once again advancing in a forward direction toward the output tray 17, for a “third pass”.
During this third pass, the media sheet once again travels past the post-scan rollers along the main media path P1, and then travels along the switch back path P2, to turn around once again. This second “turn around” of the media sheet is necessary in order that the media sheet remains in the same orientation and placement as its position within the original media stack before the media sheet was fed into the ADF for copying. Of note, in one embodiment, during the third pass, since the media sheet is not being scanned, the media sheet is not deskewed. Thus, in one embodiment, during the third pass, the deskewing function, that of squaring (or in this case re-squaring) the leading edge of the media sheet does not occur. In other words, during the third pass, the deskewing function becomes dormant for the entirety of just the third pass. The media sheet merely passes through the deskew assembly and the feed assembly 425 towards the output tray 17. In fact, the computer 500 may optionally send a signal to individual motors or a signal to the collective group of motors to change their speed at which the individual motors are operating. For example, the signal may direct the individual motors to speed up their functioning during the third pass. In this regards, the travel time of the media sheet through the ADF machine then would be less during the third pass compared to the first and/or the second pass.
Significantly, in embodiments of the present technology, the pick motor 305 moves independently of the deskew 310 and feed motors 315. Due to the number of independent motors in embodiments of the present technology, the inter-page gap between being picked and being fed to the scanning region 19 is reduced. In other words, the deskew motor 310 picks up the slack occurring between the driven pick assembly 12 and the driven feed assembly 425, by driving the media sheet along the main media path P1 at an accelerated rate, thereby reducing the time gap occurring between media sheets being scanned.
For example, and as explained herein, during the third pass of a media sheet in a three pass single scanner system, the assemblies may be driven faster by the motors. Additionally, during the third pass, the pick motor 305 may drive the pick assembly 12 to pick up a media sheet, in anticipation of running it along the main media path P1. Once picked, the media sheet is then “parked” (not moving) in the pick assembly 12, waiting for the pick motor 305 to begin operation again, wherein the pick motor 305 drives the pick assembly 12 to cause the media sheet to move along the main media path P1. In another embodiment, the “pick and park” function occurs during a first and/or second pass of the media sheet moving along the main media path P1.
Thus, due to independently operating motors and assemblies enabling parallel operation and movement of more than one media sheet along the main media path P1, its “pick and park” ability, as well as the computer 500′s ability to determine the location and speed of moving media sheets along the main media path P1, embodiments of the present technology enable a media sheet to move through the ADF machine at a faster rate than conventional ADF machines, thereby increasing throughput. Moreover, due to the deskew assembly, the greater throughput is also of greater quality than that of conventional ADF machines. Furthermore, it should also be appreciated that due to the independently operating motors, not only can the motors be sped up during one of the three passes, but the motors may operate such that they drive the associated assemblies at different speeds, in contrast to the conventional ADFs in which all assemblies operate at the same speed. Thus, embodiments of the present technology with independently operating assemblies activated by the computer 500 (which gathers signals from the sensor assembly 320) provide for more optimization design choices.
In one embodiment, the sensor assembly 320 is coupled with the main media path P1. The sensor assembly 320 includes a plurality of sensors. Each sensor of the plurality of sensors is coupled with at least one of the pick assembly 12, the deskew assembly, the feed assembly 425, the first scanner 405 and the second scanner 450 (as will be discussed later and is shown in
Thus, as explained herein, since the various motors are able to operate independently, the associated assemblies also are able to operate independently. Therefore, the various assemblies are able to speed up and slow down the movement of a media sheet along the main media path P1, in order to at least either reduce the inter-page gap or increase the speed of the media sheet during certain passes (e.g., third pass). Further, and significantly, the ability of the pick assembly 12 (and more particularly, the first pick roller 12a) to pick and/or attempt to pick a media sheet from the media stack and then wait with that media sheet until the media sheet may be fed further along the main media path P1 is important. In many cases, it takes several tries to “pick” just one media sheet. Since, the pick assembly 12 attempts to pick (and in many cases successfully picks) a next media sheet during the same time that the rest of the ADF is busy moving the previously picked media sheet along the main media path P1, when the ADF system is ready to move the next media sheet, it is already poised and ready to be moved, thus saving pick time. Consequently, embodiments of the present technology enable a more efficient ADF system with greater throughput than conventional ADFs.
It is significant to note that since the computer 500 receives the signals from all of the sensors of the sensor assembly 320, the computer 500 is able to track the media sheets as they move along the main media path P1. The computer 500 is able to make intelligent decisions as to when, where, and how fast a media sheet should move along the main media path P1, based on the information received from the sensors of the sensor assembly 320.
Referring specifically to
The paper presence sensor 410, the pick success sensor 415, the deskew sensor 420 and the pre-scan sensor 425 comprise the sensor assembly 320, according to one embodiment of the present technology. It should be appreciated that the sensor assembly 320 may have more or less sensors than the ones noted herein.
In one embodiment, the paper presence sensor 410 and the pick success sensor 415 are coupled with the pick assembly 12 and the computer 500. The deskew sensor 420 is coupled with the deskew assembly and the computer 500. The pre-scan sensor 425 is coupled with the feed assembly 425 and the computer 500. Each sensor of the sensor assembly 320 alerts the computer 500 that the media sheet moving along the main media path P1 is within a predetermined distance from the assemblies associated with the motor.
For example, but not limited to, once the media sheet within a media stack is determined to be “present” by being positioned at a predetermined location along the main media path P1, the paper presence sensor 410 sends a signal to the computer 500. The signal signifies to the computer 500 that the media sheet is at a predetermined distance away from/ to the first and second pick rollers 12a and 12b, respectively of the pick assembly 12. The computer 500, based on this information and information from other sensors, sends an activation signal to the pick motor 305, signifying that it should begin the operation of picking up a media sheet. Once operation has begun, the pick motor 305 drives the pick assembly 12, and thereby the first and second pick rollers 12a and 12b, respectively, to pick the media sheet from the media stack and cause it to travel along the main media path P1 towards the deskew assembly. Further, the activation signal sent to the pick motor 305 also includes a direction regarding the speed at which the pick motor 305 should operate.
Further, in one embodiment, the pick success sensor 415 sends a signal to the computer 500 when it is determined that a media sheet has passed the second pick roller 12b. The computer 500, based on the signal sent to the computer 500 by the pick success sensor 415 and other information sent from other sensors, sends an activation signal to the deskew motor 310, causing the deskew motor 310 to begin driving the at least one pair of opposing deskew rollers 13 of the deskew assembly to perform deskewing, described herein. The pick success sensor 415 may also send a signal to the computer 500 if it is determined that a media sheet has not passed the second pick roller 12b. In another embodiment, the pick success sensor 415 does not send a signal, regardless of determining that a media sheet has not passed the second pick roller 12b.
In the case in which a media sheet is detected by the pick success sensor 415 to have passed the second pick roller 12b, the computer 500 will determine the distance from the leading edge of the media sheet to the at least one pair of opposing deskew rollers 13 depending on the pick and scan speed determined and send the signal to activate the deskew algorithm for the at least one pair of opposing deskew rollers 13 and first and second pick rollers, 12a and 12b, respectively, to be driven.
In one embodiment, in the case in which the media sheet is not detected by the pick success sensor 415, then the computer 500 sends a signal to the pick rollers to do a pick re-try algorithm for two more times. During these re-tries, the pick assembly 12 will move up and down trying to move the top media sheet to pass the pick success sensor 415. After these two re-tries, if it still does not detect a media sheet having passed the second pick roller 12b, then the computer 500 sends the signal to all the motors to cease operation and sends the signal to the user interface (control panel) to request a re-stacking of the input stack. It should be appreciated that while in one embodiment, two re-tries are attempted, other embodiments may include more or less re-try attempts.
In one embodiment, the computer 500 sends signals to the pick motor 305, deskew motor 310 and the feed motor 315 for cessation of operations in the situation in which a media sheet is not detected and two re-tries have been attempted and failed, as described above.
In one embodiment, the deskew sensor 420 sends a signal to the computer 500 when the deskew sensor 420 determines that the media sheet moving along the main media path P1 reaches a predetermined location or a predetermined distance away from the deskew sensor 420, the at least one pair of opposing deskew rollers 13, or both. It should be noted that, as will be described herein, the deskew motor 310 is associated with at least three functions: 1) deskewing the media sheet; 2) driving the deskew assembly to activate the first (or second 530) selectable background assembly 525; and 3) opening and closing (nipping) the at least one pair of opposing output rollers 16. However, it should be appreciated that the opening and closing of the opposing output rollers 16 is a non-dedicated function. In other words, the nipping may be performed by a free motor (a motor operating independently of another motor). Thus, in one embodiment, the opening and closing of the at least one pair of opposing output rollers 16 is driven by the pick motor 305, instead of the deskew motor 310.
In one embodiment, the pre-scan sensor 425 sends a signal to the computer 500 when the pre-scan sensor 425 determines that the media sheet moving along the main media path P1 reaches a predetermined location or a predetermined distance away from the pre-scan sensor 425, the at least one pair of opposing pre-scan rollers 14, or both. As stated herein, the feed assembly 425 includes the at least one pair of opposing pre-scan rollers 14, the at least one pair of opposing post-scan rollers 15 and the at least one pair of opposing output rollers 16. The rollers 14, 15 and 16 of the feed assembly operate in tandem and at the same speed, with the same timing. The computer 500, based on the signal sent from the pre-scan sensor 425 and other information sent from other sensors, sends an activation signal to the feed assembly 425 to begin operating, at a certain speed.
Thus, once the media sheet is fed through the at least one pair of opposing pre-scan rollers 14, it continues to move along the main media path P1, over the first scanner 405 within the first scanning region 19, and through the at least one pair of opposing post-scan rollers 15 towards the output tray 17.
However, once the media sheet moves past the at least one pair of opposing post-scan rollers 15, and a portion of the media sheet moves through the at least one pair of the opposing output rollers 16, the feed motor 315 reverses itself, thus reversing the direction of the rollers of the feed assembly. More particularly, the rollers of the feed assembly 425 reverse when the trailing edge of the media sheet comes near to going through the at least one pair of the opposing output rollers 16. Further and of note, the pre-scan sensor 425 coupled with the feed assembly 425 and the computer 500, is able to determine the position of the trailing edge of the media page during its movement along the main media path P1, through the different opposing rollers of the feed assembly 425. Once the pre-scan sensor 425 senses that the trailing edge of the media sheet reaches a predetermined location near the at least one pair of opposing output rollers 16, the computer 500, having received these signals regarding the position of the media sheet from the pre-scan sensor 425, sends an activation signal to the feed motor 315, thereby causing the operation of the feed assembly 425 to be reversed.
Once the feed assembly 425, and hence the feed rollers reverse themselves, the media sheet follows the switch-back path P2 towards the at least one pair of opposing deskew rollers 13, as well as the deskew sensor 415. The deskew sensor 420 senses the presence of the media sheet at a predetermined location, such as buckling at the entrance to the main media path P1 between the at least one pair of opposing deskew rollers 13, and sends a signal to the deskew motor 310 that the deskew motor 310 should resume operation, thereby driving the at least one pair of opposing deskew rollers 13 to pull the media sheet into the main media path P1. The media sheet then continues its movement along the main media path P1 as has been described herein.
Significantly, it can be seen that once the media sheet passes through the at least one pair of opposing post-scan rollers 15, partially enters the at least one pair of opposing output rollers 16, moves backwards along the switch-back path P2, enters the main media path P1 through the at least one pair of opposing deskew rollers 13, and continues along the main media path P1 to then be scanned for a second time by the first scanner 405, the media sheet itself has been turned around such that the other side of the media sheet is the side that is being scanned during the second scan. Of further note, if the media sheet were then to exit the main media path into the output tray 17 at this stage, the resulting media stack would result in media sheets arranged in an order different from that order of the media stack before it entered the ADF.
Furthermore, on the media sheet's second and third pass (described below), the deskew motor 310 drives the at least one pair of opposing output rollers 16 to open and close (nip) very quickly, such that the leading edge and the trailing edge may cross each other. In one embodiment, after the at least one pair of opposing output rollers 16 nip shut, the components of the feedback assembly 425, including the at least one pair of opposing output rollers 16, continue to operate in the forward direction for a short period of time, and then change to operate in the reverse direction, thus moving the media sheet towards the switch-back path P2. However, in another embodiment, after the at least one pair of opposing output rollers 16 nip shut, the components of the feedback assembly 425, including the at least one pair of opposing output rollers 16, continue to operate in the forward direction, and move the media sheet towards the output tray 17.
Moreover, the pre-scan sensor 425 sends a signal to the computer 500 regarding the position of the media sheet along the main media path P1 and within the feed assembly 425 area. Based on this signal from the pre-scan sensor 425 and other signals from sensors within the sensor assembly 320, the computer 500 sends an activation signal to the feed assembly 425, and more particularly, to the at least one pair of opposing output rollers 16, to open up (allowing the trailing edge and the leading edge of the media sheet to cross each other) and then close again. This nipping, driven by, in one embodiment, the deskew motor 310, occurs in only the second and third pass of the three pass single scanner system 400B.
Thus, instead of using a solenoid to drive the nipping of the at least one pair of opposing output rollers 16, embodiments of the present technology utilize an independently operating motor, such as but not limited to, the deskew motor 310, to drive the nipping of the at least one pair of opposing output rollers 16. Additionally, since the nipping of the at least one pair of opposing output rollers 16 is a non-dedicated function, the determination of which motor of an ADF 300 is to include the function of nipping may be decided based on optimizing the objectives for the ADF 300 itself. For example but not limited to such, it may be determined that the deskew motor 310 should be designed to drive the nipping of the at least one pair of opposing output rollers 16, based on, perhaps, a large number of functions already assigned to the deskew motor 310.
Consequently, in regards to the second and third pass, the media sheet moves along the main media path P1 and the switch-back path P2 once more, for a third pass, before the media sheet is released to the output tray 17 to form a resulting media stack. During this third pass, in one embodiment, the operation of the sensor assembly 320 along with the pick motor 305, deskew motor 310 and feed motor 315 and their associated assemblies, is the same as that operation during the second pass. However, in another embodiment, the operation of the sensor assembly 320 along with the pick motor 305, deskew motor 310 and feed motor 315 and their associated assemblies, is different as that operation during the second pass.
For example, and as explained herein, during the third pass, the pick motor 305, the deskew motor 310 and the feed motor 315 may be instructed, through the activation signal, to speed up. This is because it is not necessary that the media sheet be deskewed since the media sheet will not be “scanned” during the third pass. Thus, the movement of the media sheet through the main media path P1 during the third pass may be significantly faster than that movement during the first and the second pass.
As stated herein, the pick motor 305, the deskew motor 310 and the feed motor 315 operate independently, and are capable of operating at different speeds and at different times. The sensors of the sensor assembly 320 are able to sense when the media sheet is approaching its associated rollers and signal to the computer 500, which then activates various motors to begin driving the associated assemblies that move the media sheet along the main media path P1. Further, in one embodiment, since the sensors of the sensor assembly 320 are able to communicate with each other, the sensors are thus able to anticipate when a media sheet is moving near and/or moving into the output tray 17, and to ready its associated assemblies with a second media sheet. Therefore, embodiments of the present technology enable a greater throughput to be realized.
As can be seen, the single pass two sided scan system 400C of
In one embodiment, the ultrasonic multi-feed sensor 440 senses when more than one media sheet is picked by the pick assembly 12, and sends a signal to the computer 500 of such. The computer 500, based on the signal from the ultrasonic multi-feed sensor 440 as well as signals from other sensors, sends an activation signal to the pick motor 305, the deskew motor 310 and the feed motor 315 to cease operations until the main media path P1 is cleared of the multiple media sheets picked at the same time by the pick assembly 12. The ultrasonic multi-feed sensor 440 also functions to help the computer 500 determine at what speed the motors should be operating, thereby driving the assemblies which move the media sheet along the main media path P1. For example, the ultrasonic multi-feed sensor 440 is able to detect how thick a piece of media sheet is by causing an ultrasonic waveform to be directed at the media sheet Based on this thickness information sent to the computer 500, the computer 500 is able to calculate how fast and/or how close the trailing edge of the media sheet should be approaching the deskew assembly. For example, a thick piece of media sheet will not buckle very much at the at least one pair of opposing deskew rollers 14a. Therefore, the computer 500, based on the thickness information, will determine the speed at which the media sheet should approach the deskew assembly, and how close portions of the media sheet to get to the deskew assembly before the deskew motor begins operations.
In one embodiment, after the media sheet passes through the at least one pair of opposing post-scan rollers 15, it then moves forward along the main media path P1 towards the second scanner 450 coupled with a second scanning region 455. Further, in one embodiment, the second pre-scan sensor 445 senses when the media sheet is a certain distance away from itself and/or the second scanner 450. Upon sensing the media sheet at a predetermined distance away, the second pre-scan sensor 445 sends a signal to the computer 500. The computer 500 then sends an activation signal to the second scanner 450, alerting the second scanner 450 that a media sheet is arriving forthwith. Of note, the second scanner 450 resides within the ADF 300. Further, the second scanner 450 is positioned so that the side opposite the side that was scanned by the first scanner 405 is then scanned.
In one embodiment, the scanning region 19 of the ADF device includes a second scanner 410 positioned for scanning an image of a second side of a media sheet such that the first and the second sides of the media sheet are scanned in a single pass through the scanning region 19 before the media sheet is output to the output tray 17.
Thus, embodiments of the present technology also enable components to be added in order to arrive at either a three pass single scanner system 400B or a single pass two sided scan system 400C. Embodiments of the present technology provide for independently operating motors that are able to run at different speeds and times and that are able to monitor the movement of media sheets through the ADF. Thus, for example, if the sensor assembly 320 determines that a media sheet has moved through the main media path P1 such that a large gap is left between the first media sheet and the second media sheet moving along the main media path P1, then the sensor assembly 320 may signal to the computer 500, which in turn activates the appropriate motor to begin/change its operating speed. In one embodiment, the appropriate motor drives its associated assembly at a faster rate in order to catch the second media sheet up with the first, thereby closing the inter-page gap and increasing throughput.
Referring now to
In one embodiment, the first selectable background assembly 525 faces a second side of the media sheet as it passes through said first scanning region 19. The second side is opposite said first side of the media sheet. The first selectable background assembly 525 responds to the selectable background selection by toggling to a position corresponding to a black or white background of the selectable background selection.
In another embodiment, a second selectable background assembly 530 is coupled with the computer 500, as well as the first selectable background assembly 525. The second selectable background assembly 530 faces the first side of the media sheet as it passes through the second scanning region 455. The second selectable background assembly 530 responds to the selectable background selection by toggling to a position corresponding to a black or white background of the selectable background selection.
The first and second selectable background assembly, 525 and 530, respectively, prevent light from leaking through paper, from the front to back or vice versa, thereby causing the back side image of a scanned document from undesirably showing up in the copied image. Most ADF machines use a white background when scanning images. In anticipation of an image “leaking” through a document during scanning, a user may select a black background. The black background prevents the text on the back side of a media sheet from reflecting back to the front side. Thus, the scanner is prevented from seeing the back side of the media sheet.
Once the black background is selected, the computer 500 sends a signal to the deskew motor 310. The deskew motor 310 drives the deskew assembly to activate the first (or second 530) selectable background assembly 525. The first selectable background assembly 525 (or the second selectable background assembly 530) then toggles (e.g., rocks back and forth) to the position such that a black background is provided. This can be seen in
Significantly, the first and second selectable background assemblies, 525 and 530, respectively, are coupled with each other. When the first selectable background assembly 525 is in a position providing for a black background, so is the second selectable background assembly 530 in a position providing for a black background. Additionally, the three pass single scanner system 400B only may accommodate a first selectable background assembly 525. However, the single pass two sided scan system 400C may accommodate both a first and second selectable background assembly, 525 and 530, respectively.
Further, only the single pass two sided scanner system 400C has a calibration mode. More particularly, the second scanner 450 has a calibration strip. The second selectable background assembly 530, upon demand (e.g., a receipt of a selection of a white or black background) moves to the calibration strip position so that one or more sensors within the second scanner 450 can calibrate themselves. After the one or more sensors within the second scanner 450 calibrate themselves, the second selectable background assembly 530 toggles to the selected background position. Thus, if a white background has been selected, then the second selectable background assembly 530 toggles to a position that would produce a white background. If a black background has been selected, then the second selectable background assembly 530 toggles to a position that would produce a black background. Significantly, since the second selectable background assembly 530 is only activated on-demand and does not continuously move to a calibration position, the second selectable background assembly 530 is able to avoid inadvertent or unnecessary scratching and contamination as a media sheet passes through the second scanning region 455.
In one embodiment, and of further note, one or more sensors within the first scanner 405 are able to move to a predetermined position and do sensor calibration, such that the one or more sensors do not need to use the first selectable background assembly 525 for calibration, even though the first selectable background assembly 525 could be used for this purpose.
Thus, embodiments of the present technology enable the addition of components to achieve a three pass single scanner system 400B or a single pass two sided scanner system 400C. The independently operated pick motor 305, deskew motor 310 and feed motor 315 enable both the three pass single scanner system 400B and the two sided scanner system 400C to achieve a greater throughput than conventional ADFs, with better quality copies.
Referring now to
Significantly and as will be explained below, embodiments of the present technology enable the operation of an ADF utilizing a three pass single scanner system and a single pass two sided scan system.
At 602 of
At 604 of
For example, and referring to 606 of
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At 609 of
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At 614 of
Further, in one embodiment and as already described herein, the media sheet is then received along the switch-back path P2, while the at least one pair of opposing output rollers 16 operate in reverse. The switch-back path P2 extends from the at least one pair of opposing output rollers 16 toward the deskew assembly.
Additionally, in one embodiment and as already described herein, the media sheet is advanced towards the first scanning region 19 after the media sheet moves from the switch-back path P2 into the main media path P1 such that a second side of the media sheet is scanned in a second pass through the first scanning region 19. Moreover, in one embodiment and as already described herein, after the second side of the media sheet is scanned in the second pass, the media sheet is advanced in a forward direction toward the at least one pair of opposing output rollers 16. Whereupon, once arriving at the at least one pair of opposing output rollers 16, the media sheet is advanced towards the switch-back path P2 for a third pass along the main media path P1, wherein the at least one pair of opposing output rollers 16 are operating in reverse. The third pass turns the media sheet around, thus enabling the media sheet to arrive at the output tray 17 in a same order as that order input form the media stack into the main media path P1.
It should be appreciated that the activation signal sent by the computer 500 to a motor to drive the opening and the closing of the at least one pair of output rollers 16 is dependent upon at least, but not limited to, the length of the media sheet itself as it passes through the feed assembly 425 rollers, the stage within the operation of the ADF 300 (e.g., the first, second or third pass) and the location of the media sheet as determined by the pre-scan sensor 425. For example, during the second and third pass of the media sheet along the main media path P1, in one embodiment, the deskew motor 310 drives the at least one pair of opposing output rollers 16 to open and close (nipping) such that the leading and trailing edge of the media sheet may cross each other.
In another example, if the length of a media sheet moving along the main media path P1 is more than 11 inches, then the at least one pair of opposing output rollers 16 open up. However, if the length of the media sheet is less than 11 inches, then the at least one pair of opposing output rollers 16 do not open. In one embodiment, such as during the second pass, after the at least one pair of opposing output rollers 16 close, the rollers of the feed assembly 425 moves in the forward direction (moving the media sheet along the main media path P1 towards the output tray 17) and then moves in the reverse direction (moving the media sheet along the switch-back path P2 towards the deskew assembly), per the instructions from the computer 500. In another embodiment, such as at the end of the third pass, after the at least one pair of opposing output rollers 16 close, the rollers of the fee assembly 425 continue to move in the forward direction (moving the media sheet along the main media path P1 towards the output tray 17). It should be appreciated that while in one embodiment, the deskew motor 310 drives the nipping of the at least one pair of opposing output rollers 16, in another embodiment, another motor (e.g., pick motor 305) drives the nipping of the at least one pair of opposing output rollers 16.
In another embodiment and as described herein, the feeding of 614 includes advancing the media sheet in a forward direction through the first scanning region 19 and towards a second scanner 450 of a second scanning region 455. The second scanning region 455 is positioned between opposing post-scan rollers 15 and opposing output rollers 16. The second scanner 450 is positioned for scanning an image of a second side of the media sheet such that the first and second sides of the media sheet are scanned in a single pass through the first and second scanning regions, 9 and 455, respectively, before the media sheet is output to the output tray 17. In one embodiment, the advancing is performed by at least one pair of opposing pre-scan rollers 14, at least one pair of opposing post-scan rollers 15. The at least one pair of opposing pre-scan rollers 14 are positioned along the main media path P1 after the deskew assembly and before the first scanning region 19. The at least one pair of opposing post-scan rollers 15 are positioned along the main media path P1 after the first scanning region 19. The at least one pair of opposing output rollers 16 are positioned along the main media path P1 after the at least one pair of opposing post-scan rollers 15 and before the output tray 17.
At 616 of
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In one embodiment, the picking 602 and deskewing 610 occur at speeds less than a speed of the feeding 614.
Embodiments of the present technology, with some simple modifications of the base ADF, work with both three pass single scanner systems and single pass two sided scan systems. The three pass single scanner system is one in which there is just a single scanner. The media sheet must move in a first direction to allow the single scanner to scan one side of the media sheet. The media sheet is fed through a switch-back path P2 such that the media sheet is turned around. Then, the media sheet makes a second pass through the scanning region 19, allowing the other side of the media sheet to be scanned. The media sheet must then make a third pass (to turn the media sheet around again) through the switch-back path P2, the at least one pair of opposing deskew, pre-scan and post-scan rollers, 13, 14 and 15, respectively, before the media sheet is guided to the output tray 17 by the feed assembly 425.
The single pass two sided scan system, on the other hand, includes two scanners, one within the first scanning region 19 and one within the second scanning region 455, one on either side of the passing media sheet. Thus, the media sheet only passes through each of the first and second scanning regions, 19 and 455, respectively, once, and remains moving in one direction along the main media path P1.
Thus, embodiments of the present technology enable more throughput through an ADF by providing a system including independent motors operating at different speeds, thereby reducing the inter-page gap during the scanning process. Further, embodiments of the present technology enable the better identification of the edges of the media sheets and the switching of black and white selectable backgrounds, thereby facilitating a better quality copy. Moreover, embodiments of the present technology work with both a three pass single scanner system and a single pass two sided scan system, thereby providing quality choices for consumers.
With reference now to
System 700 of
System 700 also includes computer usable non-volatile memory 710, e.g. read only memory (ROM), coupled to bus 704 for storing static information and instructions for processors 706A, 7068, and 706C. Also present in system 700 is a data storage unit 712 (e.g., a magnetic or optical disk and disk drive) coupled to bus 704 for storing information and instructions. System 700 also includes an optional alphanumeric input device 714 including alphanumeric and function keys coupled to bus 704 for communicating information and command selections to processor 706A or processors 706A, 706B, and 706C. System 700 also includes an optional cursor control device 716 coupled to bus 704 for communicating user input information and command selections to processor 706A or processors 706A, 706B, and 706C. System 700 of the present embodiment also includes an optional display device 718 coupled to bus 704 for displaying information.
Referring still to
System 700 is also well suited to having a cursor directed by other means such as, for example, voice commands. System 700 also includes an I/O device 720 for coupling system 700 with external entities. For example, in one embodiment, I/O device 720 is a modem for enabling wired or wireless communications between system 700 and an external network such as, but not limited to, the Internet. A more detailed discussion of the present technology is found below.
Referring still to
The computing system 700 is only one example of a suitable computing environment and is not intended to suggest any limitation as to the scope of use or functionality of the present technology. Neither should the computing environment 700 be interpreted as having any dependency or requirement relating to any one or combination of components illustrated in the example computing system 700.
The present technology may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. The present technology may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer-storage media including memory-storage devices.
All statements herein reciting principles, aspects, and embodiments of the invention as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. The scope of the present invention, therefore, is not intended to be limited to the exemplary embodiments shown and described herein. Rather, the scope and spirit of present invention is embodied by the appended claims.
