The present disclosure relates to a recording apparatus capable of performing double-sided recording on sheets.
Japanese Patent Application Laid-Open No. 2014-043338 discusses a recording apparatus that records images on both sides of a sheet by reversing a traveling direction of the sheet in a reverse path after a transfer unit transfers the image to one side of the sheet. In a case where a plurality of sheets is conveyed from the reverse path to the transfer unit, the recording apparatus can convey the preceding sheet and the subsequent sheet fed following the preceding sheet in opposite directions in the reverse path so that the preceding sheet and the subsequent sheet pass by each other. This makes it possible to perform double-sided recording on the plurality of sheets continuously and efficiently without increasing a conveyance path.
In the recording apparatus discussed in Japanese Patent Application Laid-Open No. 2014-043338, the preceding sheet and the subsequent sheet, which are away from each other in the conveyance direction, pass by each other in the reverse path. Thus, it takes time to convey the sheets through the reverse path, and this may lead to a decrease in productivity.
The present disclosure is directed to a recording apparatus that improves productivity in double-sided recording on a plurality of sheets.
According to an aspect of the present disclosure, a recording apparatus includes a feed roller configured to feed a sheet, a conveyance roller configured to convey the sheet fed by the feed roller, a recording unit configured to perform recording on the sheet conveyed by the conveyance roller, a reverse path configured to reverse, in the reverse path, a traveling direction of the sheet on which the recording is performed by the recording unit, and a control unit configured to perform control so that a leading edge of a second sheet overlaps a first sheet on which recording is being performed by the recording unit, wherein recording on the second sheet is to be performed by the recording unit following the recording on the first sheet, and wherein the control unit performs control to reverse the traveling direction of the first sheet and the traveling direction of the second sheet in the reverse path while maintaining an overlapping state of the first sheet and the second sheet.
Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
An exemplary embodiment of the present disclosure will be described below with reference to the drawings. Dimensions, materials, shapes, and relative arrangements of components according to the exemplary embodiment described below can be changed as appropriate based on a configuration of an apparatus to which the exemplary embodiment is applied or based on various conditions and are not intended to limit the scope of the present disclosure to the exemplary embodiment described below.
A recording apparatus 200 according to an exemplary embodiment of the present disclosure will be described below with reference to
The recording apparatus 200 uses a serial-type inkjet method of recording images on sheets P by ejecting ink supplied from an ink tank 30 onto the sheets P. The present exemplary embodiment is also applicable to line head-type inkjet recording apparatuses and electrophotographic recording apparatuses. The term “recording” encompasses not only cases of forming meaningful information, such as text and graphics, but also cases of forming images, designs, and patterns on wide areas of the sheets P. While the sheets P are assumed to be sheets of paper in the present exemplary embodiment, fabric sheets or plastic films can be used.
As illustrated in
A stacking portion 11 (11a and 11b) is disposed at a lower portion of the recording apparatus 200 and can stack the plurality of sheets P. Each sheet P on which recording is performed by a recording unit (described below) is discharged to a discharge unit 25. In the case of performing double-sided recording on the sheets P, each sheet P fed from the stacking portion 11 is conveyed from the feed path 100 to the recording unit, so that the recording unit records an image on a front side of the sheet P that faces a recording head 7. The sheet P then reaches the reverse path 102. A traveling direction of the sheet P is reversed in the reverse path 102, and the sheet P is conveyed through the circulation path 101 and reaches the feed path 100 again.
Thereafter, the sheet P is conveyed from the feed path 100 to the recording unit, so that the recording unit records an image on a back side of the sheet P. The sheet P with the images formed on the front and back sides is discharged through the discharge path 104 to the discharge unit 25. Motors that rotate rollers include feed motors 206 (206a and 206b), a conveyance motor 205, a discharge motor 215, and a reverse motor 216, as illustrated in
A pickup roller 2 is brought into contact with the uppermost sheet P stacked on the stacking portion 11 to pick up the uppermost sheet P. The pickup roller 2 is driven by the feed motor 206a. The sheet P picked up by the pickup roller 2 is fed along the feed path 100 by a feed roller 3. The pickup roller 2 is a one-way roller. Thus, after the sheet P is conveyed to a position downstream of the feed roller 3 in the first conveyance direction, even if the pickup roller 2 is stopped, the conveyance of the sheet P by the feed roller 3 can be continued. A feed driven roller 4 is biased against the feed roller 3, and the feed roller 3 and the feed driven roller 4 hold the sheet P and convey the sheet P to the first conveyance roller 5 in the first conveyance direction. The feed roller 3 is driven by the feed motor 206b. A pinch roller 6 is biased against the first conveyance roller 5 at a position downstream of the feed roller 3 in the first conveyance direction, and the first conveyance roller 5 and the pinch roller 6 hold the sheet P and convey the sheet P. The first conveyance roller 5 conveys the sheet P to the recording unit in the first conveyance direction. Between the feed roller 3 and the first conveyance roller 5, the sheet P is guided by guides. On the feed path 100, the sensor 16 is disposed downstream of the feed roller 3 in the first conveyance direction, and detects a leading edge or a trailing edge of the sheet P. It takes a certain time for the sensor 16 to detect edge portions of the plurality of sheets P continuously. The plurality of sheets P is thus conveyed continuously at predetermined intervals or more. More specifically, it takes a predetermined time for the sensor 16 to detect a leading edge of the sheet P2 (the second fed sheet) in the conveyance direction after detecting a trailing edge of the sheet P1 (the first fed sheet) in the conveyance direction.
The recording unit includes the recording head 7, the first conveyance roller 5, a second conveyance roller 10, and a platen 8. The recording head 7 ejects ink to the sheet P. The first conveyance roller 5 and the second conveyance roller 10 convey the sheet P. The platen 8 supports the sheet P. The first conveyance roller 5 and the second conveyance roller 10 are driven by the conveyance motor 205. The recording head 7 is mounted on a carriage 1 and is moved in a sheet width direction intersecting the first conveyance direction. The carriage 1 is driven by a carriage motor 204 (see
The sheet P conveyed by the second conveyance roller 10 is conveyed to the discharge path 104 (in a direction E) or the reverse path 102 (in a direction F) by a third conveyance roller 20 as illustrated in
In the case of conveying the sheet P to the discharge path 104, the flapper 24a is at a first position. The sheet P conveyed by the second conveyance roller 10 is conveyed by the third conveyance roller 20, the first discharge roller 22, and a second discharge roller 26. The first discharge roller 22, the second discharge roller 26, and the third conveyance roller 20 are driven by the discharge motor 215. In the case of conveying the sheet P to the reverse path 102, the flappers 24a and 24b are at a second position. On the reverse path 102, the reverse roller 9 and the second reverse roller 27 are rotated in a forward direction (a direction A) and a reverse direction (a direction B) by the reverse motor 216. A reverse driven roller 13 is biased against the reverse roller 9, and the reverse driven roller 13 and the reverse roller 9 hold the sheet P and convey the sheet P. In a case where the reverse roller 9 is rotated in the forward direction, the sheet P is conveyed in a direction (a direction C) that exposes the sheet P from the recording apparatus 200. After a trailing edge portion of the sheet P passes the flapper 24b, the reverse roller 9 and the second reverse roller 27 are rotated in the reverse direction by the reverse motor 216. The sheet P having passed the flapper 24b is detected by the sensor 18. In a case where the sheet P2 overlaps the sheet P1, the sheet P2 is detected by the sensor 18. In the case of the absence of the sensor 18, the position of the trailing edge of the sheet P is estimated based on the conveyance amount of the sheet P.
After the flapper 24b is switched from the second position to the first position, the reverse roller 9 and the second reverse roller 27 are rotated in the reverse direction (the direction B). As a result, the traveling direction of the sheet P is successfully reversed. In a case where the second sheet P2 overlaps the sheet P1, the traveling direction of the sheet P1 and the traveling direction of the second sheet P2 are each reversed. The sheet P is then conveyed in a direction D toward the circulation path 101 through the reverse path 102 along the guides. Intermediate rollers 15a, 15b, and 15c are rotated by a predetermined amount to convey the sheet P to the feed roller 3. On the circulation path 101, the intermediate rollers 15a, 15b, and 15c are each driven by the reverse motor 216. A configuration that detects the leading edge of the sheet P in the second conveyance direction using the sensor 19 can be used. In the circulation path 101, the sheets P1 and P2 can be retained to adjust the timing of conveying the sheets P1 and P2 and the timing of feeding the sheets P3 and P4 from the stacking portion 11.
The recording head 7 is controlled by a recording head driver 218 and ejects ink. The carriage 1 is driven by the carriage motor 204 and can move back and forth in the sheet width direction.
The pickup roller 2 is driven by the feed motor 206a. The feed roller 3 is driven by the feed motor 206b. The first conveyance roller 5 and the second conveyance roller 10 are driven by the conveyance motor 205. The various motors are controlled by a motor driver 219 representing a plurality of motor drivers. The various rollers are each provided with an encoder sensor (not illustrated) for detecting passage of light through slits of a code wheel. The control unit 201 detects the conveyance speed and amount of each roller by counting the numbers of slits of the encoder sensor through which the light passes. The code wheel and the encoder sensor are not necessarily positioned coaxially with the corresponding roller. The flappers 24 (24a and 24b) are driven by the flapper solenoid 217. The flapper solenoid 217 is controlled by the solenoid driver 220.
A case where double-sided recording is performed on four sheets P1 to P4 in a single job will be described.
The recording order is not limited thereto. For example, the recording apparatus 200 can be configured to discharge the sheets P with the front sides facing upward to the stacking portion 11 provided on the rear side and diverged from the reverse path 102. In this case, the control unit 201 feeds the sheet P3 fed third, the sheet P4 fed fourth, the sheet P1 fed first, and the sheet P2 fed second in this order and performs the recording operation on both the back and front sides. Consequently, the fourth sheet, the third sheet, the second sheet, and the first sheet are discharged in this order from the bottom with the front sides facing upward. Further, in the present example, the sheet P1 is recorded in a state where the leading edge of the sheet P2 overlaps the sheet P1, and the sheet P3 is recorded in a state where the sheet P4 overlaps the sheet P3. There may be a case where recording data does not satisfy an overlapping condition and the sheets P1 and P2 are not to be overlapped or a case where recording data does not satisfy the overlapping condition and the sheets P3 and P4 are not to be overlapped. In the case of continuous recording on the sheets P, a combination of a case where the sheets P are to be overlapped and a case where the sheets P are not to be overlapped can be set based on recording data. Further, in the case of continuous one-sided recording, the sheets P are discharged with the front sides facing downward without being conveyed to the reverse path 102. In this case, the control unit 201 performs the recording operation to record the recording data corresponding to the first sheet on the front side of the sheet P1 fed first, the recording data corresponding to the second sheet on the front side of the sheet P2 fed second, the recording data corresponding to the third sheet on the front side of the sheet P3 fed third, and the recording data corresponding to the fourth sheet on the front side of the sheet P4 fed fourth in this order.
Flowcharts illustrating the recording operation will be described below with reference to
When recording data for double-sided recording is transmitted from the host computer 214 via the OF unit 213, the control unit 201 performs step S30 to start a double-sided recording operation.
In step S301, the control unit 201 sets the recording order number N to 1. In step S302, the control unit 201 acquires the maximum recording order number Nmax based on the recording data. In step S303, the control unit 201 pivotally moves the flappers 24a and 24b in advance to prepare for the post-recording processing G(N) on the M(N)-th sheet P on which the recording is performed.
In step S304, the control unit 201 starts feeding of the M(N)-th sheet P from the feed source Q(N) to achieve a feed speed of 7.6 inch/sec. In a case where the feed source Q(N) is the stacking portion 11, the feed motor 206a is driven at low speed, whereby the pickup roller 2 is rotated to achieve a feed speed of 7.6 inch/sec. When the pickup roller 2 is rotated, the uppermost sheet P stacked on the stacking portion 11 is picked up. The sheet P picked up by the pickup roller 2 is fed by the feed roller 3 being rotated in the same direction as the rotation direction of the pickup roller 2. The feed roller 3 is driven to achieve the same feed speed as that of the pickup roller 2. The pickup roller 2 feeds the sheet P to a position downstream of the feed roller 3 in the first conveyance direction and is stopped to prevent the next sheet P from being picked up. In a case where the feed source Q(N) is the reverse path 102, the reverse motor 216 is reversed, and the feed motor 206b is driven at low speed. Consequently, the intermediate rollers 15a, 15b, and 15c and the feed roller 3 are rotated to achieve a conveyance speed of 7.6 inch/sec. Then, the sheet P is conveyed in the direction toward the first conveyance roller 5 from the circulation path 101 through the feed path 100 by the intermediate rollers 15a, 15b, and 15c and the feed roller 3.
In step S305, the control unit 201 determines whether the leading edge of the M(N)-th sheet P has passed the sensor 16. In a case where the control unit 201 determines that the leading edge of the M(N)-th sheet P has not passed the sensor 16 (NO in step S305), the processing of step S305 is repeated. In a case where the control unit 201 determines that the leading edge of the M(N)-th sheet P has passed the sensor 16 (YES in step S305), the processing proceeds to step S306. In step S306, the control unit 201 switches the feed motor 206b to high-speed driving to convey the M(N)-th sheet at a conveyance speed of 20 inch/sec. Consequently, in a case where the preceding sheet P, i.e., the M(N−1)-th sheet P is present, the M(N)-th sheet P reaches the M(N−1)-th sheet P.
In step S307, the control unit 201 determines whether the recording order number N is 1. In a case where the control unit 201 determines that the recording order number N is 1 (YES in step S307), since the preceding sheet P is not present, the processing proceeds to step S308. In a case where the control unit 201 determines that the recording order number N is not 1 (NO in step S307), since there is a possibility of continuous conveyance in an overlapping state, the processing proceeds to step S40 to perform the overlapping preparation operation.
The overlapping preparation operation in step S40 will be described with reference to
In step S402, the control unit 201 determines whether a predetermined overlapping condition is satisfied. In a case where the control unit 201 determines that the overlapping condition is satisfied (YES in step S402), the processing proceeds to step S403. In step S403, the control unit 201 determines whether the recording of the last line on the M(N−1)-th sheet P, on which the recording is being performed, has started. In a case where the recording of the last line on the M(N−1)-th sheet P has started (YES in step S403), the processing proceeds to step S308 in
In a case where the control unit 201 determines that the overlapping condition is not satisfied (NO in step S402), the processing proceeds to step S404. A case where the overlapping condition is not satisfied is, for example, a case where the M(N−1)-th sheet P does not have enough margins for overlapping. By sequentially performing steps S404 to S407 (described below), it is possible to perform an operation of cancelling an overlapping state or an operation for a case where the M(N)-th sheet P is unable to reach the preceding sheet P, i.e., the M(N−1)-th sheet P.
In step S404, the control unit 201 determines whether the recording of the last line on the M(N−1)-th sheet P has ended. In a case where the control unit 201 determines that the recording of the last line on the M(N−1)-th sheet P has not ended (NO in step S404), the processing of step S404 is repeated. In a case where the control unit 201 determines that the recording of the last line on the M(N−1)-th sheet P has ended (YES in step S404), the processing proceeds to step S405. In step S405, the control unit 201 conveys the M(N−1)-th sheet P using the first conveyance roller 5 at a conveyance speed of 18 inch/s. In step S406, the control unit 201 determines whether the M(N−1)-th sheet P has been conveyed by a predetermined amount or more after the trailing edge of the M(N−1)-th sheet P passes the first conveyance roller 5.
In a case where the control unit 201 determines that the M(N−1)-th sheet P has been conveyed by the predetermined amount or more after the trailing edge of the M(N−1)-th sheet P passes the first conveyance roller 5 (YES in step S406), the processing proceeds to step S407. In step S407, the control unit 201 stops the first conveyance roller 5, and the processing proceeds to step S308 in
By performing steps S404 to S407 as described above, in a case where the sheets P are in an overlapping state but the overlapping condition is not satisfied, the overlapping state is canceled. In a case where the overlapping state is canceled or in a case where the M(N)-th sheet P is unable to reach the M(N−1)-th sheet P, a preparation for skew correction on the M(N)-th sheet P alone is performed.
In step S308, the control unit 201 performs the skew correction on the M(N)-th sheet P.
When the feed roller 3 is driven while the first conveyance roller 5 is stopped for the ejection operation, the leading edge of the M(N)-th sheet P hits a conveyance nip portion. Consequently, the skew of the M(N)-th sheet P is corrected. In a case where the overlapping condition in step S402 is satisfied, the skew of the M(N)-th sheet P is corrected in the overlapping state with the M(N−1)-th sheet P. In a case where the preceding sheet P is not present, the skew correction is performed on the M(N)-th sheet P alone. In a case where the overlapping condition is not satisfied, the skew correction is performed on the M(N)-th sheet P alone.
In step S309, the control unit 201 aligns the print start position of the M(N)-th sheet P. By rotating the first conveyance roller 5 by a predetermined amount, it is possible to align the print start position of the M(N)-th sheet P. At this time, in a case where the skew correction is performed on the M(N)-th sheet P in the overlapping state with the M(N−1)-th sheet P, the print start position of the M(N)-th sheet P is aligned while the overlapping state is maintained.
In step S310, the control unit 201 switches the feed speed of the M(N)-th sheet P to 7.6 inch/sec. When the feed motor 206b is switched to low-speed driving, the feed roller 3 is rotated at 7.6 inch/sec.
In step S311, the control unit 201 starts the recording operation of recording the data corresponding to the K(N)-th sheet on the F(N) side of the M(N)-th sheet P. While the M(N)-th sheet P is conveyed by a predetermined amount intermittently by the first conveyance roller 5, the feed roller 3 is also driven intermittently. During the intermittent conveyance, the ejection operation is performed, and the recording is performed sequentially.
In step S312, the control unit 201 determines whether the recording order number N is 1. In a case where the control unit 201 determines that the recording order number N is 1 (YES in step S312), the processing proceeds to step S313. In a case where the control unit 201 determines that the recording order number N is not 1 (NO in step S312), the processing proceeds to step S316.
In step S316, the control unit 201 determines whether the overlapping has been performed. In a case where the control unit 201 determines that the overlapping has been performed (YES in step S316), the processing proceeds to step S317. In step S317, the control unit 201 conveys the overlapping sheets P while maintaining the overlapping state and performs the reversing/discharging operation in step S60. In a case where the control unit 201 determines that the overlapping has not been performed (NO in step S316), the reversing/discharging operation is performed on the sheet P alone in step S60.
The reversing/discharging operation in step S60 will be described with reference to
In step S603, the control unit 201 determines whether the trailing edge of the M(N−1)-th sheet P has passed the flapper 24b. The determination of whether the trailing edge of the M(N−1)-th sheet P has passed the flapper 24b is performed based on the amounts of rotation of the various rollers. In a case where the sensor 18 is provided, the determination can be performed based on a signal from the sensor 18. In a case where the control unit 201 determines that the trailing edge of the M(N−1)-th sheet P has passed the flapper 24b (YES in step S603), the processing proceeds to step S604.
In step S604, the control unit 201 pivotally moves the flappers 24a and 24b to prepare for the post-recording processing G(N) on the M(N)-th sheet as the next recording target.
In step S605, the control unit 201 continuously conveys the M(N−1)-th sheet P until the trailing edge of the M(N−1)-th sheet P reaches a predetermined position upstream of the reverse roller 9 in the first conveyance direction. After the trailing edge of the M(N−1)-th sheet P reaches the predetermined position, the processing proceeds to step S606. In step S606, the control unit 201 reverses the conveyance direction of the M(N−1)-th sheet P and conveys the M(N−1)-th sheet P to the circulation path 101. By switching the reverse motor 216 to the high-speed driving in the reverse rotation, the reverse roller 9 and the intermediate rollers 15a, 15b, and 15c are driven to achieve a conveyance speed of 18 inch/sec. In step S607, the control unit 201 conveys the M(N−1)-th sheet P until the leading edge of the M(N−1)-th sheet P in the second conveyance direction reaches a predetermined position of the feed path 100. After the processing of step S607 is ended, the processing proceeds to step S313 in
In a case where the control unit 201 determines that the post-recording processing G(N−1) on the preceding sheet P (the M(N−1)-th sheet P) is the discharging operation (NO in step S601), the processing proceeds to step S608. In step S608, the control unit 201 discharges the M(N−1)-th sheet P to the discharge unit 25 by rotating the first discharge roller 22 and the third conveyance roller 20. In a case where the M(N−1)-th sheet P is in the overlapping state with the M(N)-th sheet, the overlapping state is canceled.
In step S609, the control unit 201 determines whether the trailing edge of the M(N−1)-th sheet P in the first conveyance direction has passed the flapper 24a. The determination of whether the trailing edge of the M(N−1)-th sheet P in the first conveyance direction has passed the flapper 24a is performed based on the amounts of rotation of the various rollers. Alternatively, a sensor can be provided, and the determination can be performed using the sensor. In a case where the control unit 201 determines that the trailing edge of the M(N−1)-th sheet P in the first conveyance direction has passed the flapper 24a (YES in step S609), the processing proceeds to step S610.
In step S610, the control unit 201 pivotally moves the flappers 24a and 24b to prepare for the post-recording processing G(N) on the M(N)-th sheet P as the next recording target. After the processing of step S610 is ended, the processing proceeds to step S313 in
In step S313, the control unit 201 increments the recording order number N and sets the recording order number N to N+1.
In step S314, the control unit 201 determines whether the recording order number N is less than or equal to the maximum recording order number Nmax. In a case where the control unit 201 determines that the recording order number N is less than or equal to the maximum recording order number Nmax (YES in step S314), the processing proceeds to step S315. In step S315, the control unit 201 determines whether the trailing edge of the M(N−1)-th sheet P has passed the sensor 16. In a case where the control unit 201 determines that the trailing edge of the M(N−1)-th sheet P has passed the sensor 16 (YES in step S315), the processing returns to step S304.
In a case where the control unit 201 determines that the recording order number N is greater than the maximum recording order number Nmax (NO in step S314), the processing proceeds to step S318. In step S318, the control unit 201 discharges the M(N−1)-th sheet P. Rotating the first discharge roller 22, the third conveyance roller 20, the second conveyance roller 10, and the first conveyance roller 5 in the same direction enables discharging the M(N−1)-th sheet P to the discharge unit 25. In this manner, the M(Nmax)-th sheet P is discharged, so that the recording operation is ended after all the sheets P are discharged.
A case where the recording is performed in the recording order specified in
As indicated by the state ST2, in a case where the feed roller 3 is continuously rotated, the leading edge of the sheet P1 in the first conveyance direction hits the conveyance nip portion formed by the first conveyance roller 5 and the pinch roller 6.
At this time, the first conveyance roller 5 is being stopped. The control unit 201 rotates the feed roller 3 by a predetermined amount in a state where the leading edge of the sheet P1 hits the conveyance nip portion. Consequently, the sheet P1 becomes parallel to the first conveyance roller 5, and the skew of the sheet P1 is corrected. Further, the leading edge of the sheet P1 is positioned at the position of the first conveyance roller 5 by hitting the conveyance nip portion. Thereafter, the control unit 201 performs control to align the print start position of the sheet P1 and convey the sheet P1, using the position of the first conveyance roller 5 as a reference.
After the skew correction on the sheet P1 is ended, the control unit 201 starts rotating the first conveyance roller 5 using the conveyance motor 205 as indicated by the state ST3. At this time, the first conveyance roller 5 conveys the sheet P1 at a conveyance speed of 15 inch/sec, so that the print start position of the sheet P1 is aligned with a position facing the recording head 7. Thereafter, the control unit 201 starts the recording operation of recording the recording data corresponding to the back side of the second sheet on the top side of the sheet P1 that faces the recording head 7 by ejecting ink from the recording head 7.
After the print start position of the sheet P1 is aligned, the control unit 201 switches the feed motor 206b to the low-speed driving. More specifically, the feed roller 3 is rotated to feed the sheet P1 at a feed speed of 7.6 inch/sec. While the sheet P1 fed first is conveyed by a predetermined amount intermittently by the first conveyance roller 5, the feed roller 3 is driven intermittently in synchronization with the first conveyance roller 5. More specifically, while the first conveyance roller 5 is rotated, the feed roller 3 is also rotated, and while the first conveyance roller 5 is stopped, the feed roller 3 is also stopped. The rotation speed of the feed roller 3 is controlled to be lower than the rotation speed of the first conveyance roller 5. Thus, the sheet P1 is stretched between the first conveyance roller 5 and the feed roller 3. The feed roller 3 is dragged by the sheet P1 being conveyed by the first conveyance roller 5. While the sheet P1 is conveyed by a predetermined amount intermittently by the first conveyance roller 5, the third conveyance roller 20 is driven intermittently to achieve the same sheet conveyance speed as that of the first conveyance roller 5.
As indicated by the state ST4, the sheet P2 picked up second by the pickup roller 2 is fed by the feed roller 3. At this time, the recording is being performed on the sheet P1 by the recording head 7 based on the recording data corresponding to the back side of the second sheet. When the leading edge of the sheet P2 is detected by the sensor 16, the control unit 201 switches the feed motor 206b to continuous conveyance. At this time, the feed roller 3 is driven to achieve a conveyance speed of 20 inch/sec for high-speed driving. Alternatively, the feed motor 206b can be switched to the continuous conveyance when the trailing edge of the sheet P1 is detected by the sensor 16.
As indicated by the state ST5, since the conveyance speed of the sheet P2 is higher than the conveyance speed of the sheet P1 in the recording operation, the leading edge of the sheet P2 is overlapped on the sheet P1. More specifically, since the recording operation is being performed on the sheet P1 based on the recording data corresponding to the back side of the second sheet, the sheet P1 is conveyed intermittently by the first conveyance roller 5 at a conveyance speed of 7.6 inch/sec. Meanwhile, the sheet P2 on which the recording is to be performed next by the recording head 7 is continuously conveyed at a conveyance speed of 20 inch/sec using the feed roller 3 after the leading edge of the sheet P2 is detected by the sensor 16, thereby reaching the sheet P1. Thereafter, the sheet P2 is fed by the feed roller 3 until the leading edge of the sheet P2 is stopped at a predetermined position upstream of the conveyance nip portion in the first conveyance direction. The position of the leading edge of the sheet P2 is calculated based on the amount of rotation of the feed roller 3 after the detection of the leading edge of the sheet P2 in the conveyance direction by the sensor 16, and the control is performed based on this calculation result. In recording the last line on the sheet P1, the control unit 201 rotates the feed roller 3 by a predetermined amount in a state where the leading edge of the sheet P2 hits the conveyance nip portion. During the ejection operation by the recording head 7, the first conveyance roller 5 is stopped. Consequently, the sheet P2 becomes parallel to the first conveyance roller 5, and the skew of the sheet P2 is corrected. In a case where the sensor 17 is provided upstream of the first conveyance roller 5, the sheet P2 can be stopped at a predetermined position upstream of the conveyance nip portion based on detection by the sensor 17.
At this time, the flapper 24a is at the second position, and the flapper 24b is at the second position. Thus, the sheet P1 on which the recording is completed is conveyed to the reverse path 102 by the rotation of the third conveyance roller 20. Meanwhile, the control unit 201 performs the recording operation on the sheet P2 following the sheet P1. The control unit 201 performs the recording operation on the sheet P2 using the recording head 7 based on the recording data corresponding to the back side of the first sheet. After the recording of the last line on the sheet P2 is ended, as indicated by the state ST6, the control unit 201 conveys the sheets P1 and P2 to the reverse path 102 by rotating the third conveyance roller 20 by a predetermined amount while maintaining the overlapping state of the sheets P1 and P2. During the foregoing process, the control unit 201 further performs the pickup operation of the sheet P3 to be picked up third, using the pickup roller 2. Thereafter, the sheet P3 picked up by the pickup roller 2 is fed continuously by the feed roller 3 with an interval between the sheets P2 and P3. At this time, the leading edge of the sheet P3 is not overlapped on the sheet P2.
After the trailing edge of the sheet P2 passes the flapper 24b, the control unit 201 switches the flapper 24b to the first position. Thereafter, the control unit 201 rotates the second reverse roller 27 and the reverse roller 9 in the reverse direction (the direction B). Consequently, as indicated by the state ST8, the traveling direction of the sheets P1 and P2 is reversed from the direction C to the direction D while the overlapping state of the sheets P1 and P2 is maintained. Then, the sheets P1 and P2 are guided to the circulation path 101 along guides of the reverse path 102.
As indicated by the state ST9, after the traveling direction is reversed, the sheet P2 precedes the sheet P1 and is conveyed through the circulation path 101. At this time, the control unit 201 starts the recording operation on the sheet P3 based on the recording data corresponding to the back side of the fourth sheet. In this state, the control unit 201 performs the overlapping operation to overlap the leading edge of the sheet P4 on the sheet P3. More specifically, since the recording operation is being performed on the sheet P3 based on the recording data, the sheet P3 is conveyed intermittently by the first conveyance roller 5. Meanwhile, the sheet P4 is continuously conveyed at a conveyance speed of 20 inch/sec by the feed roller 3 after the leading edge of the sheet P4 is detected by the sensor 16, thereby reaching the sheet P3. Thereafter, the sheet P4 is fed by the feed roller 3 until the leading edge of the sheet P4 is stopped at a predetermined position upstream of the conveyance nip portion in the first conveyance direction. Since the conveyance speed of the sheet P4 is higher than the conveyance speed of the sheet P3 in the recording operation, the leading edge of the sheet P4 is overlapped on the sheet P3. In recording the last line on the sheet P3, the control unit 201 rotates the feed roller 3 by a predetermined amount in a state where the leading edge of the sheet P4 hits the conveyance nip portion. During the ejection operation by the recording head 7, the first conveyance roller 5 is stopped. Consequently, the sheet P4 becomes parallel to the first conveyance roller 5, and the skew of the sheet P2 is corrected.
As indicated by the state ST10, to re-feed the sheet P2 to the recording head 7, the control unit 201 feeds the sheet P2 at high speed. Consequently, the leading edge of the sheet P2 is overlapped on the sheet P4 on which the recording is being performed by the recording head 7 based on the recording data corresponding to the back side of the third sheet. There may be a case where the sheet P2 is unable to be overlapped on the sheet P4, depending on the recording data. In this case, the control unit 201 does not perform control to overlap the sheet P2 on the sheet P4.
In a case where the sheet P2 is to be overlapped on the sheet P4, in recording the last line on the sheet P4, the control unit 201 rotates the feed roller 3 by a predetermined amount in a state where the leading edge of the sheet P2 hits the conveyance nip portion. While the ejection operation is performed by the recording head 7 during the intermittent conveyance, the first conveyance roller 5 is stopped. Consequently, the sheet P2 becomes parallel to the first conveyance roller 5, and the skew of the sheet P2 is corrected. The sheet P3 on which the recording is performed by the recording head 7 is conveyed to the reverse path 102 by the third conveyance roller 20 while the overlapping state with the sheet P4 is maintained. Following the conveyance of the sheet P3, the recording is performed on the sheet P4 by the recording head 7 based on the recording data corresponding to the back side of the third sheet. After completion of the recording on the sheet P4, the sheets P3 and P4 are conveyed to the reverse path 102. More specifically, the sheets P3 and P4 are conveyed to the reverse path 102 while the overlapping state of the sheets P3 and P4 is maintained. At this time, the overlapping state of the sheets P4 and P2 is canceled.
As indicated by the state ST11, after the recording is performed on the sheet P4, the control unit 201 re-feeds the sheet P2 to the recording head 7. The recording is performed on the sheet P2 by the recording head 7 based on the recording data corresponding to the front side of the first sheet. At this time, the control unit 201 rotates the third conveyance roller 20 and the first discharge roller 22 using the discharge motor 215 independently of the first conveyance roller 5 and the second conveyance roller 10. Consequently, the overlapping state of the sheets P4 and P2 is canceled. Thereafter, the control unit 201 rotates the second reverse roller 27 and the reverse roller 9 in the forward rotation (the direction A) to convey the sheet P3 in the direction C to expose part of the sheet P3 from the recording apparatus 200. Further, the control unit 201 conveys the sheet P4 by rotating the second reverse roller 27 in the forward direction until the trailing edge of the sheet P4 in the first conveyance direction passes the flapper 24b.
As indicated by the state ST12, after the recording is performed on the sheet P2, the control unit 201 re-feeds the sheet P1 to the recording head 7. The recording is performed on the sheet P1 by the recording head 7 based on the recording data corresponding to the front side of the second sheet. Meanwhile, after the trailing edge of the sheet P4 passes the flapper 24b, the control unit 201 switches the flapper 24b to the first position. Thereafter, the control unit 201 rotates the second reverse roller 27 and the reverse roller 9 in the reverse direction (the direction B). Consequently, the traveling direction of the sheets P3 and P4 is reversed while the overlapping state of the sheets P3 and P4 is maintained, and the sheets P3 and P4 are conveyed in the direction D toward the circulation path 101 through the reverse path 102 along the guides. There may be a case where the sheet P1 is unable to be overlapped on the sheet P2, depending on the recording data. In this case, the control unit 201 cancels the overlapping state of the sheets P2 and P1 and then performs the recording on the sheet P1.
After the sheets P2 and P1 are separated from each other, in the state ST14, the sheet P2 is discharged to the discharge unit 25 by the first discharge roller 22. Meanwhile, the control unit 201 performs the recording operation on the sheet P1 based on the recording data corresponding to the front side of the second sheet. Thereafter, the control unit 201 performs the recording operation on the sheet P4 based on the recording data corresponding to the front side of the third sheet. The control unit 201 rotates the third conveyance roller 20 and the first discharge roller 22 using the discharge motor 215 independently of the first conveyance roller 5 and the second conveyance roller 10. Consequently, the sheet P2 is discharged to the discharge unit 25 in a state where the front side thereof faces downward. In some embodiment, the recording may be performed on the sheets P4 and P3 after the overlapping state of the sheets P4 and P3 is canceled by setting of different speeds for the feed roller 3 and the intermediate rollers 15a, 15b, and 15c based on the recording data. In this case, the sheets P4 and P3 are conveyed to the recording head 7 with an interval between the sheets P4 and P3 and are each discharged to the discharge unit 25 thereafter.
In the state ST15, the sheet P1 is discharged to the discharge unit 25 by the first discharge roller 22 in a state where the front side thereof faces downward. Meanwhile, the recording on the sheet P4 is ended, and the sheet P4 is conveyed by the third conveyance roller 20 and the first discharge roller 22. At this time, the control unit 201 performs the recording on the sheet P3 based on the recording data corresponding to the front side of the fourth sheet.
The above-described exemplary embodiment provides a recording apparatus that improves productivity in double-sided recording on a plurality of sheets by reversing the traveling direction of a preceding sheet and a subsequent sheet and conveying the sheets through a reverse path while maintaining an overlapping state of the sheets.
Embodiment(s) of the present disclosure can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2022-182933, filed Nov. 15, 2022, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2022-182933 | Nov 2022 | JP | national |