Patent Grant
7722182
This application claims priorities from Japanese Patent Applications No. 2005-375952 filed on Dec. 27, 2005 and No. 2005-379602 filed on Dec. 28, 2005. The entire content of each of these priority applications is incorporated herein by reference.
The disclosure relates to an inkjet-recording device and components employed in this device, and particularly to the structure of a component functioning to drive a movable support piece provided on a platen.
An inkjet-recording device includes a recording head with a plurality of juxtaposed nozzles. A recording paper is conveyed below the recording head while the recording head forms an image on the paper. The recording head records an image on the recording paper by moving in a main scanning direction (orthogonal to the paper-conveying direction), while ejecting ink droplets from the nozzles at a prescribed timing. In recent years, inkjet-recording devices have been provided with a photo printing function. This type of image recording is called “borderless recording” because the image is recorded without leaving margins on the edges of the recording paper.
In borderless recording, the recording head is moved beyond the edges of the paper and ink is ejected to a point outside the region occupied by the recording paper. For example, in Japanese unexamined patent application publication No. 2000-118058, when borderless recording is performed on the leading and trailing edges of the recording paper, the recording paper is positioned relative to the recording head so that a portion of the nozzles in the recording head is positioned off the edge of the recording paper. Consequently, the recording head ejects ink droplets through these nozzles onto a platen provided below the recording paper. The platen is provided with a groove formed in the top portion thereof and extending in the main scanning direction, and an ink absorbing material disposed inside this groove for absorbing the ink droplets. This configuration makes it possible to record an image over the entire recording paper, without leaving a border along the edges of the recording paper, while preventing ink ejected onto the platen from staining the underside of the recording paper.
There has also been a demand in recent years for inkjet-recording devices capable of recording images at a faster rate. Conventional attempts to increase the image recording speed have involved increasing the size of the recording head in order to increase the number of nozzles arranged in the paper-conveying direction. However, in order to perform high-quality borderless recording, it has been necessary to increase the width (dimension in the paper-conveying direction) of the groove provided in the platen as the size of the recording head is increased.
However, since the recording paper is positioned above this groove when performing borderless recording, an increased groove width may cause the recording paper to deform, bending downward into the groove. Such bending of the recording paper changes the distances between nozzles in the recording head and the surface of the recording paper, potentially leading to recording problems.
To resolve this problem, Japanese unexamined patent application publications Nos. 2001-80145 and 2002-307769 proposed providing paper support members in the groove formed in the platen. These paper support members rotate along with the recording paper as the recording paper is conveyed. The paper support members support the recording paper advancing over the groove, while moving in the width direction of the groove. Hence, the paper support members can support the recording paper when the recording paper is conveyed over the groove formed in the platen.
However, since the conventional paper support members rotate about a prescribed rotational shaft (see Japanese unexamined patent application publication No. 2001-80145), the distal edges of the paper support members (the portion contacting the recording paper) first approach and then separate from the recording head side. Therefore, the recording paper is not always supported parallel to the recording head. While this problem can be resolved by sufficiently increasing the rotational radius of the paper support members, doing so would also increase the size of the inkjet-recording device. Some devices have paper support members with surfaces for supporting the recording paper in the shape of an arc centered on the rotational shaft. However, this structure fixes the points at which the recording paper is supported so that the edges of the conveyed recording paper are not always supported. In other words, when the surfaces supporting the recording paper are formed in arc shapes, the recording paper is only supported at the support points and can bend in regions outside the support points (areas in front of or behind the support points), potentially leading to the same recording problems described above.
In view of the foregoing, it is an object of the invention to provide an inkjet-recording device capable of performing high-speed borderless recording while ensuring that the edges of the conveyed recording paper are always supported on the platen.
In order to attain the above and other objects, the invention provides an inkjet-recording device including a recording head, a platen, a conveying member, and a movable supporting member. The recording head ejects ink droplets onto a recording medium. The platen is disposed in confrontation with the recording head to support the recording medium while keeping a predetermined distance from the recording head. The conveying member conveys the recording medium in a conveying direction. The movable supporting member is linked to the conveying member to slide in the conveying direction while supporting the recording medium.
Another aspect of the invention provides a driving unit for sliding a movable supporting member from a first part to a second part in a conveying direction of a recording medium while supporting the recording medium on a platen. The movable supporting member has an engaging portion. The driving unit includes a rotating plate having a rotational shaft, rotatable about the rotational shaft, and formed with a guide groove engagable with the engaging portion to guide the engaging portion in the conveying direction as the rotating plate rotates.
The above and other objects, features and advantages of the invention will become more apparent from reading the following description of the preferred embodiments taken in connection with the accompanying drawings in which:
Next, the invention will be described in detail based on preferred embodiments, while referring to the accompanying drawings. These embodiments are merely examples of the invention, and it should be apparent to those skilled in the art that many modifications and variations may be made therein without departing from the spirit of the invention.
The multifunction device 1 possesses a printer function, scanner function, copier function, and facsimile function, specifically, is integrally provided with a printer section 2 in the lower section and configured of an inkjet-recording device; and a scanner section 3 in the upper section. Alternatively, it is possible to omit all functions from the multifunction device 1 except the printer function. For example, the multifunction device 1 may be configured as a stand-alone printer by omitting the scanner section 3. The features of the preferred embodiment are as follows. As will be described later with reference to
The printer section 2 of the multifunction device 1 is primarily connected to a computer or other external information device for recording text and images on a recording paper based on print data including text or image data transmitted from the computer or the like. The multifunction device 1 may also be connected to a digital camera or the like and may record image data inputted from the digital camera on recording paper. Also, the multifunction device 1 may be loaded with a memory card or other storage medium and may be capable of recording image data and the like stored on the storage medium on recording paper.
As shown in
The scanner section 3 disposed in the upper section of the multifunction device 1 is a flatbed scanner. As shown in
A control panel 4 is provided on the top front surface of the multifunction device 1 for operating the printer section 2 and the scanner section 3. The control panel 4 is configured of various operating buttons and a liquid crystal display. The multifunction device 1 operates based on operating instructions inputted through the control panel 4 and, when connected to an external computer, operates based on instructions that the computer transmits through a printer driver or a scanner driver. A slot section 5 in which various small memory cards or other storage media can be inserted is provided in the upper left section of the multifunction device 1 on the front surface thereof (see
Next, the internal structure of the multifunction device 1, and particularly the structure of the printer section 2, will be described.
As shown in
As shown in
The feeding arm 26 is rotatably supported on a base end 26a. When the feeding arm 26 pivots about the base end 26a, the feeding roller 25 moves vertically so as to contact and separate from the feeding tray 20. The feeding arm 26 is urged to rotate downward into contact with the feeding tray 20 by its own weight, a spring, or the like, and retracts upward when the feeding tray 20 is inserted or removed. When the feeding arm 26 is pivoted downward, the feeding roller 25 supported on the end of the feeding arm 26 contacts the recording paper in the feeding tray 20 with pressure. As the feeding roller 25 rotates in this position, a frictional force generated between the surface of the feeding roller 25 and the recording paper conveys the topmost sheet of the recording paper toward the sloped separating plate 22. The leading edge of this sheet of recording paper contacts the sloped separating plate 22 and is guided upward by the sloped separating plate 22 onto the paper-conveying path 23. In some cases, when the feeding roller 25 is conveying the topmost sheet of recording paper, friction or static electricity between the topmost sheet and the underlying sheet causes the underlying sheet to be conveyed together with the topmost sheet. However, the underlying sheet is restrained when contacting the sloped separating plate 22.
Excluding the section in which the image-recording unit 24 and the like are provided, the paper-conveying path 23 is configured of an outer guide surface and an inner guide surface that oppose each other with a prescribed gap formed therebetween. For example, a curved section 17 of the paper-conveying path 23 may be configured near the rear side of the multifunction device 1 by fixing an outer guide member 18 and an inner guide member 19 to a frame of the multifunction device 1. Rollers 16 are provided along the paper-conveying path 23, and particularly in the curved section of the paper-conveying path 23. The rollers 16 are rotatably provided on axes extending in the width direction of the paper-conveying path 23 The surfaces of the rollers 16 are exposed from the outer guide surface. These rollers 16 facilitate the smooth conveyance of recording paper in the curved section of the paper-conveying path 23.
As shown in
As shown in
The guide rail 43 disposed on the upstream side of the guide rail 44 in the paper-conveying direction is plate-shaped with a dimension in the width direction of the paper-conveying path 23 (left-to-right direction in
The guide rail 44 has an edge part 45 bent upward at substantially a right angle from the upstream side of the guide rail 44. The carriage 38 supported on the guide rails 43 and 44 has a pair of rollers or other gripping members for slidably gripping the edge part 45. Hence, the carriage 38 can slide in a direction orthogonal to the paper-conveying direction, while being positioned relative to the paper-conveying direction. In other words, the carriage 38 is slidably supported on the guide rails 43 and 44 and is capable of reciprocating in a direction orthogonal to the paper-conveying direction with the edge part 45 of the guide rail 44 serving as a positional reference. Although not shown in the drawings, a lubricating agent such as grease is applied to the edge part 45 to facilitate sliding of the carriage 38.
A belt drive mechanism 46 is provided on the top surface of the guide rail 44. The belt drive mechanism 46 is configured of a drive pulley 47 and a follow pulley 48 disposed near widthwise ends of the paper-conveying path 23, and an endless timing belt 49 stretched around the drive pulley 47 and follow pulley 48 and having teeth on the inside surface thereof. A carriage motor 73 (see
The bottom surface of the carriage 38 is fixed to the timing belt 49 so that the circuitous movement of the timing belt 49 causes the carriage 38 to reciprocate over the guide rails 43 and 44 while the edge part 45 maintains the position of the carriage 38 relative to the paper-conveying direction. The inkjet recording head 39 is mounted in the carriage 38 having this construction so that the inkjet recording head 39 also reciprocates in the width direction of the paper-conveying path 23. Here, the width direction of the paper-conveying path 23 is the main scanning direction.
As shown in
Light-transmitting parts allowing the passage of light and light-blocking parts preventing the passage of light are alternately disposed along the length of the encoder strip 50 at a prescribed pitch. An optical sensor 35 configured of a transmission sensor is disposed on the top surface of the carriage 38 at a position opposing the encoder strip 50. The optical sensor 35 reciprocates together with the carriage 38 along the length of the encoder strip 50 and detects the pattern formed on the encoder strip 50. A head controlling circuit board is provided in the inkjet recording head 39 for controlling ink ejection. The head controlling circuit board outputs a pulse signal based on detection signals from the optical sensor 35. By determining the position of the carriage 38 based on this pulse signal, it is possible to control the reciprocating motion of the carriage 38. The head controlling circuit board is covered by a head cover of the carriage 38 and is therefore not visible in
As shown in
As shown in
When an operation is performed to remove air bubbles and the like from the inkjet recording head 39, the carriage 38 is moved so that the inkjet recording head 39 is positioned above the cap 52. Subsequently, the moving mechanism moves the cap 52 upward against the inkjet recording head 39 so as to form a seal over the nozzles 53 formed in the bottom surface of the inkjet recording head 39. The pump mechanism then generates negative pressure in the cap 52 to draw out ink and air bubbles and foreign matter included in the ink from the nozzles 53.
The waste ink tray 84 is disposed on the top surface of the platen 42 outside of the image-recording range, but within the reciprocating range of the carriage 38 for receiving ink that has been flushed out of the inkjet recording head 39. The inside of the waste ink tray 84 is lined with felt for absorbing and holding the flushed ink. The maintenance unit having this construction can perform such maintenance as removing air bubbles and mixed ink of different colors from the inkjet recording head 39, and preventing the inkjet recording head 39 from drying out.
As shown in
The ink tubes 41 are tubes formed of synthetic resin and are flexible so as to be able to bend when the carriage 38 reciprocates. As shown in
Specifically, the section of the ink tubes 41 between the fixing clip 36 and carriage 38 leads in one direction along the reciprocating path of the carriage 38 and subsequently reverses directions, forming a curved section. In other words, this section of the ink tubes 41 is substantially U-shaped in a plan view. At the carriage 38, the four ink tubes 41 are horizontally juxtaposed along the paper-conveying direction and extend in the reciprocating direction of the carriage 38. However, the four ink tubes 41 are arranged vertically at the fixing clip 36 to facilitate fixation. The fixing clip 36 has a U-shaped cross-section open on the top. The vertically stacked ink tubes 41 are inserted through this opening and are integrally held by the fixing clip 36. In this way, the four ink tubes 41 curve along a U-shaped path from the carriage 38 to the fixing clip 36 while twisting from a horizontally juxtaposed relationship to a vertically juxtaposed relationship.
The four ink tubes 41 have substantially the same length from the carriage 38 to the fixing clip 36. The ink tube 41 positioned farthest upstream in the paper-conveying direction at the carriage 38 is positioned on the top at the fixing clip 36. The ink tube 41 disposed next in order from the upstream side at the carriage 38 is disposed next in order vertically at the fixing clip 36. This process is repeated so that the ink tubes 41 arranged from the upstream side to the downstream side in the paper-conveying direction at the carriage 38 are arranged in order from top to bottom at the fixing clip 36. Being substantially equivalent in length, the ink tubes 41 curve so that the center of the curved section of each ink tube 41 is offset in the paper-conveying direction according to the order in which the ink tubes 41 are juxtaposed in the paper-conveying direction. As a result, the four ink tubes 41 have a vertically sloped arrangement in the curved section, thereby minimizing interference among the ink tubes 41 as the ink tubes 41 change shape to follow the reciprocating motion of the carriage 38. In the preferred embodiment, four of the ink tubes 41 are provided. However, even if the number of the ink tubes 41 is increased, the ink tubes 41 can be arranged in the same juxtaposed relationship, with the ink tube 41 disposed farthest upstream in the paper-conveying direction at the carriage 38 positioned on top at the fixing clip 36.
A flat cable 85 transfers recording signals and the like from a main circuit board constituting a controller 64 (see
The flat cable 85 is flexible and bends in response to the reciprocation of the carriage 38. As shown in
A restricting wall 37 is provided on the front surface of the printer section 2 extending in the width direction (left-to-right direction in
The fixing clip 36 is disposed near the widthwise center of the printer section 2. The fixing clip 36 fixes the ink tubes 41 so that the ink tubes 41 extend toward the restricting wall 37. More specifically, the vertical surface of the restricting wall 37 and the direction in which the ink tubes 41 extend from the fixing clip 36 forms an obtuse angle less than 180 degrees in a plan view. The ink tubes 41 are flexible, but have a degree of stiffness (flexural rigidity). Hence, the ink tubes 41 press against the surface of the restricting wall 37 when extending at an angle from the fixing clip 36 to the restricting wall 37. Consequently, the range in which the ink tubes 41 follow the restricting wall 37 expands within the reciprocating range of the carriage 38, thereby reducing the area in the section from the curved section of the ink tubes 41 to the carriage 38 that expands toward the carriage 38.
The fixing clip 86 is disposed near the widthwise center of the printer section 2 further inside than the fixing clip 36. The fixing clip 86 fixes the flat cable 85 so that the flat cable 85 expands toward the restricting wall 37. Hence, the vertical surface of the restricting wall 37 and the direction in which the flat cable 85 extends from the fixing clip 86 forms an obtuse angle smaller than 180 degrees in a plan view. The flat cable 85 is flexible, but has a degree of stiffness (flexural rigidity). Hence, the flat cable 85 presses against the surface of the restricting wall 37 when extending at an angle from the fixing clip 86 to the restricting wall 37. Consequently, the range in which the flat cable 85 follows the restricting wall 37 expands within the reciprocating range of the carriage 38, thereby reducing the area in the section from the curved section of the flat cable 85 to the carriage 38 that expands toward the carriage 38.
As shown in
As shown in
While the cavity 55 is provided for each nozzle 53, a single manifold 56 is formed along the plurality of cavities 55. The manifold 56 is provided for each of the colors cyan, magenta, yellow, and black. A buffer tank 57 is provided upstream of the cavity 55. One buffer tank 57 is provided for each color cyan, magenta, yellow, and black. An ink supply opening 58 is formed in a side wall of the buffer tank 57 for supplying ink from the ink tubes 41 into the buffer tank 57. By temporarily storing ink in the buffer tank 57, air bubbles generated in the ink in the ink tubes 41 are captured and prevented from entering the cavity 55 and manifold 56. The pump mechanism removes air bubbles captured in the buffer tank 57 by suction via an air bubble outlet 59. Ink supplied from the buffer tank 57 to the manifold 56 is distributed by the manifold 56 to each of the cavities 55.
This construction forms an ink channel by which ink of the respective color supplied from the respective ink cartridge via the ink tube 41 flows to the cavity 55 via the buffer tank 57 and manifold 56. In this way, ink of each color cyan, magenta, yellow, and black supplied via these ink channels is subsequently ejected from the nozzle 53 onto recording paper as ink droplets when the piezoelectric element 54 deforms.
As shown in
Since the spur rollers 63 press against paper that has been printed, the roller surface of the spur rollers 63 is shaped like a spur with alternating protruding and depressed parts so as to not degrade the image recorded on the paper. The spur rollers 63 are capable of sliding in a direction for contacting or separating from the discharge rollers 62. A coil spring urges the spur rollers 63 to press against the discharge rollers 62. When recording paper becomes interposed between the discharge rollers 62 and spur rollers 63, the spur rollers 63 recede against the urging force of the coil spring by a distance equivalent to the thickness of the recording paper, while pressing the recording paper against the discharge rollers 62. In this way, the rotational force of the discharge rollers 62 is reliably transmitted to the recording paper. The pinch roller is similarly provided against the conveying roller 60, pressing the recording paper against the conveying roller 60 so that the rotational force of the conveying roller 60 is reliably transmitted to the recording paper.
A registration sensor 95 is disposed on the paper-conveying path 23 upstream of the conveying roller 60. The registration sensor 95 includes a probe shown in
In addition to feeding recording paper from the feeding tray 20, the linefeed motor 71 in the multifunction device 1 of the preferred embodiment functions to convey recording paper to a position over the platen 42 and to discharge recording paper onto the discharge tray 21 after recording has completed. In other words, the linefeed motor 71 drives the conveying roller 60 (see
The controller 64 controls the overall operations of the multifunction device 1, including not only the scanner section 3, but also the printer section 2. The controller 64 is configured of a main circuit board connected to the flat cable 85. Since the structure of the scanner section 3 is not important in the present invention, a detailed description of this structure has been omitted.
As shown in
The ROM 66 stores programs and the like for controlling various operations of the multifunction device 1. The RAM 67 functions as a storage area or a work area for temporarily saving various data used by the CPU 65 in executing the programs. The EEPROM 68 stores settings, flags, and the like that must be preserved when the power is turned off.
On a command from the CPU 65, the ASIC 70 generates a phase excitation signal and the like for conducting electricity to the linefeed motor 71. The signal is applied to a drive circuit 72 of the linefeed motor 71. By supplying a drive signal to the linefeed motor 71 via the drive circuit 72, the ASIC 70 can control the rotation of the linefeed motor 71.
The drive circuit 72 drives the linefeed motor 71, which is connected to the feeding roller 25, conveying roller 60, discharge rollers 62, and purge mechanism 51. Upon receiving an output signal from the ASIC 70, the drive circuit 72 generates an electric signal for rotating the linefeed motor 71. When the linefeed motor 71 rotates, the rotational force of the linefeed motor 71 is transferred to the feeding roller 25, conveying roller 60, discharge rollers 62, and purge mechanism 51 via a drive mechanism well known in the art that includes gears, drive shafts, and the like. In other words, in addition to feeding recording paper from the feeding tray 20, the linefeed motor 71 in the multifunction device 1 of the preferred embodiment functions to convey recording paper to a position over the platen 42 and to discharge recording paper onto the discharge tray 21 after recording is completed.
Similarly, upon receiving a command from the CPU 65, the ASIC 70 generates a phase excitation signal and the like for supplying electricity to the carriage motor 73 and applies this signal to a drive circuit 74 of the carriage motor 73. By supplying a drive signal to the carriage motor 73 via the drive circuit 74, the ASIC 70 can control the rotation of the carriage motor 73.
The drive circuit 74 functions to drive the carriage motor 73. Upon receiving an output signal from the ASIC 70, the drive circuit 74 generates an electric signal for rotating the carriage motor 73. When the carriage motor 73 rotates, the rotational force of the carriage motor 73 is transferred to the carriage 38 via the belt drive mechanism 46, thereby scanning the carriage 38 in a reciprocating motion. In this way, the controller 64 can control the reciprocation of the carriage 38.
A drive circuit 75 is provided for driving the inkjet recording head 39 at a prescribed timing. The ASIC 70 generates and outputs a signal to the drive circuit 75 based on a drive control procedure received from the CPU 65. The drive circuit 75 drives the inkjet recording head 39 based on the output signal received from the ASIC 70. The drive circuit 75 is mounted in the head control circuit board. When an output signal is transferred from the main circuit board constituting the controller 64 to the head control circuit board via the flat cable 85, the drive circuit 75 drives the inkjet recording head 39 to selectively eject ink of each color onto the recording paper at a prescribed timing.
The ASIC 70 is also connected to the rotary encoder 76 for detecting the rotated amount of the conveying roller 60, the linear encoder 77 for detecting the position of the carriage 38, and the registration sensor 95 for detecting the leading and trailing edges of the recording paper. When the power of the multifunction device 1 is turned on, the carriage 38 is moved to one end of the guide rails 43 and 44 and the detection position of the linear encoder 77 is initialized. When the carriage 38 moves from this initial position over the guide rails 43 and 44, the optical sensor 35 provided on the carriage 38 detects the pattern on the encoder strip 50 and outputs a pulse signal based on these detections The controller 64 determines the distance that the carriage 38 has moved based on the number of pulse signals. According to this detected movement, the controller 64 controls the rotation of the carriage motor 73 in order to control the reciprocating motion of the carriage 38. The controller 64 also determines the leading and trailing edge positions of recording paper based on a signal outputted from the registration sensor 95 and an encoder amount detected by the rotary encoder 76. When the leading edge of a sheet of recording paper arrives at a prescribed position on the platen 42, the controller 64 begins controlling the rotation of the linefeed motor 71 for conveying the recording paper intermittently at prescribed linefeed widths. The linefeed width is set based on a resolution and the like inputted as recording conditions.
The ASIC 70 is also connected to the scanner section 3; the control panel 4 for specifying operations of the multifunction device 1; the slot section 5 in which various small memory cards can be inserted; a parallel interface 78, a USB interface 79, and the like for exchanging data with a personal computer or other external device via a parallel cable or USB cable; and a NCU (network control unit) 80 and a modem 81 for implementing a facsimile function.
As described above, the platen 42 is disposed in opposition to the inkjet recording head 39 (below the inkjet recording head 39 in
The platen 42 includes a frame 100; first fixed ribs 102 and second fixed ribs 103 disposed on the frame 100; the movable support piece 88 slidably provided on the frame 100; and the interlock mechanism 105 described later for sliding the movable support piece 88.
The frame 100 is formed of a synthetic resin or steel plate and constitutes the frame of the platen 42. The cross-section of the frame 100 is shaped similar to the letter C. Brackets 106 and 107 are disposed one on either end of the frame 100 in the main scanning direction. The brackets 106 and 107 are integrally formed with the frame 100. The frame 100 is fixed to the multifunction device 1 via the brackets 106 and 107.
A drive mechanism mounting section 108 is disposed on one end of the frame 100 (the near side in
The first fixed ribs 102 and second fixed ribs 103 are provided on the top surface 109 of the frame 100. More specifically, the first fixed ribs 102 are provided on an upstream end of the top surface 109 in the paper-conveying direction and protrude upward toward the inkjet recording head 39 The second fixed ribs 103 are provided on the downstream side of the top surface 109 in the paper-conveying direction and protrude upward. As shown in
In the preferred embodiment, the first fixed ribs 102 are provided on the multifunction device 109 and juxtaposed in the main scanning direction. Similarly, the second fixed ribs 103 are provided on the top surface 109 and juxtaposed in the main scanning direction. With this construction, a groove 116 is formed between the first fixed ribs 102 and second fixed ribs 103. As shown in
In the preferred embodiment, the first fixed ribs 102 and second fixed ribs 103 oppose each other in the paper-conveying direction (the direction of the arrow 89) with the groove 116 interposed therebetween, as shown in
A plurality of slits 119 are formed in the top surface 109 of the frame 100. The slits 119 extend from the upstream end to the downstream end of the top surface 109 in the paper-conveying direction and are juxtaposed in the main scanning direction. Each slit 119 extends from the region between neighboring first fixed ribs 102 to the region between neighboring second fixed ribs 103. The movable support piece 88 is fitted into the slits 119 and protrudes upward therefrom.
As shown in
The ribs 121 are provided on the top surface of the base 120 and are formed integrally with the base 120 Each of the ribs 121 is formed in a triangular shape. In the preferred embodiment, the ribs 121 are erected on the top surface of the base 120 and are juxtaposed at prescribed intervals in the main scanning direction (the direction indicated by the arrow 87 in
The ribs 121 constituting the movable support piece 88 are formed in a triangular shape, as described above. More specifically, a beveling process similar to that performed on the first fixed ribs 102 and second fixed ribs 103 is performed on corners 122 and 123 of the ribs 121, configuring sloped surfaces that slope relative to the paper-conveying direction. In the preferred embodiment, the sloped surfaces are formed on both of the corners 122 and 123 of the ribs 121 in the paper-conveying direction. However, it is possible to form the sloped surface on only the upstream corner 122.
As described above, the interlock mechanism 105 slides the movable support piece 88 in the paper-conveying direction. The interlock mechanism 105 is interposed between a discharge roller shaft 92 and the movable support piece 88 for interlocking the movable support piece 88 with the discharge roller shaft 92. The movable support piece 88 moves along with the movement of the recording paper as the recording paper is conveyed over the platen 42 so as to support the edges of the recording paper at all times. Specifically, when the recording paper has been conveyed to an upstream edge 94 of the frame 100 in the paper-conveying direction (see
As shown in
As shown in FIGS. 12 and 1.3, the rotating plate 125 is disc-shaped and formed of synthetic resin or metal. The rotating plate 125 includes a circular rotating plate part 141, and a cylindrical shaft 127 erected from a center region in the top surface of the rotating plate part 141. The cylindrical shaft 127 is rotatably supported on the frame 100 of the platen 42. As one example, a center rotational shaft (not shown) may be erected in the frame 100. In this case, the center rotational shaft extends in a direction orthogonal to both the main scanning direction and the paper-conveying direction. The cylindrical shaft 127 is then fitted into the center rotational shaft so as to be capable of rotating freely. Alternatively, the center rotational shaft of the rotating plate 125 may be configured by fitting the cylindrical shaft 127 into the frame 100 directly. In addition, ribs 128 and 129 are erected from the top surface of the rotating plate 125. The rib 129 is formed with a rectangular cross-section and has an overall circular shape centered on the cylindrical shaft 127. The rib 128 also has a rectangular cross-section and an overall circular shape centered on the cylindrical shaft 127 and surrounding the rib 129.
The rotating plate 125 is driven in a forward rotation or a reverse rotation through the drive transmitting mechanism 124 described later, where the forward rotation is the direction indicated by the arrow 130. As shown in
As shown in
As shown in
By fitting the base end 146 of the lever member 126 into the guide groove 143 of the rotating plate 125, the base end 146 can only be displaced in the paper-conveying direction. However, the distal end 145 of the lever member 126 is fitted into the base 120 and can therefore only be displaced in the paper-conveying direction. Hence, by rotating the rotating plate 125, the base end 146 of the lever member 126 is guided along the guide groove 143, while the lever member 126 pivots about the center part 147. As a result, the distal end 145 of the lever member 126 pivots about the center part 147. Since the distal end 145 can be displaced in the paper-conveying direction, the base 120 slides in the paper-conveying direction as the distal end 145 pivots.
Here, the displacement of the distal end 145 is a prescribed multiple of the displacement in the base end 146. This multiple more specifically corresponds to the ratio of the distance from the center part 147 to the distal end 145 and the distance from the center part 147 to the base end 146. Therefore, the displacement of the distal end 145 amplifies the displacement in the base end 146 by the prescribed multiple. In other words, the lever member 126 converts the rotation of the rotating plate 125 to displacement of the base 120 in the paper-conveying direction according to the prescribed ratio.
As shown in
While not illustrated in
In the preferred embodiment, a rotation restricting device 156 is provided for restricting rotation of the rotating plate 125. As shown in
The locking member 139 is formed in the shape of a crankshaft. A base end of the locking member 139 is rotatably supported on a support shaft 159. Accordingly, the locking member 139 can rotate about the support shaft 159 in an elevating direction indicated by the arrow 160. An engaging pawl 161 is provided on the distal end of the locking member 139. The engaging pawl 161 is formed in a wedge shape for fitting into the V groove 131 of the rotating plate 125.
Since the locking member 139 can pivot about the support shaft 159, the orientation of the locking member 139 can be changed between a rotation restricting orientation laying down on the rotating plate 125 side with the engaging pawl 161 fitted into the V groove 131, and a rotation allowing orientation angled upward above the rotating plate 125 with the engaging pawl 161 removed from the V groove 131. However, the coil spring 157 is provided for constantly urging the locking member 139 into the rotation restricting orientation.
Therefore, when the engaging pawl 161 is fitted into the V groove 131, the forward restricting surface 132 (see
The locking member 140 is formed in the shape of a quadratic prism. While not shown in
The contact member 158 is coupled to the base end of the locking member 139. Accordingly, the contact member 158 can rotate about the support shaft 159 together with the locking member 139. A distal end 164 of the contact member 158 extends upward so that the carriage 38 supporting the inkjet recording head 39 (see
Next, an overview of the image-recording operation performed with the multifunction device 1 according to the preferred embodiment will be described.
In the multifunction device 1 according to the preferred embodiment, the user operates the control panel 4 (see
In order to feed recording paper accommodated in the feeding tray 20 to the paper-conveying path 23 for image recording, the controller 64 drives the linefeed motor 71 to rotate the feeding roller 25. During this feeding operation, the linefeed motor 71 is driven in a reverse rotation. The transmitted drive force from the linefeed motor 71 rotates the feeding roller 25 in a direction for feeding the recording paper, while rotating the conveying roller 60 and discharge rollers 62 in a direction opposite the paper-conveying direction. As the recording paper fed from the feeding tray 20 is conveyed along the paper-conveying path 23, the recording paper is inverted vertically by the U-shaped paper-conveying path 23. The leading edge of the recording paper contacts the registration sensor 95 and subsequently contacts the conveying roller 60 and pinch roller. Since the conveying roller 60 is rotating in a direction opposite the paper-conveying direction, the recording paper is registered while the leading edge is in contact with the conveying roller 60 and the pinch roller A point 174 in
As the discharge rollers 62 are driven to rotate in the direction opposite the paper-conveying direction by the reverse rotation of the linefeed motor 71, this rotation is transmitted to the rotating plate 125 via the drive transmitting mechanism 124. However, rotation of the rotating plate 125 is restricted when the rotating plate 125 is in the initial position, that is, when the locking member 140 is engaged in the V groove 134. Hence, only the rotating support member 90 is allowed to rotate in reverse by the torque limiter 148 as the reverse rotation of the rotating plate 125 is halted. However, if the rotating plate 125 is not in the initial position and, hence, the locking member 140 is not engaged with the V groove 134, then the rotation of the discharge rollers 62 is transmitted to the rotating plate 125 via the drive transmitting mechanism 124, causing the rotating plate 125 to rotate in reverse. Subsequently, the rotating plate 125 rotates in reverse until reaching the initial position, at which time the locking member 140 engages with the V groove 134 and restricts further rotation of the rotating plate 125 in reverse so that only the discharge roller shaft 92 is rotating in reverse. This operation for driving the linefeed motor 71 in reverse is performed to move the rotating plate 125 to the initial position and may be performed when the power to the multifunction device 1 is turned on or after an error is resolved. Further, by moving the rotating plate 125 to the initial position, the locking member 139 engages with the V groove 131 to restrict forward rotation of the rotating plate 125.
During borderless recording, the movable support piece 88 slides along with the conveyance of the recording paper. More specifically, when the recording paper is set in the initial position 174 (see
After the leading edge of the recording paper is registered by the conveying roller 60, as described above, the linefeed motor 71 is driven intermittently in a forward rotation for conveying the recording paper to recording positions over the platen 42, as indicated by the line 168 in
As shown in
Initially, the movable support piece 88 is positioned at an intermediate between the first fixed ribs 102 and the second fixed ribs 103 (see
Subsequently, image recording is performed on the recording paper by repeatedly and alternately ejecting ink droplets from the inkjet recording head 39 while the carriage 38 reciprocates, and conveying the recording paper a prescribed linefeed corresponding to the set resolution. Specifically, the linefeed motor 71 is driven intermittently in a forward rotation, as indicated by the line 168 in
When the rotating plate 125 rotates as described above, the engaging pawl 161 slides over the top surface 137 of the rib 128, as shown in
In this state, the recording paper is conveyed intermittently as prescribed linefeed widths, while recording continues, as shown in
When the carriage 38 presses against the contact member 158 in the main scanning direction, the locking member 139 rotates about the support shaft 159 and disengages the engaging pawl 161 from the rotating plate 125, as described above. Therefore, the rotating plate 125 can move in a forward rotation (clockwise about the cylindrical shaft 127). As a result, the movable support piece 88 is displaced as indicated by the line 170 in
After the rotating plate 125 completes one rotation, the engaging pawl 161 is again fitted into the V groove 131 of the rotating plate 125 by the urging force of the coil spring 157, thereby restricting forward rotation of the rotating plate 125 and returning the movable support piece 88, rotating plate 125, and lever member 126 to their initial positions. Once the image-recording operation is completed, the linefeed motor 71 is driven continuously in the forward rotation for discharging the recording paper onto the discharge tray 21. While the rotation of the rotating plate 125 is restricted at this time, the torque limiter 148 allows the discharge rollers 62 to rotate smoothly.
However, if the user sets the image-forming format to border recording by operating the control panel 4, the carriage 38 is not moved into contact with the contact member 158 Therefore, the movable support piece 88 does not slide as described above, but remains halted in the initial position. When performing border recording, it is still preferable to rotate the linefeed motor 71 in reverse prior to feeding the recording paper In this case, even if the locking member 140 is not engaged with the rotating plate 125, the rotating plate 125 rotates in reverse as described above until the locking member 140 is fitted into the V groove 134 of the rotating plate 125, thereby reliably initializing the locking member 140 of the rotating plate 125.
In the multifunction device 1 according to the preferred embodiment, the platen 42 supports the recording paper as the recording paper is conveyed over the platen 42, and the inkjet recording head 39 records an image on the recording paper by ejecting ink droplets as the carriage 38 slides in the main scanning direction. The recording paper is conveyed in the paper-conveying direction during the image-recording operation, while the movable support piece 88 slides in the paper-conveying direction while supporting the recording paper, as shown in
As shown in
Since the lever member 126 is engaged in the guide groove 143 of the rotating plate 125, as shown in
Moreover, since the movable support piece 88 is driven by the linefeed motor 71, the movable support piece 88 can slide more smoothly. Accordingly, images of higher quality can be recorded on the paper.
In the preferred embodiment, the movable support piece 88 moves in association with the discharge roller shaft 92, which is driven by the linefeed motor 71. In most inkjet recording devices, the conveying roller 60 is disposed near the inkjet recording head 39, and the drive transmitting mechanism 83 for transmitting a driving force from the conveying roller 60 to the discharge rollers 62, the purge mechanism 51, and the like must maintain a prescribed geometrical relationship with the conveying roller 60 and inkjet recording head 39. Hence, if the movable support piece 88 were to receive a driving force from the conveying roller 60 disposed near the inkjet recording head 39, the image-recording unit 24 would require a complex structure that would be difficult to design due to the geometrical relationship. However, in the multifunction device 1 according to the preferred embodiment, the movable support piece 88 obtains a drive force from the discharge rollers 62 disposed in a region of the multifunction device 1 having more available space, thereby simplifying the structure of the image-recording unit 24 and enabling a more compact design for the multifunction device 1.
By employing a disc-shaped rotating plate 125 as the means for driving the movable support piece 88 in the preferred embodiment, the structure for driving the movable support piece 88 is extremely simple, and the structure for rotating the rotating plate 125 can be achieved with a compact design. Accordingly, the image-recording unit 24 can be made even more compact.
Further, by forming the guide groove 143 in the rotating plate 125 in the shape described above, the movable support piece 88 initially slides upstream in the paper-conveying direction to meet the recording paper and subsequently slides downstream as the recording paper is conveyed, as shown in
Particularly, since the guide groove 143 is shaped like an Archimedean spiral in the preferred embodiment, the distal end 145 of the lever member 126 moves radially from the center of the rotating plate 125 as the rotating plate 125 rotates (see
If the guide groove 143 were not formed in an Archimedean spiral, the rotating plate 125 may rotate at a constant speed unrelated from the linefeed widths of the recording paper. While this configuration does not produce any complications immediately, the constant speed of the rotating plate 125 may cause the movable support piece 88 to pass the conveyed recording paper. If there is a danger of this happening, it is possible to halt the movable support piece 88 at a ratio of once for each prescribed number of linefeeds.
As shown in
The multifunction device 1 according to the preferred embodiment also has the following operations and effects.
The edge of the recording paper conveyed over the first fixed rib 102 passes above the groove 116. At this time, the movable support piece 88 slides together with the recording paper as the recording paper is conveyed so as to support the edge of the recording paper at all times and prevent the edge from entering the groove 116. Accordingly, the movable support piece 88 can maintain a fixed distance between the recording paper and the inkjet recording head 39.
In the preferred embodiment, the recording paper conveyed over the platen 42 is first supported on the first fixed ribs 102, and subsequently supported on the second fixed ribs 103 after passing over the groove 116. When performing borderless recording in particular, the groove 116 can receive ink droplets ejected from the inkjet recording head 39 beyond the edge of the recording paper. The bottom of the groove 116 may be lined with an ink absorbing material such as a sheet-like sponge material capable of reliably absorbing ink droplets that reach the groove 116.
As described above, since the recording paper covers the movable support piece 88 when the movable support piece 88 is supporting the edge of the paper, ink droplets ejected onto the recording paper do not become deposited on the movable support piece 88. Hence, when recording on a plurality of sheets continuously, the bottom surface of subsequent sheets of recording paper do not become stained with ink deposited when recording on the preceding sheets.
Further, since the movable support piece 88 supports the recording paper, the groove 116 can be formed with a large width dimension 117, making it possible to increase the size of the inkjet recording head 39 because the groove 116 can cover the entire ink ejection range 118 of a large inkjet recording head 39. This construction makes it possible to perform borderless recording at a high speed.
The first fixed ribs 102, second fixed ribs 103, and ribs 121 functioning to support the recording paper are particularly advantageous because they provide an extremely simple structure for supporting the recording paper and they reduce the area of contact between the support members and the recording paper. Consequently, this construction reduces resistance to the recording paper, enabling the recording paper to be conveyed more smoothly.
In the preferred embodiment, the width dimension 117 of the groove 116 (see
Put another way, if the width dimension 117 of the groove 116 were narrower than the ink ejection range 118 of the inkjet recording head 39, then it would be necessary to eject ink droplets only from nozzles 53 on the upstream side of the inkjet recording head 39 when performing borderless recording on the leading edge portion of the recording paper, and subsequently to eject ink droplets from sequential rows of nozzles 53 on the downstream side as the recording paper is conveyed, thereby requiring a complex process for controlling the inkjet recording head 39. In contrast, the multifunction device 1 of the preferred embodiment can eliminate this complex control process. As described above, the multifunction device 1 can perform borderless recording on the edge of the recording paper by ejecting ink droplets from all nozzles 53. Hence, borderless recording can be performed at a high speed, without implementing a complex control process for ejecting ink droplets from the nozzles 53.
Further, the cross-sectional shape of the nozzles 53 is not always perfectly round and occasionally fine particles of foreign matter become deposited inside the nozzles 53. These factors sometimes contribute to an ink droplet trajectory that is less than straight from the nozzles 53. However, since the width dimension 117 of the groove 116 is set wider than the ink ejection range 118 of the inkjet recording head 39 in the preferred embodiment, the ink droplets do not land outside of the groove 116 even in this case. Hence, this construction reliably prevents ink from staining the underside of recording paper.
By using the first fixed ribs 102, second fixed ribs 103, and ribs 121 for supporting the recording paper, the structure of the components used to support the recording paper is very simple, and the surface area of contact between the ribs and the recording paper is small. Reducing the surface area of contact with the recording paper reduces the resistance to the recording paper, enabling the recording paper to be conveyed more smoothly. Further, sloped surfaces are formed on the corner 122 and corner 123 of the ribs 121 through a process of beveling the corner 122 and corner 123. Hence, when the edge of the recording paper passing over the first fixed ribs 102 contacts the corners 122 of the ribs 121, the edge of the recording paper is guided smoothly onto the movable support piece 88. Hence, the movable support piece 88 does not interfere with the smooth conveyance of the recording paper. As described above, the bevel process is also performed on the corners of the first fixed ribs 102 and second fixed ribs 103, forming sloped surfaces in these areas. Hence, when the edge of a sheet of recording paper contacts the corners of the first fixed ribs 102 and second fixed ribs 103, the sloped surfaces facilitate the smooth conveyance of the recording paper.
As shown in
In the preferred embodiment, the locking member 139 is normally engaged with the rotating plate 125, as shown in
Next, a variation of the preferred embodiment will be described.
In the preferred embodiment described above, the movable support piece 88 is provided with the lever member 126, as shown in
More specifically, an engaging surface 142 (“back surface” in the preferred embodiment) of the rotating plate 125 is substantially orthogonal to the top surface 109 of the platen 42. The engaging pin 175 protrudes from an end surface of the movable support piece 176 and fits into the guide groove 143 formed in the engaging surface 142 of the rotating plate 125. The engaging pin 175 is capable of sliding within the guide groove 143. Hence, rotation of the rotating plate 125 slides the movable support piece 176 via the engaging pin 175 in the variation of the embodiment so that the ribs 121 can reliably support recording paper conveyed over the platen 42. Moreover, since the movable support piece 176 is slid via the engaging pin 175, the interlock mechanism 105 functioning to drive the movable support piece 176 can be achieved with a simple structure.
Next, a second embodiment of the present invention will be described.
As in the first embodiment described above, the platen 42 in the second embodiment is disposed opposite the inkjet recording head 39 (below the inkjet recording head 39 in
The platen 42 includes the frame 100; the first fixed ribs 102 and second fixed ribs 103 disposed on the frame 100; the movable support piece 88 slidably provided on the frame 100; and the interlock mechanism 105 for sliding the movable support piece 88.
The frame 100 is formed of a synthetic resin or steel plate, for example, and constitutes the frame of the platen 42. The cross-section of the frame 100 is shaped similar to the letter C. The bracket 106 and bracket 107 are disposed one on the base end and distal end of the frame 100. The bracket 106 and bracket 107 are integrally formed with the frame 100. The frame 100 is fixed to the multifunction device 1 via the bracket 106 and bracket 107.
The drive mechanism mounting section 108 is disposed on the base end of the frame 100. As shown in
The first fixed ribs 102 and second fixed ribs 103 are provided on the top surface 109 of the frame 100. More specifically, the first fixed ribs 102 are provided on an upstream end of the top surface 109 in the paper-conveying direction and protrude upward toward the inkjet recording head 39. Similarly, the second fixed ribs 103 are provided on the downstream side of the top surface 109 and protrude upward. As shown in
In the preferred embodiment, the first fixed ribs 102 are provided on the top surface 109 and juxtaposed in the main scanning direction. Similarly, the second fixed ribs 103 are provided on the top surface 109 and juxtaposed in the main scanning direction. With this construction, the groove 116 is formed between the first fixed ribs 102 and second fixed ribs 103. As shown in
As shown in
A plurality of slits 119 is formed on the top surface 109 of the frame 100. As shown in
As shown in
The ribs 121 are provided on the top surface of the base 120 and are formed integrally with the same. Each of the ribs 121 is formed in a rectangular shape and protrudes upward from the top surface 109 of the frame 100 through the slits 119, as shown in
A beveling process similar to that performed on the first fixed ribs 102 and second fixed ribs 103 is performed on the corners 122 and 123 of the ribs 121, forming a pair of sloped surfaces on each rib 121. In the preferred embodiment, the sloped surfaces are formed on both of the corner 122 and corner 123 of each rib 121. However, it is possible to form the sloped surface on only the upstream corner 122.
As described above, the interlock mechanism 105 slides the movable support piece 88 in the paper-conveying direction. As shown in
The input member 224 is substantially L-shaped, as shown in
The rotating plate 225 is disc-shaped and capable of rotating on a rotational shaft 234. The rotational shaft 234 is fixed to the frame 100 (more specifically, the lower plate 178) and inserted through the center of the rotating plate 225. A plurality of teeth 235 is formed continuously around the periphery of the rotating plate 225. The teeth 235 engage with the engaging pawl 231 of the input member 224. Hence, when the input member 224 is slid in the direction of the arrow 233, as described above, the rotating plate 225 rotates clockwise in
The pivoting member 226 includes a main body 237 configured of a long slender plate, an engaging pin 238 disposed on the base end 146 of the main body 237, and an engaging rod 239 disposed on the distal end 145 of the main body 237. The pivoting member 226 is configured of a synthetic resin or metal. The main body 237 is rotatably supported on a pivot shaft 240. The pivot shaft 240 is fixed to the lower plate 178 of the drive mechanism mounting section 108 and inserted through a center portion of the main body 237. The engaging pin 238 protrudes upward from the main body 237 (see
Therefore, when the main body 237 pivots as described above so that the engaging rod 239 moves in an arc about the pivot shaft 240, the base 120 slides in the conveying direction as the engaging rod 239 slides along the elongated hole 241 in the main scanning direction. As described above, both ends of the base 120 in the main scanning direction are slidably supported on the frame 100. Accordingly, the base 120 slides smoothly in the paper-conveying direction (indicated the arrow 101 in
The rotation-restricting member 227 employs an engaging rod for engaging with the rotating plate 225. As shown in
The rotation-restricting member 227 is also provided with a contact pin 245. The contact pin 245 protrudes downward from the rotation-restricting member 227 (see
In the preferred embodiment, the engaging pin 238 is engaged with the guide groove 143 at a prescribed position in
When the inkjet recording head 39 reciprocates in the main scanning direction, the carriage 38 intermittently presses against the input member 224, causing the rotating plate 125 to rotate clockwise in
The movable support piece 88 is initially positioned between the first fixed ribs 102 and second fixed ribs 103. However, when a sheet of recording paper 246 is conveyed to the upstream edge 94 of the frame 100, as shown in
As described in the first embodiment, to perform an image-recording operation the controller 64 drives the linefeed motor 71 in order to rotate the feeding roller 25. The feeding roller 25 feeds a sheet of recording paper stacked in the feeding tray 20 onto the paper-conveying path 23. When feeding a sheet of recording paper, the linefeed motor 71 is driven in a reverse rotation. The drive force of the linefeed motor 71 is transferred to the feeding roller 25 and rotates the feeding roller 25 in a direction for feeding the recording paper. The driving force is also transferred to the conveying roller 60 and discharge rollers 62 for rotating the conveying roller 60 and discharge rollers 62 in the direction opposite the paper-conveying direction. Recording paper conveyed from the feeding tray 20 along the paper-conveying path 23 is guided by the paper-conveying path 23 along a U-shaped path that curves upward and back in the opposite direction. As the recording paper is conveyed farther, the leading edge of the paper first contacts the registration sensor 95 and subsequently contacts the conveying roller 60 and the pinch roller. Since the conveying roller 60 is rotating in a direction opposite the paper-conveying direction, the recording paper is registered by contacting the conveying roller 60 and the pinch roller. The registration position is indicated by the reference numeral 174 in
When performing borderless recording, the movable support piece 88 is slid along with the conveyance of the recording paper. More specifically, when the recording paper is at the registration position 174, the movable support piece 88 is positioned in the center of the platen 42, as described above. At this time, the base end 146 of the pivoting member 226 is disposed in a prescribed position of the guide groove 143 (an initial position similar to the position indicated by the reference numeral 165 in
After the leading edge of the recording paper 246 has been registered on the conveying roller 60, the linefeed motor 71 is driven intermittently, as indicated by the line 168 in
When the carriage 38 slides against the input member 224, the rotating plate 225 rotates clockwise in
Thereafter, each time the carriage 38 slides into the input member 224 during the image-recording operation, the rotating plate 225 is rotated clockwise in
After the rotational angle of the rotating plate 125 has reached 180° and the movable support piece 88 has moved between the first fixed ribs 102 and second fixed ribs 103, the movable support piece 88 is maintained in this position while the recording paper 246 continues to be conveyed in the paper-conveying direction and the image-recording operation continues to be performed, as shown in
When the recording paper 246 has been conveyed far enough for the trailing edge to reach the movable support piece 88, as shown in
When the recording paper 246 is discharged, the carriage 38 slides the input member 224 to a prescribed restriction release position. Here, the carriage motor is driven to slide the carriage 38 to a prescribed position for moving the input member 224 to the restriction release position. More specifically, the input member 224 is slid in the direction of the arrow 233 shown in
In the multifunction device 1 of the preferred embodiment, the platen 42 supports the recording paper 246 as the recording paper 246 is conveyed over the top thereof, and an image is recorded on the recording paper 246 supported on the platen 42 with ink droplets ejected from the inkjet recording head 39 as the inkjet recording head 39 reciprocates. As the recording paper 246 is conveyed in the paper-conveying direction during the image-recording operation, the movable support piece 88 slides together with the recording paper 246 in the same direction while supporting the recording paper 246, as shown in
More specifically, the recording paper 246 is conveyed over the platen 42 while first supported by the first fixed ribs 102 and subsequently supported by the second fixed ribs 103 after passing over the groove 116. During borderless recording, the groove 116 can receive ink droplets ejected from the inkjet recording head 39 beyond the edges of the recording paper 246, thereby preventing such ink droplets from becoming deposited on the underside of subsequent sheets of the recording paper 246. As the recording paper 246 is conveyed over the groove 116, the movable support piece 88 slides in the paper-conveying direction along with the conveyance of the recording paper 246. In other words, the movable support piece 88 supports the recording paper 246 while sliding from the first position to the second position. Hence, the movable support piece 88 reliably supports the edges of the recording paper 246 at all times, preventing the recording paper 246 from entering the groove 116. As a result, the movable support piece 88 maintains a fixed distance between the recording paper 246 and the inkjet recording head 39, as described above, thereby achieving high-quality printing.
As shown in
In the preferred embodiment, the rotation-restricting member 227 functions to restrict rotation of the rotating plate 225. As shown in
By forming the guide groove 143 having the shape described above in the rotating plate 225 and rotating the rotating plate 225, the movable support piece 88 initially slides in the paper-conveying direction to meet the recording paper 246 and subsequently slides downstream together with the recording paper 246, as illustrated in
By forming the guide groove 143 in the shape of an Archimedean spiral in the preferred embodiment, the movable support piece 88 smoothly follows the conveyed recording paper 246 at a fixed speed as the rotating plate 225 rotates at a fixed speed. If the intermittent rotation of the rotating plate 225 corresponds to the linefeed width of the recording paper 246, the movable support piece 88 slides in synchronization with the conveyance of the recording paper 246, providing more reliable support for the recording paper 246. Accordingly, the movable support piece 88 can more accurately maintain a fixed distance between the inkjet recording head 39 and the recording paper 246.
In the preferred embodiment, a spring member is disposed between the upper plate 177 and lower plate 178. The spring member deforms as the rotating plate 225 rotates and stores a strain energy corresponding to the rotational angle of the rotating plate 225. After the recording paper 246 is discharged, the controller 64 controls the sliding movement of the inkjet recording head 39 so that the carriage 38 presses the input member 224 into the restriction release position, releasing the rotational restriction on the rotating plate 225. Consequently, the strain energy stored in the spring member is released, causing the rotating plate 225 to rotate counterclockwise until the movable support piece 88 returns to the initial position shown in
As shown in
By supporting the recording paper 246 with the movable support piece 88 in the preferred embodiment, the groove 116 may be formed with a large width dimension 117. Therefore, even if the size of the inkjet recording head 39 were increased, the groove 116 can cover the entire ink ejection range 118 of the inkjet recording head 39. As a result, borderless recording can be executed at a higher speed. It is particularly advantageous to configure the parts supporting the recording paper 246 with ribs since the structure is extremely simple. Further, the area of contact between the recording paper 246 and the first fixed ribs 102, second fixed ribs 103, and movable support piece 88 (ribs 121) is reduced, facilitating the smooth conveyance of the recording paper 246.
As in the first embodiment, the groove 116 according to the second embodiment has a wider width dimension 117 than the ink ejection range 118 of the inkjet recording head 39. Hence, even if ink droplets were ejected from all nozzles 53 in the inkjet recording head 39 when the recording paper 246 is not present over the platen 42, the groove 116 can receive all of the ink droplets. Therefore, when performing borderless recording, ink droplets can be ejected from all the nozzles 53 in the inkjet recording head 39 when recording on the edges of the recording paper 246. Hence, borderless recording can be performed at a high speed, since there is no need to perform a complex control process to control ink droplet ejection. Further, the cross-sectional shape of the nozzles 53 is not always perfectly round and occasionally fine foreign matter may become deposited inside the nozzles 53, causing the ink droplets to be ejected along a slightly slanted trajectory from the nozzles 53. However, the ink droplets do not impact the platen 42 outside the groove 116 since the width dimension 117 of the groove 116 is wider than the ink ejection range 118 of the inkjet recording head 39, thereby reliably preventing ink from staining the underside surface of the recording paper 246.
Further, sloped surfaces are formed on the ribs 121 by beveling the corners 122 and 123 thereof (see
In particular, the carriage motor 73 drives the carriage 38 to slide in a reciprocating motion so as to contact and slide the input member 224 (see
The movement of the movable support piece 88 described above is particularly necessary when performing borderless recording on the recording paper 246 and is not necessary when performing border recording. Since the movable support piece 88 is normally idle in the position shown in
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-375952 | Dec 2005 | JP | national |
| 2005-379602 | Dec 2005 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 5757407 | Rezanka | May 1998 | A |
| 5874979 | Ohyama | Feb 1999 | A |
| 5940092 | Kashimura et al. | Aug 1999 | A |
| 6179419 | Rasmussen et al. | Jan 2001 | B1 |
| 6239817 | Meyer | May 2001 | B1 |
| 6471351 | Ishikawa et al. | Oct 2002 | B1 |
| 6659603 | Kida et al. | Dec 2003 | B2 |
| 7086729 | Yoshikaie | Aug 2006 | B2 |
| 7093931 | Ishii et al. | Aug 2006 | B2 |
| 20020154203 | Tanaka | Oct 2002 | A1 |
| 20020191064 | Ishikawa et al. | Dec 2002 | A1 |
| 20050122384 | Kodama et al. | Jun 2005 | A1 |
| Number | Date | Country |
|---|---|---|
| H09-234916 | Sep 1997 | JP |
| 2000-118058 | Apr 2000 | JP |
| 2001-080145 | Mar 2001 | JP |
| 2002-307769 | Oct 2002 | JP |
| 2003-285487 | Oct 2003 | JP |
| 2005-007691 | Jan 2005 | JP |
| 2006-326990 | Dec 2006 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20070146463 A1 | Jun 2007 | US |
