JP4247613B2 - Medium separation apparatus and recording apparatus provided with the same - Google Patents

Description

  The present invention relates to a frontage regulating device in a medium separator. Furthermore, the present invention relates to a liquid ejecting apparatus such as an ink jet recording apparatus that includes the frontage restricting device and ejects a liquid such as ink from a head to eject the liquid onto an ejected medium.

  Here, the liquid ejecting apparatus uses an ink jet recording head, and is not limited to a recording apparatus such as a printer, a copier, and a facsimile machine that records ink on a recording medium by discharging ink from the recording head. It includes a device that ejects a liquid corresponding to the application from a liquid ejecting head corresponding to the recording head to an ejected medium corresponding to a recording medium and adheres the liquid to the ejected medium.

  In addition to the recording head, as a liquid ejecting head, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, and an electrode material (conductive paste) used for forming an electrode such as an organic EL display or a surface emitting display (FED) Examples thereof include an ejection head, a bioorganic matter ejection head used for biochip production, and a sample ejection head as a precision pipette.

  In a feeding device such as an ink jet printer, a medium separating device is provided in order to supply sheets as recording media one by one to a recording process (Patent Document 1). FIGS. 8A to 8G show the configuration and operation of a conventional medium separator. In FIG. 8A, reference numeral 101 denotes a feeding roller having a D shape in a side view, and a hopper swing cam 105 is provided on the rotation shaft 103 of the feeding roller 101. Below the feed roller 101, a retard roller 107 is provided for separating the multi-feed paper in cooperation with the feed roller 101. The retard roller 107 is always above by the action of a coil spring (not shown). Tend to be energized.

  The retard roller 107 is rotated by following the feeding roller 101 when feeding only one sheet, but is not driven by the feeding roller 101 when feeding two or more sheets. In addition, the lower sheet of the uppermost sheet is separated so as not to be fed to the recording apparatus side. A front opening regulating member 109 is formed on both sides of the retard roller 107, and a front opening is formed therebetween. A plurality of sheets are stacked on the hopper 111, and a cam follower 113 that cooperates with the hopper swing cam 105 is formed on the side of the hopper 111.

  When the feeding roller 101 rotates 60 degrees in the clockwise direction from the home position shown in FIG. 8-1 (a), the starting end of the feeding roller 101 contacts the retard roller 107 as shown in FIG. 8-1 (b). Then, the retard roller 107 starts to be pushed down. When the feeding roller 101 rotates by 70 degrees, the retard roller 107 is completely pushed down as shown in FIG. 8A, and the sheet P can be received between the feeding roller 101 and the feeding roller 101.

  When the feeding roller 101 rotates 74.13 degrees as shown in FIG. 8-2 (d), the leading edge of the sheet supplied from the hopper 111 comes into contact with the feeding roller 101, and feeding is started. When the feeding roller 101 rotates 80 degrees as shown in FIG. 8-2 (e) and the feeding roller 101 rotates 100 degrees as shown in FIG. 8-2 (f), the leading edge of the paper is fed. A nip point N between the feed roller 101 and the retard roller 107 is entered.

As shown in the enlarged view of FIG. 8-2 (f), on the side facing the feeding roller 101 of the frontage regulating member 109, a medium guide surface 115 is formed so as to form a convex curved surface on the upper side. The distance between the outer peripheral surface of the feed roller 101 and the medium guide surface 115 becomes narrower as it goes to. Thus, in the state shown in FIG. 8B, the leading edge of the paper P that has been multi-fed is shifted prior to paper separation by the action of the feeding roller 101 and the retard roller 107. Immediately thereafter, the sheet is separated by the action of the feeding roller 101 and the retard roller 107.
JP 2003-40476 A

  However, when a sheet having a relatively large coefficient of friction between sheets, such as a semi-gloss postcard, is fed, if the medium guide surface 115 is formed to have a convex curved surface on the upper side as in the conventional case, the sheet is double fed. Since the sheets are pressed together and the adhesion between the sheets is increased, there is a problem that the sheets are double fed to the recording process as they are without performing a desired sheet separation function.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a medium separating apparatus that can reliably separate sheets that have been multifed even with a sheet having a large friction coefficient or a sheet having high rigidity, and can supply only one recording medium to the recording process. It is in providing a frontage regulating device.

  In order to achieve the above object, a frontage regulating device in a medium separation device according to a first aspect of the present invention includes a feeding roller including an outer peripheral surface capable of sandwiching a recording medium and a flat portion, and the feeding roller. When there is one recording medium between the feeding roller and the opposite feeding roller, it rotates following the feeding roller and when there are two or more recording media between the feeding roller In a medium separating apparatus comprising a retard roller that acts to separate the recording medium below the uppermost recording medium so as not to be fed to the recording apparatus side, the medium separating path is in the middle of the medium guiding path to the feeding roller. A front opening restricting member extending oppositely from both the left and right sides of the front opening is provided at the front immediately before the nip point between the feeding roller and the retard roller, and the front opening restricting member is guided to the front opening. To restrict the number of recording media And a medium guide surface extending from the upper end of the contact restriction portion to the nip point side, and the medium guide surface is a side view when the feeding is performed. A substantially uniform gap is formed between the outer peripheral surface of the roller and the recording medium along the guide direction of the recording medium from the inlet portion toward the downstream of the feeding direction, and is formed on the start end side of the feeding roller. Is provided with a jump prevention device for preventing the recording medium from jumping into the gap.

  According to the first aspect of the present invention, the medium guide surface is between the outer peripheral surface of the feeding roller and the outer peripheral surface of the feeding roller as viewed from the side along the guiding direction of the recording medium from the inlet portion toward the downstream in the feeding direction. Since a substantially uniform gap is formed in the shape of the surface, the separation function by the retard roller reliably acts to prevent double feeding even when a recording medium having a large friction coefficient is fed.

  In addition, since a jump prevention device for preventing the recording medium from jumping into the gap is provided on the start end side of the feeding roller, the recording medium that is not completely returned to the hopper by the return action of the return lever is provided next time. When the hopper ascends for feeding, it can be prevented that the hopper jumps into the gap between the retard roller and the feeding roller due to vibration or warping of the paper. Thereby, the separation function by the retard roller can be surely exhibited, and double feeding can be effectively prevented.

Further, the frontage restricting device in the medium separating apparatus according to the second aspect of the present invention is the first aspect, wherein the recording medium jump-in prevention device is formed on the start end side of the outer peripheral surface of the feeding roller. It is an expansion part.
According to this aspect, when the feeding roller starts to push the retard roller, the expansion portion closes the gap between the retard roller and the feeding roller, so that the recording medium that is not returned into the hopper is in the gap between the gaps. It is possible to reliably prevent jumping.

According to a third aspect of the present invention, there is provided the frontage restricting device in the medium separating device according to the first aspect, wherein the recording medium jump-in preventing device includes flanges formed on both sides of the outer peripheral surface of the feeding roller. It is an expansion part formed in the start end side of a part, It is characterized by the above-mentioned.
According to this aspect, when the feeding roller starts to push in the retard roller, the expanding portion closes the gap formed on both sides of the gap between the retard roller and the feeding roller, and thus is not returned into the hopper. The medium cannot jump into the gap.

According to a fourth aspect of the present invention, there is provided a frontage regulating device according to any one of the first to third aspects, wherein the inflating portion is a first covered by the feeding roller and the retard roller. It is characterized by being positioned before the nip point of the recording medium in the rotational direction.
According to this aspect, the recording medium can be prevented from jumping in before the recording medium is nipped by the feeding roller and the retard roller, thereby preventing the recording medium from being fed.

  According to a fifth aspect of the present invention, there is provided a recording apparatus including the frontage regulating device in the medium separating apparatus according to any one of the first to fourth aspects. According to this aspect, since each recording medium is reliably fed from the feeding device to the recording unit, it is possible to provide a recording device with few failures that does not cause a jam or the like.

Further, the frontage restricting device in the medium separating apparatus according to the sixth aspect of the present invention is provided opposite to the feeding roller having an outer peripheral surface capable of sandwiching the ejected medium and a flat portion, and the feeding roller. When one medium to be ejected exists between the feeding roller and the feeding roller, it rotates following the feeding roller. When two or more sheets to be ejected exist between the feeding roller, the uppermost ejected medium And a retard roller that acts to separate the ejected medium below the medium so as not to be fed to the recording apparatus side, in the middle of the medium guide path to the feed roller, A front opening restricting member extending oppositely from both the left and right sides of the front opening is provided at a front end immediately before the nip point between the roller and the retard roller, and the front opening restricting member is a portion of the ejected medium guided to the front opening. The tip of the ejected medium to regulate the number of sheets And a medium guide surface extending from the upper end of the contact restriction portion toward the nip point, and the medium guide surface is in contact with the outer peripheral surface of the feeding roller in a side view. A substantially uniform gap is formed along the guide direction of the medium to be ejected from the inlet portion toward the downstream in the feeding direction, and at the start end side of the feeding roller, the medium to be ejected is formed. A dive prevention device for preventing dive into the gap is provided.
According to a seventh aspect of the present invention, there is provided a liquid ejecting apparatus including the frontage restricting device in the medium separating apparatus according to the sixth aspect.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side sectional view of an ink jet printer 1 which is a recording apparatus or a liquid ejecting apparatus to which a frontage regulating apparatus in a paper separating apparatus according to the present invention is applied.

  As shown in FIG. 1, the inkjet printer 1 has a schematic configuration in which a feeding unit 5 is provided at the upper rear portion of the apparatus main body 3 and a discharge unit 7 is provided in front of the apparatus main body 3. As shown in FIG. 1, the feeding unit 5 includes a hopper 11 on which a plurality of sheets of recording media can be stacked, and the hopper 11 is provided with a medium support 12.

  As shown in FIG. 1, the sheet positioned at the uppermost portion of the hopper 11 is brought into frictional contact with the outer peripheral surface of the feeding roller 13 provided immediately downstream of the hopper 11, so that the retard roller 14 facing the feeding roller 13. Only one sheet is sent out in cooperation with. The feeding roller 13 and the retard roller 14 constitute a medium separation device, and the configuration will be described in detail later.

  The sheet fed from the hopper 11 reaches a feed roller 19 composed of a lower feed driving roller 15 and an upper feed driven roller 17 provided in the apparatus main body 3, and a precise feeding operation in the recording process by the drive system. The recording head 21 is fed to the recording head 21 located downstream of the feeding roller 19.

  The recording head 21 is supported by a carriage 23, and the carriage 23 can reciprocate in the main scanning direction. A platen 25 is provided at a position facing the recording head 21, and the platen 25 is responsible for supporting the paper from below when recording on the paper by the recording head 21.

  The distance between the recording head 21 and the platen 25, that is, the medium gap, can be appropriately adjusted according to the thickness of the sheet by moving the carriage 23 supporting the recording head 21 up and down. In a state where the medium gap is properly adjusted, the sheet passes through the platen 25 smoothly, and high-quality recording is performed. The sheet recorded by the recording head 21 is discharged from the discharge unit 7. Are sequentially discharged by a discharge roller 27 provided in The discharge roller 27 includes a lower discharge drive roller 29 and an upper discharge jagged roller 31. The discharge roller 27 has a mechanism that is pulled out and discharged by the rotation drive of the discharge drive roller 29.

Hereinafter, the medium separation device of the present invention will be described in detail. FIG. 2 is a perspective view showing the periphery of the frontage regulating device in the medium separating device.
As shown in FIG. 2, the feeding roller 13 is a D-shaped roller as viewed from the side, and forms a portion where the sheet can be sandwiched by cooperation with the outer peripheral surface of the retard roller 14, that is, a nip point 33 (see FIG. 5). And a flat portion 37 that is notched flat and does not form a nip point between the outer peripheral surface of the retard roller 14.

  The retard roller 14 is a cylindrical roller having a horizontal rotation shaft, and is supported rotatably with respect to the retard roller support frame 39. The retard roller support frame 39 is surrounded by a coil spring (not shown) around the support shaft. The retard roller 14 tends to be constantly urged toward the feed roller 13, that is, upward.

  The retard roller 14 is rotated by following the feed roller 13 when feeding only one sheet, but is not driven by the feed roller 13 when feeding two or more sheets. The lower sheet of the uppermost sheet is separated so as not to be fed to the recording apparatus side.

  As shown in FIG. 2, on both sides of the retard roller 14, a rising portion 45 formed from a frame that supports the feeding roller 13 is formed, and the sheet passes directly above the rising portion 45 from the hopper 11 side. It passes through a medium guide path 47 (shown by an arrow in FIG. 2) formed so as to pass, and is supplied to the feeding roller 13 side. In the middle of the medium guide path 47, immediately before the nip point 33 between the feeding roller 13 and the retard roller 14, an opening 51 is formed for the sheet P to enter between the two rollers.

  Two frontage restricting members 53 extending from both sides to the frontage 51 are formed from the upper end of the rising portion 45, and each frontage restriction member 53 is a sheet P guided to the frontage 51. A contact restricting portion 55 for restricting the number of sheets, and a medium guide surface 57 extending from the upper end of the contact restricting portion 55 to the nip point 33 side.

  The contact restriction portion 55 is formed so as to be substantially orthogonal to the direction in which the sheet P is conveyed along the medium guide path 47, and between the upper end of the contact restriction portion 55 and the outer peripheral surface 35 of the feeding roller 13. A gap is formed so that several sheets can pass. With such a configuration, when a plurality of sheets P are conveyed, the sheet positioned below the several sheets that can pass through the gap has its leading end abutted against the abutment restricting portion 55, so that As a result of hindering the above progress, the number of sheets P fed between the feeding roller 13 and the retard roller 14 can be limited.

  FIG. 3 shows the shape of the medium guide surface 57, that is, approximately one from the entrance of the front end 51 along the guide direction of the paper P to the outer peripheral surface 35 of the feed roller 13 toward the downstream in the feed direction. FIG. 6 is an enlarged side sectional view showing a flat medium guide surface 57 as a surface shape capable of forming such a gap. As described in the background art section, the conventional medium guide surface is formed so as to form a convex curved surface on the upper side. However, in the present invention, flattening the medium guide surface 57 is one of the constituent requirements. In the present invention, as will be described later with reference to FIG. 5, an expansion portion 59 that is a recording medium jump-in preventing device is formed on the start end side of the outer peripheral surface 35 of the feeding roller 13.

  In FIG. 3, in order to compare the case where the expansion part 59 is formed (FIG. 5) and the case where the expansion part is not formed, the expansion part 59 is dared to be omitted. The conventional medium guide surface 57 is formed so as to form a convex curved surface on the upper side, and the distance between the outer peripheral surface 35 of the feeding roller 13 and the medium guide surface 57 becomes narrower toward the front. As a result, the leading end of the paper P that has been multi-fed can be shifted prior to paper separation due to the action of the feed roller 13 and the retard roller 14, so that the preliminary separation function of paper separation by the retard roller 14 is provided. It was something that could be fulfilled.

  However, when feeding a sheet having a relatively large coefficient of friction between sheets, such as a semi-gloss postcard, if the medium guide surface 57 is formed to have a convex curved surface on the upper side as in the prior art, double feeding is performed. The pressed sheets are pressed to increase the adhesion between the sheets, so that the desired sheet separating function is not exhibited and the sheets are directly fed to the recording process as they are. In order to solve this problem, as shown in FIG. 3, the medium guide surface 57 is flattened so that the sheets are not compressed.

  In the present invention, in addition to flattening the medium guide surface 57, as shown in FIG. 5, the start end side of the outer peripheral surface 35 of the feeding roller 13, that is, the side of the outer peripheral surface 35 that first contacts the retard roller 14 is provided. The expansion portion 59, which is a recording medium jump-in preventing device, is formed on the recording medium. The reason will be described below. Here, in the present specification, when referring to the starting end side of the feed roller, not only the outer peripheral surface 35 but also the feed roller portions (for example, flange portions) on both sides of the portion where the outer peripheral surface 35 first contacts the retard roller 14. Is included.

  FIG. 4 is an explanatory diagram showing the adverse effects when the medium guiding surface 57 is flattened and no inflating portion is provided. Around the feed roller 13, a return lever (not shown) is provided for returning the paper that has been double fed and separated by the action of the retard roller 14 to the hopper side. There is a sheet that is not completely returned to the hopper due to the return operation of the sheet by the return lever, and such a sheet remains near the top dead center position of the rotation range of the return lever. This remaining sheet is in a position closer to the front opening 51 than the other sheet bundle completely returned to the hopper. Therefore, for the next feeding, when the paper return lever falls to the downstream side in the paper feeding direction and the hopper starts to rise, the paper that has been completely returned to the hopper is brought to the outer peripheral surface 35 of the feeding roller. Before the contact, the uppermost sheet (the sheet that has not been completely returned into the hopper) may jump into the gap between the retard roller 14 and the feeding roller 13 due to vibration or warping of the sheet. is there. By making the medium guide surface 57 flat, the tendency of such jumping becomes larger. When a relatively stiff sheet such as a postcard jumps into the gap between the front edges, the following problems occur.

  The example shown in FIG. 4A shows a state in which the uppermost rigid paper P jumps into the gap of the frontage for a relatively long distance. In the upper left diagram of FIG. 4A, the hopper 11 is in the middle of rising, and the uppermost sheet is not sandwiched between the feeding roller 13 and the hopper 11. Thereafter, when the state shown in the lower right diagram of FIG. 4A is reached, the hopper 11 is completely raised, and the uppermost sheet is sandwiched between the feeding roller 13 and the hopper 11 to move forward. Receives sending force. Then, the front end of the paper P abuts against the surface of the retard roller 14 in a state of projecting from the original set position. In this state, when the paper P is fed by the paper feeding force of the hopper 11 and the feeding roller 13, the leading edge of the paper P pushes down the retard roller 14, and the retard roller 14 stops at its lower limit position. For this reason, the feed roller 13 cannot contact the retard roller 14, so that the retard roller 14 cannot rotate following the feed roller 13 and paper feed cannot be realized.

  The example shown in FIG. 4B shows a state in which the uppermost rigid paper P has jumped into the gap of the frontage for a relatively short distance. In this example, as shown in the upper left diagram of FIG. 4B, the feed roller 13 pushes down the retard roller 14 to the vicinity of the time when the rotation angle of the feed roller 13 is 80 degrees, but at this time, the leading edge of the sheet protrudes. In this state, it hits the surface of the retard roller 14. In this state, when the paper P is fed by the paper feeding force of the hopper 11 and the feeding roller 13, as in the example of FIG. 4A, the leading edge of the paper P is shown in the lower right diagram of FIG. However, the retard roller 14 is pushed down, and the feed roller 13 is separated from the retard roller 14, so that the sheet feeding cannot be realized.

  Therefore, in order to prevent such a phenomenon from occurring, in the present invention, as shown in FIG. 5, the expanding portion 59 is formed on the start end side of the outer peripheral surface 35 of the feeding roller 13. FIGS. 6A and 6B show the feeding operation up to a rotation angle of 0 to 80 degrees of the feeding roller 13 when the medium guide surface 57 is flattened and the expanding portion 59 is formed. Indicates.

  When the feeding roller 13 rotates 60 degrees from the home position shown in FIG. 6A as shown in FIG. 6B, the corner portion 61 of the feeding roller 13 starts to push down the retard roller 14. At this time, the expanding portion 59 closes the gap between the feeding roller 13 and the retard roller 14, so that the paper can be prevented from jumping in as described with reference to FIGS.

  As shown in FIG. 6C, after the feed roller 13 rotates by 70 degrees and the retard roller 14 starts to be pushed down by the feed roller 13, the feed roller 13 feeds as shown in FIG. When the roller 13 rotates 74.13 degrees, the leading edge of the uppermost sheet comes into contact with the feeding roller 13 and feeding starts. At this time, since the expanding portion 59 exceeds the apex portion that is the boundary between the contact restriction portion 55 of the front opening regulating member 53 and the medium guide surface 57, the sheet is placed in the gap between the feeding roller 13 and the retard roller 14. Can enter. Then, as shown in FIG. 6-2 (e), thereafter, the double fed paper is separated as in the conventional case, and the paper is fed to the recording process.

  The embodiment in which the expanding portion 59 is formed on the start end side of the outer peripheral surface 35 of the feeding roller 13 has been described above. However, the expanding portion 59 is a feeding roller in the flange portion 63 of the feeding roller 13 as shown in FIG. An expansion portion 59 that is a recording medium jump-in preventing device may be formed in a portion corresponding to the start end position of the 13 outer peripheral surfaces 35.

  INDUSTRIAL APPLICABILITY The present invention can be used for a recording apparatus and a liquid ejecting apparatus that include a feeding device that can reliably feed a recording material such as a plurality of cut sheets one by one from a hopper stocked.

1 is a side sectional view of an inkjet printer 1 to which the present invention is applied. It is a perspective view which shows the frontage restricting device periphery in a medium separator. It is an expanded sectional side view which shows the medium guide surface made flat. (A) (b) is explanatory drawing which shows the bad effect when a medium guide surface is made flat and an expansion part is not provided. It is an expanded sectional side view of embodiment which formed the expansion part in the starting end side of the outer peripheral surface of a feed roller. (A) (b) (c) is a figure explaining the feeding operation | movement of a feeding roller at the time of forming an expansion part, and is partially expanded and shown. (D) (e) is a figure explaining the feeding operation | movement of a feeding roller at the time of forming an expansion part, and is partially expanded and shown. It is an expanded sectional side view of embodiment which formed the expansion part in the flange of the feed roller. (A) (b) (c) is explanatory drawing which shows the paper separation process of the conventional medium separator. (D) (e) is explanatory drawing which shows the paper separation process of the conventional medium separator, and is partially expanded and shown. (G) and (h) are explanatory views showing a sheet separating process of a conventional medium separating apparatus, and are partially enlarged.

Explanation of symbols

1 Inkjet printer, 3 device body, 5 feeding section, 7 discharging section,
11 hopper, 12 media support, 13 feeding roller, 14 retard roller,
DESCRIPTION OF SYMBOLS 15 Feed drive roller, 17 Feed driven roller, 19 Feed roller, 21 Recording head 23 Carriage, 25 Platen, 27 Ejection roller, 29 Ejection drive roller,
31 Ejection roller, 33 Nip point, 35 Outer peripheral surface, 37 Flat part,
39 retard roller support frame, 45 start-up part, 47 medium guide path,
51 frontage part, 53 frontage restriction member, 55 contact restriction part, 57 medium guide surface,
59 Expansion part, 61 Corner part of feeding roller, 63 Flange part, P paper

Claims (6)

A medium separating apparatus comprising a feeding roller and a retard roller provided opposite to the feeding roller,
In the medium guide path to the feeding roller, a front opening restricting member that extends from both the left and right sides of the front opening is provided at a front opening just before the nip point that is a medium separation position by the feeding roller.
The frontage restricting member includes a contact restricting portion with which a leading end of a recording medium guided to the frontage portion abuts, and a medium guide surface extending from the upper end of the contact restricting portion to the nip point side,
The medium guide surface is substantially uniform from the inlet portion along the guide direction of the recording medium to the downstream side in the feeding direction of the recording medium, in a side view, with the outer peripheral surface of the feeding roller. It is a surface shape with a gap,
At the timing before the recording medium is fed and at the timing when the gap is formed between the medium guide surface and the outer peripheral surface of the feeding roller, the sheet feeding path related to the gap is closed. A medium separation device comprising a jump-in preventing unit that protrudes and prevents a recording medium from jumping into the gap. The medium separating apparatus according to claim 1, wherein the feeding roller is a D-shaped roller in a side view,
The dive preventing portion of the recording medium, the medium separation device, characterized in that the expanding portion formed on the starting end side of the outer peripheral surface of the feed roller. The medium separating apparatus according to claim 1, wherein the feeding roller is a D-shaped roller in a side view,
The dive preventing portion of the recording medium, the medium separation device, characterized in that the expanding portion formed on the starting end side of the flange portion of the side view D shape provided on both sides of the outer peripheral surface of the feed roller. The medium separating apparatus according to any one of claims 1 to 3, wherein the expanding portion is located in a rotational direction before a nip point that is a medium separating position by the feeding roller. Media separator .   5. The medium separation device according to claim 1, wherein the recording medium jump-in prevention portion is a vertex portion that is a boundary between the contact restriction portion of the frontage restriction member and the medium guide surface. In addition, a medium separating apparatus characterized in that a recording medium is blocked by closing a paper feed path related to the gap to prevent the recording medium from jumping into the gap. A recording apparatus comprising the medium separating apparatus according to claim 1.

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