JP3695013B2 - Paper feeding device and printing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet feeding device and a printing apparatus, and more particularly, to a sheet feeding device that guides a sheet with a thin plate-shaped guide piece between a feeding roller and a pressing roller in contact therewith.
[0002]
[Background Art and Problems to be Solved by the Invention]
Conventionally, as shown in FIG. 7, one side of the feed roller 94 is exposed from the opening 93 of the passage walls 91 and 92 that form the paper passage for feeding the paper, and a pressing roller 96 is provided on the exposed portion of the feed roller 94. It is known that a sheet is sandwiched between the feed roller 94 and the pressing roller 96 and is fed downstream by rotating the feed roller 94 with a drive source, and printing operation is performed on the downstream path wall 92. ing.
[0003]
In this type of structure, the sheet S is guided between the rollers 94 and 96 through the lower surface of the lever member 97 that supports the pressing roller and the upstream passage wall 91, but the pressing roller 96 has a relatively small diameter. If this is the case, a dent close to a right angle can be formed at the intersection 95 between the lower surface of the lever member 97 and the outer periphery of the pressing roller 96. There is. In particular, in a printing apparatus in which a printing mechanism is arranged in the immediate vicinity of the pressing roller 96 in order to print to the vicinity of the rear end of the paper, the pressing roller 96 should be made as small as possible to avoid interference with the printing mechanism. I must. The interval between the lever member 97 and the feed roller 94 must be secured at a predetermined value or more in consideration of assembling errors and the like. The smaller the pressing roller 96 is, the closer the intersection 95 becomes to a right angle.
[0004]
Further, as shown in FIG. 7, the paper feed device that feeds the paper at an acute angle with respect to the downstream passage wall 92 from which the contact point between the feed roller 94 and the pressing roller 96 is slightly shifted to the downstream side. In this case, the sheet is not parallel to the downstream passage wall 92 but is sent at an acute angle from above and moves while being in close contact with the passage wall 92. There is an advantage that the work is less likely to lift. However, since the pressing roller 96 is biased to the downstream side with respect to the feeding roller 94, when viewed from the upstream side, the intersection of the leading edge of the sheet beyond the top of the feeding roller 94 and the outer periphery of the pressing roller and the lower surface of the lever member is formed. It becomes easy to hit 95. In the specification and drawings of US Pat. No. 5,527,123, a thin plate-like guide piece such as a leaf spring is provided on the member side supporting the pressing roller, and the guide piece approaches the outer periphery of the feed roller from the upstream side. In this example, the pressing roller is in contact with the outer periphery on the downstream side of the feeding roller. In this case, in order to print as close as possible to the trailing edge of the paper, even if the paper leaves the pressing roller, it is sandwiched between the guide piece and the feeding roller. In what can be done, there is no difference from the above, and the above problems have not been completely solved.
[0005]
The present invention makes it possible to smoothly guide a sheet between a feed roller and a pressing roller in contact with the feed roller, and to accurately perform the cueing of the sheet with respect to the printing mechanism.
[0006]
[Means for Solving the Problems and Effects of the Invention]
In order to achieve this object, the invention according to claim 1 includes a passage wall forming a paper passage for feeding paper,
A feed roller exposed on one side from the passage wall;
A pressing roller that abuts the exposed portion of the feed roller and feeds the paper in cooperation with the feed roller; and
Located on the opposite side of the passage wall across the paper passage, extends from the upstream side in the paper feed direction of the two rollers toward the feed roller, and elastically acts on the outer periphery of the feed roller upstream of the contact point of the two rollers. The sheet feeding device includes a thin plate-shaped guide piece that is in contact with the sheet feeding device.
[0007]
With this configuration, when the paper is fed toward the rollers from the upstream side, the leading edge of the paper is guided to the passage wall or the guide piece, enters the contact point between the guide piece and the feed roller, and is fed to the press roller while being pushed by the guide piece. It is sandwiched between the rollers and can be fed by both rollers. Therefore, even if the pressing roller has a very small diameter, before the leading edge of the sheet reaches the pressing roller, the sheet is pressed toward the feeding roller by the guide piece, and does not contact the upper part of the outer periphery of the pressing roller. It is sandwiched between the feed rollers and can smoothly feed to the downstream side.
[0008]
According to a second aspect of the present invention, in the first aspect, the pressing roller is located on the upstream side in the paper feeding direction of the two rollers on the opposite side of the passage wall across the paper passage and parallel to the feeding roller. The guide piece is supported by a lever member that can swing around an axis, and one end of the guide piece is fixed to the lever member and the other end is in contact with the feed roller.
[0009]
With this configuration, the effect of the first aspect of the invention can be obtained, and the pressing roller is supported by the swingable lever member and contacts the feed roller with a predetermined pressure, and the guide piece is also fixed to the lever member. If the other end is brought into contact with the feed roller and both are assembled to the lever member, the relative positions of the two are naturally determined and can be assembled easily.
[0010]
According to a third aspect of the present invention, a feed roller and a pressing roller biased toward the feed roller are provided, the sheet is sandwiched between the two rollers, and the upper side of the passage wall provided on the downstream side. In a paper feeding device that feeds at an acute angle from
A lever member in which the pressing roller is positioned on the upstream side of the both rollers in the sheet feeding direction, on the opposite side of the feeding roller across the sheet path between the two rollers, and is swingable around an axis parallel to the feeding roller Supported by
The sheet feeding device is provided with a thin plate-like guide piece that elastically contacts the outer circumference of the feeding roller from the upstream side of the feeding direction of the both rollers to the upstream side of the contact point of the both rollers.
[0011]
In this configuration, the sheet is fed from the upper side so as to form an acute angle rather than being parallel to the downstream path wall from the pressing roller and the feed roller, and moves while being in close contact with the downstream path wall. In the case of performing a printing operation or the like on the side passage wall, the fed paper is less likely to float. However, the leading edge of the paper beyond the top of the feeding roller is likely to hit the intersection formed by the outer periphery of the pressing roller and the lower surface of the lever member. And is sandwiched between the pressure roller and the feed roller, and can be smoothly fed to the downstream side.
[0012]
According to a fourth aspect of the present invention, in any one of the first to third aspects, the sheet feeding device performs registration of the leading edge of the sheet on the upstream side of the contact point between the feeding roller and the guide piece. With this configuration, the effect of any one of claims 1 to 3 is obtained, and the front end of the sheet is registered upstream of the contact point between the feed roller and the guide piece, and then the feed roller and the pressing roller are used. Hold it and send it out. As in the prior art, the leading edge of the sheet does not hit the position other than the normal registration position with respect to the outer periphery of the pressing roller, and registration can be performed accurately.
[0013]
The invention according to claim 5 is a feed roller;
A pressing roller that sandwiches the paper between the feed roller and feeds it downstream;
A thin plate-like guide piece that elastically contacts the outer periphery of the feed roller on the upstream side of the contact point between the rollers from the upstream side in the paper feed direction of the both rollers, and performs registration of the front end of the paper on the upstream side thereof;
A printing mechanism provided on the downstream side of the two rollers;
And a control unit that controls a cueing amount of the sheet from the registration position toward the printing mechanism based on a signal indicating the type of the sheet.
[0014]
With this configuration, the leading edge of the sheet is registered on the upstream side of the contact point between the feed roller and the guide piece, and thereafter, the sheet is sandwiched and fed by the feed roller and the pressing roller. As in the prior art, the leading edge of the sheet does not hit the position other than the normal registration position with respect to the outer periphery of the pressing roller, and registration can be performed accurately. In this case, since the outer periphery of the feed roller and the guide piece approach very slowly, the amount of biting between the outer circumference of the feed roller and the guide piece changes between normal thin paper and thick paper such as an envelope, that is, the registration position. Changes. The control device controls printing from the registration position toward the printing mechanism based on a signal indicating the type of paper, thereby enabling printing from a substantially constant cueing position.
[0015]
A sixth aspect of the present invention is the printing apparatus according to the fifth aspect, wherein the printing mechanism includes an ink jet print head that prints by ejecting ink droplets toward a sheet. The printing apparatus according to claim 5 can be suitably implemented in an apparatus including an ink jet print head.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described with reference to the drawings embodying an ink jet printing apparatus.
[0017]
In this printing apparatus, the paper S is fed out from the paper feeding device 2 one by one, and further, the paper feeding device 7 feeds the paper to the front surface of the printing mechanism 1, performs predetermined printing on the paper S, and discharges it out of the printing device. The sheet S is a so-called cut sheet cut into a rectangular shape having a certain size.
[0018]
The printing mechanism 1 includes a carriage 11 that reciprocates along a guide rail 10, an ink cartridge 12 that is supported by the carriage 11, and a print head 13. The guide rail 10 is arranged in the width direction of the paper S supplied from the paper feeding device 2, that is, in the direction parallel to the surface of the paper S and perpendicular to the feeding direction of the paper S. During printing, ink droplets are ejected from the print head 13 toward the paper S passing under the carriage 11 while the carriage 11 is reciprocally driven by a drive source (not shown) (motor 103 in FIG. 5). An image made up of images and figures is printed.
[0019]
In the paper feeding device 2, a hopper 3 that accommodates the sheets S in a stacked state, a feeding mechanism 4 for feeding the sheets S from the hopper 3, and a wall portion 5 provided so that the sheets S fed from the hopper 3 abut against each other. And are provided. Inside the hopper 3, a push-up plate 31 that supports the stacking of the sheets S is provided. The push-up plate 31 is rotatable about a rotation shaft 34 provided on the rear end side of the hopper 3, and the front end side of the paper S is pushed up and biased toward the feeding mechanism 4 by a spring 35.
[0020]
The delivery mechanism 4 is provided with a support shaft 40 parallel to the width direction of the paper S and a paper feed roller 41 attached on the support shaft 40. The wall 5 has a sheet receiving surface 50 for receiving the sheet S descending from the tip of the hopper 3, and an inclined surface 51 that is continuous above the sheet receiving surface 50 and rises from the hopper 3 toward the front in the feeding direction. Is formed. The inclined surface 51 has an action of separating the sheets S sent out from the hopper 3 one by one, and a known separating means such as a friction member may be provided as appropriate.
[0021]
The paper feeding device 2 is further provided with an insertion port 21 for manual paper on the upper surface of a cover member 63 that constitutes the outline of the printing device. The manual insertion port 21 is opened downstream of the feeding mechanism 4 and upstream of the paper feeding device 7.
[0022]
The sheet feeding device 7 includes a feeding roller 70 and a pressing roller 71 provided on the upstream side of the printing mechanism 1, a lever member 75 that supports the pressing roller 71, and discharge roller pairs 72 and 73 provided on the downstream side. The passage walls 61 and 62 for forming the paper passage, the paper detector 8 and the like are provided. The passage walls 61 and 62 are formed in a part of the frame 60 of the printing apparatus that supports the hopper 3, the delivery mechanism 4, and the printing mechanism 1, and extend continuously from the sheet receiving surface 50 to a position facing the print head 13.
[0023]
The feed roller 70 is rotatably provided around an axis parallel to the paper width direction, and most of the feed roller 70 is located below the passage walls 61 and 62, and a part of the upper surface is formed from the opening 64 between the passage walls 61 and 62. Is exposed. A plurality of pressing rollers 71 are provided in the sheet width direction as shown in FIG. The plurality of pressing rollers 71 are formed on a single rod-like member 74 at an appropriate number (for example, three) at intervals, and a small diameter portion 74a is formed between the pressing rollers.
[0024]
A pair of lever members 75 that support the pressing roller 71 are provided for each rod-shaped member 74, and one member 75a of the pair rotatably supports a shaft portion 74b at one end of the rod-shaped member 74, and the other. The thing 75b supports the axial part 74c of the other end of the rod-shaped member 74 rotatably. Each part 75a, 75b is supported by the attachment member 76 so as to be able to swing independently as follows.
[0025]
As shown in FIGS. 2 and 3, the attachment member 76 is formed long in the paper width direction, and has a plurality of pairs of support pieces 76a at predetermined intervals in the longitudinal direction with respect to the portions 75a and 75b. Each portion 75a, 75b can swing by projecting a shaft 77a on an arm 77 provided in the vicinity of both the left and right sides and fitting the shaft 77a into the bearing hole of the support piece 76a using the elasticity of the arm 77. Supported. The center of the swing is an axis line on the upstream side of both rollers 70 and 71 in the paper feeding direction, on the opposite side of the paper roller with respect to the paper path, and parallel to the feeding roller 70. In this case, the arm 77 and the shaft 77a can be formed on the mounting member 76 side, and the bearing holes can be formed on the portions 75a and 75b.
[0026]
Each part 75a, 75b also urges both ends of the rod-like member 74 toward the feed roller 70 independently by a spring 78 inserted between the attachment member 76 and each part 75a, 75b. In other words, even if there are irregularities on the outer periphery of the feed roller 70 or a change in the thickness of the paper, the rod-like member 74 is tilted so that each pressing roller 71 contacts the feed roller 70 as evenly as possible.
[0027]
As shown in FIG. 1, the lever member 75 has a “<” shape on the side surface, brings the end on the pressing roller 71 side as close as possible to the printing mechanism 1, and the end on the side pressed by the spring 78. It is shaped to rise in a direction away from the passage wall 61 on the upstream side. With this shape, the surface 75 c facing the passage wall 61 forms a paper passage for guiding the leading edge of the paper fed from the paper feeding device 2 to the rollers 70 and 71 together with the passage wall 61.
[0028]
Further, an elastic thin plate-shaped guide piece 79 is fixed to each of the portions 75 a and 75 b of the lever member 75. The guide piece 79 is made of a resin film material or a leaf spring or the like, and one end is affixed to a surface (a position slightly above the surface 75c) away from the pressing roller 71 of each of the portions 75a and 75b. As shown in FIG. 4, the free end protrudes downstream from the printing mechanism side end of each of the portions 75a and 75b through the small diameter portion 74a between the pressing rollers 71. The guide piece 79 is in elastic contact with the upper surface of the feed roller 70 on the upstream side of the pressing roller 71, and the leading end of the sheet is registered between the guide piece 79 and the feed roller 70 on the upstream side of the contact point P. A nip portion is formed. The guide piece 79 is affixed to a portion of the lever member 75 that is submerged than the surface of the lever member 75 and protrudes toward the feed roller 70 while curving at a gentle angle from the surface.
[0029]
The passage wall 62 on the downstream side of the rollers 70 and 71 forms a so-called platen surface facing the print head 13, but is farthest from the print head 13 at the end close to the roller 70 and gradually approaches toward the downstream side. As shown in FIG. The contact portions of the discharge roller pairs 72 and 73 are located at substantially the same height as the upper end of the inclined surface 62a. The upper roller 73 of the discharge roller pairs 72 and 73 is a so-called spur roller having a large number of protrusions on the outer periphery.
[0030]
The pressing roller 71 contacts the feed roller 70 at a position slightly shifted downstream from the contact point of the feed roller 94 with respect to a tangent line passing through the outer periphery of the feed roller 94 and the contact portion of the discharge roller pair 72 and 73. As a result, a tangent line A passing through the contact points of both rollers 70 and 71 forms an acute angle B with respect to the inclined surface 62a from above. The guide piece 79 is also inclined downward to form an acute angle with respect to the inclined surface 62a, and is also inclined with respect to a line C connecting the contact portions of the rollers 70 and 71 and the contact portions of the discharge roller pairs 72 and 73. Yes. The lower end of the guide piece 79 protrudes toward the inclined surface 62a from the line C.
[0031]
Therefore, the leading edge of the sheet fed from the rollers 70 and 71 advances at an acute angle against the inclined surface 62a while being in close contact with the inclined surface 62a, and is sandwiched between the discharge roller pairs 72 and 73. The sheet between the rollers 70 and 71 and the discharge roller pair 72 and 73 is set so that the discharge roller pair 72 and 73 feed the sheet at a slightly higher speed than the rollers 70 and 71. It becomes a state stretched along. When the trailing edge of the sheet comes off the rollers 70 and 72, the trailing edge advances to a position very close to the print head 13 while being pressed by the guide piece 79. In this way, the leading edge and the trailing edge of the sheet are avoided from floating and rubbing the print head 13 and being stained with ink.
[0032]
FIG. 5 is a block diagram showing a schematic electrical configuration of the printing apparatus. The control device 101 includes a known CPU, ROM, RAM, and the like, and drives the print head 13, the paper feed motor 102, and the carriage motor 103 based on data received through the I / F unit. As shown in FIG. 1, the paper detector 8 includes a lever 81 protruding into a paper passage on the upstream side of the rollers 70 and 71 and switch means 82 operated by the lever, and controls whether or not paper is present in the passage. 101 is informed.
[0033]
FIG. 7 is a flowchart showing the control contents of the control device 101 for sucking paper from the paper feeding device 2 to the print start position. When a paper suction signal is input from a host device such as a personal computer, the control device drives the paper feed motor 102 to start the paper suction (S1). First, when the paper feed roller 41 is rotated clockwise in FIG. 1 by the paper feed motor 102, one sheet of paper S is sent out from the hopper 3. The leading edge of the sheet S enters the sheet path between the surface 75c of the lever member 75 or the guide piece 79 and the path wall 61 while being guided by them, and after operating the sheet detector 8, the leading edge of the sheet S and the guide are provided. Registration is performed at the nip portion between the pieces 79 (FIG. 4). At this time, the motor 102 stops the rollers 70 and 72 or rotates counterclockwise, and does not send the paper S downstream from the registration position.
[0034]
When the motor 102 rotates by a distance from the hopper 3 to the registration position, the rotation direction is switched and the paper feed roller 41 is stopped, while the rollers 70 and 72 are rotated clockwise to feed the paper while being pushed by the guide piece 79. The roller 70 is sent toward the pressing roller 71, is sandwiched between the rollers 70, 71, and is sent toward the print head 13. If the paper detector 8 detects the paper before this (S2: Yes), the control device 101 discriminates data relating to the paper type received from the host device (S5), and in the case of normal thin paper (S5: Yes), the motor 102 is rotated by a certain amount from the registration position, and the first print position of the paper is opposed to the print head 13 (S7). In the case of thick paper such as postcards and envelopes (S5: No), the amount of the tip entering the nip portion between the feed roller 70 and the guide piece 79 is reduced, so by rotating the motor 102 by the above-mentioned fixed amount + α, The first print position with the same upper margin as the thin paper can be made to face the print head 13 (S6).
[0035]
That is, the control device 101 corresponds to the type of the sheet, and the cueing amount of the sheet from the registration position toward the printing mechanism 1 (the above-mentioned fixed amount for thin paper and the above-mentioned fixed amount + α for thick paper). Is read in advance in accordance with a signal indicating the paper type, and the cueing position related to the paper type is controlled to be substantially constant. Α is determined by the size of the feed roller 70, the elastic force of the guide piece 79, and the like. The paper types can be determined not only in two types but also in multiple stages.
[0036]
If the paper detector 8 does not detect the paper even if the motor 102 is rotated more than the distance corresponding to the registration position from the beginning of the rotation of the paper feed roller 41 (S2: No, S3: Yes), whether the paper has jammed or the hopper Error processing is performed assuming that there is no sheet in 3 (S14), and the control is terminated.
[0037]
When a sheet is inserted from the manual insertion slot 21 and the leading end of the sheet is at the registration position, the sheet is detected from the beginning of inserting the sheet (S2: Yes), and the motor 102 rotates the sheet feeding roller 41. Without doing so, the rollers 70 and 72 are rotated clockwise by an amount corresponding to the type of paper as described above (S6, S7).
[0038]
When the sheet is normally sucked, the control device 101 has a sheet feed until a predetermined distance is fed after the line feed accompanying the printing operation proceeds and the trailing edge of the sheet passes the sheet detector 8. As a result, the printing operation is continued and printing is performed up to the rear end of the paper. The margin at the rear end of the sheet can be set as appropriate. However, by pressing the sheet with the guide piece 79, even if it is separated from the pressing roller 71, the lifting of the rear end of the sheet can be suppressed and printing can be accurately performed up to the vicinity of the rear end.
[0039]
As described above, when the paper S is fed toward the both rollers 70 and 71 from the paper feeding device 2 side, the leading edge of the paper S is guided to the passage wall 61 or the guide piece 79, and the nip between the guide piece 79 and the feed roller 70. And is fed to the pressing roller 71 while being pushed by the guide piece 79 by the rotation of the feeding roller 70, is sandwiched between the feeding roller 70 and the pressing roller 71, and is fed by both rollers 70, 71. Therefore, even if the pressing roller 71 has a very small diameter, before the leading edge of the sheet reaches the pressing roller 71, the sheet is pressed toward the feeding roller 70 by the guide piece 79 and contacts the upper part of the outer periphery of the pressing roller 71. And is smoothly sandwiched between the pressing roller 71 and the feed roller 70.
[0040]
In addition, as a result, the leading edge of the sheet does not hit a position other than the normal registration position with respect to the outer periphery of the pressing roller as in the prior art, and registration can be performed accurately, and printing can be performed from a substantially constant cueing position. .
[0041]
In this case, since the outer periphery of the feed roller and the guide piece approach very slowly, the registration position changes between normal thin paper and thick paper such as an envelope, but the registration position is based on a signal indicating the type of paper. By controlling the paper feed amount from the paper to the printing mechanism, it is possible to print from a substantially constant cue position regardless of the paper type.
[0042]
Further, the pressing roller 71 and the guide piece 79 are assembled to the lever member 75 and both of them are brought into contact with the feeding roller 70, so that they can be easily assembled, the surface of the feeding roller 70 has irregularities, the paper Even if the lever member 75 moves up and down slightly as the feed roller rotates, the guide piece 79 maintains contact with the feed roller 70 due to elastic deformation, and the sheet is guided accurately. And can be resisted. Further, since the pressing roller 71 and the guide piece 79 are arranged at appropriate intervals in the width direction of the sheet, the above-described pressing effect by the feeding roller 71 and the guiding piece 79 can be achieved over the entire sheet width. Paper can be fed accurately without tilting.
[0043]
In the case where the paper is fed from the pressing roller 71 and the feeding roller 70 so as not to be parallel to the downstream passage wall 62 but at an acute angle from above, the leading edge of the paper beyond the top of the feeding roller 70 is the pressing roller. It is easy to hit the intersection formed by the outer periphery of 71 and the lower surface of the lever member 75. Before the leading edge of the sheet approaches the intersection, the leading edge is pushed toward the feeding roller 70 by the guide piece 79, and the gap between the pressing roller 71 and the feeding roller 70 is increased. And can be sent out so as to be in close contact with the passage wall 62.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an essential part of a printing apparatus embodying the present invention.
FIG. 2 is a partial front view of a pressing roller 71, a lever member 75, and a mounting portion 76.
3 is a perspective view showing a configuration for supporting a lever member 75 on a mounting member 76. FIG.
4 is a partially enlarged view of the sheet feeding device 7 of FIG. 1;
FIG. 5 is a block diagram showing a schematic electrical configuration of the printing apparatus.
FIG. 6 is a flowchart showing control details for paper inhalation.
FIG. 7 is a view corresponding to FIG. 4 of a paper feeding device of a conventional printing apparatus.
1 Printing Mechanism 61, 62 Passage Wall 70 Feeding Roller 71 Pressing Roller 72, 73 Discharge Roller Pair 75 Lever Member 79 Guide Piece

Claims (6)

A passage wall forming a paper passage for feeding paper;
A feed roller exposed on one side from the passage wall;
A pressing roller that abuts the exposed portion of the feed roller and clamps and feeds the paper in cooperation with the feed roller;
Located on the opposite side of the passage wall across the paper passage, extends from the upstream side in the paper feed direction of the two rollers toward the feed roller, and elastically acts on the outer periphery of the feed roller upstream of the contact point of the two rollers. A sheet feeding device comprising a thin plate-shaped guide piece that contacts the sheet feeding device. 2. The lever according to claim 1, wherein the pressing roller is positioned on the upstream side in the paper feeding direction of the two rollers on the side opposite to the passage wall across the paper passage and is swingable about an axis parallel to the feeding roller. A sheet feeding device supported by a member, the guide piece having one end fixed to the lever member and the other end contacting the feed roller. In a paper feeding device that includes a feeding roller and a pressing roller biased toward the feeding roller, sandwiches the paper between the two rollers, and feeds the passage wall provided on the downstream side at an acute angle from above. ,
A lever member in which the pressing roller is positioned on the upstream side of the both rollers in the sheet feeding direction, on the opposite side of the feeding roller across the sheet path between the two rollers, and is swingable around an axis parallel to the feeding roller Supported by
A sheet feeding device provided with a thin plate-like guide piece that elastically contacts the outer periphery of the feeding roller from the upstream side of the feeding direction of the both rollers to the upstream side of the contact point of the both rollers. 4. The sheet feeding device according to claim 1, wherein the leading edge of the sheet is registered upstream of a contact point between the feeding roller and the guide piece. A feed roller;
A pressing roller that sandwiches the paper between the feed roller and feeds it downstream;
A thin plate-shaped guide piece that elastically contacts the outer periphery of the feed roller on the upstream side of the contact point between the rollers from the upstream side in the paper feed direction of the both rollers, and performs registration of the front end of the paper on the upstream side thereof;
A printing mechanism provided on the downstream side of the two rollers;
And a control device that controls a cueing amount of the paper from the registration position toward the printing mechanism based on a signal indicating a paper type. The printing apparatus according to claim 5, wherein the printing mechanism includes an ink jet print head that prints by ejecting ink droplets toward a sheet.

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