JP3778255B2 - Paper feeder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper feeding device in a recording apparatus such as a printer, and in particular, immediately before the front end of a paper is nipped by a conveyance roller, the working area of a paper side edge aligning member provided in a paper feeding cassette at the rear end of the paper. The present invention relates to a sheet feeding device that is configured so that it does not affect the sheet feeding performance of a conveyance roller due to release of pressure on the sheet side edge.
[0002]
[Prior art]
Conventionally, in a facsimile machine, a copying machine, a printer device, and the like, a paper feeding cassette that stores a plurality of papers in a stacked manner is generally used, and paper is fed one by one from the upper layer side of the paper feeding cassette. And recording.
The sheets fed one by one are intermittently conveyed by the rotation control of a conveyance roller disposed immediately before the recording head. In order to perform high-quality printing, it is necessary to control the rotation of the transport roller with high accuracy, and a DC motor, a stepping motor, or the like is used.
The paper feed cassette is provided with a guide member for aligning the paper side edges and a paper rear edge push member for reliably separating and feeding the uppermost paper by pushing the paper rear edge. On the other hand, a stopper member is provided in the paper feed cassette mounting portion of the apparatus main body, and the paper feed cassette is inserted, and the front wall portion and the side wall portion of the paper feed cassette are abutted against the stopper member so that the recording head Alignment is performed.
[0003]
[Problems to be solved by the invention]
By the way, if the paper transport path from the paper feed cassette to the transport roller is shortened, the apparatus can be miniaturized and the printing speed can be increased. However, if the distance from the paper feed cassette to the transport roller is shorter than the length of the paper, When the transport roller nips the leading edge of the paper, the trailing edge of the paper remains in the paper feed cassette. At this time, if a force is applied to the rear portion of the sheet nipped by the conveying roller in a direction perpendicular to the feeding direction for aligning the sheet side edge, the action becomes a rotational load of the conveying roller. When this load is released during the conveyance of the sheet, the rotation load of the conveyance roller is reduced. Such load fluctuations cause problems such as uneven rotation of the transport roller and reduced print quality.
[0004]
An object of the present invention is a paper feeding device having a paper conveyance path whose distance from a paper feeding cassette to a conveyance roller is shorter than a paper length, and a pressing for aligning the paper side just before the paper leading edge is nipped by the conveyance roller. An object of the present invention is to provide a paper feeding device in which the force is released so that the rear end side of the paper is not in contact with the side wall portion.
Another object of the present invention is to provide a paper feed cassette having a region where the pressing force for aligning the paper side edge is released on the paper delivery side.
[0005]
[Means for Solving the Problems]
According to the first aspect of the present invention, a paper feed cassette for storing paper is provided, a paper feed roller on the paper feed cassette side and a transport roller on the recording head side are arranged, respectively, from the paper feed cassette to the transport roller. A paper feeding device having a paper conveyance path whose distance is shorter than the paper length, which is disposed along the side wall portion, and is a paper side excluding a predetermined distance from the front wall portion on the paper feeding side to the rear wall portion side A paper-side edge aligning member that pushes and aligns the edges, a plurality of springs that apply a force to bias the paper-side edge to the paper-side edge aligning member, and a paper alignment boss that displaces the plurality of springs. A cam mechanism is provided in a paper cassette, and the cam mechanism is configured to cause the plurality of springs to work stepwise by displacing the paper aligning boss when the paper feed cassette is inserted and attached to the paper feeder. , The paper Tansoroe member, when the leading end of the sheet reaches the conveying roller, characterized in that it is configured so as not to act on the sheet side edge.
According to the first aspect of the invention, before the front end of the paper is nipped by the transport roller, the pressure on the paper side end by the paper side end aligning member is released, and the rear end side of the paper is free. Accurate conveyance is performed, and high-quality printing is possible. Further, the printing speed can be increased and the size can be reduced by the short paper conveyance path.
[0006]
According to a second aspect of the present invention, in the first aspect of the invention, a plurality of protrusions for guiding the paper side end are provided on the other side wall portion facing the side wall portion on which the paper side edge aligning member is disposed. It is characterized by being.
According to the second aspect of the present invention, the motor that drives the paper feed roller by reducing the frictional resistance at the time of paper feeding by dispersing the contact portion with the paper side edge by the plurality of protrusions and reducing the contact surface. Reduce the load. In other words, the motor can be miniaturized.
[0007]
According to a third aspect of the present invention, in the first aspect of the invention, the paper-side edge aligning member is composed of a first pressing portion and a second pressing portion that are axially supported at both ends, and both pressing portions are connected to the other pressing portion. An urging means for urging the side wall portion is provided.
According to the third aspect of the present invention, the same effect as in the second aspect can be obtained by pressing a part of the sheet side edge.
[0008]
According to a fourth aspect of the present invention, in the first aspect of the invention, a push plate that presses the front end of the paper against the paper feed roller is disposed at a position where the paper side edge aligning member in the paper feed cassette does not act on the paper side edge. It is characterized by being.
According to the fourth aspect of the present invention, since the paper side edge where the push plate is located is not restrained by the paper side edge aligning member, the paper can be smoothly moved up and down.
[0009]
According to a fifth aspect of the present invention, there is provided a paper feed cassette having a side wall portion opposed to a paper side end of paper to be stored, and aligning the paper side end along the side wall portion by pushing the side end of the paper to the opposite side wall portion side. A paper side edge aligning member is disposed, and a region is provided from the front wall portion on the paper feed side to the rear wall portion side where the pressing of the paper side edge aligning member does not act on the paper side edge. A plurality of springs for applying a force for urging the side edge of the paper to the side edge aligning member; and a paper alignment boss for displacing the plurality of springs. The paper feed cassette is inserted and attached to the paper feeder. The cam mechanism is configured to cause the plurality of springs to work stepwise by displacing the paper alignment boss.
According to the invention described in claim 5, when the paper is sent out from the paper feed cassette, the predetermined length on the rear side of the paper side end in the paper feed cassette is released from the pressing by the paper side edge aligning member. It is possible to reduce the load on the paper feeding system caused by pressing the paper side edge against the side wall.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described. FIG. 1 is a perspective view in which a cover of a printer device to which a paper feeding device according to the present invention is applied is removed, and FIG. 2 is a schematic diagram of the paper feeding device in the printer device.
[0011]
First, an outline of the printer apparatus will be described. The printer apparatus 1 includes a sheet cassette mounting portion 2 provided with a sheet cassette insertion slot 2A on the front side of the apparatus main body, and supplies a plurality of sheets P stacked from the sheet cassette insertion slot 2A. A paper cassette 20 is inserted and mounted. A main frame 110 erected on the bottom frame 40 includes a main shaft 112 that supports a carriage 111 on which the recording head 12 is mounted so as to be movable in the main scanning direction, a carriage 113 that includes a motor 113 and a belt 114 that drive the carriage 111. 115, a paper feeding unit 116, and a carriage home position 118 for performing maintenance such as cleaning of the recording head 12 and ink suction at the rear of the apparatus main body.
[0012]
As shown in FIG. 2, a push plate operating lever 3 having a rotation fulcrum 3a is provided on the bottom frame 40 on the side of the paper feed cassette insertion slot 2A so as to extend to the vicinity of the paper feed roller 6 in the paper feed cassette mounting portion 2. The push plate operating lever 3 is urged toward the paper feed roller 6 by a spring (not shown). When the cam 5a of the cam body 5 attached to the release shaft 4 acts on the cam follower 3b provided on the push plate operation lever 3, the push plate operation lever 3 moves the push plate 21 upward in the drawing every time the paper P is fed. The actuator is operated to a pushed-up position (paper feeding state) and a position pushed down from the position (non-paper feeding state). That is, when the release shaft 4 is rotated by the start of paper feeding, the pad 6B is pressed against the paper feeding roller 6, and the push plate 21 that rotates about the push plate shaft 24 is pushed up to the paper feeding roller 6 side by the operation lever 3. Then, the leading edge of the upper layer is pressed against the paper feed roller 6.
[0013]
The sheets P on the upper layer side of the sheet feeding cassette 20 are separated one by one by the pad 6B, fed by the sheet feeding roller 6, guided by the sheet guide roller 7 and the sheet guiding unit 8, and detected by the sheet detector 9. Is sent to a conveyance unit 116 composed of the conveyance roller 10 and the driven roller 11. Subsequently, the drive control of the transport roller 10 is performed based on the paper detection to cue the paper P, and the paper P is transported to a recording area composed of the recording head 12 and the platen 13 in accordance with the recording timing. Will be discharged. Reference numeral 6A denotes an auxiliary roller for paper separation.
[0014]
Next, the paper feeding device of the present invention will be described in detail. FIG. 3 is a conceptual diagram of the paper feeding device of the present invention. The sheet feeding device is configured by a sheet conveying path in which the distance D from the sheet feeding cassette 20 to the conveying roller 10 is shorter than the length L of the sheet P. Therefore, when the leading end of the sheet P _L conveyance roller 10 is nipped, the trailing edge of the sheet P _E is in the paper feed cassette 20. When a pressing force F of a sheet side edge aligning member 27 described later acts in a direction perpendicular to the feeding direction on the rear portion of the sheet P nipped by the conveyance roller remaining in the sheet feeding cassette 20, The action becomes a rotational load of the paper feed roller 6 and the transport roller 10. When the action of the sheet side edge aligning member 27 is released during the conveyance of the sheet P, the rotational load is reduced. Such load fluctuations are particularly undesirable for the drive control system of the transport roller 10 that requires high rotational accuracy.
[0015]
Therefore, in the present invention, the sheet conveyance distance D1 from the most downstream point 27a where the pressing force F by the sheet side edge aligning member 27 acts on the sheet side edge to the conveyance roller 10 is set slightly larger than the sheet length L (D1> L ) The trailing edge of the sheet P _E is removed from the active area of the paper side edge aligning member 27, the side wall portion of the sheet side edge sheet feeding cassette 20 and the sheet end alignment member when Thereby the paper leading end P _L is nipped by the conveying roller 10 27, the paper is brought into a non-contact state (free), so that highly accurate paper conveyance is performed.
[0016]
Examples will be described below. 4 is a perspective view of the paper feeding cassette in the paper feeding device according to the present invention as viewed from the paper storage unit side, FIG. 5 is a view taken along the line II of FIG. 4, FIG. 6 is a plan view of the paper feeding cassette, and FIG. Is a rear view of the paper feed cassette, and FIG. 8 is a rear view of the paper feed cassette with the back cover removed.
[0017]
In FIG. 4, the paper feed cassette 20 forms a box-shaped container by a bottom plate portion 22 and side wall portions 23 provided on the front and rear sides and the left and right sides of the bottom plate portion 22. A push plate 21 that pushes up the stacked paper P toward the paper feed roller 6 is disposed on the front side of the paper feed cassette 20, and the push plate 21 rotates the push plate shaft 24 to the bearing portion 25 of the bottom plate portion 22. It is supported so as to be movable, and the side wall portion in front of the sheet feeding cassette 20 can move upward.
[0018]
On the rear side of the paper feed cassette 20, a pair of paper rear end abutting members 26 having contact portions 26 a that abut against the rear end of the stacked paper P are provided in parallel and spaced apart in the side wall direction. A paper side edge aligning member 27 is disposed on one side wall portion of the paper feed cassette 20 behind the push plate 21, and a plurality of convex portions 23a with which the paper side edge abuts are provided on the other side wall portion. ing. The convex portion 23 a is formed on the side wall portion 23 so as to face the paper side edge aligning member 27 behind the push plate 21.
As shown in FIG. 7, the rear portion of the paper feed cassette 20 is provided with the mechanism portions of the sheet rear end abutting member 26 and the sheet side edge aligning member 27, and a back cover 38 is attached to cover the mechanism portions. Yes.
[0019]
In FIG. 8, the paper trailing edge contact member 26 is connected to a slide plate 261 movably disposed on the back of the cassette, and a spring 262 is stretched between the slide plate 261 and the back of the cassette to supply the paper. The paper cassette 20 is biased toward the front side. The contact portion 26 a of the sheet rear end abutting member 26 has a contact surface inclined toward the rear side of the sheet feeding cassette 20 toward the bottom plate portion 22, and this contact surface is caused by the biasing force of the spring 262. To. As a result, the sheet P is pushed forward from the lower side to the lower layer side on the bottom plate side from the upper layer side, and is pressed against the side wall portion 23 of the front portion of the sheet feeding cassette 20 to feed the sheet feeding roller 6 and the pad 6B. Are fed one by one from the upper layer side.
[0020]
As shown in FIG. 6, a paper side edge aligning member 27 is disposed on one side wall side of the paper feed cassette 20 to push one side edge of the paper P and align the paper side edge with the opposite side wall part. Yes. The sheet side edge aligning member 27 includes a first pressing portion 27A and a second pressing portion 27B, and is disposed along the side wall portion. One end of each of the first push portion 27A and the second push portion 27B is linked to a bar 31 provided on the back surface of the paper feed cassette 20 to constitute a substantially intermediate portion of the paper side edge aligning member 27, and The other ends of the push portions 27A and 27B are rotatably supported by the bottom plate portion 22. One end sides of the first push portion 27A and the second push portion 27B are urged toward a side wall portion where the paper side ends are aligned by an urging mechanism 30 disposed on the back side of the paper feed cassette 20. .
[0021]
As shown in FIG. 8, the urging mechanism 30 includes a bar 31, a movable plate 32, and springs 33, 34, and 35. The bar 31 is connected to one end side of the first push portion 27 </ b> A and the second push portion 27 </ b> B, and is attached so as to be rotatable along the side wall portion of the paper feed cassette 20. The movable plate 32 is provided so as to be slidable in a direction perpendicular to the insertion direction of the paper feed cassette 20 and has a paper alignment boss 36 a on the side wall portion opposite to the side wall portion of the paper feed cassette 20. The plate 36 is integrally connected. The widened portion 36b of the boss plate 36 is guided by a plate guide portion 37 formed on the back surface of the paper feed cassette 20, and the movement of the boss plate 36 toward the bar 31 is restricted by hitting the L-shaped portion at the tip.
[0022]
A spring 33 is stretched between the bottom plate portion 22 and the movable plate 32, and a plurality of springs 34 and 35 are stretched between the bar 31 and the movable plate 32, respectively. As illustrated, the spring 33 holds the movable plate 32 by abutting the boss plate 36 against the L-shaped portion of the plate guide portion 37. At this time, the bar 31 is prevented from moving inwardly pushing the paper side edge by the extending portion 32a of the movable plate 32, and the springs 34 and 35 do not act on the bar 31. In the position shown in FIG. 6, it can be moved only outward. Since the distance between the paper side edge aligning member 27 and the side wall portion on the paper side edge align side is set slightly wider than the paper width, the paper side edge aligning member is obstructive when storing paper in the state shown in FIG. Never become.
[0023]
When the paper feed cassette 20 is mounted on the paper feed cassette mounting portion 2, the load due to the springs 34 and 35 acts by a combination of 1 or 2 in the process of inserting the paper feed cassette 20. For this purpose, the cam mechanism includes a sheet aligning boss 36a of the boss plate 36 and a rectangular groove cam 41 (see FIG. 9) provided on the bottom frame 40 of the sheet feeding cassette mounting portion 2.
[0024]
Next, the sheet side edge aligning operation when the sheet feeding cassette 20 is mounted will be described.
When the paper feed cassette 20 is inserted into the paper feed cassette mounting portion 2, the paper alignment boss 36a is guided in contact with the cam surface 41a of the groove cam 41 as shown in FIG. First, the spring 34 is actuated to push the paper side edge by the paper side edge aligning member 27. This pushing force acts from (1) in FIG. 10 to (2) in FIG. When the sheet feeding cassette 20 is continuously inserted, the spring 35 is activated, and the sheet side end is pushed by the combined load with the spring 34 in the process (2) to (3) in FIG. . The pressing force at this time becomes the largest at the position (3). Further, the paper feed cassette 20 is inserted further, and the spring 35 stops working when (4) shown in FIG. 13 is exceeded. At the position (5) in FIG. Maintain state.
By configuring the urging mechanism with the plurality of springs 34 and 35 in this manner, the force applied in the direction perpendicular to the insertion direction, which becomes a resistance when the paper feed cassette 20 is mounted, is minimized, that is, the paper side edges are aligned. You can use the power you need only when you need it.
[0025]
Since the paper feed cassette of the present embodiment is compatible with paper having slightly different vertical and horizontal sizes such as A4 size and letter size, the arrangement of the paper trailing edge contact member 26 and the paper side edge aligning member 27 is changed as shown in FIG. For this purpose, a paper rear end abutting member mounting hole 28 and a paper side edge aligning member mounting hole 29 are formed. For the arrangement of the sheet trailing edge contact member 26 and the sheet side edge aligning member 27 for various sheet sizes, for example, in the case of A4 size sheets, the mounting holes at the positions shown in FIG. The mounting holes 28 and 29 indicated by the reference numerals in the inside are used respectively.
[0026]
【The invention's effect】
According to the paper feeding device of the first aspect, since the trailing edge of the sheet is free before the leading edge of the sheet is nipped by the conveying roller, highly accurate conveyance is performed and high quality printing can be performed. Further, the printing speed can be increased and the size can be reduced by the short paper conveyance path.
[0027]
According to the paper feed cassette of claim 5, when the paper is sent out from the paper feed cassette, the predetermined length on the rear side of the paper side end in the paper feed cassette is released from the pressing by the paper side edge aligning member. Further, it is possible to reduce the load on the paper feeding system by pressing the paper side end against the side wall.
[Brief description of the drawings]
FIG. 1 is a perspective view of a printer apparatus to which a paper feeding apparatus according to the present invention is applied.
FIG. 2 is a schematic diagram of a paper feeding device in a printer device.
FIG. 3 is a conceptual diagram of a sheet feeding device according to the present invention.
FIG. 4 is a perspective view of a paper feed cassette in the paper feed device according to the present invention as viewed from the paper storage unit side.
FIG. 5 is a view taken in the direction of arrows II in FIG. 4;
FIG. 6 is a plan view of a paper feeding cassette in the paper feeding device according to the present invention. ,
FIG. 7 is a rear view of a paper feeding cassette in the paper feeding device according to the present invention.
8 is a rear view of the paper feed cassette with the back cover of FIG. 7 removed.
FIG. 9 is a diagram illustrating a relationship between a sheet alignment boss and a groove cam.
FIG. 10 is an explanatory diagram in which one spring in the sheet side edge aligning operation starts its action.
FIG. 11 is an explanatory diagram of one spring during operation in the paper side edge aligning operation.
FIG. 12 is an explanatory diagram when two springs act in the paper side edge aligning operation to align the paper side edges.
FIG. 13 is an explanatory diagram of two springs in action in the paper side edge aligning operation.
FIG. 14 is an explanatory diagram when paper-side edge alignment is completed in a state where one spring is applied in the paper-side edge alignment operation.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Printer apparatus 2 Paper feed cassette mounting part 6 Paper feed roller 10 Carrying roller 20 Paper feed cassette 21 Push plate 23 Side wall part 23a Protrusion 27 Paper side edge alignment member 27A 1st push part 27B 2nd push part 30 Energizing mechanism 31 Bar 32 Movable plate 33-35 Spring 36 Boss plate 36a Boss 40 Bottom frame 41 Groove cam 41a Cam surface P Paper

Claims (5)

A paper feed path for storing paper, a paper feed roller on the paper feed cassette side and a transport roller on the recording head side, and a distance from the paper feed cassette to the transport roller that is shorter than the paper length A paper feeding device comprising:
A paper side edge aligning member that is arranged along the side wall part and pushes and aligns the paper side edge except for a predetermined distance from the front wall part on the paper delivery side to the rear wall part side;
A plurality of springs for applying a force for urging the paper side edge to the paper side edge aligning member;
A paper alignment boss for displacing the plurality of springs, and the paper feed cassette,
When the paper feed cassette is inserted and attached to the paper feed device, a cam mechanism is configured to move the plurality of springs stepwise by displacing the paper alignment boss,
The sheet feeding device, wherein the sheet side edge aligning member is configured not to act on the sheet side edge when the leading edge of the sheet reaches the conveying roller.   2. The paper feeding device according to claim 1, wherein a plurality of protrusions for guiding the paper side edge are provided on the other side wall part facing the side wall part on which the paper side edge aligning member is disposed.   2. The biasing means according to claim 1, wherein the paper side edge aligning member includes a first pressing portion and a second pressing portion, both ends of which are axially supported, and biases both pressing portions toward the other side wall portion. Is provided.   2. The sheet feeding device according to claim 1, wherein a pressing plate that presses the leading end of the sheet against the sheet feeding roller is disposed at a position where the sheet side end aligning member in the sheet feeding cassette does not act on the sheet side end. A paper-side edge aligning member that has a side wall portion facing the paper side edge of the paper to be stored and aligns the paper side edge by pushing the paper side edge toward the opposite side wall side is disposed along the side wall portion, A region where the pressing of the paper side edge aligning member does not act on the paper side edge is provided from the front wall part on the paper side to the rear wall part side,
A plurality of springs for applying a force for urging the paper side edge to the paper side edge aligning member;
A paper alignment boss that displaces the plurality of springs,
When the paper feed cassette is inserted and attached to the paper feed device, the cam mechanism is configured to move the plurality of springs stepwise by displacing the paper alignment boss. Paper cassette to be used.

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