JP2008285307A - Automatic feeder and recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic feeder in which even if a feed roller is inclined, a retard roller follows it and can be inclined, pressing force by the retard roller can be efficiently generated and the pressing force is hardly made dispersive. <P>SOLUTION: The automatic feeder is provided with the feed roller 11 for feeding a medium to be recorded to a recording part by rotating it in such a state that the medium to be recorded is pressed to an outer peripheral surface; the retard roller 17 biased to the feed roller and having a retard fixed shaft 19; a guide bearing 27 for approachably/leavably pivotally supporting the retard fixed shaft relative to the feed roller; a biasing means 37 for biasing the retard fixed shaft in the approaching direction; and a rotation-stop means 35 for preventing rotation of the retard fixed shaft. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an automatic feeding apparatus that feeds a recording medium pressed against an outer peripheral surface of a feeding roller to a recording unit by rotation of the feeding roller, and a recording apparatus including the automatic feeding apparatus.

  2. Description of the Related Art Conventionally, an automatic feeding device that is mounted on a recording apparatus such as an ink jet printer and automatically feeds recording media one by one toward a recording unit in the recording apparatus is conventionally loaded on a feeding cassette, a feeding tray, or the like. The overlapped recording medium is pushed up from the bottom by the hopper, and the uppermost recording medium is pressed against the outer peripheral surface of the rotating feeding roller, and the recording medium is directed toward the recording unit by the rotation of the feeding roller. It is configured to be fed. However, at this time, since a plurality of recording media may be fed in an overlapped state, a separating unit is provided to prevent double feeding. As this separation means, there is one provided with a retard roller supported by a predetermined driven rotational resistance (for example, see Patent Document 1).

  In the retard roller, the roller surface of the retard roller is in press contact with the outer peripheral surface of the feeding roller, and when the recording medium is sandwiched between the feeding roller and the roller surface, the outer surface of the feeding roller and the recording medium are The friction coefficient and the pressing force of the roller surface are such that a friction force smaller than the friction force generated on the contact surface and larger than the friction force generated on the contact surface between the recording media acts on the contact surface between the roller surface and the recording medium. Etc. are set and configured.

Therefore, in a state where one recording medium is sandwiched between the outer peripheral surface of the feeding roller and the roller surface of the retard roller, the surface is covered by the frictional force of the contact surface between the outer peripheral surface of the feeding roller and the recording medium. The recording medium is fed along with the rotation of the feeding roller. On the other hand, when two or more recording media are sandwiched between the outer peripheral surface of the feeding roller and the roller surface of the retard roller, the recording medium in contact with the outer peripheral surface of the feeding roller is Although it is fed by rotation, the other recording medium is not fed together with the uppermost recording medium due to the frictional force of the contact surface between the roller surface of the retard roller and the recording medium, thereby preventing double feeding. Is done.
JP 2006-89221 A

  As shown in FIG. 7, the conventional retard roller 101 is provided on the retard holder 103, and the retard roller 103 contacts or separates from the feeding roller 107 when the retard holder 103 swings about the swing support shaft 105. Is possible. Further, one end of a spring 109 is fixed to the arm portion 108 extending from the retard holder 103, and the other end is fixed to the apparatus main body side. The action of the spring 109 causes the retard holder 103 to always move toward the feeding roller 107. It is energized.

  However, as shown in FIG. 8, when an unbalanced load is applied to the left and right of the feed roller 107 and the feed roller 107 is inclined, the swing support shaft 105 is fixed, so that the retard roller 101 is fed. It is impossible to follow the inclination of the feed roller 107, the parallelism between the feed roller 107 and the retard roller 101 is shifted, and a large pressing force is concentrated in the shoulder contact state only on the portion indicated by reference numeral 111 in FIG. As a result, the recording medium separation performance is adversely affected. In addition, there is a high possibility that the recording medium feeding skew may occur due to the shoulder contact, and in addition, the pressing force is concentrated locally, so that scratches or roller traces adhere to the recording medium, and the roller. There was a risk of uneven wear and a further decrease in transport load.

  Further, as shown in FIG. 7, the direction of the urging force of the spring 109 does not coincide with the direction of the pressing force (nip force) when the retard roller 101 is in contact with the surface of the feeding roller 107. Only a part (vector component) of the urging force of the spring 109 can be used for the generation of the pressing force, the use efficiency of the spring force is low, and variations in part dimensions directly affect the pressing force, so that the separation performance is not constant. There was a problem.

  It is an object of the present invention to allow the retard roller to follow and incline even when the feeding roller inclines, to generate the pressing force by the retard roller efficiently, and to vary the pressing force. It is an object of the present invention to provide an automatic feeding device that is difficult to perform and a recording device including the same.

  In order to achieve the above object, an automatic feeding apparatus according to a first aspect of the present invention is a feeder that feeds a recording medium to a recording unit by rotating the recording medium while being pressed against an outer peripheral surface. A feed roller, a retard roller that is biased against the feed roller and has a retard fixed shaft, a guide bearing that pivotally supports the retard fixed shaft so as to approach and separate from the feed roller, and the retard An urging means for urging the fixed shaft in the approaching direction and an anti-rotation means for preventing rotation of the retard fixed shaft are provided.

  According to the first aspect of the present invention, both ends of the retard fixed shaft can be individually moved. Therefore, when the feeding roller is tilted during the nip of the recording medium, the retard roller is also tilted following this tilt. it can. Accordingly, since the outer peripheral surface of the feeding roller and the roller surface of the retard roller are always in contact with each other in the width direction, the separation performance of the recording medium can be maintained constant and reliable separation can be realized. . In addition, the possibility of occurrence of feeding skew of the recording medium can be reduced, and in addition, the pressing force is not concentrated locally, so that scratches and roller marks adhere to the recording medium, roller uneven wear, and further conveyance. The possibility of reducing the load can be reduced.

The automatic feeding device according to a second aspect of the present invention is the automatic feeding device according to the first aspect, wherein the guide bearing extends in a normal direction at a contact point between the feeding roller and the retard roller. It is characterized by being provided.
According to this aspect, since the retard roller can approach and separate from the feeding roller in the normal direction at the contact point between them, the pressing force of the retard roller to the feeding roller can always be constant. Further, since the recording medium always proceeds in the tangent method of the feeding roller, the recording media can be stably separated from each other.

The automatic feeding device according to a third aspect of the present invention is the automatic feeding device according to the first aspect or the second aspect, wherein the urging means is a torsion coil spring, and the rotation stopping means is the rotation stopping means. One end of the torsion coil spring is configured to be engaged with both ends of the retard fixed shaft.
According to this aspect, since the one end of the torsion coil spring is configured to be engaged with both ends of the retard fixed shaft, the rotation preventing means does not need to be provided with a separate rotation stopper, thereby contributing to the reduction in the number of parts. .

The automatic feeding device according to a fourth aspect of the present invention is the automatic feeding device according to the third aspect, wherein the rotation stopping means is a groove portion formed in both end faces of the retard fixing shaft and extending in the diametrical direction. Further, one end of the torsion coil spring is engaged and configured.
According to this aspect, the both ends of the retard fixed shaft can be easily urged separately to the feeding roller by simply locking one end of each torsion coil spring to the groove portion of the retard fixed shaft. In addition, since one end of the torsion coil spring locked in the groove can prevent the rotation of the retard fixing shaft, the structure of the rotation stopping means can be simplified.

An automatic feeding device according to a fifth aspect of the present invention is the automatic feeding device according to any one of the first to third aspects, wherein the guide bearing is provided on a frame of the automatic feeding device. It is characterized by being.
According to this aspect, since the guide bearing is provided on the frame of the automatic feeding device, it is possible to contribute to the reduction of the number of parts and the miniaturization of the entire device.

  According to a sixth aspect of the present invention, there is provided a recording apparatus comprising an automatic feeding device and a recording unit that performs recording on a recording medium fed from the automatic feeding device. The feeding device is an automatic feeding device according to any one of the first to fifth aspects.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an appearance of an ink jet printer which is an example of a recording apparatus to which an automatic feeding apparatus according to the present invention is applied. FIG. 2 automatically feeds a recording medium by the automatic feeding apparatus. FIG. 3 is an enlarged side sectional view of the main part in the state, FIG. 3 is an enlarged perspective view of the main part in a state where the recording medium is automatically fed by the automatic feeding apparatus, and FIG. FIG. 5 is a sectional side view of a main portion showing an urging state of the retard roller, and FIG. 6 is a front view showing a state of the retard roller when the feeding roller is inclined. is there.

  The inkjet printer 1 is a relatively compact printer that can be carried, and a feeding cassette 7 is detachably mounted in an upper opening 5 near the rear of the printer body 3. A plurality of recording media P are accommodated in the feeding cassette 7, and the front end side of the recording media P can be pushed upward by a hopper (not shown).

  A feeding roller 11 is provided at a position facing the lower end of the feeding cassette 7. Reference numeral 9 denotes a rotating shaft 9 of the feeding roller. When the recording medium P is fed, the uppermost recording medium P pushed upward by the hopper pushing-up operation is pressed against the outer peripheral surface of the rotating feeding roller 11. As a result, feeding of the uppermost recording medium P in contact with the outer peripheral surface of the feeding roller 11 is started. As shown in FIG. 2, the recording medium P is further conveyed to the recording unit 15 at an accurate feed pitch by the action of the conveying roller 13.

  As shown in FIG. 2, a retard roller 17 having a roller surface 18 that is paired with the feed roller 11 is provided. The retard roller 17 constitutes an automatic feeding device together with the feeding roller 11 and the hopper described above. The retard roller 17 is provided with respect to the frame 20 of the automatic feeding device. As shown in FIG. 4, the retard roller 17 is provided with a retard movable shaft 21 around the retard fixed shaft 19, and a roller main body 23 is provided around the retard movable shaft 21. It has the structure which is made. The retard movable shaft 21 is rotatable around the retard fixed shaft 19 in a state where a certain rotational resistance is applied by the action of a torque generating spring 25 provided between the retard movable shaft 21 and the retard fixed shaft 19. .

  The retard roller 17 is urged with a constant urging force against the feeding roller 11 by the action of a torsion coil spring described later. The feeding of only the uppermost recording medium P by the retard roller 17 and the feeding roller 11 is performed as follows. That is, in a state where one recording medium P is sandwiched between the outer peripheral surface of the feeding roller 11 and the roller surface 18 of the retard roller 17, the contact between the outer peripheral surface of the feeding roller 11 and the recording medium P. The recording medium P is fed with the rotation of the feeding roller 11 by the frictional force of the surface. On the other hand, when two or more recording media P are sandwiched between the outer peripheral surface of the feeding roller 11 and the roller surface 18 of the retard roller 17, the recording medium in contact with the outer peripheral surface of the feeding roller 11. P is fed by the rotation of the feed roller 11, but the other recording medium is the highest recording medium due to the frictional force between the roller surface 18 of the retard roller 17 and the contact surface of the recording medium P. It is not fed with P. This prevents double feeding. The recording medium P that has not been fed is returned to the feeding cassette 7 by a medium return device (not shown).

  As shown in FIG. 5, two guide bearings 27 are formed on the frame 20 of the automatic feeding device at positions corresponding to both ends of the retard fixed shaft 19. The guide bearing 27 extends in a normal direction (indicated by reference numeral 31 in FIG. 5) at a contact point 29 between the feeding roller 11 and the retard roller 17. The diameters of both ends of the retard fixed shaft 19 are substantially equal to the width dimension of the guide bearing 27, and both ends of the retard fixed shaft 19 are respectively received in the guide bearing 27 along the normal direction 31 along the feed roller 11. Can approach and leave. The guide bearing 27 allows the both ends of the retard fixed shaft 19 to be closer to the feed roller 11 side even when the retard roller 17 is in contact with the feed roller 11 at the contact point 29 (the state shown in FIG. 5). A gap 33 is provided.

  At both ends of the retard fixing shaft 19, groove portions 35 corresponding to locking portions extending in the diameter direction are formed on the respective end surfaces. One end of a torsion coil spring 37 as an urging means is locked in each groove 35, and the other end of the torsion coil spring 37 is fixed to the frame 20 (FIG. 5). By the action of the torsion coil spring 37, both ends of the retard fixed shaft 19 are individually urged toward the feeding roller 11 side.

  Next, the operation will be described. By adopting the above configuration, both ends of the retard fixed shaft 19 can be individually moved in the guide bearing 27. Therefore, when the feed roller 11 is inclined during the nip of the recording medium P as shown in FIG. The roller 17 can also be tilted following this tilt. Accordingly, since the outer peripheral surface of the feeding roller 11 and the roller surface 18 of the retard roller 17 are always in contact with each other in the width direction, the recording medium P can be reliably separated. In addition, the possibility of occurrence of feeding skew of the recording medium can be reduced, and in addition, the pressing force is not concentrated locally, so that scratches and roller marks adhere to the recording medium, roller uneven wear, and further conveyance. The possibility of reducing the load can be reduced.

  Further, as shown in FIG. 7, in the configuration of the conventional automatic feeding device, the retard holder 103, the arm portion 108 extending from the retard holder 103 and the compression spring 109 require a large space, but a diagram using a torsion coil spring 37. The configuration of the present invention as shown in FIG. 5 does not require a retard holder and requires only a small space as a whole, so that it can be applied to a small-sized ink jet printer as shown in FIG.

1 is a perspective view showing an appearance of an ink jet printer to which the present invention is applied. The principal part expanded side sectional view of the state which is feeding the recording medium automatically with the automatic feeding apparatus. FIG. 3 is an enlarged perspective view of a main part in a state where the recording medium is automatically fed by the automatic feeding device. The front view of the retard roller which comprises the automatic feeding apparatus. The side view which shows the urging | biasing state of the retard roller. The front view which shows the state of the retard roller when a feeding roller inclines. The side view which shows the structure of the periphery of the conventional retard roller. The front view which shows the state of the conventional retard roller when a feeding roller inclines.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Inkjet printer, 3 Printer main body, 5 Upper opening, 7 Feed cassette, 9 Rotating shaft, 11 Feed roller, 13 Conveyance roller, 15 Recording part, 17 Retard roller, 18 Roller surface, 19 Retard fixed shaft, 20 Automatic Feeder frame, 21 retard movable shaft, 23 roller body, 25 torque generating spring, 27 guide rail, 29 contact point between feed roller and retard roller, 31 normal direction at contact point, 33 gap portion, 35 groove portion, 37 Torsion coil spring, P Recording medium

Claims (6)

A feeding roller that feeds the recording medium to the recording unit by rotating in a state where the recording medium is pressed against the outer peripheral surface;
A retard roller biased against the feed roller and having a retard fixed shaft;
A guide bearing that pivotally supports the retard fixed shaft so as to approach and separate from the feeding roller;
Biasing means for biasing the retard fixing shaft in the approaching direction;
An automatic feeding device comprising: rotation stopping means for preventing rotation of the retard fixed shaft.   2. The automatic feeding apparatus according to claim 1, wherein the guide bearing extends in a normal direction at a contact point between the feeding roller and the retard roller.   3. The automatic feeding device according to claim 1, wherein the biasing means is a torsion coil spring, and the rotation stopping means is configured such that one end of the torsion coil spring is engaged with both ends of the retard fixing shaft. The automatic feeding device according to claim 1, wherein:   4. The automatic feeding device according to claim 3, wherein the rotation stopping means is configured such that one end of the torsion coil spring is engaged with a diametrically extending groove formed on both end faces of the retard fixed shaft. The automatic feeding device characterized by the above-mentioned.   5. The automatic feeding apparatus according to claim 1, wherein the guide bearing is provided on a frame of the automatic feeding apparatus. 6.   A recording apparatus comprising: an automatic feeding device; and a recording unit that performs recording on a recording medium fed from the automatic feeding device, wherein the automatic feeding device is any one of claims 1 to 5. A recording apparatus, characterized in that it is an automatic feeding apparatus described in item 1.

Images