JP2011190029A - Medium feeding device, recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medium feeding device in which the problems of double feeding and non-feeding occurring when media to be fed have different rigidity are considered. <P>SOLUTION: The medium feeding device (2) includes an arm part 4 holding a feeding roller (3), and a part (7) of a placing part 6 opposing to at least the feeding roller (3) is displaceable in directions to come into contact with and be separated from the feeding roller (3). The medium feeding device is configured such that, when the feeding roller receives force from a medium to be fed as reaction force against force (F) acting on the medium to be fed (P) by the driving feeding roller (3), which causes the arm part 4 to rock in a direction where the feeding roller (3) approaches the medium to be fed (P), and pressing force F (F') of the feeding roller (3) against the medium to be fed (P) exceeds a predetermined amount of force (S-W), at least the part (7) of the placing part 6 is displaced. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention makes contact with a placing portion on which a feeding medium is placed and a feeding medium at the top in the stacking direction of the feeding medium placed on the placing portion, and the feeding medium is moved downstream in the feeding direction. A feeding means, and a tip that is inclined with respect to the posture of the medium to be sent placed on the placement unit as viewed from the side, and a tip that is a downstream end in the feeding direction of the medium to be sent sent by the feeding means. Separating means for separating the uppermost medium to be fed and the next and subsequent mediums with respect to the feeding means by coming into contact with the surface, and a recording apparatus having the medium feeding apparatus Relates to the device.
In the present application, the recording apparatus includes types such as an ink jet printer, a wire dot printer, a laser printer, a line printer, a copying machine, and a facsimile.

  Conventionally, as shown in Patent Document 1, an image forming apparatus as a recording apparatus includes a sheet feeding device as a medium feeding device. The sheet feeding apparatus includes a paper feed tray, a paper feed roller, and a separation slope. Among these, the sheet feeding tray is provided so that a sheet as a sheet is placed thereon. The paper feed roller is provided at the tip of the paper feed roller arm. The sheet is provided so as to be in contact with the uppermost sheet among the sheets stacked on the sheet feeding tray and to be fed to the downstream side in the feeding direction. Still further, the separation slope is inclined with respect to the posture viewed from the side of the leading end side of the placed paper, on the downstream side in the feeding direction from the leading end which is the downstream end of the paper placed on the paper feed tray. It was provided.

Here, so-called bank separation using the separation slope is a configuration that uses the stiffness of the paper, which solves both the thin paper double feed problem and the thick paper non-feed problem. It is very difficult to do.
Therefore, in the prior art, the separation slope is provided so as to be movable in the inclined direction, and is biased by a spring to the upstream side in the feed direction of the separation slope.

When the paper is thin, the stiffness of the paper is weak, so that the transport load when the leading edge of the thin paper approaches and collides with the separation slope at the first predetermined entry angle is small. This is because the thin paper is easy to bend and the leading end side of the thin paper tends to go up the separation slope. Therefore, in the case of thin paper, it collided at the predetermined entry angle, and from the time of the entry angle, the leading edge of the thin paper could start to climb the separation slope.
On the other hand, when the paper is a thick paper, the stiffness of the paper is stronger than that of the thin paper. Therefore, the transport load when the leading edge of the thick paper approaches and collides with the separation slope at the first predetermined entry angle is thin paper. Larger than the case of. This is because thick paper is less likely to bend than thin paper, and the leading end of the thick paper is less likely to go up the separation slope.

  At this time, the separation slope receives a force from the leading end of the cardboard, and moves to the downstream side in the feed direction on the separation slope against the biasing force of the spring. At this time, the position of the leading edge of the cardboard changes, but the location of contact with the leading edge on the separation slope does not change. That is, it is a state before the leading edge of the cardboard starts to rise up the separation slope. The separation slope further moves downstream in the feed direction on the separation slope. At this time, the approach angle with respect to the separation slope on the leading end side of the cardboard gradually decreases. Thereby, a conveyance load becomes small gradually. Therefore, in the case of cardboard, it was possible that the leading edge of the cardboard began to climb up the separation slope from the time when the reduced entry angle became the second predetermined angle.

JP 2001-354330 A

  However, in the above configuration, in the case of thick paper, compared to the case of thin paper, the entrance angle to the paper is reduced and the transport load is only reduced. Therefore, it was not sufficient for the problem of non-feeding of cardboard.

  The present invention has been made in view of such a situation, and the object thereof is to provide a medium feeding device and a medium feeding device that take into account the multi-feed problem and the non-feed problem when the rigidity of the medium to be fed is different. It is to provide a recording apparatus.

  In order to achieve the above object, a medium feeding device according to a first aspect of the present invention includes a placement unit on which a medium to be fed is placed, and the uppermost layer in the stacking direction of the medium to be fed placed on the placement unit. A feeding means for contacting the medium to be fed and feeding the medium to be fed downstream in the feeding direction; and a surface inclined with respect to the posture of the medium to be fed placed on the mounting portion as viewed from the side. Separating means for separating the uppermost transported medium and the subsequent transported medium with respect to the transporting means when the tip which is the downstream end in the transporting direction of the transported medium fed by the means comes into contact with the surface; The feed means is provided so as to be driven, and is a feed roller that is in contact with the medium to be fed placed on the placement unit, and is upstream of the feed roller in the feed direction, and in the stacking direction. Centered on the position above the feed roller An arm portion that rotatably holds the feed roller on the free end side, and at least a portion of the placement portion that faces the feed roller is displaceable in a direction of contact with and away from the feed roller. The feeding roller receives a force from the medium to be fed as a reaction force against the force that the driving roller to act on the medium to be fed, and swings the arm portion in a direction in which the feeding roller approaches the medium to be fed. When the force is applied and the magnitude of the force with which the feeding roller presses the medium to be fed becomes larger than the magnitude of the predetermined force, at least the part of the placement portion is configured to be displaced. It is characterized by that.

  Here, the “predetermined magnitude of force” is provided as follows. When the medium to be fed is a medium having a relatively low rigidity, the magnitude of the pressing force is equal to or less than the “predetermined force magnitude”, and the medium to be fed is a medium having a relatively high rigidity. The size of the pressing force is set to be larger than the “predetermined force”. That is, when the rigidity of the medium to be fed is higher than a predetermined value, the medium to be fed cannot move up the surface as it is. The “predetermined magnitude of force” is provided so as to be greater than the “magnitude of force”.

According to the first aspect of the present invention, it is possible to displace at least a part of the placement portion according to the rigidity of the medium to be fed.
For example, when the medium to be fed is a medium having relatively low rigidity, the magnitude of the force with which the feeding roller presses the medium to be fed is less than a predetermined force. Accordingly, the part of the mounting portion is not displaced. Therefore, the angle at which the medium to be fed enters the surface of the separating means does not change. Moreover, since the relative position and attitude | position of the said arm part and the said one part of the said mounting part do not change, the normal force produced between the said feed roller and a to-be-fed medium does not change. Accordingly, the feed force that is the force by which the feed roller feeds the medium to be fed in the feed direction does not change. As a result, the medium having low rigidity can be reliably fed as before.

  On the other hand, when the medium to be fed is a medium having a relatively high rigidity, when the downstream end of the medium to be fed comes into contact with the surface of the separating means, the reaction force is larger than that of a medium having a low rigidity. To do. As a result, the force acting on the arm portion in a swinging direction so that the leading end of the arm portion is difficult to enter between the uppermost medium to be fed is also increased. And the magnitude | size of the force with which the said feed roller presses a to-be-feeded medium becomes larger than the magnitude | size of predetermined force. At this time, at least the part of the mounting portion can be displaced by the pressing force. At this time, the position of the downstream end of the medium to be fed in contact with the surface of the separating means is not displaced.

That is, it is possible to displace the upstream side from the downstream end while keeping the position of the downstream end of the medium to be sent. Therefore, the angle at which the medium to be fed enters the surface of the separating means can be reduced. As a result, it is possible to reduce the transport load necessary for the leading end of the medium to be sent to pass through the separating means as a first effect.
Further, the vertical drag generated between the feed roller and the medium to be fed can be increased by the arm portion swinging in a direction approaching the medium to be fed. As a result, it is possible to increase a feeding force that is a force by which the feeding roller sends the medium to be fed in the feeding direction as a second effect.
Therefore, not only the low-rigidity medium but also the high-rigidity medium can be reliably sent by the first operational effect and the second operational effect.

Note that the position of the part of the mounting portion in the state before the magnitude of the force with which the feeding roller presses the medium to be fed reaches a predetermined magnitude is such that the medium to be fed having a relatively low rigidity is It is assumed that the position is provided so as to be separated by the separating means.
Moreover, the structure which the said mounting part elastically deforms and the said part displaces may be sufficient. That is, the part of the mounting portion does not need to be formed separately from the part other than the part, and may be formed integrally with the part other than the part. For example, the part and the part other than the part may be connected by a connecting part, and the connecting part may be elastically deformed and the part may be displaced.

According to a second aspect of the present invention, in the first aspect, the first medium and the second medium having higher rigidity than the first medium can be fed as the medium to be sent. In the case of the first medium, at least the part of the placement part is not displaced by the pressing force, and in the case of the second medium, at least the part of the placement part is pressed. It is the structure displaced by force, It is characterized by the above-mentioned.
According to the 2nd mode of the present invention, in addition to the same operation effect as the 1st mode, it can respond to the sending medium of different rigidity.

According to a third aspect of the present invention, in the first or second aspect, the third aspect further includes urging means for urging at least the part of the placement portion in a direction approaching the feeding roller. It is characterized by.
According to the third aspect of the present invention, in addition to the same effect as the first or second aspect, the magnitude of the force to be biased with high accuracy is set as compared with the configuration in which the connecting portion is elastically deformed. can do. In other words, the position and posture of the part of the placement unit can be managed with high accuracy.

As a result, the feeding force can be managed with higher accuracy. Similarly, the transport load can be managed with higher accuracy.
It should be noted that the position and orientation on the side approaching the feed roller in a range in which at least the part of the placement portion is displaced is determined by balancing the weight of the medium to be fed and the biasing force of the biasing means. It is possible to configure.

According to a fourth aspect of the present invention, in the third aspect, the apparatus further includes a restricting portion that restricts a position on the side approaching the feed roller in a range in which at least a part of the placement portion is displaced. It is characterized by.
According to the fourth aspect of the present invention, in addition to the same effects as those of the third aspect, in the case of a medium to be fed having low rigidity, the position of the mounting portion is not displaced, so that the approach angle is made constant. Can do.

That is, it is possible to determine a reference position of at least the part of the placement portion by the restriction portion.
Further, it is not necessary to balance the weight of the medium to be fed and the urging force of the urging means that urges the placing portion. In other words, the provision of the restricting portion increases the degree of freedom of the urging force of the urging means, and the setting of the urging force is easy. As a result, it is possible to easily cope with a case where the difference in rigidity of the medium to be fed is large.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, at least the part of the mounting portion swings around a downstream side in the feed direction. To do.
According to the fifth aspect of the present invention, in addition to the same function and effect as any one of the first to fourth aspects, when the at least part of the mounting portion is displaced, the approach angle is positively changed. Can be small. At the same time, the change in the relative posture between the arm part and the part of the mounting part is greatly increased when the arm part is swung so that the leading end of the arm part is not easily inserted into the uppermost medium to be fed. By doing so, the pressing force can be positively increased. As a result, the conveyance load can be positively reduced and the feed force can be increased.

According to a sixth aspect of the present invention, in any one of the first to fourth aspects, at least the part of the mounting portion is configured to move while maintaining a posture.
According to the sixth aspect of the present invention, in addition to the same function and effect as any one of the first to fourth aspects, the above-described fifth aspect is compared with the case of swinging around the downstream side. Setting of biasing force is easy. In addition, the change in the approach angle and the change in the relative posture can be moderated as compared with the case of swinging around the downstream side. It is possible to prevent double feeding due to a sudden reduction in the transport load and an increase in the feed force.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the mounting portion is a portion on the downstream side of the mounting portion in the feeding direction and facing the feeding roller. It is a structure which is displaced and is not displaced on the upstream side in the feed direction from the part of the placement portion.
According to the seventh aspect of the present invention, in addition to the same function and effect as in any one of the first to sixth aspects, it is possible to cope with a case where the size of the medium to be fed is different. It is very effective because the ratio of the weight of the entire fed medium affecting the urging force for urging the part of the placement portion can be reduced.

A recording apparatus according to an eighth aspect of the present invention includes a medium feeding unit that feeds a recording medium in a feeding direction, and a recording unit that records the recording medium sent by the medium feeding unit by a recording head. In the recording apparatus, the medium feeding unit includes the medium feeding apparatus according to any one of the first to seventh aspects, and the recording medium is the feeding medium. .
According to an eighth aspect of the present invention, the medium feeding means includes the medium feeding device according to any one of the first to seventh aspects. Therefore, in the recording apparatus, it is possible to obtain the same function and effect as in any one of the first to seventh aspects.

FIG. 2 is a side view illustrating the outline of the printer according to the invention. The principal part enlarged side view which shows the outline of the medium feeding means which concerns on this invention (before feeding). (A) (B) is a schematic side view which shows the state of the medium feeding means at the time of feeding thin paper. (A) (B) is a schematic side view which shows the state of the medium feeding means at the time of feeding cardboard. FIGS. 5A and 5B are side views illustrating an outline of a medium feeding unit according to another embodiment 1; FIGS. (A) (B) is a side view which shows the outline of the medium feeding means based on other Embodiment 2. FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a side view showing an outline of a printer which is an example of a recording apparatus according to the present invention.
As shown in FIG. 1, the printer 1 according to the present invention includes a medium feeding unit 2, a feeding path, a recording unit 16, and a discharging unit 20.

Among these, the medium feeding means 2 is provided so that the paper P which is an example of the medium to be fed can be fed in the feeding direction Y. The feeding path is constituted by a medium guiding unit that guides the paper P sent by the medium feeding means or the like, and indicates the path through which the paper P is sent.
The recording unit 16 is configured to perform recording on the paper P sent by the medium feeding unit 2. Furthermore, the discharge unit 20 is provided so that the recorded paper P can be discharged and placed on a discharge tray (not shown).

  Specifically, the medium feeding unit 2 includes a placing unit 6, a pickup roller 3, an arm unit 4, a separating unit 12, a first roller pair 14, and a second roller pair 15. Among these, the placement unit 6 is provided so that the paper P is placed thereon. The pickup roller 3 can be driven by the power of the motor, and is provided so as to be in contact with the paper P at the top of the stacking direction among the papers P stacked on the placement unit 6.

Furthermore, the arm portion 4 is provided so as to be swingable around a swing shaft 5 on one end side that is upstream in the feed direction. And it is comprised so that the pick-up roller 3 may be rotatably hold | maintained to the other end side which is a feed direction downstream.
The motor may be provided at a location on the base part side of the printer 1 different from the arm part 4 or may be provided on the arm part. In the former case, the power is transmitted to the pickup roller 3 through the swing shaft 5 by power transmission means such as a gear train. On the other hand, in the latter case, power is transmitted to the pickup roller 3 by power transmission means such as a gear train without passing through the swing shaft 5.

In addition, the separating unit 12 is provided on the downstream side in the feeding direction from the place where the paper P is set in the loading unit 6. Specifically, it has an inclined surface 13 that is inclined with respect to the posture viewed from the side of the paper P fed by the pickup roller 3. When the paper P is double fed, the uppermost paper P and the subsequent paper P are separated from the pickup roller 3. This is a so-called bank separation mechanism.
Here, the “bank separation mechanism” refers to a mechanism that provides a surface so that the paper P enters at a predetermined angle and separates the paper P by applying a load to the front end of the paper P.

Furthermore, the first roller pair 14 and the second roller pair 15 are provided so that the paper P that has passed through the separating means 12 can be sent to the recording unit 16. Among these, the 1st roller pair 14 has the 1st drive roller 14a and the 1st driven roller 14b.
Instead of the first driven roller 14b, a so-called retard roller with a predetermined load in rotation may be used. In such a case, when the separation by the bank separation mechanism is not sufficient, the double-fed paper P can be reliably separated. That is, the paper that is in direct contact with the first drive roller 14a can be separated from the paper on the retard roller side from the paper.

The second roller pair 15 is provided on the downstream side of the first roller pair 14 in the feed path. Specifically, the second roller pair 15 has a second drive roller 15a and a second driven roller 15b. For example, it is provided so that the paper P can be sent to the recording unit 16 with high precision by a stepping motor.
Needless to say, when the leading edge of the paper P reaches the second roller pair 15, so-called skew removal is performed to correct the posture of the paper P with respect to the feeding direction Y.

  The recording unit 16 includes a carriage 17, a recording head 18, and a medium support unit 19. Among these, the carriage 17 is configured to move in the width direction X by the power of a moving means (not shown) while being guided by a guide shaft (not shown) extending in the width direction X of the paper P. Yes. The recording head 18 is provided in the carriage 17 so that ink can be ejected onto the paper P. This is so-called ink jet recording.

Furthermore, the medium support portion 19 is provided at a position facing the recording head 18 and is configured to support the paper P and to set the distance between the paper P and the recording head 18 at a predetermined interval. ing.
In the present embodiment, the ink jet recording unit 16 that ejects ink is used, but other configurations may be used. For example, a so-called laser printer configuration may be used in which toner is attached to the paper P and recording is performed on the paper P by applying heat and pressure.

The discharge unit 20 includes a third roller pair 21 and a discharge tray (not shown). The third roller pair 21 is provided on the downstream side of the recording unit 16 in the feeding path, and is provided so that the recorded paper P can be sent to the discharge tray.
The placement unit 6 of the medium feeding unit 2 may have a so-called cassette type configuration that can be attached to and detached from the printer main body, or may be formed integrally with the printer main body.
Next, the medium feeding means 2 that is a main part of the present invention will be described in more detail.

FIG. 2 is an enlarged side view of an essential part showing an outline of the medium feeding means according to the present invention before starting feeding.
As shown in FIG. 2, the placement unit 6 has a first placement surface 7 on the downstream side in the feed direction and a second placement surface 8 on the upstream side of the first placement surface 7. Among these, the first placement surface 7 is provided at a position facing the pickup roller 3. Further, the first mounting surface 7 is provided so as to be displaceable in the contact / separation direction with respect to the pickup roller 3. In the present embodiment, the paper P is provided so as to be displaceable in the stacking direction Z of the paper P. On the other hand, the second mounting surface 8 is provided so as not to be displaced. That is, the second mounting surface 8 is fixed.

  Further, the first placement surface 7 is biased upward in the stacking direction, which is a side approaching the pickup roller 3, by a biasing force of a spring 10 which is an example of a biasing unit 9. And the position and attitude | position in the side which approaches the pick-up roller 3 in the displacement possible range of the 1st mounting surface 7 by the control member 11 are determined. In a state where the first placement surface 7 is in contact with the regulating member 11, the first placement surface 7 and the second placement surface 8 are in the same positional relationship. That is, the position in the stacking direction Z is the same.

  It is assumed that the regulating member 11 is provided so as not to hinder the feeding of the paper P. For example, the first placement surface 7 is provided wider than the range in which the paper P is provided in the width direction X of the paper P. The regulating member 11 can be provided on both sides of the first placement surface 7 in the width direction X and outside the paper P in the width direction X so that the regulating member 11 does not contact the paper P.

  Furthermore, the pickup roller 3 is provided so as to be able to press the uppermost sheet P. For example, the structure which presses with the self-weight of the pick-up roller 3 and the arm part 4 may be sufficient. Moreover, the structure pressed by the urging | biasing force of the urging means which is not shown in figure may be sufficient. A spring can be used as the biasing means. Alternatively, a configuration may be used in which a force that causes the arm 4 to swing in a direction in which the pickup roller 3 approaches the paper P is generated by a dynamic friction force generated between two relatively rotating members. A so-called torque limiter is used for the swing shaft 5.

In the present embodiment, the first placement surface 7 in which the first placement surface 7 and the second placement surface 8 are in the same positional relationship is not displaced as a reference.
And in the state before the paper P is sent, the 1st mounting surface 7 is comprised so that it may not be displaced. Specifically, when the pickup roller 3 presses the paper P, the pressing force is N, the weight of the paper P acting on the first placement surface 7 is W, and the first placement surface 7 is not displaced. If the force of the spring 10 is S,
Pressing force N + paper weight W <spring force S
The relationship is established.

In the present embodiment, although the regulating member 11 is provided, it is not always necessary to provide it. For example, at the position when the first mounting surface 7 is not displaced,
Pressing force N + Paper weight W = Spring force S
If the above relationship is established, the force relationship can be balanced, so that the position of the first placement surface 7 can be stabilized at the position when it is not displaced. In such a case, the regulating member 11 may not be provided.
In the present embodiment, the restriction member 11 is provided because the degree of freedom in setting the magnitude of the force of the spring 10 can be increased. And it is because the 1st mounting surface 7 of the state which is not displaced can be stabilized more.
[When sending thin paper (first medium)]

3A and 3B are schematic side views showing the state of the medium feeding means when feeding thin paper. Among these, FIG. 3A shows a state in which the leading edge of the thin paper is in contact with the inclined surface. On the other hand, FIG. 3B shows a state further sent from the state of FIG.
Here, “thin paper” refers to a type of paper having a relatively thin thickness and a relatively weak stiffness. This is a subordinate concept of “first medium”, which is a medium having relatively weak stiffness.

As shown in FIG. 3A, the pickup roller 3 is rotated clockwise in the drawing, so that the uppermost thin paper P1 can be sent to the downstream side in the feed direction. Here, R is a transport load that is a load for feeding the paper P downstream in the feed direction, and F is a feed force that the pickup roller 3 acts on the paper P.
The feed force F is determined by the friction coefficient μ between the pickup roller 3 and the paper P and the pressing force N by which the pickup roller 3 presses the paper P.

At this time, before the leading edge of the sheet P collides with the inclined surface 13 of the separating means 12, a frictional force acts between the uppermost sheet and the next sheet, but the frictional force is small. In other words, it is very small compared to the load when the leading edge of the paper P described later collides with the inclined surface 13 of the separating means 12. Therefore, the transport load R is small at the stage during the collision.
Then, the thin paper P1 approaches the inclined surface 13 at the approach angle θ1 and collides with the inclined surface 13.

At this time, the transport load R increases due to the collision. Here, for the top thin paper P1,
Transport load R <Feed force F
The friction coefficient μ, the inclined surface, and the like are configured so that the above relationship is established. On the other hand, for the thin paper P1 after the next,
Transport load R> Feed force F
The relationship is established. Therefore, even if the next and subsequent thin papers P1 are sent to the downstream side in the feed direction together with the uppermost thin paper P1, the leading edge of the next and subsequent thin papers P1 can be stopped at the inclined surface 13. That is, it can be separated from the uppermost thin paper P1.

  Further, as the transport load R increases when the leading end of the thin paper P1 collides with the inclined surface 13, a force acting upstream in the feed direction acts on the pickup roller 3 as a reaction force. Here, the arm portion 4 is configured to swing around the upper side in the stacking direction from the uppermost thin paper P1 on the upstream side of the pickup roller 3. Therefore, a force that swings the arm portion 4 acts in a direction in which the downstream side, which is the free end side of the arm portion 4 provided with the pickup roller 3, approaches the thin paper P1.

However, in the case of the thin paper P1, since the stiffness of the paper is weak, the magnitude of the swinging force is small compared to the case of the second medium described later. Here, the force by which the pickup roller 3 presses the thin paper P1 is increased by the swinging force. In the case of the first medium (P1), the magnitude of the increased pressing force does not exceed a predetermined magnitude (a magnitude obtained by subtracting the paper weight W from the force S of the spring 10). It is configured. That is,
Increased pressure N + Weight of paper W ≤ Spring force S
It is configured so that the relationship can be maintained.
Therefore, in the case of the thin paper P1 (first medium), the first placement surface 7 is not displaced.

As shown in FIG. 3B, since the stiffness of the paper is weak, the leading edge of the thin paper P1 is bent and goes up the inclined surface 13. That is, the separation is performed in a state where the approach angle of the thin paper P1 to the inclined surface 13 is θ1. And
Transport load R <Feed force F
Therefore, the thin paper P1 can be further sent downstream in the feed direction.
[When sending thick paper (second medium)]

FIGS. 4A and 4B are schematic side views showing the state of the medium feeding means when feeding thick paper. Among these, FIG. 4A shows a state in which the leading end of the cardboard is in contact with the inclined surface. On the other hand, FIG. 4B shows a state where the pickup roller is slightly driven from the state of FIG.
Here, “thick paper” refers to a type of paper that is thicker than thin paper and stronger than thin paper. This is a subordinate concept of the “second medium” that is stronger than the “first medium”.

As shown in FIG. 4A, when the pickup roller 3 rotates in the clockwise direction in the drawing, the uppermost thick paper P2 can be sent to the downstream side in the feed direction. Then, as in the case of the thin paper P1 described above, the tip of the thick paper P2 can collide with the inclined surface 13. The approach angle when the thick paper P2 collides with the inclined surface 13 is θ1 as in the case of the thin paper P1 described above.
Here, the difference from the case of the thin paper P1 described above is that the stiffness of the paper in the case of the thick paper P2 is stronger than that in the case of the thin paper P1.

  Therefore, the transport load R increases when the leading end of the thick paper P2 collides with the inclined surface 13, but significantly increases as compared with the thin paper P1 described above. This is because the thick paper P2 is stronger than the thin paper P1 and requires a large force to bend. In other words, the feed force increases from the time of collision until it bends, but the amount of increase is larger than that of the thin paper P1. That is, a feeding force larger than that in the case of the thin paper P1 is required.

  And the force to the upstream of a feed direction acts largely on the pick-up roller 3 as reaction force. The magnitude of the reaction force is significantly larger than that of the thin paper P1 described above. Therefore, the magnitude of the force that swings the arm portion 4 in the direction in which the downstream side, which is the free end side of the arm portion 4 provided with the pickup roller 3, approaches the thick paper P <b> 2 is also larger than that of the thin paper P <b> 1 described above. Remarkably large. That is, as a reaction force, the force acting on the arm portion 4 so as to insert the pickup roller 3 on the free end side of the arm portion 4 is significantly larger than that of the thin paper P1 described above. Therefore, the increase amount of the force with which the pickup roller 3 presses the thick paper P2 is also remarkably large.

In the case of the second medium (P2), the magnitude of the increased pressing force is larger than a predetermined magnitude (a magnitude obtained by subtracting the paper weight W from the force S of the spring 10). It is configured. That is,
Increased pressure N + Weight of paper W> Spring force S
It is comprised so that it can become a relationship.

  Therefore, as shown in FIG. 4B, the first placement surface 7 is pushed down against the force S of the spring 10. At this time, the tip of the thick paper P2 is in contact with the inclined surface 13, and the contact portion between the thick paper P2 and the inclined surface 13 is not displaced. Therefore, light deflection occurs near the tip of the thick paper P2, and the entry angle of the thick paper P2 with respect to the inclined surface 13 decreases from θ1 to θ2. Thereby, as a first effect, the transport load can be changed from R before displacement to a smaller value R ′. That is, by reducing the entry angle, the leading edge of the cardboard P2 can easily rise up the inclined surface 13 and the conveyance load can be reduced.

  Further, in a state in which the first placement surface 7 is displaced, the inclination of the arm portion 4 with respect to the paper feeding direction Y at the location where the pickup roller 3 contacts the thick paper P2 becomes large. Therefore, a force acting on the arm portion 4 so as to bite the pickup roller 3, that is, a force that the arm portion 4 tries to bite significantly acts. Therefore, the increased pressing force by which the pickup roller 3 presses the paper P can be changed from the magnitude N before displacement to N ′, which is a significantly larger value.

Here, the “force to bite” will be described. For example, let us consider a case where the pressing force N in the state where the inclination of the arm portion is different and the pickup roller is not driven is the same. In this case, the feeding force F at the time of driving increases as the inclination in the range until the arm portion 4 becomes perpendicular to the paper feeding direction Y at the location where the pickup roller 3 contacts the thick paper P2. This is because the arm portion 4 functions as a so-called wedge.
As a result, as a second function and effect, the feeding force that the pickup roller 3 acts on the thick paper P2 can be changed from F before displacement to F ′, which is a significantly larger value. That is, by significantly increasing the feeding force, the tip of the thick paper P2 can easily rise up the inclined surface 13.

In the displaced state, the force of the spring 10 becomes S ′ which is a value larger than the magnitude S before the displacement because the amount of elastic deformation is large.
And in the displaced state,
Increased pressing force N ′ + paper weight W ≧ spring force S ′
It is comprised so that it can become a relationship.

Further, in the state where the first placement surface 7 is displaced, the position of the first placement surface 7 may or may not reach the lower end in the stacking direction within the displaceable range. If so,
Increased pressing force N '+ paper weight W> spring force S'
The relationship is established. On the other hand, if it has not reached, the force relationship is balanced,
Increased pressing force N ′ + paper weight W = spring force S ′
The relationship is established.

  As described above, by adopting a configuration in which the first placement surface 7 is displaced, the uppermost sheet P can be reliably placed on both the thin paper P1 (first medium) and the thick paper P2 (second medium). The recording unit 16 can be sent via the separating unit 12. That is, there is no possibility of so-called non-feed (non-feed) that the uppermost sheet P cannot pass through the separating unit 12 in one of the thin paper P1 (first medium) and the thick paper P2 (second medium). Moreover, it is not necessary to make the inclined surface 13 of the separating means 12 into a special configuration.

In the above embodiment, the first mounting surface 7 which is a part of the mounting portion 6 can be displaced, and the second mounting surface 8 is not displaced. This is to reduce the influence of the difference in the own weight W for each paper size on the displacement of the first placement surface 7 when the paper sizes are different.
Moreover, although the 1st mounting surface 7 was set as the structure extended to the both sides of the paper P in the width direction X, it is not restricted to this. What is necessary is just to be formed in the range facing the pick-up roller 3 at least in the width direction X. This is because the inclined surface 13 is provided in a range facing the pickup roller 3.

Furthermore, although the first placement surface 7 and the second placement surface 8 are formed separately, they may be formed integrally. In this case, it is possible to configure the first mounting surface 7 to be displaced by elastically deforming the connecting portion between the first mounting surface 7 and the second mounting surface 8.
Moreover, although the spring 10 in which the magnitude of the urging force changes according to the amount of elastic deformation is used as an example of the urging means 9, the present invention is not limited thereto. As a technical idea, the urging means 9 only needs to be able to be urged, and may be configured such that the magnitude of the urging force does not change. For example, the structure which energizes by sending a wind may be sufficient. In the case of the configuration that does not change, it is easy to displace the first placement surface 7.

  In the above embodiment, two types of paper having different rigidity between the thin paper P1 and the thick paper P2 have been described as examples. However, the invention is not limited to the two types. As a technical idea, it is sufficient that the displacement amount of the first placement surface 7 is different according to the rigidity of the paper, and it is possible to deal with three or more kinds of papers having different rigidity. Specifically, when the medium is more rigid than the thick paper P2, the displacement amount of the first placement surface 7 may be larger than the displacement amount in the case of the thick paper P2. That is, if the displacement amount of the first mounting surface 7 is increased according to the rigidity of the medium, it is possible to deal with media having different rigidity. The first mounting surface 7 is not displaced when the medium has the lowest rigidity and may be displaced when the medium has the second lowest rigidity.

  The medium feeding means 2 as the medium feeding device of the present embodiment includes a placement unit 6 on which a sheet P, which is an example of a medium to be fed, and a sheet P placed on the placement unit 6 in the stacking direction. Feeding means for contacting the upper sheet P and feeding the sheet P to the downstream side in the feeding direction, and an inclined surface 13 that is inclined with respect to the posture of the sheet P placed on the loading unit 6 as viewed from the side. A separating unit 12 that separates the uppermost sheet and the next and subsequent sheets with respect to the feeding unit by a leading end that is a downstream end in the feeding direction of the sheet P fed by the feeding unit contacting the inclined surface 13; The feeding means is provided so as to be driven, and is a pickup roller 3 as a feeding roller that comes into contact with the paper P placed on the placement unit 6, and is upstream of the pickup roller 3 in the feeding direction Y. Pick-up in the stacking direction Z And an arm portion 4 that rotatably holds the pickup roller 3 on the free end side with a swing shaft 5 provided at a position above the roller 3 as a center, and at least the pickup roller in the mounting portion 6 The first mounting surface 7, which is part of the first mounting surface 7, is displaceable in the contact / separation direction with respect to the pickup roller 3, and reacts with a feeding force F as a force that the driving pickup roller 3 acts on the paper P. As a force, the pickup roller 3 receives a force from the paper P, and a force that swings the arm portion 4 in a direction in which the pickup roller 3 approaches the paper P acts. When the magnitude of (N ′) becomes larger than the magnitude of a predetermined force (spring force S−paper weight W), the first placement surface 7 of the placement portion 6 is in the stacking direction. Characterized in that it is configured so as to be displaced towards.

  In the present embodiment, the thin paper P1 that is an example of the first medium and the thick paper P2 that is an example of the second medium having higher rigidity than the thin paper P1 can be sent as the medium to be sent. In the case of thin paper P1, the first placement surface 7 of the placement portion 6 is not displaced by the pressing force N, and in the case of thick paper P2, the first placement surface 7 of the placement portion 6 is increased. The structure is characterized in that it is displaced downward in the stacking direction by pressure N (N ′).

Furthermore, in the present embodiment, it is further provided with urging means 9 that urges the first placement surface 7 of the placement portion 6 upward in the stacking direction, which is a direction approaching the pickup roller 3. And
Moreover, in this embodiment, it is further provided with the control member 11 as a control part which controls the position in the side which approaches the pick-up roller 3 in the range which the 1st mounting surface 7 of the mounting part 6 displaces. Features.

Furthermore, in this embodiment, the 1st mounting surface 7 of the mounting part 6 is the structure which moves in the state holding the attitude | position, It is characterized by the above-mentioned.
Further, in the present embodiment, the placement unit 6 is disposed on the downstream side of the placement unit 6 in the feed direction Y and the first placement surface 7 facing the pickup roller 3 is displaced. The second mounting surface 8 on the upstream side in the feed direction from the mounting surface 7 is configured not to be displaced.
A printer 1 as an example of a recording apparatus according to the present embodiment includes a medium feeding unit 2 that feeds a sheet P, which is an example of a recording medium, in a feeding direction Y, and a recording head for the sheet P sent by the medium feeding unit 2. And a recording unit 16 for recording by the number 18.
[Other embodiment 1]

5A and 5B are side views showing an outline of the medium feeding means according to another embodiment 1. FIG. Among these, FIG. 5A shows a state where the first placement surface is not displaced. On the other hand, FIG. 5B shows a state where the first placement surface is displaced.
As shown in FIGS. 5A and 5B, the first placement surface 31 of the medium feeding means 30 according to the other embodiment 1 is provided so that the upstream side can swing around the support shaft 32 on the downstream side in the feeding direction. It has been.
Since other members are the same as those in the above-described embodiment, the same reference numerals are used, and description thereof is omitted.

  Since the first placement surface 31 is configured to swing around the support shaft 32, the first placement surface 31 is more aggressively moved when the first placement surface 31 is displaced in the case of the cardboard P2 than in the embodiment described above. The angle θ2 can be reduced. That is, even if the amount of displacement on the upstream side of the first placement surface 31 is the same as that in the above-described embodiment, the approach angle θ2 can be reduced as compared with the above-described embodiment. As a result, it is possible to positively reduce the transport load R ′ as the first operational effect as compared with the above-described embodiment.

In addition, the thick paper P2 can be tilted so that the leading edge of the thick paper P2 escapes toward the side where the leading edge of the thick paper P2 goes up the inclined surface 13. Therefore, the tip of the thick paper P2 can easily climb the inclined surface 13.
At the same time, the change in the relative posture of the arm unit 4 and the first placement surface 31 when the tip of the arm unit 4 is swung so as to be difficult to fit between the uppermost thick paper P2 is increased. The biting force can be positively increased. As a result, the feed force F ′ as the second effect can be positively increased as compared with the embodiment described above.
In the case of the thin paper P1, the first placement surface 31 is not displaced, and thus the same as the case of the thin paper P1 in the above-described embodiment. The description is omitted.

In another embodiment 1, the first placement surface 31 of the placement unit 6 is configured to swing around a support shaft 32 on the downstream side in the feed direction.
[Other embodiment 2]

6A and 6B are side views showing an outline of a medium feeding unit according to another embodiment 2. FIG. Among these, FIG. 6A shows a state in which the placement surface is not displaced. On the other hand, FIG. 6B shows a state where the placement surface is displaced.
As shown in FIGS. 6A and 6B, the placement unit 6 of the medium feeding unit 40 according to another embodiment 2 has a placement surface 41.
Since other members are the same as those in the above-described embodiment, the same reference numerals are used, and description thereof is omitted.

And the mounting surface 41 is comprised so that it can displace similarly to the 1st mounting surface 7 of embodiment mentioned above. In other words, the first placement surface 7 and the second placement surface 8 (see FIGS. 2 to 4) of the above-described embodiment are integrally formed, and the second placement surface 8 is combined with the first placement surface 7. It is configured to be displaced integrally.
Therefore, similarly to the above-described embodiment, when the placement surface 41 is displaced in the case of the thick paper P2, the approach angle can be changed from θ1 to θ2, which is a smaller value.

At the same time, the arm portion 4 is swung so that the leading end of the arm portion 4 is not easily inserted into the uppermost thick paper P2, and the magnitude of the feed force is increased from F to F ′ as in the above-described embodiment. Can be.
In the case of the thin paper P1, the placement surface 41 is not displaced, and is the same as the case of the thin paper P1 in the above-described embodiment. The description is omitted. It goes without saying that the position and posture are determined by the restricting member 11 (see FIG. 2) in a state where it is not displaced.
[Other embodiment 3]

In the above embodiment, the pickup roller 3 approaches the paper P placed on the placement unit 6 and sends the paper P. In other words, the position of the pickup roller 3 is lowered as the remaining number of sheets P placed on the placement unit 6 decreases.
In other Embodiment 3, it is comprised so that a mounting part may contact / separate with respect to a pick-up roller. In such a case, the difference in the posture of the arm portion 4 can be reduced regardless of the remaining number of sheets placed on the placement portion. Therefore, the change in the pressing force N with which the pickup roller presses the paper can be reduced. As a result, the possibility of double feeding can be reduced. This is particularly effective when used only for thin paper.
The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

1 Printer, 2 Medium feeding means, 3 Pickup roller, 4 Arm part,
5 oscillating shaft, 6 mounting portion, 7 first mounting surface, 8 second mounting surface, 9 biasing means,
10 spring, 11 regulating member, 12 separating means, 13 inclined surface, 14 first roller pair,
14a 1st driving roller, 14b 1st driven roller (retard roller),
15 second roller pair, 15a second driving roller, 15b second driven roller,
16 recording section, 17 carriage, 18 recording head, 19 medium support section,
20 discharge section, 21 3rd roller pair, 30 (other embodiment 1) medium feeding means,
31 first mounting surface, 32 support shaft, 40 medium feeding means (of other embodiment 2),
41 mounting surface, F feeding force, F ′ (when the first mounting surface is displaced) feeding force,
N pressing force, N ′ pressing force (when the first mounting surface is displaced), P paper,
P1 thin paper (first medium), P2 thick paper (second medium), R transport load,
R ′ (when the first mounting surface is displaced) transport load,
S, the force of the spring (when the first mounting surface is not displaced),
S ′ Spring force (when the first mounting surface is displaced), W paper weight, X width direction,
Y feed direction, Z stacking direction (vertical direction),
θ1 approach angle (when the first mounting surface is not displaced),
θ2 Approach angle (when the first mounting surface is displaced)

Claims (8)

A placement unit on which a medium to be fed is placed;
A feeding means for contacting the medium to be fed in the stacking direction of the medium to be fed placed on the placement unit and feeding the medium to be fed downstream in the feeding direction;
A front end that is inclined with respect to the posture of the medium to be fed placed on the mounting portion as viewed from the side, and that is a downstream end in the feeding direction of the medium to be fed fed by the feeding means is in contact with the surface. Separating means for separating the uppermost fed medium and the next and subsequent fed media with respect to the feeding means,
The feeding means is provided so as to be driven, and a feeding roller that comes into contact with a medium to be fed placed on the placing section,
An arm portion that is upstream of the feed roller in the feed direction and is centered on a position that is above the feed roller in the stacking direction, and that rotatably holds the feed roller on the free end side;
At least a part of the placement unit that faces the feed roller is displaceable in a contact / separation direction with respect to the feed roller,
A force that causes the feed roller to receive a force from the medium to be fed as a reaction force against a force that the driving roller to act on the medium to be fed causes the arm to swing in a direction in which the feed roller approaches the medium to be fed. Is applied, and when the magnitude of the force with which the feed roller presses the medium to be fed is greater than the magnitude of the predetermined force, at least the part of the placement section is displaced. Feeder. The medium feeding device according to claim 1, wherein the medium feeding device is configured to feed a first medium as a medium to be fed and a second medium having higher rigidity than the first medium,
In the case of the first medium, at least a part of the mounting portion is not displaced by the pressing force,
In the case of the second medium, the medium feeding device is configured such that at least a part of the placement unit is displaced by the pressing force.   The medium feeding device according to claim 1, further comprising a biasing unit that biases at least the part of the mounting portion in a direction approaching the feeding roller.   4. The medium feeding device according to claim 3, further comprising a regulating unit that regulates a position on the side approaching the feeding roller in a range in which at least a part of the placement unit is displaced.   5. The medium feeding device according to claim 1, wherein at least a part of the placement unit swings around a downstream side in a feeding direction. 6.   5. The medium feeding device according to claim 1, wherein at least a part of the placement unit moves in a state in which the posture is maintained. 6.   The medium feeding device according to any one of claims 1 to 6, wherein the placement unit is displaced downstream in the feeding direction in the feeding direction and a part thereof facing the feeding roller is displaced, A medium feeding device having a configuration in which the upstream side in the feeding direction is not displaced from the part of the mounting portion. Medium feeding means for feeding the recording medium in the feeding direction;
A recording unit for recording with a recording head on a recording medium sent by the medium feeding means,
The medium feeding unit includes the medium feeding device according to claim 1, and the recording medium is the recording medium.

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