JP2002029638A - Sheet feed cassette and sheet feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feed cassette and sheet feeder capable of feeding a recording sheet without folding the angle part thereof. SOLUTION: Two angle parts of the first edge part 2 of the bottom raising plate 4 of this sheet feed cassette 2 are pressed onto a pair of slit forming bodies 3 arranged on two Y-axial edge parts side of the bottom raising plate 4, and a pickup roller 5 is arranged on the first edge of the bottom raising plate 4 of the sheet feed cassette 2. A D-type roller part 5a is arranged in the vicinity of the end of the pickup roller 5, and a roller part 5b is rotatably arranged in the part nipped by the D-type roller part 5a. A feed roller 7 and first pitch roller 8 for carrying the recording sheet are arranged in the front of the pickup roller 5. A capstan roller 9 and second pinch roller 11 for carrying the recording sheet are arranged in the front of the feed roller 7 and first pinch roller 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed cassette for stacking and holding recording paper, and a paper feeding device for supplying recording paper to a printing apparatus, a copying apparatus, and the like.

[0002]

2. Description of the Related Art FIG. 10 is a perspective view showing an example of a conventional sheet feeding apparatus disclosed in Japanese Utility Model Publication No. 3-2530.

In FIG. 10, recording papers P are stacked and held in a bundle in a box-shaped paper feed cassette 51 with no bottom. At two corners of the bundle of recording sheets P, support fittings 54b for regulating the position of the recording sheets P are provided.

[0004] The supporting bracket 54b is provided at the corner 2 of the bundle of recording paper P.
A corner separator 54 is provided so as to partially contact one of the two side surfaces, and protrudes like an eave and is arranged on the upper part of the corner of the bundle of recording paper P so as to press the recording paper P.
And the two corner separators 54 form a pair.

A pickup roller 56 having a substantially D-shaped cross section is provided above the bundle of recording sheets P so as to be able to contact and separate from the recording sheets P. Pickup roller 56
Is a rotary shaft 56a disposed so as to penetrate between the two main surfaces.
, And rotates with the rotation of the rotation shaft 56a.

[0006] In the course of the rotation of the pickup roller 56 by one rotation, the cylindrical outer peripheral surface of the pickup roller 56 comes into contact with the uppermost recording sheet P of the bundle of recording sheets P, and the cylindrical outer peripheral surface of the pickup roller 56 contacts the cylindrical outer peripheral surface of the pickup roller 56. Due to the friction with the surface of the recording paper P, a force is exerted on the uppermost recording paper P to feed the recording paper P out of the paper feed cassette 51.

On the other hand, since the two corners of the uppermost bundle of recording papers P are pressed by a pair of corner separators 54, the uppermost recording papers P are to be stopped in the paper feed cassette 51. Power also works.

However, since the frictional force between the cylindrical outer peripheral surface of the pickup roller 56 and the surface of the uppermost recording paper P is generally stronger than the rigidity of the recording paper P, the uppermost recording paper P buckles in a loop. FIG. 10 shows a state in which the recording paper P buckles in a loop shape.

The second recording paper P immediately below the uppermost recording paper P is subjected to friction between the back surface of the uppermost recording paper P and the front surface of the second recording paper P due to friction. As in the case of the recording sheet P, a force for sending the sheet out of the sheet feeding cassette 51 acts, but this force is weaker than the rigidity of the recording sheet P, and the second recording sheet P is Does not buckle.

As a result, the uppermost recording sheet P is separated from the second recording sheet P. Then, when the buckling of the uppermost recording paper P progresses and the loop portion becomes a certain size or more, the leading end of the uppermost recording paper P becomes a pair due to the restoring force of the loop portion of the uppermost recording paper P. Only the uppermost recording paper P is disengaged from the corner separator 54 and sent out of the paper feed cassette 51.

[0011]

As described above,
In the conventional sheet feeding device, the uppermost recording sheet P is buckled to be removed from the regulation by the pair of corner separators 54, and only the uppermost recording sheet P is sent out of the sheet feeding cassette 51. However, since the two corners of the uppermost recording paper P are pressed by the pair of corner separators 54, when the sheet buckles in a loop, the two corners are creased and the printing performance deteriorates. Or a fold may cause the recording paper to jam in the paper feeder.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a paper feed cassette and a paper feed device capable of feeding paper without causing a fold at a corner of a recording paper. With the goal.

[0013]

According to a first aspect of the present invention, there is provided a sheet feeding cassette for stacking and holding recording sheets, wherein the feeding direction of the recording sheets is a first direction. A direction perpendicular to the first direction in the plane is defined as a second direction, and is disposed at the bottom of the sheet cassette, the recording sheet is mounted thereon, and the recording sheet is moved with respect to the bottom of the sheet cassette. A bottom raising plate that can be held in a tilted state, and a pair of slit forming bodies respectively disposed at two corners of an edge of the sheet feeding cassette in the first direction. The slit forming body is an eaves portion that protrudes like an eave above two corners of the first edge in the first direction of the bottom raising plate, and faces an end surface on the first edge side. To restrict the movement of the recording paper in the first direction. , Between the eaves portion, and a stopper portion for forming a slit-shaped gap along the second direction, respectively.

According to a second aspect of the present invention, in the paper feed cassette, the slit forming member can pass the slit-shaped gap at the same time in a state where the two recording papers are stacked, but three The dimensions are set so that they cannot pass simultaneously in the stacked state.

According to a third aspect of the present invention, in the paper feed cassette, the bottom-up plate is rotatably supported at a second edge of the bottom-up plate opposite to the first edge. At the same time, in a state where the recording paper is mounted, the recording paper is urged to press two corners of the edge in the first direction with the eaves of the slit forming body.

According to a fourth aspect of the present invention, there is provided the sheet feeding device.
A sheet feeding device to which a sheet feeding cassette for stacking and holding recording sheets is detachably attached, wherein the sheet feeding unit sends out the recording sheets from the sheet feeding cassette and conveys the sent out recording sheets; and A paper guide that partially covers the transport mechanism and guides the recording paper during transport, wherein a direction in which the recording paper is sent is a first direction, and a direction perpendicular to the first direction in a plane is a fourth direction. 2, the paper guide is adjacent to the edge of the paper cassette on the side from which the recording paper is taken out with the paper cassette attached, and the paper guide is fed to the wall surface of the edge. A slope inclining at a predetermined angle in the direction, wherein the length of the slope in the second direction is longer than the length of the recording paper in the second direction, and the predetermined angle On the recording paper When the recording paper buckles in a loop due to the reaction force that the recording paper receives from the inclined part by applying force, the leading end of the recording paper is seated in a direction of rising from the inclined part. The angle is set to bend.

According to a fifth aspect of the present invention, there is provided a sheet feeding device.
The transport mechanism is provided so as to be able to contact and separate from the recording paper stacked and held in the paper feed cassette, and has a cylindrical portion and a planar portion so that the cross-sectional shape is substantially D-shaped. A pickup roller having a pair of D-shaped roller portions fixedly disposed at predetermined intervals on the rotating shaft, and disposed so as to face forward of the pickup roller in the paper feeding direction. A feed roller and a first pinch roller for nipping and cooperatively transporting the recording paper, and disposed in front of the feed roller and the first pinch roller in a paper feed direction, Capstan roller for holding and cooperating the
And a pinch roller.

According to a sixth aspect of the present invention, there is provided a sheet feeding device comprising:
The pickup roller further has a circular cross-sectional roller portion rotatably supported on a rotating shaft between the pair of D-shaped roller portions, and the radius of the roller portion is the D-shaped roller. The dimension is set smaller than the radius of the cylindrical portion of the portion, but larger than the dimension from the center of the D-shaped roller portion to the planar shape portion.

According to a seventh aspect of the present invention, there is provided a sheet feeding device comprising:
The capstan roller is disposed at a predetermined interval on a cylindrical outer peripheral surface of a rotation shaft thereof, and has a pair of projection regions in which a plurality of spike-shaped projections are formed. The capstan roller has a pair of roller portions at portions corresponding to the pair of protrusion regions.

[0020] The paper feeder according to claim 8 of the present invention is characterized in that:
The pair of roller portions of the second pinch roller are made of resin or metal.

According to a ninth aspect of the present invention, there is provided a sheet feeding device, comprising:
A width dimension of each of the pair of roller portions of the second pinch roller is larger than a width dimension of each of the pair of protrusion regions of the capstan roller.

According to a tenth aspect of the present invention, there is provided a paper feeding apparatus, wherein the paper feeding cassette according to the first aspect is used as the paper feeding cassette, and the first end of the raised plate in the first direction is provided. There is further provided a lever which engages the edge and pushes down the bottom raising plate so as to release the inclination of the bottom raising plate.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a sheet cassette and a sheet feeding apparatus according to the present invention will be described below with reference to FIGS.

<1. Configuration of Paper Feed Cassette> FIG. 1 is a perspective view showing the configuration of a paper feed cassette 2 for stacking and holding recording paper. In the following, orthogonal X axis, Y axis,
The Z axis is assumed for convenience. The recording paper is fed in the X-axis direction, the axis orthogonal to the X-axis in the plane is the Y-axis, and the height direction of the case 2a is the Z-axis. this is,
The same applies to FIGS. 2, 4 and 5.

As shown in FIG. 1, a paper feed cassette 2 includes a recording paper (not shown) in a rectangular box-shaped case 2a having a bottom and no lid.
Are stacked and held, and can be attached to and detached from a printing apparatus, a copying apparatus, or the like (hereinafter, referred to as an apparatus main body) while holding the recording paper.

At the bottom of the case 2a, there is provided a bottom-up plate 4 on which recording paper is mounted and which holds the recording paper in an inclined state with respect to the bottom of the case 2a. Bottom plate 4
Has a size to partially cover the bottom of the case 2a, and is rotatably supported by a rotation shaft 4a disposed on the bottom of the case 2a.

Here, the two edges of the bottom raising plate 4 in the X-axis direction are set to the first side on which the pair of slit forming bodies 3 are disposed.
If the side on which the rotating shaft 4a on the opposite side is disposed is defined as a second edge, the rotating shaft 4a is provided at the second edge in the X-axis direction. It is arranged so as to engage with a predetermined engaging portion and make the Y-axis direction the axis. Therefore, the rotating shaft 4a
By rotating the bottom-up plate 4 about the bottom, the bottom-up plate 4 can be inclined with respect to the bottom of the case 2a.

An elastic member (not shown) (for example, a coil spring) is provided between the first edge of the bottom-up plate 4 in the X-axis direction and the bottom of the case 2a. The edge is urged in the Z-axis direction.

Then, the bottom raising plate 4 urged in the Z-axis direction
The two corners of the first edge are pressed against a pair of slit forming bodies 3 respectively disposed on the two edges of the bottom-up plate 4 in the Y-axis direction when the recording paper is not mounted. Will be done. When the recording paper is stored in the paper feed cassette 2, the two corners of the edge of the recording paper are pressed against the slit forming body 3.

The slit forming body 3 includes an eaves portion 3b projecting over the corner of the first edge of the bottom-up plate 4 in the X-axis direction, and an eaves-like portion 3b. Is disposed so as to face the end surface on the side of the recording medium, to restrict the movement of the recording paper in the X-axis direction, and to form a slit-shaped gap GP between the recording paper and the eaves 3b.
Is formed.

The eaves 3b and the stopper 3c are
The elongate support plate 3d disposed outside the edge in the Y-axis direction of the bottom raising plate 4 extends from two adjacent end surfaces of the first edge in the longitudinal direction. The support plate 3d is disposed so that its main surface faces the side surface in the Y-axis direction of the case 2a, and the second end of the support plate 3d opposite to the first end edge in the longitudinal direction. The edge is rotatably supported by the rotating shaft 3a.

The rotating shaft 3a is provided so as to penetrate the main surface of the support plate 3d with the Y-axis direction as an axis, and by rotating the support plate 3d about the rotating shaft 3a, It can follow the rotation of the bottom raising plate 4.

Here, the slit width of the gap GP formed between the eaves portion 3b and the stopper portion 3c can pass when two sheets of recording paper are stacked, but cannot pass when three sheets of recording paper are stacked. It is set to such a width dimension. Therefore, the slit width of the gap GP must be changed according to the thickness of the recording paper to be stored, but the change can be dealt with by replacing the slit forming body 3.

<2. Configuration of Paper Feeding Device><2-1. Transport Mechanism> First, the transport mechanism for the recording paper of the paper feeding device 100 will be described with reference to FIGS. FIG. 2 is a perspective view showing a state in which the sheet feeding cassette 2 is attached to the sheet feeding device 100, and illustration of recording paper guide means and the like is omitted to clarify the transport mechanism.

In FIG. 2, an upper portion of the first edge in the X-axis direction of the bottom raising plate 4 of the sheet feeding cassette 2 can be brought into contact with and separated from recording paper (not shown) which is stacked and held. , A pickup roller 5 is provided.

The pickup roller 5 is disposed with the Y-axis direction as an axis, that is, parallel to the short side of the sheet cassette 2, and has a cross-sectional shape substantially in the vicinity of the left and right ends on the axis of the pickup roller 5. A D-shaped D-shaped roller portion 5a is provided. The D-type roller unit 5 a is fixedly disposed on the shaft, and rotates with the rotation of the pickup roller 5.

A roller portion 5b is rotatably disposed in a portion between the pair of left and right D-shaped roller portions 5a on the axis of the pickup roller 5.

The cross-sectional shape of the roller portion 5b is circular, and its radius is smaller than the radius of the cylindrical portion of the D-shaped roller portion 5a, but is larger than the dimension from the center of the D-shaped roller portion 5a to the planar shape portion. Therefore, the D-shaped roller portion 5a and the roller portion 5b are arranged on the pickup roller 5, and when viewed from the axial direction, the roller portion 5a is shifted from the planar shape portion of the D-shaped roller portion 5a.
Part of b appears to protrude.

The drive means of the pickup roller 5 includes a motor 6a, a worm gear 6b, an idle gear 6c, and a drive gear 6 fixedly disposed on the axis of the pickup roller 5.
d. Further, the sensor 6e is driven by a driving gear 6d.
Is arranged so as to cover a part of the edge of the drive gear 6d, the rotation angle of the drive gear 6d is detected in a non-contact manner, and the rotation of the motor 6a is controlled.

When the recording paper feed direction is referred to as a forward direction, a feed roller 7 for transporting the recording paper is provided in front of the pickup roller 5 and is pressed against the feed roller 7 to be rotatably supported. A first pinch roller 8 is provided and cooperates with the feed roller 7 to sandwich and transport the recording paper. Note that the feed roller 7 and the first pinch roller 8 are disposed with the Y-axis direction as an axis.

Further, in front of the feed roller 7 and the first pinch roller 8, a capstan roller 9 for transporting the recording paper, and a second capstan roller 9 which can be freely moved toward and away from the capstan roller 9 and is rotatably supported. Two pinch rollers 11 are provided.

Here, the configuration of the capstan roller 9 and the second pinch roller 11 will be described with reference to FIG. The capstan roller 9 is located near the left and right ends on its axis.
There is a projection region 9a in which a plurality of spike-shaped projections SP are formed on the outer peripheral surface of the cylinder.

On the other hand, the second pinch roller 11 has a roller portion 11a at a portion corresponding to the projection region 9a of the capstan roller 9. The width of the roller portion 11a is wider than the width of the projection region 9a of the capstan roller 9, and the projection region 9a of the capstan roller 9 is formed.
When the roller portion 11a is pressed against the recording paper 1a, the recording paper 1 can be reliably held and conveyed.

The width of the pair of roller portions 11a of the second pinch roller 11 is smaller than the width of the pair of projection regions 9a of the capstan roller 9, as in the case of the second pinch roller 11.
The projections at both end edges of the pair of projection regions 9a of the capstan roller 9 do not penetrate the recording paper 1 sufficiently deeply, and the recording paper 1 at that portion is pushed up, and the second pinch roller of the recording paper 1 is pressed. The portions corresponding to the both ends of the pair of roller portions 11a are not creased, and the quality of printing does not deteriorate.

Further, since the material of the roller portion 11a is made of resin or metal, the plasticizer of the rubber material adheres to the surface of the recording paper as compared with the case where the roller portion is made of a rubber material. No dye or ink adhered to the rubber material from the surface of the recording paper and transferred to the surface of the recording paper again, thereby deteriorating the print quality.

The drive means for the feed roller 7 and the capstan roller 9 includes a stepping motor 10a, a first idle gear 10b, a second idle gear 10c, and a drive gear 10 fixedly disposed on the capstan roller 9.
d, third idle gear 10e, fourth idle gear 1
0f, a drive gear 10g fixedly arranged on the feed roller 7.

The second pinch roller 11 is rotatably supported at both ends by a support plate 12.
The pair of support plates 12 each have the second pinch roller 1
One end of a spring 13 that presses 1 to the capstan roller 9 is connected. The member to which the other end of the spring 13 is connected is omitted to clarify the transport mechanism.

Although not directly contributing to the conveyance of the recording paper, a lever for separating the bottom raising plate 4 from the pressure contact state with the slit forming body 3 is provided in front of the feed roller 7 and the first pinch roller 8. 14 is provided with a lever drive mechanism. The lever drive mechanism includes a shaft 15, a second cam member 15b, and the like, which are arranged with the Y-axis direction as an axis. The detailed configuration will be described below with reference to FIG.

<2-2. Lever Drive Mechanism> FIG. 4 is a perspective view mainly showing the lever drive mechanism, and other components are omitted. In FIG.
A protruding piece 4b that engages with the lever 14 is disposed at the first end edge in the axial direction, and the lever 14 pushes down the protruding piece 4b, so that the bottom-up plate 4 urged in the Z-axis direction can be moved. It can be separated from the pressure contact state with the slit forming body 3.

The lever driving mechanism includes a projecting piece 4 of the lever 14.
b, a second cam 15b in contact with the edge opposite to the side engaging with the shaft b, a shaft 15 on which the cam 15b is fixedly mounted on the shaft, and a shaft provided on both ends of the shaft 15, respectively. 15 and a pair of first cams 15a for bringing the second pinch roller 11 (see FIG. 2) into and out of contact with the capstan roller 9 via the support plate 12, and a driving gear 15c for rotating the shaft 15. In addition, a rotation angle of the shaft 15 is
Sensor flags 15d for detection by 7
Are fixedly arranged.

As a driving means of the shaft 15, a motor 16a, a worm gear 16b attached to a rotating shaft of the motor 16a, and a first idle gear 16c connected to the worm gear 16b are connected to the first idle gear 16c. It has a second idle gear 16d, and the second idle gear 16d transmits torque to the drive gear 15c.

The shaft 15 obtained by the sensor 17
The rotation of the motor 16a is controlled based on the information on the rotation angle of the motor 16a.

<2-3. Recording Paper Guide> Next, the configuration of the recording paper guide will be described with reference to FIG. FIG. 5 is a perspective view showing a state in which recording paper is loaded on the paper supply cassette 2 and attached to the paper supply device 100.
2 shows a paper guide 18 as a guide means. In FIG. 5, the pickup roller 5 (see FIG. 2) disposed above the edge portion of the sheet cassette 2 is omitted for convenience.

The paper guide 18 sandwiches the recording paper 1 sent out from the paper feed cassette 2 toward the feed roller 7 by the pickup roller 5 (see FIG. 2) between the feed roller 7 and the first pinch roller 8. This is a configuration for guiding the recording paper 1 when feeding the recording paper 1 in the direction of the capstan roller 9.

The paper guide 18 is adjacent to the first edge of the sheet feed cassette 2 in the X-axis direction, that is, the edge on the side from which the recording sheet 1 is taken out. Inclined portion 18 inclined at a predetermined angle in the paper feeding direction with respect to the wall surface
a.

A first pinch roller 8 is disposed above the flat portion 18b following the inclined portion 18a, and a part of the feed roller 7 facing the first pinch roller 8 is an opening of the flat portion 18b. It is arranged so as to protrude from.

The length of the inclined portion 18a in the Y-axis direction is configured to be longer than the length of the recording paper 1 in the Y-axis direction, that is, the length of the short side. 2 (see FIG. 2), the recording paper 1 sent from the paper feed cassette 2 in the direction of the feed roller 7 comes into contact with the inclined portion 18a, and the recording paper 1 is formed into a loop shape by the reaction force received from the inclined portion 18a. When buckling, the recording paper 1
At which the front end of the paper feed cassette can buckle the inclined portion 18a in an upward direction, for example, 5 degrees to 30 degrees with respect to the wall surface (vertical surface) of the first edge of the sheet cassette (with respect to the horizontal plane). Is set to an angle of about 60 to 85 degrees). This angle varies depending on the thickness of the recording paper. When the recording paper is thick, a relatively gentle slope paper guide is used, and when the recording paper is thin, a relatively steep slope paper guide is used. Will be.

Then, following the flat portion 18b, the flat portion 1
8b has an inclined portion 18c which is inclined at a predetermined angle in the paper feeding direction. The inclined portion 18 c guides the recording paper 1 sent from the feed roller 7 and the first pinch roller 8 in the direction of the capstan roller 9, and
In the wrong direction.

<3. Operation of Paper Feeding Apparatus> Next, FIGS.
The operation of the sheet feeding device 100 will be described with reference to FIG. FIG.
9 are diagrams illustrating a configuration of a first end portion of the sheet feeding cassette 2 in the X-axis direction and a main portion of the sheet feeding device 100 related to sheet feeding.

First, as shown in FIG. 6, the pickup roller 5 rotates in the direction of arrow A, and the outer peripheral surface of the cylindrical portion of the D-type roller portion 5a of the pickup roller 5 is stacked and held on the recording paper. When the sheet comes into contact with the uppermost surface of the recording paper 1a of the bundle, the friction between the outer peripheral surface of the cylindrical portion and the surface of the recording paper 1a causes a force for feeding the recording paper 1a in the direction of arrow B to be recorded. Work on paper 1a.

As a result, the leading end of the recording paper 1a passes through the gap GP of the slit forming body 3. At this time, the second recording paper 1b immediately below the recording paper 1a is fed in the direction of arrow B in the same manner as the recording paper 1a due to the friction between the back surface of the recording paper 1a and the surface of the recording paper 1b. And the recording paper 1a passes through the gap 3b. In addition, 3 directly below the recording paper 1b
In some cases, a force for sending the recording paper 1c together with the recording papers 1a and 1b in the direction indicated by the arrow B also acts on the first recording paper 1c. However, the gap GP of the slit forming body 3 (in a state where two recording papers are stacked) Have an interval that can pass through) and cannot pass through.

As a result, only the leading ends of the recording sheets 1a and 1b come into contact with the inclined portion 18a of the paper guide 18. Of course, only the recording paper 1a may pass through the gap GP of the slit forming body 3, but here, it is assumed that the recording papers 1a and 1b pass.

In this state, the lever 14 is not engaged with the protruding piece 4b of the bottom raising plate 4, and the bottom raising plate 4 holds the bundle of the recording paper 1 between the eaves 3b of the slit forming body 3. In a state of being pressed against.

Next, as shown in FIG. 7, a reaction force acts on the recording papers 1a and 1b contacting the inclined portion 18a from the inclined portion 18a, and the recording papers 1a and 1b are kept in contact with the inclined portion 18a. However, the D-type roller portion 5a continues to rotate, and the frictional force between the outer peripheral surface of the cylindrical portion of the D-type roller portion 5a and the surface of the recording paper 1 (including 1a and 1b) is reduced. Is stronger than the rigidity of the recording paper 1a, the recording paper 1a buckles in a loop shape due to the reaction force applied to the uppermost recording paper 1a from the inclined part 18a. Since it is set so as to buckle in the rising direction, the leading end of the recording paper 1a rises up the inclined portion 18a.

The second recording paper 1b includes the recording paper 1
a due to friction between the back surface of the recording paper 1a and the front surface of the recording paper 1b.
a, a force for buckling acts, but this force is weaker than the rigidity of the recording paper 1 (including 1a and 1b).
b does not buckle, and the recording paper 1a and the recording paper 1b separate from each other. As a result, the recording paper 1b does not buckle in a loop with the recording paper 1a, cannot rise up the inclined portion 18a, and stops at a position in contact with the inclined portion 18a.

Accordingly, with the rotation of the D-type roller portion 5a, only the recording paper 1a is conveyed to the position of the feed roller 7, and is nipped by the feed roller 7 and the first pinch roller 8.

The recording paper 1a is conveyed to the feed roller 7 during a period until the pickup roller 5 completes one rotation and stops, and as shown in FIG. 8, after the rotation of the pickup roller 5 is stopped, the recording paper 1a is stopped. Is nipped by the feed roller 7 and the first pinch roller 8 and further conveyed as the feed roller 7 rotates.

After the rotation of the pickup roller 5 is stopped, the surface of the recording paper 1a is conveyed while being in contact with the roller portion 5b of the pickup roller 5, and the recording paper 1a is conveyed.
No contact is made with the planar shape portion a. Therefore, no frictional force is generated on the surface of the recording paper 1a in the direction opposite to the conveyance direction, and when the recording paper is nipped and conveyed by the feed roller 7 and the first pinch roller 8, the capstan rollers 9 and The transport load when the recording paper 1a is nipped and transported by the second pinch roller 11 can be reduced.

As shown in FIG. 8, after the pickup roller 5 completes one rotation and stops, the shaft 15 (FIG.
4), the cam 15b rotates to change the inclination of the lever 14, and the lever 14 is moved to the bottom plate 4 of the sheet cassette 2 by the driving means (including the configuration of reference numerals 16a to 16d shown in FIG. 4).
The bottom raising plate 4 is lowered by engaging with the protruding piece 4b of the recording paper 1b, and the pressure contact state between the back surface of the recording paper 1a and the front surface of the recording paper 1b is released.

For this reason, the recording paper 1a is
When the paper is nipped and conveyed by the first pinch roller 8, no frictional force acts between the back surface of the recording paper 1a and the front surface of the second recording paper 1b.

In FIG. 8, the slit forming member 3 is omitted in order to clarify the contact between the recording paper 1a and the roller portion 5b. This is the same in FIG. 9 described below.

Next, as shown in FIG. 9, when the recording paper 1a is conveyed to the capstan roller 9 by the rotation of the feed roller 7, the driving means of the shaft 15 (see FIG. 4) (reference numeral 16a shown in FIG. 4) 16d), the cam 15a rotates, the second pinch roller 11 moves down by the operation of the spring 13 (see FIG. 2) and the support plate 12, and the capstan is sandwiched between the recording paper 1a. It is pressed against the roller 9.

In other words, the second surface of the recording paper 1a
The roller portion 11a made of resin or metal of the pinch roller 11 is pressed into contact with the pinch roller 11, and as a result, a spike-shaped projection region 9a formed on the cylindrical outer peripheral surface of the capstan roller 9 is formed on the back surface of the recording paper 1a. The projection SP pierces,
The capstan roller 9 can convey the recording paper 1a while securing a sufficient gripping force.

As shown in FIG. 3, the width of the roller portion 11a of the second pinch roller 11 is a spike-shaped projection S.
Since the protrusions 9a are formed wider than the width of the protrusions 9a, all the protrusions SP formed in the protrusions 9a surely pierce the back surface of the recording paper 1a.

Thereafter, the recording paper 1a is conveyed while being pressed and held between the capstan roller 9 and the second pinch roller 11. Note that the subsequent transport direction is not limited to one direction. For example, when the present invention is applied to a printer of a dye thermal transfer system, a sheet coated with three dyes of yellow, magenta, and cyan is applied. Since the transfer is performed by repeatedly contacting the recording paper, the recording paper 1 is reciprocated.

[0076]

According to the paper feed cassette according to the first aspect of the present invention, the recording paper is inclined with respect to the bottom of the paper feed cassette by the bottom raising plate, and the recording paper is pushed out from the slit-shaped gap in that state. By applying the external force as described above, the recording paper can be fed without the two corners of the edge in the first direction being bent.

According to the paper feed cassette according to the second aspect of the present invention, the interval between the slit-shaped gaps of the slit forming body can simultaneously pass when two recording papers are stacked, but three slits are stacked. When the external force is applied to push the recording paper out of the slit-shaped gap, the topmost recording paper and the second recording paper immediately below it are slit. Although it is possible to pass in a state where the slit-shaped gap of the formed body is laminated, the third recording sheet immediately below the second recording sheet cannot pass because it is blocked by the slit-shaped gap. It is possible to prevent the recording papers below the first sheet from being fed simultaneously.

According to the paper feed cassette according to the third aspect of the present invention, the recording paper is inclined with respect to the bottom of the paper feed cassette, and the two corners of the edge of the recording paper in the first direction are formed. By pressing against the eaves of the slit forming body, the recording paper can be smoothly fed. Further, since the bottom raising plate is rotatably supported at the second edge, when increasing or decreasing the recording paper, the force for pressing the recording paper against the eaves of the slit forming body while changing the inclination angle is kept constant. Can be kept.

According to the paper feeding device of the fourth aspect of the present invention, the length of the inclined portion of the paper guide in the second direction is longer than the length of the recording paper in the second direction. ,
The entire leading edge of the recording paper comes into contact with the slope and buckles in a loop.The inclination angle is the angle at which the leading edge of the recording paper buckles in the direction of rising from the slope when the recording paper buckles in a loop. , The recording paper sent from the paper feed cassette can be smoothly guided to the transport mechanism.

According to the paper feeding apparatus of the fifth aspect of the present invention, an external force is applied to the recording paper stacked and held on the paper feeding cassette by the D-shaped roller portion of the pickup roller, and the recording paper is sent out. The recording paper is nipped by the feed roller and the first pinch roller and transported toward the capstan roller, and the recording paper is further transported by the capstan roller and the second pinch roller.

According to the paper feeding device of the sixth aspect of the present invention, the radius of the roller portion is smaller than the radius of the cylindrical portion of the D-shaped roller portion, but is smaller than the center of the D-shaped roller portion. When the cylindrical portion is not in contact with the recording paper, the rotatable roller contacts the recording paper, and the flat-shaped portion of the D-type roller is used for recording. Since the recording paper does not come into contact with the surface of the recording paper, no frictional force is generated on the surface of the recording paper in a direction opposite to the conveying direction, and when the recording paper is nipped and conveyed by the feed roller and the first pinch roller, the capstan The transport load when the recording paper is nipped and transported by the roller and the second pinch roller can be reduced.

According to the paper feeder of the present invention, the capstan roller has a pair of projection regions formed with a plurality of spike-like projections, and the second pinch roller is a capstan roller. Has a pair of rotatable rollers at portions corresponding to the pair of projection regions, so that the recording paper is pierced with spike-shaped projections in the projection region, and the capstan roller is sufficient for the recording paper. It can be transported while securing the grip force.

According to the paper feeder of the present invention, since the pair of roller portions of the second pinch roller is made of resin or metal, the roller portion is made of rubber material or the like. Compared to the case where the plasticizer of the rubber material adheres to the surface of the recording paper, or the dye or ink attached to the rubber material reversely transfers from the surface of the recording paper to the surface of the recording paper again, and printing The quality does not deteriorate.

According to the sheet feeding apparatus of the ninth aspect of the present invention, each width of the pair of roller portions of the second pinch roller is larger than each width of the pair of projection regions of the capstan roller. Since the width of the pair of roller portions of the second pinch roller is narrower than the width of the pair of projection regions of the capstan roller, each of the pair of projection regions of the capstan roller is The recording paper at that portion is pushed up without the protrusions at both end portions penetrating the recording paper sufficiently deeply, and the recording paper is moved to portions corresponding to both end edges of the pair of roller portions of the second pinch roller. The print quality is not degraded due to the fold.

According to the sheet feeding device of the tenth aspect of the present invention, the bottom raising plate is engaged with the first edge of the bottom raising plate in the first direction to release the inclination of the bottom raising plate. It further includes a lever that pushes down.After the pickup roller stops, the operation of the transport mechanism and the drive mechanism of the lever is combined so that the lever pushes down the bottom-up plate, so that the pickup roller is stopped and then transported by the feed roller. Since the pressed state between the recording paper and the other recording paper is released, friction between the two can be eliminated, and the transport load can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of a paper feed cassette according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a configuration of a sheet cassette and a sheet feeding device according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating a configuration of a capstan roller and a second pinch roller of the sheet feeding device according to the embodiment of the present invention.

FIG. 4 is a perspective view illustrating a configuration of a lever driving mechanism of the sheet feeding device according to the embodiment of the present invention.

FIG. 5 is a perspective view illustrating a configuration of a paper guide of the sheet feeding device according to the embodiment of the present invention.

FIG. 6 is a diagram illustrating a transport operation of the sheet feeding device according to the embodiment of the present invention.

FIG. 7 is a diagram illustrating a transport operation of the sheet feeding device according to the embodiment of the present invention.

FIG. 8 is a diagram illustrating a transport operation of the sheet feeding device according to the embodiment of the present invention.

FIG. 9 is a diagram illustrating a transport operation of the sheet feeding device according to the embodiment of the present invention.

FIG. 10 is a perspective view illustrating a configuration of a conventional sheet feeding device.

[Explanation of symbols]

1 recording paper, 2 paper cassette, 3 slit forming body,
4 bottom raising plate, 5 pickup roller, 7 feed roller, 8 first pinch roller, 9 capstan roller, 11 second pinch roller, 14 lever, 18
Paper guide, GP gap.

Claims (10)

[Claims] 1. A paper feed cassette for stacking and holding recording paper, wherein a feeding direction of the recording paper is a first direction, and a direction perpendicular to the first direction in a plane is a second direction. A bottom-up plate disposed at the bottom of the paper cassette, mounted with the recording paper, and capable of holding the recording paper in an inclined state with respect to the bottom of the paper cassette; A pair of slit forming bodies disposed at two corners of the edge in the first direction, respectively, wherein the pair of slit forming bodies is the first of the bottom raising plate.
An eaves projecting like an eave above two corners of the first edge in the direction of the first edge is disposed so as to face an end surface on the side of the first edge, and A sheet feed cassette which has a stopper portion for regulating movement in a first direction and forming a slit-shaped gap along the second direction between the sheet cassette and the eave portion. 2. The slit forming body is configured such that the interval between the slit-shaped gaps is set to a size that can simultaneously pass when two recording papers are stacked, but cannot simultaneously pass when three recording papers are stacked. Claim 1
Paper cassette described. 3. The bottom-up plate is rotatably supported at a second edge of the bottom-up plate opposite to the first edge, and is provided with the recording paper mounted thereon. 2. The paper feed cassette according to claim 1, wherein two corners of the edge in the first direction of the recording paper are urged so as to press against the eaves of the slit forming body. 3. 4. A paper feeder to which a paper feed cassette for stacking and holding recording paper is detachably attached, wherein the recording paper is sent out from the paper feed cassette,
A transport mechanism for transporting the fed recording paper, and a paper guide that partially covers the transport mechanism and guides the recording paper during transport, wherein a feeding direction of the recording paper is a first direction, A direction perpendicular to the first direction in a plane is defined as a second direction, and the paper guide is attached to an edge of the sheet cassette on the side where the recording paper is taken out with the sheet cassette attached. An adjacent inclined surface inclined at a predetermined angle in a paper feed direction with respect to a wall surface of the edge portion, wherein the inclined portion has a length in the second direction, the length of the recording paper being the second The predetermined angle is formed by applying an external force to the recording paper so that the recording paper comes into contact with the inclined portion, and the recording paper is formed into a loop shape by a reaction force received by the recording paper from the inclined portion. When buckling, the tip of the recording paper A sheet feeding device, wherein an end is set to an angle that buckles in a direction rising from the inclined portion. 5. The transport mechanism is provided so as to be able to contact and separate from the recording paper stacked and held in the paper feed cassette, and has a cylindrical portion having a substantially D-shaped cross section. A pickup roller comprising a pair of D-shaped roller portions fixedly disposed at predetermined intervals on the rotating shaft, the pickup roller being configured to have a planar shape portion; and a paper feed direction forward of the pickup roller. A feed roller and a first pinch roller that are disposed to face each other and pinch and cooperatively convey the recording paper; and are disposed to face forward of the feed roller and the first pinch roller in the paper feeding direction. 5. The paper feeding apparatus according to claim 4, further comprising a capstan roller and a second pinch roller for nipping and cooperatively transporting the recording paper. 6. The pickup roller further includes a roller having a circular cross section supported rotatably on a rotation shaft between the pair of D-shaped rollers, wherein a radius of the roller is 6. The sheet feeding device according to claim 5, wherein a size of the D-shaped roller portion is set to be smaller than a radius of the cylindrical portion, but larger than a dimension from a center of the D-shaped roller portion to the planar shape portion. 7. The capstan roller has a pair of projection regions formed at a predetermined interval on a cylindrical outer peripheral surface of a rotation shaft thereof and formed with a plurality of spike-shaped projections. The sheet feeder according to claim 5, wherein the second pinch roller has a pair of roller portions at a portion corresponding to the pair of protrusion regions of the capstan roller. 8. The sheet feeding device according to claim 7, wherein said pair of roller portions of said second pinch roller is made of resin or metal. 9. The width of each of the pair of roller portions of the second pinch roller is wider than the width of each of the pair of protrusion regions of the capstan roller.
The paper feeding device according to claim 7 or claim 8. 10. The sheet cassette according to claim 1, wherein the sheet cassette is engaged with the first edge of the bottom plate in the first direction, and the bottom plate is inclined. The paper feeder according to claim 4, further comprising a lever that pushes down the bottom raising plate so as to release the sheet.