JPH0867370A - Paper feed device - Google Patents

Abstract

PURPOSE: To surely feed a paper sheet one by one and improve operability and reliability regardless of the stiffness of the paper sheet by energizing a separation claw by means of a claw operation control spring, and automatically operating engagement and disengagement of the separation claw against the paper sheet according to the stiffness of the paper sheet. CONSTITUTION: In this paper feed device 12, the loading plate 17 of paper sheets 16 is vertically movably arranged on a tray main body 13. A separation claw 24 to be engaged with the extreme end angle part of the paper sheet 16 positioned on the uppermost part is arranged. In addition paper feed rollers 28 feeding the paper sheet 16 positioned on the uppermost part are arranged in the vicinity of the extreme end of the loading plate 17 over the tray main body 13. In this case, the separation claw 24 is energized by a claw operation control spring 26, and when the paper sheet 16 with low stiffness is fed, the engaged condition with the extreme end angle part of the paper sheet 16 positioned on the uppermost part is held. When the paper sheet 16 with high stiffness is fed, the claw is pushed by the extreme end angle part of the paper sheet 16, and moved so as to take refuge from the running route of the paper sheet 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device, and more particularly, it is possible to stack a plurality of sheets on top of each other and to feed the sheets one by one from above toward a printing position. Regarding a paper feeding device.

[0002]

2. Description of the Related Art Generally, in various printers such as a thermal transfer printer and a page printer, which are used as output devices for computers, word processors, facsimiles, etc., a plurality of sheets are stacked and placed on each other. A sheet feeding device called a cut sheet feeder is used to feed sheets one by one from the upper side toward a printing position.

An example of a conventional sheet feeding device used in such a printer will be described below with reference to FIG.

FIG. 5 shows a main part in a plain paper delivery state in which the topmost sheet of a plurality of weak sheets stacked on a sheet placement plate of a conventional sheet feeder can be delivered by a sheet feed roller. It is a top view shown.

As shown in FIG. 5, the conventional sheet feeding device 1 is
It has a tray body 2 and is formed in the inside of the tray body 2 in a substantially flat plate shape for stacking and placing sheets 3 selected from plain paper, OHP paper, cardboard, postcards and the like. A pair of left and right sheet placement plates 4 are provided. And
A support shaft 5 provided with a detent having a substantially D-shaped cross section for connecting the sheet placing plates 4 is attached to the lower surface side of the central portion of each sheet placing plate 4 in the vertical direction. By supporting both ends of the shaft 5 on both side surfaces of the tray main body 2 so as to be rotatable, the respective sheet placement plates 4 are arranged so as to be rotatable in the vertical direction about the support shaft 5. Further, each sheet placement plate 4 is movable in the left-right direction along the support shaft 5 according to the widthwise dimension of the sheet 3 by manual operation. Further, side guides 6 for positioning both widthwise end portions of the paper 3 are provided on the upper surface of each paper placement plate 4 so as to face the side surfaces of the tray body 2, respectively. 6 is independently movable with respect to the sheet placing plate 4 in the left-right direction.

On the lower surface side of each sheet placing plate 4, there is arranged a not-shown pressing spring which constantly urges each sheet placing plate 4 upward. Further, a paper support 7 is attached to a substantially central portion of the support shaft 5 in the length direction, and supports a substantially central portion in the width direction of the paper 3 located between the paper placing plates 4 from below. . The paper support 7 has a flat surface 7 a located in a virtual plane including the upper surface of each paper placement plate 4, and the flat surface 7 a contacts the paper 3.

At the corners located on the side of the tray main body 2 at the front end portions of the sheet placement plates 4, the sheets 3 placed at the top of the sheets 3 placed on the sheet placement plate 4 are placed. Separation claws 8 that are engaged with the corners of the tip are respectively provided.

Further, above the tray main body 2 and near the tip of the upper surface of the sheet placing plate 4 (more specifically, inside the sheet 3 in the width direction of the separating claws 8), the sheet placing plate 4 is placed. A paper feed roller 9 for contacting the uppermost paper 3 of the placed paper 3 and feeding the uppermost paper 3 is rotatably arranged. The paper feed roller 9 is The uppermost sheet 3 which is in contact with the sheet feeding roller 9 is rotationally driven by a driving force of a sheet feeding motor (not shown) so as to be sent out along a traveling path of the sheet 3 indicated by an arrow A in the figure. ing.

In such a conventional sheet feeding device 1,
A plurality of sheets of plain paper 3A, represented by plain paper, are stacked and placed on the upper surface of the sheet placing plate 4, and the sheet placing plate 4 and the side guides 6 are arranged along both widthwise end portions of the sheet 3A. The sheet 3A is held inside the tray main body 2 by moving and positioning the sheet 3A as described above and engaging the corners of the tip of the uppermost sheet 3 with the lower surface side of the separation claw 8.

Then, the uppermost sheet 3A stacked on the sheet stacking plate 4 is urged by the upward biasing force of the tray body 2.
Is pressed against the lower surface of the sheet feeding roller 9, and in this state, when the sheet feeding roller 9 is rotationally driven by the driving force of a sheet feeding motor (not shown), the frictional force between the sheet feeding roller 9 and the sheet 3 causes
A plurality of upper sheets 3A stacked on the sheet placing plate 4 are about to be conveyed, but only the uppermost sheet 3A of the sheets 3A to be conveyed is separated by the separating claw 8 by the separating claw 8. The sheet 3A is sent out from the tray main body 2 along the traveling path after passing over the sheet, and the sheet 3A sent out is fed toward the printing position inside the printer (not shown) so as to be fed.

That is, the plurality of weak sheets 3A stacked and placed on the upper surface of the sheet placing plate 4 are sequentially sent out one by one from the uppermost side by the separating claw 8.

In such a conventional sheet feeding device 1, as shown in FIG. 6, a tray main body 2 is provided by a supporting stay (not shown) provided inside a printer main body 11 of a desired printer 10 such as a thermal transfer printer. It is adapted to be attached to the printer body 11.

By the way, in the conventional paper feeding device 1,
There is no problem when using a weak paper 3A typified by plain paper, but a strong paper 3B typified by a postcard.
However, when the sheet 3B is used, the sheet 3B cannot pass over the separation claw 8, and the state in which the leading end of the sheet 3B is engaged by the separation claw 8 is maintained and the sheet 3B cannot be delivered. was there.

Therefore, in order to deal with such a problem, in the conventional paper feeding device 1, when the strong paper 3B represented by a postcard is used, as shown in FIG.
By manually moving each sheet placing plate 4 to the side surface side of the tray main body 2, the separating claws 8 arranged on the sheet placing plate 4 are positioned outside the both widthwise end portions of the sheet 3B. By retracting, the separating claws 8 are not used, and the sheets are sequentially delivered one by one from the uppermost side.

[0015]

However, in the above-described conventional paper feeding device 1, as shown in FIG. 6, the separating claw 8 is arranged inside the printer body 10 at a position where visibility is poor. When the user manually retracts both the paper placing plate 4 having the separation claw 8 and the side guide 6 corresponding to the strong paper 3B, the paper placing plate 4 and the side Both the guide 6 and the guide 6 must be operated, which requires a complicated operation, and it is troublesome to visually check whether or not the separation claw 8 has retracted from the corner of the leading end of the sheet 3B. was there.

In the conventional paper feeding device 1, even if the papers 3 have the same size, the strength (type) of the papers 3 is low.
Accordingly, both the sheet placing plate 4 on which the separation claw 8 is arranged and the side guide 6 have to be manually operated, which causes a problem that the operation is complicated.

Further, in the conventional paper feeding device 1, when the weak paper 3A is used as the paper 3, the separation pawl 8 is engaged with the paper 3A and the separation pawl 8 is retracted from the paper 3A. Since the sheet 3A can be delivered in any of the above states, the state in which the separating claw 8 is retracted from the sheet 3A unless the sheet feeding device 1 is driven after sufficiently checking the position of the separating claw 8 The paper is sent out by
There is a problem in that A causes an erroneous operation of overrunning.

Therefore, it is desired that the separating claw 8 can be easily engaged with and disengaged from the sheet 3 depending on the strength of the sheet 3.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a sheet feeding device capable of easily engaging and disengaging a separation claw from a sheet according to the strength of the sheet. To aim.

[0020]

In order to achieve the above-mentioned object, a sheet feeding device of the present invention according to claim 1 is a sheet stacking device for stacking and stacking a plurality of sheets on a tray body. The tray is arranged so as to be movable in the vertical direction, and a separation claw that is engaged with a corner of the leading edge of the paper placed on the top of the paper placed on the paper tray is provided. Above the main body, in the vicinity of the leading end of the sheet placement plate, a rotationally driven sheet feeding roller for delivering the sheet located at the uppermost position of the sheet placed on the sheet placement plate is disposed. In the paper feeding device, when the separation claw is used to feed a weak paper, the engagement state in which the leading edge of the uppermost paper is engaged is held, and the strong paper is fed. In this case, if the paper is pushed by the corners of the leading edge of the traveling paper, it may be It is characterized in that the movably formed so as to retreat into the travel path out of the paper.

Further, in the paper feeding device of the present invention as defined in claim 2, in claim 1, a claw support plate is movably disposed on the tray body, and the separation claw is formed on the claw support plate. Further, a claw operation control spring for operating the separation claw so as to urge the separation claw of the claw support plate in a direction to engage with the corner portion of the leading edge of the sheet is connected.

[0022]

According to the sheet feeding device of the present invention having the above-mentioned structure, the leading edge of the sheet located on the uppermost portion of the sheet placed on the sheet placing plate is engaged with the corner. The separating claw that automatically engages and disengages with the corner portion of the leading edge of the sheet located at the top according to the strength of the sheet.

Further, according to the sheet feeding device of the present invention, the separation claw engaged with the corner portion of the leading end of the sheet located on the uppermost portion of the sheet placed on the sheet placing plate. Is biased in a direction in which it is engaged with a corner portion of the leading end of the sheet by a claw operation control spring connected via a claw support plate. Then, when the separation claw is fed by the biasing force of the claw operation control spring, the separation claw holds the engaged state in which the leading edge corner of the sheet located at the uppermost position is engaged, and the waist claw of the waist is held. When sending strong paper, the paper is pushed by the corners of the leading edge of the traveling paper and moves so as to retract from the corners of the leading edge of the traveling paper. .

[0024]

The present invention will be described below with reference to the embodiments shown in the drawings.

FIG. 1 is a front view with a part omitted showing a main part of an embodiment of a sheet feeding device according to the present invention, and FIG. 2 is a side view with a part omitted showing the main part. 3 is a plan view showing a main part, and FIG. 4 is a perspective view of the vicinity of the separation claw viewed from the rear.

As shown in FIGS. 1 to 3, the sheet feeding device 12 of this embodiment has a tray main body 13 formed in a substantially flat plate shape, and both end portions of the tray main body 13 in the left-right direction. Support stays 14 that extend in the front-rear direction of the tray body 13 are provided upright in the vicinity. This support stay 1
A plurality of paper guides 15 formed like comb teeth are erected at the tip of the tray body 13 located between the four. Then, above the tray body 13 located between the support stays 14, a sheet placement plate formed in a substantially flat plate shape for loading sheets 16 selected from plain paper, OHP paper, cardboard, postcards and the like. 17 are provided.

The sheet placing plate 17 is urged upward by a pressing spring 18 provided on the lower surface side near the leading end of the sheet placing plate 17, and is supported at its base end. By supporting the pin 19 rotatably on the side surface of the support stay 14, the pin 19 is rotatably arranged in the up-down direction about the support pin 19. A plurality of recesses 2 that are loosely fitted in the paper guide 15 are provided at the leading end of the paper placing plate 17.
0 is formed. Further, a cutout portion 21 having a substantially rectangular plane is formed at the right corner of the front end portion of the sheet placing plate 17. Further, depending on the size of the paper 16, the left-right direction (width direction of the paper 16) is provided on the upper part on the left end side of the paper placing plate 17.
A side guide 22 that is freely movable is provided. The side guide 22 is manually moved in the left-right direction according to the size of the sheet 16 in the width direction, and restrains the position of the side end portion of the sheet 16 placed on the upper surface of the sheet placing plate 17. I am supposed to get it.

In the vicinity of the right front end of the upper surface of the tray main body 13, there is provided a substantially flat plate-like claw support plate 23 formed in a substantially rectangular front shape and extending substantially parallel to the front end of the tray main body 13. The claw support plate 23 is arranged so as to be rotatable in the left-right direction when viewed from above with a substantially central portion as a center. When stacked, the separation claw 2 that engages with the right corner of the leading end of the sheets 16 at least at the top of the stacked sheets 16
4 are provided.

As shown in detail in FIG. 4, the upper and lower ends of the pawl support plate 23 at the substantially central portion in the lengthwise direction are located outside the support stay 14a formed on the right end side of the tray body 13. A mounting portion 23a pivotally attached to a vertically mounted rotation support shaft 25
The claw support plate 23 is rotatable about the rotation support shaft 25. The respective mounting portions 23a face each other so as to extend in parallel from the upper end portion and the lower end portion of a substantially central portion of the claw support plate 23 in the lengthwise direction at intervals in the vertical direction. Then, when a plurality of sheets 16 are stacked on the sheet placing plate 17 on the upper end portion of the left end portion of the claw support plate 23, the leading end portion of the sheets 16 positioned at least at the top of the stacked sheets 16 are stacked. A separation claw 24 that engages with the right corner is formed. Further, a through hole 23b penetrating in the plate thickness direction is formed at a substantially central portion in the vertical direction of the right end portion of the claw support plate 23.
One end of a claw movement control spring 26 having a spring load of about 30 g for controlling the operation state of the separation claw 24 that interlocks with the claw support plate 23 is locked to 3b. Further, the other end of the pawl movement control spring 26 is locked by a locking pin 27 provided upright in the vicinity of the front right corner of the top surface of the tray body 13.
As shown by the solid line in FIG. 3, the pawl operation control spring 26 can always maintain the state in which the separation pawl 24 is biased in the direction of engaging the corner portion of the leading end portion of the sheet 16. There is. .

The urging force of the pawl movement control spring 26 in this embodiment will be described in more detail. The urging force (spring load) of the pawl movement control spring 26 in this embodiment is the sheet placing plate 1.
When a plurality of weak papers 16 are placed on the upper surface of the sheet 7 and the weak papers 16 are sent out, the separation claws 24 are set to the weak paper 16 as shown by the solid lines in FIG. The engagement state in which the uppermost sheet 16 is engaged with the corner portion of the leading end portion can be maintained against the force applied to the corner portion of the leading end portion.

Further, the biasing force of the pawl movement control spring 26 of the present embodiment is such that a plurality of stiff sheets 16 are placed on the sheet placing plate 17.
When the paper 16 having a high rigidity is placed and fed out, the separating claw 24 is pushed by the corner portion of the leading end of the paper 16 having a strong running to separate the paper 16 as shown by the broken line in FIG. Nail 2
4 moves in the advancing direction which is the paper feeding direction of the paper 16 about the rotary support shaft 25 (rotates counterclockwise when viewed from above)
As a result, the separation claw 24 retracts from the corner of the leading edge of the sheet 16 to the outside of the traveling path of the sheet 16, and the engagement state between the separation claw 24 and the leading edge of the stiff sheet 16 is released. It is like this.

The urging force (spring load) of the pawl operation control spring 26 is determined by the output of the paper 16, the strength of the paper 16 (rigidity), the separation pawl 24 to the rotary support shaft 25 of the pawl support plate 23. The distance from the axis of the rotation support shaft 25 of the claw support plate 23 to the mounting portion of the claw operation control spring 26 of the claw support plate 23, the mounting space, and the like. It is not limited to the biasing force of the embodiment.

The shape of the claw support plate 23 and the mounting position of the separation claw on the claw support plate 23 may be determined according to the design concept, and is not particularly limited to the shape and configuration of this embodiment.

Returning to FIG. 1 to FIG. 3, the tray body 1 is
In the vicinity of the front end of the sheet placing plate 17 above the sheet 3, the sheet 16 located at the uppermost position of the plurality of sheets 16 placed on the sheet placing plate 17 is abutted, and the uppermost sheet 16 is contacted. A plurality of paper feed rollers 28 for sending 16 to a print position (not shown) are rotatably arranged. Each of the paper feed rollers 28 is the uppermost paper sheet that is in contact with the paper feed roller 28. 16 is sent out along the traveling route indicated by the arrow B, and is rotationally driven by the driving force of a sheet feeding motor (not shown). The paper feed rollers 28 are
The support stay 14 is fixed to a rotary shaft 29 pivotally attached to the support stay 14 so as to penetrate the support stay 14 toward the outside, and a paper feed gear 30 is attached to the left end of the rotary shaft 29. The paper feed roller 28 is rotatably driven by the drive force of a paper feed motor (not shown) transmitted to the paper feed gear 30.

Next, the operation of this embodiment having the above-mentioned structure will be described.

In the sheet feeding device 12 of this embodiment, as shown in FIG.
As shown in FIG.
6 can be placed, and the widthwise both ends of the plurality of sheets 16 stacked on the upper surface of the sheet placing plate 17 are the inner surface of the right support stay 14a of the tray body 13 and the width of the sheet 16. It is positioned by the inner surface of the side guide 22 which is movable in the direction. The separation claw 24 is engaged with the right corner of the leading end of the paper 16 located at the top of the plurality of papers 16 placed on the upper surface of the paper placement plate 17. Further, the uppermost sheet 16 stacked on the sheet mounting plate 17 is pressed against the lower surface of the sheet feeding roller 28 by the upward biasing force of the tray body 13 by the pressing spring 18.

Then, when the feeding operation of the sheet 16 by the sheet feeding device 12 of the present embodiment is started, a sheet feeding motor (not shown) is driven based on the control command, and the upward biasing force of the tray body 13 is applied. The paper feed roller 28, which is in contact with the uppermost sheet 16 stacked on the sheet mounting plate 17, is rotationally driven in the clockwise direction, and a plurality of sheets mounted on the upper surface of the sheet mounting plate 17. Paper 16 located at the top of 16
Is sent out along the traveling path of the sheet 16 indicated by the arrow B in FIG.

When the paper 16 is sent out, if the paper 16 is a weak paper 16 represented by plain paper, the paper 16 having a low elasticity has a small rigidity, and therefore the separation pawl is interposed via the pawl support plate 23. Claw motion control spring 26 controlling the motion of 24
The urging force of the sheet 16 against the force that the uppermost sheet 16 stacked on the sheet placing plate 17 pushes the separating claw 24 in the sheet feeding direction of the sheet 16, and 3 is deformed, and as a result, as shown by the solid line in FIG. 3, the separation claw 24 holds the engagement state in which the separation claw 24 is engaged with the right corner of the leading end of the paper 16 located at the top. . As a result, the uppermost sheet 16 stacked on the sheet stacking plate 17
Only the sheets of paper 16 over the separating claw 24 and the weak paper 16 stacked on the sheet placing plate 17 are separated.
With the separating function of 1, the sheets are sequentially sent out one by one from the uppermost side along the traveling path of the sheet 16 shown by the arrow B in FIG.

When the paper 16 is sent out, if the paper 16 is a strong paper 16 such as a postcard, the rigidity of the strong paper 16 is large, so that the separation pawl is interposed via the pawl support plate 23. Claw motion control spring 26 controlling the position of 24
The urging force of 2 cannot withstand the force that the uppermost sheet 16 stacked on the sheet mounting plate 17 pushes the separation claw 24 in the sheet feeding direction of the sheet 16, and as a result, as shown in FIG. As indicated by the broken line, the separation claw 24 is pushed (moved) in the advancing direction of the sheet 16 by being pushed by the corner portion of the front end of the stiff sheet 16 to extend the claw movement control spring 26, The separation claw 24 retreats from the corner of the leading edge of the sheet 16 to the outside of the traveling path of the sheet 16. As a result, the stiff sheets 16 stacked on the sheet stacking plate 17 are sequentially one by one from the uppermost side without using the separating function of the separating claw 24, and are indicated by the arrow B in FIG. The sheet 16 is sent out along the traveling route.

Therefore, in this embodiment, the paper 1
Depending on the strength (kind) of the waist of 6, the separation claw 24 is located above the top right corner of the paper 16 located at the top of the plurality of papers 16 placed on the upper surface of the paper placement plate 17. You can easily engage and disengage by turning to the left and right when viewed from the
As a result, the separation claw 24 is positioned on the uppermost part of the sheet 16 and the separation claw 24 is positioned on the uppermost part of the sheet 16 depending on the rigidity of the sheet 16, and the separation claw 24 is positioned on the uppermost part of the sheet 16. It is possible to automatically and selectively take either one of the separated claw retracted state with respect to the sheet 16 to be used, and reliably both the sheet 16 with weak stiffness and the sheet 16 with strong stiffness. Can be sent out.

That is, in this embodiment, the paper 16
It is possible to automatically engage and disengage the separation claw 24 with respect to the paper 16 in accordance with the strength (type) of the waist of the paper. It is possible to reliably send the sheets one by one, and it is possible to surely prevent the malfunction of the weakly stiff paper 16 running over.

Further, in the present embodiment, the engaging / disengaging operation of the separation claw 24 with respect to the paper 16 can be automatically performed according to the strength (type) of the waist of the paper 16.
It is not necessary to move the separation claw 24 according to the strength (type) of the waist of the user or to determine the engagement / disengagement operation of the separation claw 24 with respect to the sheet 16, and thus the operability and reliability can be reliably improved. .

The present invention is not limited to the above embodiment, but can be modified as necessary.

[0044]

As described above, according to the paper feeding apparatus of the present invention, it is possible to automatically engage and disengage the separating claw with respect to the sheet in accordance with the strength of the sheet.
This has an extremely excellent effect that the sheets can be surely delivered one by one regardless of the strength of the sheets and the operability and reliability can be surely improved.

[Brief description of drawings]

FIG. 1 is a front view with a part omitted showing a main part of an embodiment of a paper feeding device according to the present invention.

FIG. 2 is a side view with a part omitted showing a main part of an embodiment of a sheet feeding device according to the present invention.

FIG. 3 is a plan view showing a main part of an embodiment of a paper feeding device according to the present invention.

FIG. 4 is a perspective view of the vicinity of a separating claw of an embodiment of a sheet feeding device according to the present invention as seen from the rear side.

FIG. 5 is a plain paper delivery state in which a paper located at the top of weak papers represented by a plurality of plain papers stacked on a paper placement plate of a conventional paper feeder can be delivered by a paper feed roller. Front view showing essential parts

FIG. 6 is a schematic diagram showing a printer using a conventional paper feeding device.

FIG. 7 is a diagram showing a cardboard delivery state in which a sheet located at the top of a strong sheet represented by a plurality of postcards stacked on a sheet placement plate of a conventional sheet feeder can be delivered by a sheet feeding roller. Figure similar to 5

[Explanation of symbols]

 12 Paper Feeding Device 13 Tray Main Body 16 Paper 17 Paper Loading Plate 22 Side Guide 23 Claw Support Plate 24 Separation Claw 25 Rotating Spindle 26 Claw Motion Control Spring 27 Locking Pin 28 Feeding Roller

Claims (2)

[Claims] 1. A tray main body is provided with a paper placing plate for stacking and placing a plurality of sheets of paper so as to be vertically movable, and the paper placed on the paper placing plate is A separation claw that engages with a corner of the leading end of the sheet located at the top is provided, and is placed on the sheet loading plate above the tray body and near the leading edge of the sheet loading plate. In a sheet feeding device provided with a rotation driven sheet feeding roller for feeding the sheet located at the uppermost position of the sheet, the separating claw is positioned at the uppermost position when feeding a weak sheet. In the case of holding the engaged state in which the leading edge of the sheet to be held is held and sending the stiff sheet, the sheet is pushed by the leading edge of the running sheet to move the running sheet. A sheet feeding device characterized in that it is formed so as to be retracted from a corner portion of a strong sheet to the outside of a sheet traveling path. 2. A claw support plate is movably disposed on the tray body, the separation claw is formed on the claw support plate, and the separation claw of the claw support plate is engaged with a corner portion of the leading edge of the sheet. 2. The paper feeding device according to claim 1, further comprising a pawl operation control spring connected to operate the separation pawl so as to urge the separating pawl in a direction.