Patent Application
20170120636
Field of the Invention
The present invention relates to a sheet supplying apparatus that draws a sheet out of a sheet roll, in which a sheet is wound in a rolled manner, so as to supply the sheet, and a printing apparatus.
Description of the Related Art
It has been known a printing apparatus provided with a sheet supplying apparatus that draws a sheet out of a sheet roll so as to supply the sheet, wherein the printing apparatus prints an image on a sheet supplied from the sheet supplying apparatus. A sheet supplying apparatus provided for a printing apparatus disclosed in Japanese Patent Laid-Open No. H11-11750 (1999) is configured to convey a sheet drawn out of a sheet roll upward through a conveyance path that is formed between a movable type separating flapper and a conveyance guide and extends from under to above. The movable type separating flapper is pressed at the lower end thereof against the outer periphery of the sheet roll, thereby separating the tip of the sheet from the sheet roll.
In the sheet supplying apparatus disclosed in Japanese Patent Laid-Open No. H11-11750 (1999), the separating flapper moves as the outer diameter of the sheet roll becomes smaller so that the conveyance path formed between the separating flapper and the conveyance guide enlarges. The sheet drawn out of the sheet roll is conveyed upward against the weight of the sheet through the conveyance path that enlarges in the above-described manner, and therefore, buckling possibly occurs. In addition, since a sheet drawn out of a sheet roll having a small outer diameter is strongly curled, the sheet is hardly conveyed through the conveyance path in a smooth manner.
The present invention provides a sheet supplying apparatus that can securely draw a sheet out of a sheet roll irrespective of the size of the outer diameter of the sheet roll so as to convey the sheet, and a printing apparatus.
In one aspect of the present invention there is provided an inkjet printing apparatus having a printing unit configured to perform inkjet printing on a sheet that is continuous, a basket unit configured to receive a sheet on which an image is printed by the printing unit, a first driving unit configured to apply a rotational force to a first spool that holds a roll of the sheet, a first pressing roller configured to press an outer peripheral surface of the roll held by the first spool, wherein the first pressing roller is movable according to reducing of an outer diameter of the roll, a first guide configured to move in association with the movement of the first pressing roller so as to guide the sheet drawn from the roll toward the printing unit, a second driving unit configured to apply a rotational force to a second spool that holds a roll of the sheet, a second pressing roller configured to press an outer peripheral surface of the roll held by the second spool, wherein the second pressing roller is movable according to reducing of an outer diameter of the roll held by the second spool, and a second guide configured to move in association with the movement of the second pressing roller so as to guide the sheet drawn from the roll toward the printing unit. The printing apparatus is configured to perform (a) a first mode in which the second driving unit drives the second spool to feed out the sheet from the roll to the printing unit via the second guide, the printing unit performs printing on the fed sheet, and the basket unit receives the printed sheet printed by the printing unit, and (b) a second mode in which the first driving unit drives the first spool to feed out the sheet from the roll to the printing unit via the first guide, the printing unit performs printing on the fed sheet, and the second driving unit drives the second spool to wind up the printed sheet printed by the printing unit as a roll.
In the another aspect of the present invention, there is provided a sheet supplying apparatus that draws a sheet out of a sheet roll and supplies the sheet, the sheet supplying apparatus comprising:
a pressing unit having a roller configured to move according to an outer diameter of the sheet roll, to be brought into press-contact with an outer periphery of the sheet roll from below, with respect to the direction of gravity; and
a lower guide member configured to move in association with the pressing unit so as to guide a lower surface of the sheet that is drawn through the pressing unit.
In the yet another aspect of the present invention, there is provided a sheet winding apparatus that winds a sheet in a form of a sheet roll, the sheet winding apparatus comprising:
a pressing unit having a roller configured to move according to an outer diameter of the sheet roll, to be brought into press-contact with an outer periphery of the sheet roll from below, with respect to the direction of gravity;
a lower guide member configured to move in association with the pressing unit so as to guide a lower surface of the sheet that is drawn through the pressing unit; and
a winding/driving mechanism configured to rotate the sheet roll in a winding direction of the sheet.
In the third aspect of the present invention, there is provided a printing apparatus comprising:
a sheet supplying apparatus that draws a sheet out of a sheet roll and supplies the sheet, the sheet supplying apparatus comprising a pressing unit having a roller configured to move according to an outer diameter of the sheet roll, to be brought into press-contact with an outer periphery of the sheet roll from under in a gravity direction, and a lower guide member configured to move in association with the pressing unit so as to guide a lower surface of the sheet that is drawn through the pressing unit; and
a print unit configured to print an image on the sheet to be supplied from the sheet supplying apparatus.
In the still yet another aspect of the present invention, there is provided a printing apparatus comprising:
a sheet winding apparatus that winds a sheet in a form of a sheet roll, the sheet winding apparatus comprising a pressing unit having a roller configured to move according to an outer diameter of the sheet roll, to be brought into press-contact with an outer periphery of the sheet roll from below, with respect to the direction of gravity, a lower guide member configured to move in association with the pressing unit so as to guide a lower surface of the sheet that is drawn through the pressing unit, and a winding/driving mechanism configured to rotate the sheet roll in a winding direction of the sheet; and
a print unit configured to print an image on the sheet to be wound by the sheet winding apparatus.
According to the present invention, the pressing unit is brought into press-contact with the outer periphery of the sheet roll from under, and furthermore, the lower side of the sheet drawn through the pressing unit is guided by the lower guide member, so that the sheet can be smoothly guided and supplied. Moreover, the pressing unit and the lower guide member move according to the outer diameter of the sheet roll, and therefore, the sheet can be securely drawn out of the sheet roll irrespective of the size of the outer diameter of the sheet roll, and then, conveyed.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
Embodiments of the present invention will be described below with reference to the attached drawings.
As shown in
A spool member 2 formed into a shaft-like shape is inserted into a hollow hole of the sheet roll R, and then, the spool member 2 is driven forward or reversely by a roll driving motor, described later. In this manner, the sheet roll R is held at the center thereof, to be thus rotated forward and reversely in directions indicated by arrows C1 and C2. The supplying apparatus 200 is provided with a drive unit 3, an arm member (i.e., a moving member) 4, an arm turning shaft 5, a first sheet sensor 6, an oscillating member 7, driven rollers 8 and 9 (i.e., pressing units), a separating flapper (i.e., an upper guide member) 10, and a flapper swing shaft 11, as described later.
A conveyance guide 12 guides the obverse and reverse of the sheet 1 drawn out of the supplying apparatus 200 while guiding the sheet 1 to the print unit 400. A conveyance roller 14 is rotated forward and reversely in directions indicated by arrows D1 and D2 by a conveyance roller driving motor, described later. A nip roller 15 can be rotated following the rotation of the conveyance roller 14, and furthermore, can be brought into or out of contact with the conveyance roller 14 by a nip roller separating motor, not shown. Moreover, the nip roller 15 can adjust nipping force. The conveyance roller 14 is rotated upon detection of the tip of the sheet 1 by a second sheet sensor 16. A conveyance speed of the sheet 1 by the conveyance roller 14 is set to be higher than the drawing speed of the sheet 1 according to the rotation of the sheet roll R, and thus, back tension can be applied to the sheet 1 that can be conveyed in the tensile state. Consequently, it is possible to prevent the sheet 1 from sagging, so as to suppress the generation of folds on the sheet 1 or a conveyance error.
A platen 17 at the print unit 400 adsorbs the reverse of the sheet 1 through suction holes 17a under vacuum generated by a suction fan 19. In this manner, the position of the sheet 1 is restricted along the platen 17, so that the print head 18 can print an image with high accuracy. A cutter 20 can cut the sheet 1 having the image printed thereon. A cover 42 for the sheet roll R prevents the sheet 1 having the image printed thereon from returning to the supplying apparatus 200. The operation of the printing apparatus 100 is controlled by a CPU, described later.
In setting the spool member 2 at the sheet roll R, first, the spool flange 24 on the non-reference side fitted to the spool shaft 21 is detached, and then, the spool shaft 21 is inserted into the hollow hole of the sheet roll R. Since the outer diameter of the spool shaft 21 is smaller than the inner diameter of the hollow hole of the sheet roll R, a clearance is defined therebetween. Therefore, a user can insert the spool shaft 21 into the hollow hole by a slight force. At the time when the right end of the sheet roll R in
In this manner, the sheet roll R is fitted to the spool member 2, as shown in
The spool holders 31 are disposed at positions corresponding to both ends of the spool shaft 21. The inner surface of each of the spool holders 31 is formed into a U shape. The end of the spool shaft 21 can be inserted through an opening formed at the spool holder 31. In a state in which the spool member 2 is inserted into the spool holders 31, the spool gear 25 is connected to a roll driving motor, described later, via a drive gear 30 on the side of the supplying apparatus 200. The roll driving motor drives the sheet roll R together with the spool member 2 forward and reversely, thereby supplying and winding the sheet 1. A roll sensor 32 is adapted to detect the sheet roll R.
The arm member (i.e., the moving member) 4 is attached to the conveyance guide 12 via the turning shaft 5 in a manner turnable in directions indicated by arrows A1 and A2. At the upper portion of the arm member 4 is formed a guide 4b (i.e., a lower side guide member) for guiding the lower surface of the sheet 1 drawn out of the sheet roll R. A torsion coil spring 3c for pressing the arm member 4 in the direction indicated by the arrow A1 is interposed between the arm member 4 and a rotary cam 3a of the drive unit 3. The rotary cam 3a is rotated by a pressurizing/driving motor 34, described later, thereby varying force of the torsion coil spring 3c for pressing the arm member 4 in the direction indicated by the arrow A1. In a case where a relatively large diameter portion 3a-1 of the rotary cam 3a is brought into contact with the torsion coil spring 3c, the pressing force becomes large to generate “pressing force for strong nip,” described later. In contrast, in a case where a relatively small diameter portion 3a-2 of the rotary cam 3a is brought into contact with the torsion coil spring 3c, the pressing force becomes small to generate “pressing force for weak nip,” described later. Furthermore, in a case where a flat portion 3a-3 of the rotary cam 3a is brought into contact with the torsion coil spring 3c, the pressing force for pressing the arm member 4 in the direction indicated by the arrow A1 is released, so that first and second driven rollers (rotators), described later, are separated from the sheet roll R.
The supplying apparatus 200 is configured in such a manner as to be freely switched among three stages: the state in which the arm member 4 is pressed by a predetermined “pressing force for weak nip”; the state in which the arm member 4 is pressed by a predetermined “pressing force for strong nip”; and the state in which the pressing force for the arm member 4 is released.
The oscillating member 7 is oscillatably attached to the arm member 4. First and second driven rollers (i.e., pressing unit) 8 and 9 shifted in the circumferential direction of the sheet roll R are rotatably attached to the oscillating member 7. The first and second driven rollers 8 and 9 are brought into press-contact with the outer periphery of the sheet roll R from below, with respect to the direction of gravity, by the pressing force against the arm member 4 in the direction indicated by the arrow A1. In other words, the first and second driven rollers 8 and 9 are brought into press-contact with the outer periphery of the sheet roll R from below the center axis in the horizontal direction of the sheet roll R with respect to the direction of gravity. The press-contact force is varied according to the pressing force for pressing the arm member 4 in the direction indicated by the arrow A1. As a consequence, the drive unit 3 functions as a pressing mechanism for pressing the arm member 4. The drive unit 3 also functions as a moving mechanism for moving the arm member 4 in such a manner as to separate the first and second driven rollers 8 and 9 from the outer periphery of the sheet roll R.
As shown in
The shaft receiver 7a is disposed at a position below, with respect to the direction of gravity, the oscillating member 7, and thus, is supported by the rotary shaft 4a in such a manner that the oscillating member 7 takes a stable posture in each of X-, Y-, and Z-axial directions. Specifically, like the left oscillating member 7 in
The rotary shaft 4a has a circular cross section and extends in the X-axial direction. The shaft receiver 7a has a groove having U-shaped cross section and extends in the X-axial direction. The upper portion of the former rotary shaft 4a is stably fitted to the groove in the latter, so that the oscillating member 7 takes a stable posture, like the left oscillating member 7 shown in
Although the equalizing mechanism is disposed at a connecting portion between the oscillating member 7 and the arm member 4 in the present embodiment, an equalizing mechanism may be disposed at a connecting portion between the arm member 4 and the conveyance guide 12. Moreover, the plurality of oscillating members 7 are arranged at intervals in the widthwise direction of the sheet 1 in the present embodiment. In a case where the position of the spool flange 24 on the non-reference side with reference to the spool flange 23 on the reference side is varied according to the width of the sheet 1, the spool flange 24 on the non-reference side may be located between the adjacent oscillating members 7. In this manner, it is possible to avoid any interference between the oscillating member 7 and the spool flange 24 on the non-reference side.
To the main body of the printing apparatus 100 (i.e., a printer body) is swingably attached with the separating flapper 10 positioned upward of the arm member 4 on the swing shaft 11 in directions indicated by arrows B1 and B2. The separating flapper 10 is configured such that the sheet roll R is slightly pressed by its own weight. In a case where the sheet roll R need be more strongly pressed, an urging force by an urging member such as a spring may be used. A driven roller 10a is rotatably provided at a contact portion between the separating flapper 10 and the sheet roll R so as to suppress an influence on the sheet 1 by the pressing force. Moreover, a separator 10b at the tip of the separating flapper 10 is formed in such a manner as to extend up to a position as close to the surface of the sheet roll R as possible in order to facilitate the separation of the tip of the sheet from the sheet roll R.
The sheet 1 is drawn out of the sheet roll R through above the driven rollers 8 and 9, the lower surface of the sheet 1 is guided by the guide 4b at the upper portion of the arm member 4, and then, the sheet 1 is supplied through a supply path formed between the separating flapper 10 and the arm member 4. In this manner, the driven rollers 8 and 9 are brought into press-contact with the outer periphery of the sheet roll R from under, and then, the lower surface of the sheet 1 drawn through above the driven rollers 8 and 9 is guided by the guide 4b. Consequently, the sheet 1 can be smoothly supplied by utilizing its own weight. Additionally, the driven rollers 8 and 9 and the guide 4b are moved according to the outer diameter of the sheet roll R, so that the sheet 1 can be securely drawn out of the sheet roll R to be conveyed irrespectively of the size of the outer diameter of the sheet roll R.
The sheet 1 drawn out of the sheet roll R passes under a lower surface 10c of the separating flapper 10, and then, passes under a lower surface 12a of the conveyance guide 12. The lower surface 12a of the conveyance guide 12 is formed into a shape in conformity with a virtual circle on the swing shaft 11, so that a supply path without any step between the lower surface 10c and the lower surface 12a can be formed irrespective of the swing position of the separating flapper 10 in the directions indicated by the arrows B1 and B2. In this manner, the tip of the sheet 1 cannot be stuck on the supply path. The lower surface 10c of the separating flapper 10 is formed into a curved shape in conformity with the virtual circle on the swing shaft 11.
It is desirable that the first sheet sensor 6 provided on the arm member 4 should be located at a position slightly shifted downstream in the conveyance direction of the sheet 1 from the nip position between the sheet roll R and the driven roller 8. In the present embodiment, the two supplying apparatuses 200 are provided in a vertical direction. Therefore, the state in which the sheet 1 is supplied from one of the supplying apparatuses 200 can be switched to the state in which the sheet 1 is supplied from the other supplying apparatus 200. In this case, one of the supplying apparatuses 200 rewinds the sheet 1, which has been supplied so far, around the sheet roll R, and then, retracts the tip of the sheet 1 up to a position at which the sheet sensor 6 detects the tip of the sheet 1. In a case where the sheet sensor 6 is largely shifted downstream in the conveyance direction more than the present embodiment, the tip of the sheet 1 suspends into a clearance defined between the driven roller 8 and the arm member 4 by its own weight, thereby inducing an inconvenience of an adverse influence on the nip state of the sheet 1. Like the present embodiment, the sheet sensor 6 is disposed near the nip position between the sheet roll R and the driven roller 8, thus suppressing the generation of suspension by its own weight, so as to hardly mark a nip scar on the sheet 1.
Since the arm member 4 is pressed all the time in the direction indicated by the arrow A1 by the torsion coil spring 3c, the arm member 4 is turned in the direction indicated by the arrow A1 according to a decrease in outer diameter of the sheet roll R. Since the separating flapper 10 also is pressed all the time in the direction indicated by the arrow B1, the separating flapper 10 is swung in the direction indicated by the arrow B1 according to a decrease in outer diameter of the sheet roll R. Consequently, the separating flapper 10 forms the supply path between the conveyance guide 12 and the same even in a case where the outer diameter of the sheet roll R is decreased, thus guiding the upper surface of the sheet 1 by the lower surface 10c. In this manner, the arm member 4 is turned and the separating flapper 10 is swung according to a change in outer diameter of the sheet roll R, so that a substantially constant supply path is formed between the arm member 4 and the separating flapper 10 irrespective of the size of the outer diameter of the roll. As a consequence, even a sheet 1 having a low rigidity can be securely supplied without any buckling.
First of all, the cover (i.e., a dust roll cover) 42 (see
A user sets the sheet roll R in this manner, and then, manually rotates the sheet roll R in the direction indicated by the arrow C2 to eliminate the sag of the sheet 1. Thereafter, the user manually rotates at least either one of the spool flanges 23 and 24 in the direction indicated by the arrow C1. In this manner, the tip of the sheet 1 is inserted into a sheet supply port defined between the arm member 4 and the separating flapper 10 (step S3). Upon the detection of the tip of the sheet 1 by the first sheet sensor 6, a CPU, described later, in the printing apparatus 100 displays a message of “close dust roll cover” on a display of the operation panel 28 (see
After that, the CPU rotates the sheet roll R in the direction indicated by the arrow C1 by the roll driving motor, described later, thereby starting the supply of the sheet 1 (step S9). Upon the detection of the tip of the sheet 1 by the second sheet sensor 16 (step S10), the CPU rotates the conveyance roller 14 forward in the direction indicated by the arrow D1, thereby picking up the tip of the sheet 1 (step S11). Upon completion of the picking-up, the CPU releases the pressing force for pressing the arm member 4 at the supplying apparatus 200 in the direction indicated by the arrow A1, thus separating the first and second driven rollers 8 and 9 from the sheet roll R (a nip releasing state) (step S12).
Thereafter, the CPU detects the skewing of the sheet 1 conveyed inside of the sheet conveying apparatus 300. Specifically, the sheet 1 is conveyed inside of the sheet conveying apparatus 300 by a predetermined amount, and a sensor or the like provided for the sheet conveying apparatus 300 detects the skewing amount generated at this time. In a case where the skewing amount is larger than an allowable amount, the sheet 1 is repeatedly fed forward and backward according to the forward and reverse rotation of the conveyance roller 14 and sheet roll R. This operation corrects the skewing of the sheet 1 (step S13). In this manner, in correcting the skewing of the sheet 1 and printing an image on the sheet 1, the supplying apparatus 200 is released from the nip, thereby avoiding any adverse influence on the correction accuracy of the skewing of the sheet 1 and the print accuracy of an image by the driven rollers 8 and 9. And then, the CPU moves the tip of the sheet 1 up to a standby position (i.e., a predetermined position) at the print unit 400 inside by the sheet conveying unit 300 (step S14) before the start of a printing operation. In this manner, the supply preparation of the sheet 1 is completed. Thereafter, the sheet 1 is drawn out of the sheet roll R according to the rotation of the sheet roll R, to be thus conveyed to the print unit 400 by the sheet conveying unit 300.
In a case where the sheet roll R set at the supply apparatus 200 is detected by the roll sensor 32, after the tip of the sheet 1 is detected by the first sheet sensor 6, the CPU 201 receives set completion information. Consequently, the CPU 201 issues a rotation command for the pressurizing/driving motor 34, to thus rotate it, thereby adjusting the pressing force against the arm member 4. Thereafter, the CPU 201 allows the roll driving motor 33 to rotate the sheet roll R forward in the direction indicated by the arrow C1, thus feeding the sheet 1. After that, the CPU 201 allows the conveyance roller driving motor 35 to rotate the conveyance roller 14 forward in the direction indicated by the arrow D1 in a case where the second sheet sensor 16 detects the tip of the sheet 1, thus conveying the sheet 1.
In the first embodiment, the supplying apparatus 200 is brought into the nip releasing state during the correction of skewing of the sheet 1 and the printing operation of an image on the sheet 1. In the present embodiment, a supplying apparatus 200 is brought into the nip releasing state also in a case where the sheet 1 cannot be automatically supplied. For example, in a case where the sheet 1 is of a type having a high conveyance resistance caused by strong curl due to a high rigidity, it is difficult to automatically supply the sheet 1, unlike the first embodiment.
In the present embodiment, first, as shown in
The first embodiment is configured such that the pressing force of the arm member 4 can be switched on three stages: the strong nip state, the weak nip state, and the releasing state in the supplying apparatus 200. The adjustment stages of the pressing force are not limited to three, and further, the pressing force may be adjusted on a continuously variable stage. In this case, the pressing force in the strong nip state is optimally set according to a conveyance resistance that depends upon the shape of a conveyance path of the sheet 1, the rigidity of the sheet 1, and the friction coefficient of the surface of the sheet 1. In setting the sheet roll R, the supplying apparatus 200 is brought into the weak nip state, as described above, and the lock mechanism for locking the spool shaft 21 in such a manner as not to float from the spool holder 31 is brought into an unlocked state. Therefore, the pressing force in the weak nip state is optimally set in such a manner as not to allow the spool shaft 21 to float even in the state in which only the paper core of the sheet roll R is set to the spool shaft 21.
For example, in the case of sheets that are capable of pressed by a high pressing force while being supplied, such as a high rigid sheet like a coated paper and a sheet having a high weighing capacity typified by canvas, the pressing force in the strong nip state is highly set. In this manner, the sheet is strongly conveyed, and thus, the sheet can be securely supplied. Specifically, the pressing force in the strong nip state is more highly set with respect to the sheet 1 that is hardly supplied, so that more types of sheets 1 can be automatically supplied. Alternatively, the sheet 1 that is hardly automatically supplied can be manually supplied, like in the second embodiment.
A supplying apparatus 200 in the present embodiment is not provided with the rotary cam 3a at the drive unit 3 in the above-described embodiments, as shown in
The type of sheet to be used may be limited according to a model of printing apparatus. Plain paper is mainly used in a CAD machine, for example. Since the plain paper has a low rigidity, its conveyance resistance is not so high. Therefore, even in the case of a configuration in which the pressing force of the arm member 4 is constant and a nip pressure cannot be changed, the plain paper can be supplied. In this manner, according to the type of sheet to be used in the printing apparatus, the configuration for changing the pressing force of the arm member 4 is omitted, thus simplifying the configuration of the supplying apparatus 200 and the printing apparatus 100 so as to reduce costs.
A support arm 41a is supported on a rotary shaft 41 at a constant position in the supplying apparatus 200 in a manner turnable in directions indicated by arrows E1 and E2. A separating flapper 40 is supported on a flapper shaft 40b disposed at the support arm 41a in a manner swingable in directions indicated by arrows F1 and F2. The separating flapper 40 is pressed on the guide 4b of the arm member 4 in a movable manner by its own weight or a spring having a low load, not shown, via a slide member (i.e., a rotatable roller) 40a. The separating flapper 40 is provided with a restricting member 40d that is slidable in directions indicated by arrows G1 and G2 along a slot 12b formed at the conveyance guide 12. The restricting member 40d restricts the swing range of the separating flapper 40 on the flapper shaft 40b in the directions indicated by the arrows F1 and F2. In other words, in a case where the arm member 4 is located at one turn position in directions indicated by arrows A1 and A2, the posture of the separating flapper 40 located on the arm member 4 is restricted to one. Consequently, a supply path having a predetermined vertical width in
During the supplying operation of the sheet 1, the sheet 1 intrudes between the guide 4b of the arm member 4 and the slide member 40a. Therefore, the sheet 1 pushes up the separating flapper 40 by its thickness while being supplied through the supply path defined between the guide 4b of the arm member 4 and the guide surface 41c of the separating flapper 40. The supply path is formed in a predetermined width, as described above, thereby suppressing any buckling of the sheet such as a low rigidity sheet or a thin sheet.
The arm member 4 is pressed by the torsion coil spring 3c all the time in the direction indicated by the arrow A1. Consequently, as the outer diameter of the sheet roll R is reduced, as shown in
In a case where there is a large clearance between the sheet roll R and a tip end 40e of the separating flapper 40, in the case of, particularly, a sheet 1 having a large curl, the tip end of the sheet 1 is wound around the sheet roll R, whereby the sheet 1 possibly hardly intrudes into a sheet supply port between the arm member 4 and the separating flapper 40. In view of this, the small clearance between the sheet roll R and the tip end 40e of the separating flapper 40 is desired. In the present embodiment, as the outer diameter of the sheet roll R becomes smaller, the tip end 40e of the separating flapper 40 approaches the center of the sheet roll R according to the turn of the support arm 41a, the swing of the separating flapper 40, and the movement of the restricting member 40d, as shown in
The present embodiment is configured such that as the outer diameter of the sheet roll R changes from a large diameter shown in
The curl of the sheet 1 becomes stronger as the outer diameter of the sheet roll R becomes smaller. However, the driven roller 8 moves as the outer diameter becomes smaller, and then, the supply direction of the sheet 1 along a tangent at the point P2 changes downward and rightward in
The drive unit 50 moves the rotary shaft 5 in the direction indicated by the arrow H1 reverse to the supply direction of the sheet 1 as the outer diameter of the sheet roll R becomes smaller. In this manner, as the roll outer diameter becomes smaller, the contact point P2 is shifted upstream in the supply direction along the circumference of the sheet roll R. Therefore, the supply direction of the sheet 1 along the tangent at the contact point P2 changes to be oriented downward and rightward in
In the present embodiment, as shown in
As described above, the separating flapper 10 swings in the direction indicated by the arrow B1 by its own weight, and is slightly pressed against the sheet roll R via the driven roller 10a. Damage may be exerted on the sheet 1 due to the contact of the sheet 1 with the driven roller 10a depending on the type of sheet 1. In the case of, in particular, a sheet 1 that is liable to be scarred or recessed, the sheet 1 is susceptible to damage. In a case where damage is exerted on a side of the sheet 1, on which an image is printed, the image is possibly degraded. In view of this, in a case where a sheet 1 that is susceptible to damage is supplied, it is desirable that the separating flapper 10 should retract from the sheet roll R, as shown in
In the present embodiment, the separating flappers 10 are associated with each other. In each of the separating flappers 10, a cam face 10e is formed at an arm 10d between the rotary shaft 11 and the driven roller 10a. A corresponding cam 10g acts on the cam face 10e. The cam 10g can slide in directions indicated by arrows J1 and J2 in the widthwise direction (i.e., an X-axial direction) of the sheet roll R. Upon abutment of the cam 10g on the cam face 10e caused by the slide of the cam 10g in the direction indicated by the arrow J1, the separating flapper swings in the direction indicated by the arrow B2 against its own weight. In contrast, upon separation of the cam 10g from the cam face 10e caused by the slide of cam 10g in the direction indicated by the arrow J2, the separating flapper 10 is allowed to swing in the direction indicated by the arrow B1 by its own weight.
The cams 10g corresponding to the separating flappers 10 are connected to each other in such a manner as to slide in association with each other. When a user operates a lever, not shown, in one direction, all of the cams 10g slide at the same time in the direction indicated by the arrow J1 by the resultant operational force, thereby abutting on the corresponding cam faces 10e, respectively. As a consequence, as shown in
In the present embodiment, the user manually operates the lever, as required, so that the separating flapper 10 is separated from the sheet roll R, as shown in
In a case where the driven roller 10a is kept to abut against the sheet roll R while the sheet roll R is accidentally rotated in the direction indicated by the arrow C1 in the state in which the tip of the sheet 1 has not yet been separated from the sheet roll R, the tip of the sheet 1 is forcibly separated from the sheet roll R. In this case, damage is possibly exerted on the sheet 1. For example, the sheet roll R is stored in the state in which the tip of the sheet 1 is taped to the outer periphery of the sheet roll R and at one portion of the center of the tip of the sheet 1 in the widthwise direction (or restrained by a raveling preventing band or the like). In a case where the sheet roll R is accidentally rotated in the direction indicated by the arrow C1 in the above-described storage state after the sheet roll R in the storage state is set at the printing apparatus, the sheet 1 is possibly torn. Specifically, the tip of the sheet 1 is forcibly separated from the sheet roll R within a range in which the sheet 1 is not fixed or restrained (in this case, both sides apart from the center in the widthwise direction), to be possibly torn.
In consideration of the above-described case, as shown in
In the present embodiment, as shown in
The sheet roll R is set in the upper supplying apparatus 200 serving as the supplying unit by a spool member 2(1) shown in
In contrast, a sheet core 27 is set in the lower supplying apparatus 200 used as the winding unit by a spool member 2(2) shown in
In the spool member 2(1) for supplying the sheet 1, an inside end of the flange attachment 26 provided for the spool member 2(1) is a flat face 26a. Therefore, the edge of the sheet roll R abuts against the flat face 26a so that the sheet roll R can be positioned in the widthwise direction. The flat face 26a may not always be formed on the spool flange 24 on the non-reference side. The flange attachment 26 may be removed from the spool flange 24 on the non-reference side, and then, the spool member 2(1) is used as the spool member 2(2) for winding the sheet. In the meantime, a distance between the spool flanges 23 and 24 is set to be greater than the width of the sheet 1 in the spool member 2(2) for winding the sheet 1, and further, the guide faces 23a and 24a are tapered. As a consequence, skewing of the sheet 1 to be wound around the sheet core 27 is permitted to some extent.
The upper and lower supplying apparatuses 200 are provided with sensors (e.g., reflection type sensors) 128 for detecting the flange attachments 26, respectively. The CPU 201 (see
In the present embodiment, as shown in
The sheet discharging guide 61 can be turned on a shaft 61a in directions indicated by arrows K1 and K2. The sheet discharging guide 61 is turned to a position shown in
The basket 62 includes rods 63a, 63b, 63c, and 63d and a cloth member 64 having portions 64a to 64c. The rod 63d is joined to the rod 63c. Two pairs of joints, each having the rods 63c and 63d, are arranged on both sides in the widthwise direction of the sheet 1 (i.e., as viewed from the obverse to the reverse in the sheet of
The base end of the rod 63c is attached to the member 65 on the side of the printing apparatus 100 in a manner turnable in the directions indicated by the arrows M1 and M2, and furthermore, is attached in a manner slidable in directions indicated by horizontal arrows N1 and N2. In a case where the basket 62 is not used, the rod 63c is turned in the direction indicated by the arrow M2, as depicted by a solid line in
In the present embodiment, as shown in
First, the spool member 2(2) is inserted into the sheet core 27, and then, the spool member 2(2) is set at the spool holder 31 (see
Thereafter, like in the above-described embodiments, the sheet 1 supplied from the sheet roll R set at the upper supplying apparatus 200 is conveyed. Specifically, the conveyance roller 14 is rotated forward in the direction indicated by the arrow D1 by the conveyance roller driving motor 35 (see
The separating flapper 10 is kept in the state in which the separating flapper 10 is allowed to be turned in the direction indicated by the arrow B1 by its own weight, as shown in
The switch of the status of the separating flapper 10 according to the inward wound set and the outward wound set of the sheet 1 produces the following advantages.
In a case where the sheet 1 is inward set, as shown in
In contrast, in a case where the sheet 1 is set outward, as shown in
In this manner, the tip of the sheet 1 is inserted between the sheet core 27 and the driven rollers 8 and 9, and then, the user operates the operation panel 28, so that the driven rollers 8 and 9 in the lower supplying apparatus 200 press the sheet core 27 (step S27). Specifically, the arm member 4 is turned by the drive unit 3 in the direction indicated by the arrow A1. Moreover, in a case where the separating flapper 10 is in the press-contact state, the user moves the separating flapper 10 to the separate position.
Thereafter, the conveyance roller driving motor rotates the conveyance roller 14 reversely in the direction indicated by the arrow D2, and furthermore, the roll driving motor 33 at the lower supplying apparatus 200 rotates the sheet core 27 in the sheet winding direction together with the spool member 2(2) (step S28). In the case of the inward setting of the sheet 1, as shown in
The above-described feedback of the sheet 1 applies tension onto the sheet 1. The sheet 1 is fed back with the application of tension, thereby eliminating sag on the sheet 1 to be wound around the sheet core 27 so as to correct skewing. After the sheet 1 is fed back by predetermined amount, the tip of the sheet 1 is taped to the sheet core 27 (step S30), thus completing the setting of the sheet 1, whereby the apparatus 200 stands by (step S31). When the sheet 1 is fed back by predetermined amount, the tip of the sheet 1 is moved to a position at which it is readily fixed to the sheet core 27.
Upon receipt of print data from a host apparatus such as a personal computer, the conveyance roller 14 is rotated in the direction indicated by the arrow D1 in the printing apparatus 100, and further, the sheet core 27 in the lower supplying apparatus 200 is rotated in the sheet winding direction (step S42). In this manner, the sheet 1 is conveyed by predetermined amount (step S43), and then, the driven rollers 8 and 9 in the lower supplying apparatus 200 are separated from the sheet core 27 by the drive unit (step S44), and thus, printing an image is started (step S45). The roll driving motor 33 in the lower supplying apparatus 200 rotates the sheet core 27 together with the spool member 2(2) in the winding direction according to the conveying operation of the sheet 1 by the conveyance roller 14, and thus, the sheet 1 is wound up. At this time, a drive current to the roll driving motor 33 is restricted to controllably prevent the sheet 1 from being pulled by a torque (i.e., tension) more than or equal to a predetermined torque. With this control, the sheet 1 can be stably conveyed. Should the tension more than required occur, the conveyance accuracy of the sheet 1 is reduced. After the completion of the printing operation, the printing apparatus 100 stands for a similar printing operation, that is, operation for printing an image on the sheet 1 while winding the sheet 1 around the sheet core 27 (step S46).
Next, explanation will be made on the operations of the driven rollers 8 and 9 and the separating flapper 10 during the above-described printing operation.
In the present embodiment, the driven rollers 8 and 9 and the separating flapper 10 are separated from the sheet 1 to be wound around the sheet core 27. However, in the case of winding a sheet having a high rigidity in the inward wound manner, the sheet 1 need be wound against a strong curl. During the sheet winding, “winding looseness,” meaning unwinding of the once wound sheet, possibly occurs. In the meantime, in the printing apparatus requiring miniaturization and cost reduction need wind sheets having various rigidities, thicknesses, and weights at limited motor torques. In a case where such sheets are wound, the driven rollers 8 and 9 and the separating flapper 10 are brought into press-contact with the sheet, thereby suppressing the occurrence of “winding looseness” of the sheet even by using a low torque motor. Moreover, the driven rollers 8 and 9 and the separating flapper 10 are brought into the press-contact state in this manner, thus suppressing an expanding force of the sheet to be wound around the sheet core 27, so as to stabilize the winding operation. In the case of, in particular, the inward sheet winding, the driven rollers 8 and 9 are brought into press-contact with a non-print side of the sheet, so that little adverse influence is exerted on an image print side. In the same manner, the separating flapper 10 is brought into press-contact with the sheet, thus suppressing the occurrence of the “winding looseness” of the sheet. In order to enhance the suppression effect of the “winding looseness” of the sheet, the separating flapper 10 may be brought into press-contact with the sheet by not the weight of the separating flapper 10 but an urging member such as a spring, not shown.
In contrast, in the case of winding a sheet having a low rigidity and a fine surface, it is desirable that the driven rollers 8 and 9 and the separating flapper 10 should be separated from the sheet. The press-contact or separation of the driven rollers 8 and 9 and the separating flapper 10 with or from the sheet may be switched according to the physical properties of the sheet (such as a rigidity, a thickness, and a weight), the sheet winding direction (i.e., inward or outward winding), a sheet surface condition, ambient temperature, and the like. Consequently, various kinds of sheets can be wound in an optimal state.
A user instructs the start of the processing for a rear end of the sheet 1 via the operation panel 28. In this manner, the conveyance roller 14 is rotated forward in the direction indicated by the arrow D1 by the conveyance roller driving motor 35, and furthermore, the sheet core 27 is rotated in the sheet winding direction together with the spool member 2(2) by the roll driving motor 33 in the lower supplying apparatus 200 (step S51). In this manner, after the sheet 1 is conveyed by predetermined amount while the sheet 1 is wound (step S52), the drive unit 3 in the lower supplying apparatus 200 presses the driven rollers 8 and 9 against the sheet core 27 (step S53).
At this time, in a case where the driven rollers 8 and 9 are brought into contact with the image print side of the sheet 1, ink is possibly transferred thereonto. In view of this, in step S52, it is desirable that the sheet 1 should be conveyed by predetermined amount so that the image print side of the sheet 1 should be shifted downstream of the driven rollers 8 and 9 in the conveyance direction such that the driven rollers 8 and 9 are not brought into contact with the print side. In a case where the contact of the driven rollers 8 and 9 with the print side of the sheet 1 is inevitable, the print side may be sufficiently dried, before the driven rollers 8 and 9 are brought into contact with the print side. Alternatively, the print side of the sheet 1 may be subjected to treatment such as fluorine coating, before the driven rollers 8 and 9 are brought into contact with the print side.
Thereafter, the cutter 20 is driven by a cutter driving motor, not shown, to cut the sheet 1 (step S54). When the sheet 1 is cut, a user may hold a rear end of the sheet 1 wound around the sheet core 27 so as to prevent the falling of the rear end of the sheet 1. Thereafter, upon operation of the operation panel 28 by the user, the sheet core 27 is rotated in the sheet winding direction by the roll driving motor 33 in the lower supplying apparatus 200 (step S55). In this manner, the rear end of the sheet 1 is wound around the sheet core 27. After that, the rear end of the sheet 1 is taped onto the sheet core 27, thereby completing the processing for the rear end of the sheet, so that the printing apparatus comes to a standby state (step S56).
As described above, in step S53 onwards, the driven rollers 8 and 9 are pressed against the surface of the sheet 1 wound around the sheet core 27. As a consequence, between steps S54 to S56, even in a case where sag occurs on the sheet 1 between the rear end of the sheet 1 and a position at which the driven rollers 8 and 9 are pressed against the sheet 1, no winding looseness caused by the sag occurs on the sheet 1 wound around the sheet core 27. With the above-described function of the driven rollers 8 and 9, the user need not take special care of the looseness of the sheet 1 wound around the sheet core 27. In addition, the user need not tightly wind a loosened sheet 1, and therefore, in tightly winding a sheet 1, the print side of the sheet 1 does not rug, thus preventing any occurrence of a rugged scar. Additionally, the lower supplying apparatus 200 functions also as a winding apparatus for the sheet 1.
Like in the above-described first embodiment, each of upper and lower supplying apparatuses 200 is provided with the sheet sensor 6. In the following explanation, as shown in
In the present embodiment, encoders (i.e., roll rotational amount detecting sensors) 36a and 36b for detecting the rotational amounts of the roll driving motors 33a and 33b are provided for the roll driving motors 33a and 33b, respectively. The CPU 201 detects a feed speed of the tip of the sheet 1 to be fed from the sheet roll R in response to detection signals from the encoders 36a and 36b. Moreover, the CPU 201 controls, based on the feed speed of the tip of the sheet 1, a conveyance speed of the sheet 1 at a time when the tip of the sheet 1 intrudes between the conveyance roller 14 and the nip roller 15.
In step S3, like in
In a case where a sheet sensor 16 detects the tip of the sheet 1 fed according to the rotation of the sheet roll R in the direction indicated by the arrow C1, the CPU 201 calculates a radius r1 of the sheet roll R based on a count of the encoder pulses until that moment (steps S71 and S72). Unless the sheet sensor 16 detects the tip of the sheet after a lapse of a predetermined time, the CPU 201 determines a sheet feed timeout error, thus urging the user to reset the sheet 1 (step S76).
The CPU 201 calculates the radius r1 of the sheet roll R in accordance with the following equation (1).
r1=L1/2πN (1)
Where, L1 (see
The CPU 201 calculates a feed speed V1 (=rω) of the sheet 1 based on the radius r1 and a rotational angular speed ω of the sheet roll R obtained from the rotational number N of the sheet roll R, and then, sets the speed V1 as the conveyance speed of the conveyance roller 14 (step S73). And then, the CPU 201 drives the conveyance roller 14, and furthermore, sets its conveyance speed as the feed speed V1 of the sheet 1 (step S74), thus reducing a shock caused by the intrusion of the tip of the sheet 1 between the conveyance roller 14 and the nip roller 15. As a consequence, the conveyance roller 14 and the nip roller 15 can securely pick up the tip of the sheet 1 (step S75), thereby suppressing occurrence of a jam.
Thereafter, like in
In addition, in a case where the sheet 1 is supplied from the sheet roll R set in the lower supplying apparatus 200, the CPU 201 can calculate a radius r2 of the sheet roll R in accordance with the following equation (2).
r2=L2/2πN (2)
Where, L2 (see
In this manner, the CPU 201 is equipped with both a function as a detector unit for detecting the feed speed of the tip of the sheet 1 and a function as a control unit for controlling the conveyance speed of the conveyance roller 14 based on the feed speed. Here, the feed speed of the tip of the sheet 1 may be input by an external detector unit. The calculated radius of the sheet roll may be used for other control.
The printing apparatus is not limited to only the configuration provided with the two sheet supplying apparatuses corresponding to the two sheet rolls, but it may be provided with a single sheet supplying apparatus or three or more sheet supplying apparatuses. Moreover, the printing apparatus is simply required to print an image on the sheet supplied by the sheet supplying apparatus, and therefore, it is not limited to only the ink jet printing apparatus. Furthermore, the print system and configuration of a printing apparatus are arbitrary. For example, the printing apparatus may be either of a serial scan system, in which printing/scanning by a print head and a sheet conveying operation are repeated so as to print an image, or of a full line system, in which a sheet is sequentially conveyed to a position facing an elongated print head so as to print an image.
The present invention is applicable to various kinds of sheet supplying apparatuses in addition to a sheet supplying apparatus for supplying a sheet serving as a print medium to a printing apparatus. For example, the present invention is applicable to an apparatus for supplying a sheet to be read to a reader such as a scanner or a copying machine, an apparatus for supplying sheet-like workpiece to a machining device such as a cutter, and the like. The above-described sheet supplying apparatuses may be configured independently of the printing apparatus, the reader, the machining device, and the like, and further, may be provided with a control unit (i.e., a CPU) for the sheet supplying apparatus.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application is a Divisional application of U.S. patent application Ser. No. 14/939,115, filed on Nov. 12, 2015, and allowed on Oct. 20, 2016, which claims the benefit of Japanese Patent Applications No. 2014-234755, filed Nov. 19, 2014, No. 2015-165838, filed Aug. 25, 2015 which are hereby incorporated by reference wherein in their entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014-234755 | Nov 2014 | JP | national |
| 2015-165838 | Aug 2015 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14939115 | Nov 2015 | US |
| Child | 15408711 | US |
