The present invention relates to a sheet supplying apparatus and a printing apparatus which are capable of pulling a sheet out of a roll on which a continuous sheet is wound and supplying the sheet.
A printing apparatus that detects a sheet leading end of an installed roll sheet (hereinafter also referred to simply as a “roll”) and automatically feeds the sheet is disclosed in Japanese Patent Laid-Open No. 2011-37557. In this apparatus, the sheet leading end is detected through an optical sensor while causing the roll to rotate in a winding direction opposite to a supply direction, and when the detection is completed, the roll is caused to rotate in the supply direction, and the sheet separated from the roll (hereinafter also referred to as “peeling”) is fed to the inside of the apparatus.
In a case in which the roll set in a sheet supplying apparatus is not tightly wound, the automatic sheet feeding may not work smoothly since the roll is loose. Depending on a type of sheet, only by removing packing of a new roll, the roll which is tightly wound becomes loose, and the diameter of the roll expands. Therefore, the user should check that the roll to be set is not loose and then work carefully so that the roll does not become loose even when the roll is set in the apparatus. Any means for solving such a problem is not disclosed in Japanese Patent Laid-Open No. 2011-37557.
It is an object of the present invention to provide a sheet supplying apparatus and a printing apparatus which are capable of winding the roll set by a user tightly.
A sheet supplying apparatus according to the present invention includes a driving unit configured to cause a roll including a wound consecutive sheet to rotate in a first direction for feeding the sheet or a second direction opposite to the first direction, a sensor that detects a leading end portion of the sheet separated from an outer circumferential surface of the roll, and a contact body that presses the outer circumferential surface, in which, before the sheet is fed, in a state in which the contact body presses the outer circumferential surface, the driving unit causes the roll to continuously rotate in the second direction until a detection cycle of the leading end portion by the sensor is smaller than a predetermined value.
Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Hereinafter, exemplary embodiments of the present invention will be described with reference to the appended drawings. First, a basic composition of the present invention will be described.
As illustrated in
The roll R is set in the roll holding unit of the supplying apparatus 200 in a state in which a spool member 2 is inserted in a hollow hole portion of the roll R, and the spool member 2 is driven by a motor 33 for driving the roll R (see
A conveyance guide 12 guides the sheet 1 to the printing unit 400 while guiding front and back surfaces of the sheet 1 pulled out from the supplying apparatus 200. A conveying roller 14 is rotated normally or reversely in directions of arrows D1 and D2 by a conveying roller driving motor 35 (see
A platen 17 of the printing unit 400 regulates the position of the sheet 1, and a cutter 20 cuts the sheet 1 on which an image is printed. A cover 42 of the roll R prevents the sheet 1 on which an image is printed from entering the supplying apparatus 200. The operation in the printing apparatus 100 is controlled by a CPU 201 (see
The swing member 7 is swingably attached to the arm member 4, and the first and second driving rotating bodies (rotating bodies) 8 and 9 which are positioned to deviate in a circumferential direction of the roll R are rotatably mounted to the swing member 7. The driving rotating bodies 8 and 9 move in accordance with an outer shape of the roll R and come into pressure contact with the outer circumferential portion of the roll R from a lower side in the gravity direction in accordance with pressing force against the arm member 4 in the direction of arrow A1. In other words, the driving rotating bodies 8 and 9 come into pressure contact with the outer circumference portion of the roll R from a lower side in the gravity direction than a central shaft of the roll R in the horizontal direction. The pressure contact force is changed in accordance with pressing force of pressing the arm member 4 in the direction of arrow A1.
A plurality of arm members 4 each including the swing member 7 are provided at a plurality of different positions in the X-axis direction. As illustrated in
The bearing portion 7a is provided at a gravity center position of the swing member 7 and supported by the rotational shaft 4a so that the swing member 7 has a stable attitude in each of the X-axis direction, the Y-axis direction, and the Z-axis direction. Further, since the rotational shaft 4a is accepted with looseness, any of a plurality of swing members 7 are displaced along the outer circumference portion of the roll R depending on the pressing force against the arm member 4 in the direction of the arrow A1. With such a configuration (equalizing mechanism), a change in a pressure contact attitude of the first and second driving rotating bodies 8 and 9 with respect to the outer circumferential portion of the roll R is permitted. As a result, a contact region between the sheet 1 and the first and second driving rotating bodies 8 and 9 is kept at maximum, and the pressing force against the sheet 1 is equalized, and thus a variation the conveyance force of the sheet 1 can be suppressed. Since the driving rotating bodies 8 and 9 come into pressure contact with the outer circumference portion of the roll R, the occurrence of slack in the sheet 1 is suppressed, and conveyance force thereof is enhanced.
In a main body of the printing apparatus 100 (printer main body), the separating flapper 10 positioned above the arm member 4 is attached to be rotatable on the flapper rotational shaft 11 in the directions of the arrows B1 and B2. The separating flapper 10 is configured to lightly press an outer circumferential surface of the roll R by its own weight. In a case in which it is necessary to more strongly press the roll R, biasing force by a biasing member such as a spring may be used. A driven roller (upper contact body) 10a is rotatably provided at a contact portion of the separating flapper 10 with the roll R to suppress influence of the pressing force on the sheet 1. A separating portion 10b of the leading end of the separating flapper 10 is formed to extend up to a position as close to the outer circumferential surface of the roll R as possible in order to facilitate the separation of the leading end portion of the sheet from the roll R.
The sheet 1 is supplied through the supply path formed between the separating flapper 10 and the arm member 4 after the front surface (print surface) of the sheet is guided by the upper guide portion 4b of the arm member 4. Accordingly, it is possible to smoothly supply the sheet 1 using the weight of the sheet 1. Further, since the driving rotating bodies 8 and 9 and the guide portion 4 are moved depending on the outer diameter of the roll R, it is possible to reliably pull out the sheet 1 from the roll R and convey the sheet even when the outer diameter of the roll R changes.
One of the features of the apparatus according to the present embodiment lies in an automatic sheet loading function (an automatic sheet feeding function). In the automatic loading, when the user sets the roll R in the apparatus, the apparatus detects the leading end of the sheet while rotating the roll R in a direction (which is referred to as an opposite direction or a second direction, a direction of arrow C2 in
Further, the printing apparatus 100 of the present example includes the two upper and lower supplying apparatuses 200, and it is possible to perform switching from a state in which the sheet 1 is supplied from one supplying apparatus 200 to a state in which the sheet 1 is supplied from the other supplying apparatus 200. In this case, one supplying apparatus 200 rewinds the sheet 1 which has been supplied so far on the roll R. The leading end portion of the sheet 1 is evacuated up to the position at which the leading end thereof is detected by the sensor unit 6.
The CPU 201 of the printing apparatus 100 stands by in a state in which the arm member 4 is pressed in the direction of the arrow A1 by “weak pressing force” (a weak nip state), and first determines whether or not the roll R is set (step S1). In the present example, when the roll sensor 32 detects the spool member 2 of the roll R, the roll R is determined to be set. After the roll R is set, the CPU 201 switches a state in which the arm member 4 is pressed in the direction of the arrow A1 by “strong pressing force” (a strong nip state) (step S2). Then, the CPU 201 executes a leading end portion setting process in which the leading end portion of the sheet 1 is set in the sheet supply path between the arm member 4 and the separating flapper 10 (step S3). With the leading end portion setting process (automatic loading), the leading end portion of the sheet 1 is set (inserted) in the sheet supply path. The leading end portion setting process will be described later in detail.
Thereafter, the CPU 201 rotates the roll R in the direction of the arrow Cl by the roll driving motor 33 and starts supplying the sheet 1 (step S4). When the leading end of the sheet 1 is detected by a sheet sensor 16 (step S5), the CPU 201 normally rotates the conveying roller 14 in a direction of arrow D1, picks up the leading end portion of the sheet 1, and then stops the motor 33 and the motor 35 (step S6). Thereafter, the CPU 201 cancels the pressing force of pressing the arm member 4 in the direction of arrow A1, and causes the first and second driven rotating bodies 8 and 9 to be separated from the roll R (to enter a nip release state) (step S7).
Thereafter, the CPU 201 determines whether the sheet is conveyed (skewed) in a state in which the sheet is obliquely inclined in the sheet conveying unit 300. Specifically, the sheet 1 is conveyed by a predetermined amount in the sheet conveying unit 300, and an amount of skew occurring at that time is detected by a sensor installed in a carriage including the print head 18 or installed in the sheet conveying unit 300. When the amount of skew is larger than a predetermined allowable amount, the sheet 1 is repeatedly fed or back-fed with the normal rotation and the reverse rotation of the conveying roller 14 and the roll R while applying back tension to the sheet 1. With this operation, the skew of the sheet 1 is corrected (step S8). As described above, when the skew of the sheet 1 is corrected or when an operation of printing an image on the sheet 1 is performed, the supplying apparatus 200 is set to enter the nip release state. Thereafter, the CPU 201 causes the sheet conveying unit 300 to move the leading end of the sheet 1 to a standby position (a fixed position) before printing starts in the printing unit 400 (step S9). Accordingly, the preparation for supplying the sheet 1 is completed. Thereafter, the sheet 1 is pulled out from the roll R with the rotation of the roll R and conveyed to the printing unit 400 by the sheet conveying unit 300.
An embodiment of the leading end portion setting process (step S3 in
A basic procedure of winding tightly is as follows. The roll is caused to perform more than one rotation in the opposite direction (the direction of arrow C2) prior to the sheet feeding operation. During the time, the roll is caused to rotate in the opposite direction continuously until a detection cycle in which the sensor detects the sheet leading end portion twice or more falls within a predetermined allowable range. With this operation, the roll R is tightly wound on the apparatus, and thus the loose roll R is tightened. After this operation, the automatic sheet feeding is performed. This will be described in detail below.
The sensor unit 6 according to the present embodiment will be described below with reference to
The leading end portion setting process (step S3 in
First, the CPU 201 starts acquisition of the output value of the sensor unit 6 (step S31), and causes the roll R to rotate in an opposite direction (in the direction of arrow C2) (step S32). Then, the CPU 201 detects a change (inversion) from a high level (hereinafter an “H level”) to a low level (hereinafter an “L level”) in the output of the sensor unit 6 (step S33).
Here,
In a case in which the rotation is continued thereafter, the leading end of the sheet 1 passes over the sensor unit 6 at a time point at which the rotational angle exceeds 200° and enters a state as illustrated in
The H level and L level indicate the levels to which the output values of the sensor unit 6 belong. The output of the sensor unit 6 having the H level indicates that the distance between the sensor unit 6 and the reflecting surface is short, and the output of the sensor unit 6 having the L level indicates that the distance between the sensor unit 6 and the reflecting surface is long. A leading end detection threshold value TH used for determining whether the output of the sensor unit 6 is the H level or the L level is stored in a non-volatile memory in the printer main body or the sensor unit. In this example, the threshold value TH is set to TH=(H0+L0)/2. Here, L0 is an output value of the sensor unit 6 when the leading end portion of the sheet 1 is positioned between the driven rotating body 8 and the sensor unit 6 (
The description returns to the flow of
In a case in which the roll R is determined not to be loose in the automatic tightening process (step S34), the CPU 201 causes the rotation of the spool member 2 to continue. Then, the CPU 201 determines whether or not the output of the sensor unit 6 maintains the state of the L level even when the roll R is caused to rotate by a predetermined rotational angle or more (this rotational angle is assumed to be “A”) from the state immediately after the leading end of the sheet 1 has passed over the sensor unit 6 (step S35). Here, the predetermined rotational angle A is determined to satisfy θ′>A on the basis of an angle (θ′) formed by a straight line connecting a rotation center C with the sensor unit 6 and a straight line connecting the rotation center C and the driven rotating body 8. In this example, A=θ′/2. In a case in which YES is determined in step S35, the CPU 201 causes the rotation of the roll R to be stopped (step S36). At this time, the leading end of the sheet 1 is positioned between the driven roller 10a and the arm member 4. Therefore, the CPU 201 then causes the spool member 2 to rotate in the forward direction (the direction of the arrow C2) (step S37), so that the leading end portion of the sheet 1 can pass through between the arm member 4 and the separating flapper 10 and be guided to the inside of the sheet supply path.
In a case in which NO is determined in step S33 or step S35, the CPU 201 determines whether or not the roll R has performed three or more rotations from a rotation start time point (step S38). In a case in which NO is determined in step S38, the process returns to step S33, and on the other hand, in a case in which YES is determined, the CPU 201 stops the rotation of the roll R and the inversion detection of the output of the sensor unit 6 and urges the user to perform a manual manipulation (manual sheet feeding). Specifically, since the automatic sheet feeding has failed, a message for urging the user to perform the manual sheet feeding is displayed on the manipulation panel 28 (step S39). In this example, it is determined in step S38 whether or not the roll R has performed three or more rotations, but a threshold value used for determining whether or not the roll R has performed a predetermined number of rotations or more is not limited to 3 and may be arbitrarily set. The content of the leading end portion setting process according to the present embodiment has been described above.
In a case in which the roll is set in the printing apparatus through the leading end portion setting process according to the present embodiment, the loose roll is automatically tightened, and then the leading end portion of the sheet is guided to the inside of the sheet supply path. Therefore, the user need not manually tighten the sheet after setting the roll and need not set the leading end portion of the sheet in the sheet supply path. Thus, the convenience in the case of setting the roll is improved.
Hereinafter, the automatic tightening process (S34 in
The automatic tightening process starts in a state in which the roll R is caused to rotate in the opposite direction. First, the CPU 201 reads a rotational angle (referred to as “Q1”) of the shaft of the roll R at a timing at which an immediately previous output of the sensor unit 6 changes from the H level to the L level through the roll rotation amount sensor 36 and stores the read rotational angle in a volatile memory (step S341). Then, the CPU 201 causes the rotation to continue in a state the driven rotating bodies 8 and 9 come into pressure contact with the outer peripheral portion of the roll R. Then, in a case in which the roll R is loose, a sheet surface portion is wound up on the roll R, and the loose roll R is tightly wound (see a surface portion 1a of
A case in which the change from the H level to the L level in the output of sensor unit 6 is detected (YES in step S342) will be described below. In this case, the CPU 201 reads a rotational angle (referred to as “Q2”) of the shaft of the roll R at a timing at which an immediately previous output of the sensor unit 6 changes from the H level to the L level through the roll rotation amount sensor 36 and stores the read rotational angle in the volatile memory (step S343).
Here, the reason for acquiring Q1 and Q2 will be described. In a case in which the loose roll R is tightly wound as illustrated in
The angle B may be set to a predetermined angle of 360° or more in view of a reading accuracy of the sensor unit 6 or uncertainty of a motion of the leading end portion of the sheet 1. In the present embodiment, the angle B is set to 370°, the sequence is continued until the angular phase difference between Q2 and Q1 becomes less than 370° while overwriting Q1 and Q2, and thus the roll sheet can be automatically tightly wound.
The description returns to the flow of
In a case in which NO is determined in step S344, the CPU 201 determines whether or not Q2−Q1<370° is satisfied (step S345) using Q1 acquired in step S341 and Q2 acquired in step S343. In a case in which YES is determined in step S345, the roll R is determined not to be loose, the automatic tightening process ends, and the process proceeds to step S35 of
Next, a case in which the change from the H level to the L level in the output of the sensor unit 6 is not detected (NO in step S342) will be described. In this case, the CPU 201 determines whether or not the roll R has performed three or more rotations from the rotation start time point (step S346). In a case in which YES is determined in step S346, the process proceeds to step S347, whereas in a case in which NO is determined, the process returns to step S342. Here, the threshold value of the number of rotations used for the determination criterion in step S346 may be set arbitrarily.
In a case in which YES is determined in step S344 or step S346, the CPU 201 stops the automatic tightening process, causes a message for prompting the user to perform the manual sheet feeding to be displayed the manipulation panel 28 (step S347), and ends a series of processes. The content of the automatic tightening process according to the present embodiment has been described above.
In the present embodiment, the leading end of the sheet is specified twice or more, and the roll is caused to rotate in the opposite direction until a phase difference thereof becomes less than a certain value (until the detection cycle falls within a predetermined allowable range), and thus the loose roll can be automatically tightly wound. Accordingly, the user need not tightly wind the loose roll with his/her own hand. Accordingly, the convenience in the case of setting the roll is improved. Further, the roll is caused to rotate in the forward direction after the tightly winding operation, and thus it is possible to reliably guide the leading end portion of the sheet to the sheet feeding opening, leading to an improvement in the reliability of the automatic sheet feeding.
As the sensor unit 6, a distance sensor other than an optical sensor can be used as long as the sensor has an output value changing according to a distance to the sheet. For example, a distance sensor such as an ultrasonic sensor or an electrostatic sensor that detects the distance to the object in a non-contact manner can be used.
The printing apparatus is not limited to the configuration including the two sheet supplying apparatuses corresponding to the two roll sheets and may be a configuration including one sheet supplying apparatus or three or more sheet supplying apparatuses. Further, the printing apparatus is not limited to only the inkjet printing apparatus as long as an image can be printed on a sheet supplied from the sheet supplying apparatus. Further, the printing system and configuration of the printing apparatus are arbitrary as well. For example, a serial scan system of repeating scanning of the print head and the sheet conveyance operation and printing an image or a full-line system of continuously conveying a sheet to a position opposite to a long print head and printing an image may be employed.
Further, the present invention can be applied to various sheet supplying apparatuses in addition to the sheet supplying apparatus which supplies sheets serving as print medium to the printing apparatus. For example, the present invention can be applied to an apparatus that supplies a reading target sheet to a reading apparatus such as a scanner or a copying machine, an apparatus that supplies a sheet-like processing material to a processing apparatus such as a cutting apparatus. Such a sheet supplying apparatus may be configured separately from an apparatus such as the printing apparatus, the reading apparatus, or the processing apparatus and may include a control unit (CPU) for the sheet supplying apparatus.
Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
According to the present invention, the roll set by the user is tightened by the apparatus, and its looseness is eliminated. Accordingly, the work load of the user is reduced.
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 claims the benefit of Japanese Patent Application No. 2017-046418 filed Mar. 10, 2017, which is hereby incorporated by reference wherein in its entirety.
Number | Date | Country | Kind |
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2017-046418 | Mar 2017 | JP | national |
Number | Date | Country | |
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Parent | 15910489 | Mar 2018 | US |
Child | 17069183 | US |
Number | Date | Country | |
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Parent | 18096826 | Jan 2023 | US |
Child | 18756279 | US | |
Parent | 17069183 | Oct 2020 | US |
Child | 18096826 | US |