1. Technical Field
The present invention relates to a printing device, a printing method, and a program.
2. Related Art
There is an ink jet printer of a type using wide paper with a paper size of A2 or more. In such an ink jet printer using the wide paper, there are many cases of using so-called roll paper in addition to cut paper. The paper (a part coming from the roll body) may drawn out from the roll body (so-called roll paper in which paper is rolled) by rotating the roll body using a motor. JP-A-2009-256095, JP-A-2009-280398, JP-A-2010-111057, and JP-A-2010-52931 are examples of the related art.
However, in a case of the roll body having a great amount of rolled paper, an inertia moment of the roll body itself is large. Accordingly, it is difficult to brake the roll body due to the large inertia moment, and thus the amount of looseness of the medium between the roll body and a transport roller may be larger than necessary.
An advantage of some aspects of the invention is to appropriately adjust the amount of looseness of the medium between the roll body and the transport roller.
According to an aspect of the invention, there is provided a printing device including: a driving motor that applies a driving power rotating a roll body in which a medium is rolled; a driving roller that transfers the driving power of the driving motor to the roll body; a transport motor that applies a driving power transporting the medium; a transport roller that is provided further to the downstream side than the roll body in the transport direction of the medium and transfers the driving power of the transport motor to the medium; and a looseness amount acquiring unit that acquires an amount of looseness between the driving roller and the transport roller, wherein when the amount of looseness is equal to or more than a predetermined amount of looseness, the driving motor is controlled on the basis of the amount of looseness acquired by the looseness amount acquiring unit, and when the amount of looseness is less than the predetermined amount of looseness, the driving motor is controlled on the basis of tension between the driving roller and the transport roller.
Other aspects of the invention will be made clear by the description of the specification and the accompanying drawings.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
At least the following will be made clear by the description of the specification and the accompanying drawings.
There is provided a printing device including: a driving motor that applies a driving power rotating a roll body in which a medium is rolled; a driving roller that transfers the driving power of the driving motor to the roll body; a transport motor that applies a driving power transporting the medium; a transport roller that is provided further to the downstream side than the roll body in the transport direction of the medium and transfers the driving power of the transport motor to the medium; and a looseness amount acquiring unit that acquires an amount of looseness between the driving roller and the transport roller, wherein when the amount of looseness is equal to or more than a predetermined amount of looseness, the driving motor is controlled on the basis of the amount of looseness acquired by the looseness amount acquiring unit, and when the amount of looseness is less than the predetermined amount of looseness, the driving motor is controlled on the basis of tension between the driving roller and the transport roller.
With such a configuration, it is possible to appropriately adjust the amount of looseness of the medium between the roll body and the transport roller.
In the printing device, it is preferable that the looseness amount acquiring unit acquires the amount of looseness by measuring an amount of looseness of the medium. The looseness amount acquiring unit may acquire the amount of looseness on the basis of an amount of transport of the medium transported by the driving roller and an amount of transport of the medium transported by the transport roller.
With such a configuration, it is possible to appropriately adjust the amount of looseness of the medium between the roll body and the transport roller.
There is provided a printing method of a printing device including a driving motor that applies a driving power rotating a roll body in which a medium is rolled, a driving roller that transfers the driving power of the driving motor to the roll body, a transport motor that applies a driving power transporting the medium, a transport roller that is provided further to the downstream side than the roll body in the transport direction of the medium and transfers the driving power of the transport motor to the medium, and a looseness amount acquiring unit that acquires an amount of looseness between the driving roller and the transport roller, the method including: acquiring the amount of looseness between the driving roller and the transport roller; controlling the driving motor on the basis of the amount of looseness acquired by the looseness amount acquiring unit when the amount of looseness is equal to or more than a predetermined amount of looseness; and controlling the driving motor on the basis of tension between the driving roller and the transport roller when the amount of looseness is less than the predetermined amount of looseness.
With such a configuration, it is possible to appropriately adjust the amount of looseness of the medium between the roll body and the transport roller.
A program executed on a printing device including a driving motor that applies a driving power rotating a roll body in which a medium is rolled, a driving roller that transfers the driving power of the driving motor to the roll body, a transport motor that applies a driving power transporting the medium, a transport roller that is provided further to the downstream side than the roll body in the transport direction of the medium and transfers the driving power of the transport motor to the medium, and a looseness amount acquiring unit that acquires an amount of looseness between the driving roller and the transport roller, the program causing the printing device to execute: acquiring the amount of looseness between the driving roller and the transport roller; controlling the driving motor on the basis of the amount of looseness acquired by the looseness amount acquiring unit when the amount of looseness is equal to or more than a predetermined amount of looseness; and controlling the driving motor on the basis of tension between the driving roller and the transport roller when the amount of looseness is less than the predetermined amount of looseness.
With such a configuration, it is possible to appropriately adjust the amount of looseness of the medium between the roll body and the transport roller.
Configuration of Printer
Hereinafter, a printer 10 as a printing device according to an embodiment, and a control process thereof will be described. For example, the printer 10 of the embodiment is a printer for printing of wide paper equal to or more than the A4 size of the JIS standard. The printer of the embodiment is an ink jet printer. The ink jet printer may be a device employing any ejection method if it is a device ejecting ink to perform printing.
The roll driving mechanism 30 is provided in a roll mounting portion 22 of the main body portion 20. As shown in
The RR motor 33 applies driving power (rotation power) to a rotation holders 31a positioned on one side of the pair of rotation holders 31 through the gear 32. In the embodiment, a rotary encoder is used as the rotation detecting unit 34. For this reason, the rotation detecting unit 34 includes a disc-shaped scale 34a and a rotary sensor 34b. The disc-shaped scale 34a includes light transmitting portions allowing light to pass, and light blocking portions blocking the transmission of light at a regular interval along a circumferential direction thereof. The rotary sensor 34b includes a light emitting device (not shown), a light receiving device (not shown), and a signal processing circuit (not shown), as principal constituent elements.
The carriage 41 includes an ink tank 43 for storing ink with colors (corresponding to fluid), and the ink is supplied from an ink cartridge (not shown) fixedly provided on the front side of the main body portion 20 to the ink tank 43 through a tube (not shown). As shown in
The carriage 41, the ink tank 43, the tube (not shown), the ink cartridge, and the ink head 44 constitute the ink supplying and ejecting mechanism. The printing head 44 is not limited to the piezoelectric driving type using the piezoelectric devices. For example, a heater type of using power of bubbles generated by heating ink using a heater, a magnetostrictive type of using magnetostrictive devices, and a mist type of controlling mist in an electric field may be employed. Any kind of ink such as dye ink and pigment ink may be used as the ink filling up the ink cartridge and ink tank 43.
A platen 55 is provided on the downstream side (paper discharge side) of the pair of transport rollers 51, and the paper P is guided on the platen 55. The printing head 44 is provided to be opposed to the platen 55. The platen 55 is provided with suction holes 55a. The suction holes 55a are formed to communicate with a suction fan 56, and the air is sucked from the printing head 44 through the suction holes 55a by operating the suction fan 56. Accordingly, when the paper P is placed on the platen 55, it is possible to suck and hold the paper P. In addition, the printer 10 is provided with various sensors.
The PF motor control unit 111 of the control unit 100 controls driving of the PF motor 53 to rotate the transport driving roller 51a to transport the paper P in the transport direction. Hereinafter, the direction of the rotation of the PF motor 53 when the paper P is transported in the transport direction is referred to as a forward rotation direction. The RR motor control unit 112 controls driving of the RR motor 33 to supply the paper P. The direction of the rotation of starting rolling the paper P from the roll body RP is the forward rotation direction of the RR motor 33, and the direction of the rotation reversely rolled is the reverse rotation direction. The main control unit 110 controls operations of the PF motor control unit 111 and the PR motor control unit 112. The control unit 100 performs processes in association with the main control unit 110, the PF motor control unit 111, and the RR motor control unit 112.
Control of RR Motor 33
According to the size of the roll body RP, there is a case where it is difficult to appropriately supply the paper P from the roll body RP due to the inertia moment generated from the weight thereof. Specifically, it is difficult to appropriately stop the roll body RP and more of the paper P is supplied than necessary, according to the magnitude of the inertia moment. In the embodiment, the following control is performed considering a risk when guiding the paper P too much as described above.
The horizontal axis of the graph of
In the embodiment, when the amount of looseness is larger than the threshold value, the rotation of the RR motor 33 is controlled on the basis of the acquired amount of looseness. Meanwhile, when the amount of looseness is equal to or less than the threshold value, the rotation of the RR motor 33 is controlled on the basis of the tension between the pair of transport rollers 51 and the roll body RP. The method of controlling the amount of looseness on the basis of the acquired amount of looseness (hereinafter, referred to as “management of looseness”, and the method of controlling the amount of looseness on the basis of the tension (hereinafter, referred to as “management of tension”) will be described later.
Management of Looseness
As an aspect of acquiring the amount of looseness, there is a method of using a looseness sensor 58. For example, the looseness sensor 58 is a sensor capable of detecting a position of the paper in the up and down direction. By employing such a sensor, it is possible to acquire the amount of looseness representing how much the paper P is loosened in comparison with the case where the paper P is tight.
In the management of looseness, the RR motor 33 is controlled such that the amount of looseness of the paper P is a predetermined target amount of looseness. In the embodiment, the target amount of looseness is set to 5 mm. The RR motor 33 may be controlled such that a difference obtained by reducing the acquired amount of looseness from the target amount of looseness is zero. For example, the RR motor 33 may be rotated by a duty control of performing a PID control such that the difference is zero. In such a manner, when the amount of looseness is larger than the predetermined threshold value, it may be a proper amount of looseness.
In the description, the amount of looseness of the paper P is acquired using the looseness sensor 38, but the amount of looseness of the paper P may be calculated on the basis of information obtained from the rotation detecting unit 34 of the RR motor 33 and the rotation detecting unit 54 of the PF motor 53. It is possible to obtain an amount of transport Feed_roll of the paper P from the amount of rotation of the RR motor 33 obtained from the rotation detecting unit 34 and the diameters of the gear 32 and the roll body RP. The diameter of the roll body RP may be estimated on the basis of the amount of already transported paper P. In addition, it is possible to obtain an amount of transport Feed_pf of the paper P from the amount of rotation of the PF motor 53 obtained from the rotation detecting unit 54 and the diameters of the gear 52 and the rotation holder 31. Accordingly, it is possible to estimate an amount of looseness occurring at the present time, by subtracting the amount of transport Feed_pf from the amount of transport Feed_roll.
The target amount of looseness may be varied according to the thickness of the paper. For example, in a case of thin paper, there is an advantage that the paper does not crinkle when the tension is relatively strong. In such a case, the target amount of looseness may be set to 0 mm.
Management of Tension
T×D=k1×N
T=k1×N/D (2)
In the state where the paper P is transported at the predetermined transport velocity V without driving the RR motor 33, the tension T satisfying at least the formula (1) acts. In the formula, k1 is a proportional integer, and may be specified on the basis of the diameter of the rotation shaft of the roll body RP. The relation between the transport velocity V and the roll static load N necessary to rotate the roll body RP may be obtained by advance estimation. Accordingly, it is possible to specify the tension T generated when transporting the paper P at an arbitrary transport velocity V without driving the RR motor 33.
Next, it is assumed that the RR motor 33 is driven. When the PF motor control unit 111 performs the PWM output on the RR motor 33 and the RR motor 33 generates an output torque M in the forward rotation direction, a torque obtained by subtracting the output torque M from the roll static load N acts around the rotation shaft of the roll body RP. In this case, the following formula (2) is obtained on the basis of the formula (1).
T×D=k1×(N−M)
T=k1×(N−M)/D (2)
As shown in the formula (2), it is possible to reduce the tension T acting on the paper P by forwardly rotating (M>0) the RR motor 33 while transporting the paper P. In addition, the magnitude of the tension T (amount of adjustment) reduced by the output torque M is k1×M/D. On the other hand, when the negative output torque M (reverse rotation direction) is applied to the RR motor 33, it is possible to increase the tension T. When the tension T is too large, the amount of slip between the transport driving roller 51a and the paper P is increased, and thus it is difficult to realize the intended amount of transport. The amount of slip is proportional to the tension T. When the tension T is too small, the roll body RP is spontaneously positively rotated to cause the looseness of the paper P.
In the embodiment, the target value of the tension T is set to the designated tension F. By substituting the designated tension F in the formula (2), it is possible to calculate the output torque M of the RR motor 33 necessary to realize the designated tension F. Appropriately estimated values may be used as the diameter D of the roll body RP and the roll static load used in the above (5), by a new update after each printing process. In such a manner, it is possible to accurately calculate the output torque M.
Duty=k2×M (3)
As shown in the formula (3), since the duty value of the PWM signal for generating the output torque M is proportional to the output torque M, the RR motor control unit 112 can perform the control for realizing the designated tension F. In addition, k2corresponds to the proportional constant for regulating the duty. Since the mechanical characteristics of the paper P are different according to kinds of the paper P, the designated tension F is prepared for each kind of the paper P and stored in advance in the ROM 102. In a case of thick paper P, great power is necessary for deformation for starting rolling from the rolled state on the plane, and thus it is preferable to set the designated tension F larger than that of the thin paper P.
In such a manner, it is possible to feed the paper P considering the self-propellent risk of the roll body RP generated from the rotation moment by changing the control of looseness and the control of tension, according to the amount of looseness of the paper P. That is, it is possible to appropriately adjust the amount of looseness of the paper P between the roll body and the transport roller. p Other Embodiments
In the embodiment described above, the printer 10 has been described as the liquid ejecting device, but the invention is not limited thereto. A liquid ejecting device which ejects or sends out another fluid (liquid, liquid-form material in which particles of functional materials are dispersed, and fluid such as gel) other than the ink may be embodied. For example, the same technique as described in the embodiment may be applied to various devices applying the ink jet technique, such as a color filter producing device, a dyeing device, a micro-processing device, a semiconductor producing device, a surface processing device, a 3-dimensional modeling device, a gas vaporizing device, an organic EL producing device (particularly, polymer EL producing device), a display producing device, a film forming device, and a DNA chip producing device. Such a method or a production method falls within the application scope.
A printing method of feeding the paper P in the method described above falls within the embodiment, and a program for realizing such a printing method falls within the embodiment.
The embodiments described above are to easily understand the invention, but are not to restrictively analyze the invention. The invention may be modified and improved without deviating from the concept thereof, and it is natural that the invention includes the equivalents thereof.
Number | Date | Country | Kind |
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2010-180758 | Aug 2010 | JP | national |