JP2004338108A - Ribbon cassette and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ribbon cassette and a printer in which failure of print due to crimples or slack of an ink ribbon can be prevented. <P>SOLUTION: The ribbon cassette comprises a stripe ink ribbon, a feeding shaft around which the ink ribbon is wound and a winding shaft, and a guide roller 5 in press contact with the ink ribbon. The guide roller 5 is provided, on the outer circumferecial surface thereof, with spiral grooves 5a and 5b formed in reverse directions substantially from the center thereof toward the opposite ends. The guide roller 5 is arranged with respect to the ink ribbon such that the spiral grooves 5a and 5b are directed outward from the center along the rotational direction of the guide roller 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a ribbon cassette containing an ink ribbon used for hot-melt printing or sublimation printing, and a printing apparatus.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a printing apparatus, an apparatus has been known in which a torque is applied in a reverse direction to a supply shaft for feeding an ink ribbon so that the ink ribbon runs stably (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-6-270486 (abstract, FIG. 1)
[0004]
[Problems to be solved by the invention]
However, in the above-described conventional apparatus, for example, when the recording density is shifted in the width direction perpendicular to the running direction of the ink ribbon, the balance of the ink ribbon along the width direction is lost, and the winding of the ink ribbon is performed. The winding diameter of the take-up shaft may change along the axial direction. In such a case, the ink ribbon wound by the winding shaft is slightly twisted, and the ink ribbon is wrinkled or sagged. If wrinkles or slacks occur in the ink ribbon, printing defects will occur.
[0005]
The present invention has been made in view of the above points, and an object of the present invention is to provide a ribbon cassette and a printing apparatus that can prevent a printing failure due to wrinkling or slack of an ink ribbon.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, a ribbon cassette according to the present invention includes a belt-shaped ink ribbon, first and second shafts that are rotatably provided by winding both ends of the ink ribbon, and the first and second shafts. Spiral friction that is in pressure contact with the ink ribbon running by rotation of the shaft and extends in a direction crossing the running direction of the ink ribbon, and that is spirally opposed on the outer peripheral surface from substantially the center in the axial direction to both ends. And a guide roller having a generator.
[0007]
Further, the printing apparatus of the present invention comprises a belt-shaped ink ribbon, first and second shafts rotatably provided by winding both ends of the ink ribbon, and running between the first and second shafts. A head for printing the information by pressing the ink ribbon against a recording medium, and extending in a direction crossing the running direction of the ink ribbon while being pressed against the ink ribbon, and both ends of the outer peripheral surface of the ink ribbon from substantially the center in the axial direction. And a guide roller having helical friction generating portions opposite to each other.
[0008]
According to the above invention, when the guide roller pressed against the ink ribbon rotates along the ink ribbon, the spiral friction generating portion acts to spread the ink ribbon outward from the center in the width direction crossing the running direction. To prevent wrinkles and sagging of the ink ribbon. As a result, printing defects due to wrinkles and sagging of the ink ribbon can be prevented.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0010]
FIG. 1 shows a schematic structure of a ribbon cassette 1 (hereinafter simply referred to as a cassette 1) according to an embodiment of the present invention.
[0011]
The cassette 1 has a case 2 indicated by a broken line in the figure. In the case 2, an elongated ribbon-shaped ink ribbon R, a delivery shaft 3 and a winding shaft 4 (first and second shafts) around which both ends of the ink ribbon R are wound, and two guide rollers 5, 5 are provided. Is provided. The delivery shaft 3, the take-up shaft 4, and the two guide rollers 5, 5 are respectively arranged in a predetermined positional relationship as shown in the drawing, that is, in the paper direction, that is, in the width direction orthogonal to the running direction of the ink ribbon R. And has a length exceeding at least the width of the ink ribbon R.
[0012]
More specifically, the ink ribbon R sent out from the feed shaft 3 is bent by approximately 90 ° along the guide roller 5 on the right side (upstream side) in the figure, and is bent by the guide roller 5 on the left side (downstream side) in the figure. Along the same direction, and is stretched so as to be wound by the winding shaft 4. A predetermined tension is applied to the ink ribbon R between the two guide rollers 5,5.
[0013]
When the cassette 1 is set in a printing apparatus, an ink ribbon R is interposed between the two guide rollers 5 between the thermal printer head 11 (hereinafter simply referred to as the head 11) and the platen roller 12. In other words, the case 2 is set in the printing apparatus as shown in FIG. The head 11 is provided so as to be detachable from the platen roller 12 in the direction of arrow S in the figure, and when the cassette 1 is set, the head 11 moves to a retreat position (upward in the figure) separated from the platen roller 12. Is done.
[0014]
A recording medium M on which information is printed by the printing apparatus is conveyed at the same speed in the same direction as the ink ribbon R in a state where the recording medium M faces the head 11 with the ink ribbon R interposed therebetween and the back side is supported by the platen roller 12. Is done. Here, the description of the transport mechanism that transports the recording medium M is omitted.
[0015]
Thus, the ink ribbon R is pressed by the head 11 against the surface of the recording medium M conveyed in the direction of arrow T in the figure, and the head 11 is driven to print information. At this time, the platen roller 12 facing the head 11 is also rotated in the same direction as the recording medium M. Here, as the printing method, hot-melt type printing or sublimation type printing is assumed.
[0016]
FIG. 2 is a plan view of the guide roller 5.
[0017]
On the outer peripheral surface of the guide roller 5, spiral grooves 5a and 5b (friction generating portions) which are opposite to each other are formed from substantially the center along the axial direction toward both ends. The guide roller 5 is formed of metal, natural rubber, silicone rubber, urethane rubber, fluorine rubber, or the like. In the present embodiment, the guide roller 5 is formed by coating a metal surface with urethane rubber.
[0018]
The depth of each groove 5a, 5b is preferably in the range of 1 [μm] to 1 [mm], and the pitch of the grooves 5a, 5b is preferably in the range of 1 [mm] to 100 [mm]. In the present embodiment, the depth of the groove is set to 30 [μm], and the pitch of the groove is set to 3 [mm].
[0019]
The inclination angle (A in the figure) of each of the grooves 5a and 5b may be larger than 0 [°] and smaller than 90 [°], but is preferably in the range of 20 [°] to 70 [°]. In the present embodiment, the inclination angle A of the grooves 5a, 5b is set to 45 [°].
[0020]
The guide roller 5 is arranged in the positional relationship shown in FIG. That is, since the guide roller 5 according to the present embodiment rotates along with the ink ribbon R according to the travel of the ink ribbon R, the spiral grooves 5a and 5b are formed along the axis of the guide roller 5 along the rotation direction of the roller. It is attached in such a direction as to go to both ends from the direction center.
[0021]
Thereby, the frictional force between the ink ribbon R traveling in the direction of the arrow T in the figure and the outer peripheral surface of the guide roller 5 causes the action of the grooves 5a and 5b to act on the ink ribbon R in the directions of the arrows Fa and Fb in the figure. And the ink ribbon R is spread in the width direction from the center to the outside. That is, when the ink ribbon R passes through the guide roller 5 which is rotatably provided, the stress from the grooves 5a and 5b acts outward from the center in the width direction, and the wrinkles and the slack are extended. Therefore, according to the ribbon cassette 1 of the present embodiment, it is possible to prevent a printing failure due to wrinkles or slack of the ink ribbon R.
[0022]
In the above-described embodiment, the case where the spiral grooves 5a and 5b are provided on the outer peripheral surfaces of the two guide rollers 5 and 5 on the upstream side and the downstream side of the head 11 has been described. The spiral grooves 5a and 5b may be formed on the outer peripheral surface of the guide roller 5, and the effect of the present invention can be obtained by using only one of them.
[0023]
Next, a printing apparatus 20 according to an embodiment of the present invention including the guide roller 5 having the above-described structure will be described with reference to FIG. Note that, among the components of the ribbon cassette 30 (hereinafter simply referred to as the cassette 30) incorporated in the printing apparatus 20, those components that function similarly to the above-described cassette 1 are denoted by the same reference numerals, and detailed description thereof will be given. Omitted.
[0024]
The printing apparatus 20 is a thermal printer head 21 (hereinafter, simply referred to as a head 21) for printing information by pressing an ink ribbon R against a surface of a recording medium M conveyed by a conveyance mechanism (not shown), and is opposed to the head 21. And a platen roller 22, two guide rollers 5, 5, and a cassette 30 that support the back side of the recording medium M to be conveyed. The head 21 is provided movably in the direction of arrow S in the figure.
[0025]
The cassette 30 has the same structure as the above-described cassette 1 except that the above-mentioned guide rollers 5 and 5 are replaced with two rollers 25 and 25 having no spiral friction generating portion on the outer peripheral surface. That is, the cassette 30 is set in the printing apparatus 20 such that the ink ribbon R extending between the two rollers 25, 25 is interposed between the head 21 and the platen roller 22.
[0026]
The two guide rollers 5, 5 provided separately from the cassette 30 on the printing apparatus 20 side can be retracted upward so as not to interfere with the mounting operation of the cassette 30. That is, during the mounting operation of the cassette 30, the cassette 30 is moved to the retracted position indicated by the broken line in the drawing. On the other hand, when it is arranged at the operation position indicated by the solid line in the drawing, it is configured to be pressed against the ink ribbon R.
[0027]
Also in the present embodiment, the two guide rollers 5, 5 are attached so as to follow the ink ribbon R so that the relationship described in FIG. In addition, the effect of the present invention can be achieved by providing only one of the rollers 5.
[0028]
As described above, also in the printing apparatus 20 of the present embodiment, similarly to the above-described embodiment, wrinkles and slack of the ink ribbon R can be prevented, and printing defects due to wrinkles and slack can be prevented. Further, since there is no need to provide the guide rollers 5 and 5 having spiral friction generating portions in the ribbon cassette 1 as in the above-described embodiment, the manufacturing cost of the cassette 30 can be reduced.
[0029]
It should be noted that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements in an implementation stage without departing from the spirit of the invention. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the above-described embodiment. Further, components of different embodiments may be appropriately combined.
[0030]
For example, in the printing apparatus 20 according to the above-described embodiment, the two guide rollers 5 and 5 are rotated around the ink ribbon R, but the guide rollers 5 and 5 are rotated by a driving unit such as a motor. Is also good. In this case, the guide rollers 5 may be rotated along the running direction of the ink ribbon R at a rotation speed slightly higher than the running speed of the ink ribbon R.
[0031]
In detail, as shown in FIG. 5, the two guide rollers 5, 5 are mounted in the opposite direction to FIG. 3, and are rotated in the same direction at a slightly higher speed than the ink ribbon R. In other words, the guide roller 5 is set so that the spiral grooves 5a and 5b are directed from both ends to the center in the rotation direction of the guide roller 5.
[0032]
That is, when the guide roller 5 is driven to rotate at a slightly higher rotation speed than the ink ribbon R, the frictional force generated between the surface of the guide roller 5 and the ink ribbon R is applied to the ink ribbon R by the action of the grooves 5a and 5b. It acts in the directions indicated by arrows Fa and Fb in the figure. Thus, the ink ribbon R is stretched in the width direction from the center to the outside.
[0033]
In addition, when the ink ribbon R is not running, for example, during the initialization operation of the printing apparatus 20, the guide roller 5 can be rotated as described above to extend the wrinkles and slack of the ink ribbon R. Naturally, even in this case, if at least one guide roller 5 is provided, the effects of the present invention can be obtained.
[0034]
Further, the guide roller 5 having the above-described structure may be applied to an intermediate transfer film on which ink layers of respective colors are superimposed from the ink ribbon, without being limited to the above-described ink ribbon R. In this case, since the intermediate transfer film needs to be rotated in both the forward and reverse directions, for example, the guide roller 5 is driven to rotate while the intermediate transfer film is running in the forward direction, and the intermediate transfer film runs in the reverse direction. In this state, the guide roller 5 is driven to rotate in the opposite direction (the same direction as the film).
[0035]
Further, in the above-described embodiment, the case where the spiral grooves 5a and 5b are provided on the outer peripheral surface of the guide roller 5 has been described. However, the present invention is not limited to this. For example, as shown in FIG. Alternatively, the spiral friction generating portions may be formed by forming spiral rough surface portions 51a and 51b on the mirror-like outer peripheral surface. The structure of the friction generating portion may be any structure as long as a frictional force can be applied to the ink ribbon R.
[0036]
【The invention's effect】
As described above, since the ribbon cassette and the printing apparatus of the present invention have the above-described configuration and operation, it is possible to prevent poor printing caused by wrinkles and slack of the ink ribbon.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a ribbon cassette according to an embodiment of the present invention.
FIG. 2 is a plan view showing a guide roller incorporated in the ribbon cassette of FIG. 1;
FIG. 3 is a view for explaining an attachment state of the guide roller of FIG. 2 to an ink ribbon.
FIG. 4 is a schematic view showing a printing apparatus according to the embodiment of the present invention.
FIG. 5 is a view for explaining a relationship with an ink ribbon when a guide roller incorporated in the printing apparatus in FIG. 4 is driven.
FIG. 6 is a plan view showing a guide roller according to another embodiment.
[Explanation of symbols]
1, 30 ... ribbon cassette, 2 ... case, 3 ... delivery shaft, 4 ... winding shaft, 5, 50 ... guide roller, 5a, 5b ... spiral groove, 11, 21 ... thermal printer head, 12, 22 ... Platen roller, 20 printing device, 25 roller, 51a, 51b rough surface portion, R ink ribbon.

Claims (9)

With a ribbon of ink ribbon,
First and second shafts which are rotatably provided by winding and stretching the ink ribbon from both ends thereof;
The ink ribbon running by the rotation of the first and second shafts is pressed against the ink ribbon and extends in a direction intersecting the running direction of the ink ribbon. A guide roller having helical friction generating portions opposite to each other toward both ends. The guide roller is provided rotatably with the ink ribbon,
2. The ribbon cassette according to claim 1, wherein the helical friction generating portion is formed so as to extend from a central portion in the axial direction to both ends of the shaft along a rotation direction of the guide roller. 3. The guide roller is provided on at least one of an upstream side and a downstream side along a running direction of the ink ribbon with respect to a head for printing information by pressing the ink ribbon against a recording medium. Item 3. The ribbon cassette according to item 1 or 2. With a ribbon of ink ribbon,
First and second shafts which are rotatably provided by winding and stretching the ink ribbon from both ends thereof;
A head for printing information by pressing the ink ribbon running between the first and second axes against a recording medium;
Spiral friction is generated by being pressed against the ink ribbon and extending in a direction intersecting the running direction of the ink ribbon, and on the outer peripheral surface thereof, from the substantially central portion in the rotational axis direction toward the opposite ends of the shaft. And a guide roller having a portion. The guide roller is provided rotatably with the ink ribbon,
The printing apparatus according to claim 4, wherein the spiral friction generating portion is formed so as to extend from a central portion in the axial direction to both ends of the shaft along a rotation direction of the guide roller. A drive unit that drives the guide roller to rotate in the same direction as the traveling direction of the ink ribbon,
The printing apparatus according to claim 4, wherein the spiral friction generating portion is formed so as to extend from both ends in the axial direction toward the center of the shaft along the rotation direction of the guide roller. 7. The printing apparatus according to claim 6, wherein the driving unit drives the guide roller to rotate at a rotation speed higher than a traveling speed of the ink ribbon. The guide roller is driven to rotate in the direction opposite to the direction in which the ink ribbon follows the ink ribbon when the ink ribbon travels in the first direction and the ink ribbon follows in the second direction. The printing device according to claim 4, wherein 9. The ink jet printer according to claim 4, wherein the guide roller is provided on at least one of an upstream side and a downstream side in the traveling direction of the ink ribbon with respect to the head. Printing device.

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