JP2004351847A - Ribbon rewinding device in ribbon feeding spindle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ribbon rewinding device in a ribbon feeding spindle whose ribbon rewinding rotational angle in a reverse transfer of a printing sheet is made larger, thereby enabling to make the reverse transfer (rewinding) of an ink ribbon longer than that of a conventional one. <P>SOLUTION: In addition to an attention given to an advantage of equipping two steps of stopper plates 24, 25 that rotate together with the ribbon feeding spindle 5, the device is equipped with a base 21 that forms two steps of stopper parts 43, 44 on its interior wall surfaces, a torque limiter 23, a first stopper plate 24 equipped with a spring side contact part 38 and a plate side contact part 39, a coil spring 26 that engages spring edge parts 26A, 26B in the spring side contact part 38 and the stopper part 43 of the base 21, and a second stopper plate 25 that can be engaged in the plate side contact part 39 of the first stopper plate 24 and in the stopper part 44 of the base 21, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a ribbon rewinding device for a ribbon supply shaft, and more particularly to a ribbon rewinding device for a ribbon supply shaft for an ink ribbon or another ribbon which is loaded into a thermal printer or the like and used for printing.
[0002]
[Prior art]
A conventional thermal transfer type thermal printer 1 will be outlined based on FIG.
FIG. 18 is a schematic side view of the thermal transfer type thermal printer 1. The thermal transfer type thermal printer 1 has an ink ribbon supply unit 2, a printing unit 3, and an ink ribbon winding unit 4.
[0003]
The ink ribbon supply unit 2 has a ribbon supply shaft 5, which holds a band-shaped ink ribbon R in a roll shape, and enables the ink ribbon R to be fed in a band shape. A ribbon rewinding mechanism 6 having a coil spring (not shown) and the like is provided.
[0004]
The printing unit 3 includes a thermal head 7 and a platen roller 8, and performs printing by transferring the printing paper P (continuous label) and the ink ribbon R together with the rotation of the platen roller 8. The printing paper P is obtained by temporarily attaching a plurality of label pieces L on the backing sheet S. After printing, only the backing sheet S is turned at the turning pins 9 and the label pieces L are peeled off. The peeled label piece L is detected by the label sensor 10.
[0005]
The ink ribbon take-up section 4 has a ribbon take-up shaft 11, and rotates the platen roller 8 and the platen roller 8 by the same drive motor 12 to take up the ink ribbon R.
[0006]
In the thermal transfer type thermal printer 1 having such a configuration, the platen roller 8 is driven to rotate in the forward direction during the printing operation in the printing unit 3, but the unprinted label piece L for performing the next printing is printed after the printing is completed. The platen roller 8 is conveyed in the reverse direction (back feed) in order to detect by (1).
When performing the reverse transfer, the ribbon supply shaft 5 is reversely rotated by the ribbon rewinding mechanism 6 so that the ink ribbon R in the ink ribbon supply unit 2 is not loosened, and the ink ribbon R can be rewound by a predetermined length. .
[0007]
However, the ribbon rewinding mechanism 6 causes the coil spring to accumulate with the rotation of the ribbon supply shaft 5 for feeding out the ink ribbon R in the forward direction, and the reaction force of the coil spring when the platen roller 8 rotates in the reverse direction. Since the ink ribbon R is rewound, there is a limit to the rewound length of the ink ribbon R using only the reaction force of the coil spring during the reverse transfer of the printing paper P, and the type of printing paper P or label There is a problem that the rewind amount is insufficient depending on the mounting position of the sensor 10 and the like.
[0008]
Further, the winding method of the ink ribbon R includes a front winding method in which the heat-sensitive transfer surface is exposed to the surface of the roll, and a back winding method in which the heat-sensitive transfer surface is positioned on the inner side of the roll. In the case where the forward and reverse rotation directions of 5 are opposite to each other, and one of the ink ribbons R is loaded in one thermal printer 1, it is necessary to provide a ribbon rewinding device that can handle each of them.
In addition, if the rewinding is performed by a single mechanism for both the front winding method and the back winding method, the rotation angle up to the maximum angle of 180 degrees, which is half of 360 degrees of the circumference of the ribbon supply shaft 5 for each method, is determined. There is a problem that only the rewind amount can be obtained and the rewind amount is insufficient.
[0009]
[Patent Document 1]
JP-A-9-52414
[0010]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a ribbon rewinding device in a ribbon supply shaft capable of performing reverse transfer (rewinding) of an ink ribbon over a desired length when printing paper is reversely transferred. The task is to provide.
[0011]
Another object of the present invention is to provide a ribbon rewinding device in a ribbon supply shaft which can make the rewinding length of the ink ribbon longer than that of a conventional one.
[0012]
Another object of the present invention is to provide a ribbon rewinding device for a ribbon supply shaft capable of increasing the forward and reverse rewind rotation angles of the ribbon supply shaft to 180 degrees or more during rewinding.
[0013]
Another object of the present invention is to provide a ribbon rewinding device in a ribbon supply shaft capable of coping with rotation in either the forward or reverse direction of the ribbon supply shaft, depending on how the ink ribbon roll is wound. I do.
[0014]
[Means for Solving the Problems]
That is, the present invention provides at least two stages of stopper plates that follow the rotation of the ribbon supply shaft, and causes the coil springs to accumulate energy by rotating the stopper plates to achieve a two-stage rotation angle to rewind the ink ribbon. The ribbon is wound around a ribbon in a roll shape, and the ribbon can be unwound in a belt shape, and the ribbon can be unwound by a predetermined length. A return device, wherein the base is attached to a bracket rotatably supporting the ribbon supply shaft, the ribbon supply shaft is inserted therethrough, and at least a two-stage stopper portion is formed in an axial direction of an inner wall surface of the base; Stopper plate provided with a spring-side contact portion and a plate-side contact portion protruding in the direction A coil spring that engages the spring end with the spring-side contact portion and one of the stopper portions of the base, and a coil spring that can be engaged with the plate-side contact portion of the first stopper plate; A second stopper plate engageable with the other stopper portion of the base.
[0015]
With the rotation of the first stopper plate and the second stopper plate, the coil spring can accumulate force in the ribbon rewinding direction.
[0016]
With the rotation of the ribbon supply shaft, the first stopper plate rotates by a first rotation angle, and its plate-side contact portion contacts the second stopper plate, further rotating the ribbon supply shaft. Accordingly, the second stopper plate can be rotated by the second rotation angle and can be engaged with the other stopper portion of the base.
[0017]
The second stopper plate includes a first stepped blade having a first circumferential angle engageable with the plate-side abutting portion of the first stopper plate; And a second stepped vane having a second circumferential angle that is axially offset and engageable with the other stopper of the base.
[0018]
The two-stage stopper portion of the base can be provided at the same angular position on the inner wall surface of the base.
[0019]
A cover that covers the base and rotatably supports the ribbon supply shaft, and a torque limiter attached to the ribbon supply shaft, wherein the torque limiter is located between the cover and the base; Can be attached to the ribbon supply shaft.
[0020]
A third stopper plate that engages with the second stopper plate to be rotatable and engages with the third stopper portion of the base can be provided.
[0021]
The rotation direction of the first stopper plate and the second stopper plate may be either forward or reverse.
[0022]
In the ribbon rewinding device for the ribbon supply shaft according to the present invention, at least two stages of stopper plates are provided to follow the rotation of the ribbon supply shaft, and the rotation of the stopper plate causes the coil spring to accumulate energy to rewind the ink ribbon. Is performed, the coil spring can accumulate at least the rotation angle corresponding to the overlapped rotation of the two-stage stopper plate, and the ink ribbon R due to the reaction force of the coil spring over a longer length. Can be secured.
Furthermore, since the stopper plate can be rotated in both forward and reverse directions, the ribbon supply shaft can be rotated in either direction when the printing paper is transported in reverse according to the ribbon winding method such as the front winding method or the reverse winding method. Even if it rotates, a predetermined rewind function can be exhibited.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a ribbon rewinding device 20 according to a first embodiment of the present invention will be described with reference to FIGS. However, the same parts as those in FIG. 18 are denoted by the same reference numerals, and detailed description thereof will be omitted.
1 is an axial sectional view of the ribbon rewinding device 20, and FIG. 2 is an exploded perspective view of the ribbon rewinding device 20. The ribbon rewinding device 20 includes a base 21, a cover 22, a torque limiter 23, It has a first stopper plate 24, a second stopper plate 25, and a coil spring 26.
[0024]
The base 21 is attached to a bracket 27. The ribbon supply shaft 5 is inserted into the bracket 27 and the base 21, and the ribbon supply shaft 5 is rotatably supported by a bearing 28 of the bracket 27.
The base 21 has a cylindrical shape opened on the side opposite to the ribbon supply shaft 5, and has two screw holes 29 for attaching a cover on the circumference thereof.
[0025]
The cover 22 has a bearing 30 capable of rotatably supporting the ribbon supply shaft 5, and accommodates a torque limiter 23, a first stopper plate 24, a second stopper plate 25, and a coil spring 26 therein and has a base. Along with covering 21, a fixing screw 32 is screwed into a fixing screw hole 31 at the end of the ribbon supply shaft 5, and a mounting screw 33 is screwed into a cover mounting screw hole 29 to be fixed.
[0026]
The torque limiter 23 is located between the cover 22 and the base 21, and is attached to the ribbon supply shaft 5 by a limiter screw 35 inserted into a limiter screw hole 34 of the ribbon supply shaft 5.
As described later, the torque limiter 23 supplies the ribbon with a predetermined torque (resistance) after the accumulated power of the coil spring 26 due to the rotation of the first stopper plate 24 and the second stopper plate 25 to the limit. The ink ribbon R can be fed from the shaft 5 to the printing unit 3 and the ink ribbon winding unit 4 (FIG. 18).
[0027]
FIG. 3 is a perspective view showing an assembled state of the torque limiter 23 and the first stopper plate 24 when viewed from the second stopper plate 25 side. FIG. 4 is an assembled view of the torque limiter 23 and the first stopper plate 24. FIG. 3 is a perspective view showing a state viewed from a cover 22 side.
As shown in the figure, the first stopper plate 24 engages the engaging projection 36 formed on the torque limiter 23 with the engaging through hole 37 (FIG. 2) of the first stopper plate 24 to connect both members. Secure them together. The ribbon supply shaft 5 is inserted into the central through hole of the engagement protrusion 36.
A longer spring-side contact portion 38 and a shorter plate-side contact portion 39 are provided on the outer peripheral side of the circumferential portion of the first stopper plate 24 so as to protrude from each other in the axial direction.
[0028]
FIG. 5 is a perspective view of the second stopper plate 25 viewed from the base 21 side. The second stopper plate 25 includes a central cylindrical portion 40 through which the ribbon supply shaft 5 is inserted, and a first stopper plate 24. The first stepped vane portion 41 on the side of the base 21 and the second stepped vane portion 42 on the base 21 side that is displaced in the axial direction of the ribbon supply shaft 5 from the first stepped vane portion 41.
The first stepped blade portion 41 is engageable with the plate-side contact portion 39 of the first stopper plate 24, has a fan shape, and has a first circumferential angle α1.
The second stepped blade portion 42 is axially displaced from the first stepped blade portion, is engageable with a second stopper portion 44 (FIG. 8) of the base 21 described later, and has a fan shape. And has a second circumferential angle α2.
[0029]
FIG. 6 is a perspective view showing the assembled state of the torque limiter 23, the first stopper plate 24, the second stopper plate 25, and the coil spring 26 when viewed from the base 21 side. FIG. 8 is a perspective view showing the assembled state of the stopper plate 24, the second stopper plate 25, and the coil spring 26 as viewed from the cover 22 side. FIG. 8 is a perspective view of the inside of the base 21 as viewed from the second stopper plate 25 side. FIG.
As shown in FIG. 8, the base 21 has a two-stage stopper portion at least at the same angular position in the axial direction of the inner wall surface. That is, a first stopper portion 43 (one stopper portion) is formed on the cover 22 side, and a pair of second stopper portions 44 (the other stopper portion) are formed on a deeper inner position, that is, on the bracket 27 side. ing.
As shown in FIGS. 6 and 7, the coil spring 26 engages the pair of spring ends 26A and 26B with the left and right side surfaces of the spring-side contact portion 38 of the first stopper plate 24. And also engages with the first stopper 43 of the base 21.
[0030]
FIG. 9 is a perspective view showing a state in which only the second stopper plate 25 is fitted to the base 21 when viewed from the cover 22 side. FIG. 10 is a perspective view showing the torque limiter 23, the first stopper plate 24, FIG. 9 is a perspective view showing a state where a second stopper plate 25 and a coil spring 26 are fitted.
As shown in the drawing, a pair of spring ends 26A and 26B of the coil spring 26 are also provided on the left and right side surfaces of the spring-side contact portion 38 of the first stopper plate 24 and the first stopper 43 of the base 21. With the rotation of the ribbon supply shaft 5 or the first stopper plate 24 in either the forward or reverse (clockwise or counterclockwise) direction, one of the spring end 26A and the spring end 26B is engaged. The other of the spring end 26A and the spring end 26B rotates and moves together with the spring-side contact portion 38 of the first stopper plate 24 while being engaged with the first stopper portion 43, and the coil spring 26 Accumulates in the rewinding direction of the ink ribbon R.
[0031]
The operation of the ribbon rewinding device 20 having such a configuration will be described with particular reference to FIGS.
According to the ribbon rewinding device 20, the ink ribbon R can be rewound to the ribbon supply shaft 5 by a predetermined length regardless of whether the ink ribbon R is of a so-called front winding system or a back winding system. .
For example, FIG. 11 is a perspective view showing a state in which the first stopper plate 24 has been rotated counterclockwise in the figure from the state of FIG. 6 when viewed from the base 21 side, and the coil spring 26 has one spring end. While the 26A remains engaged with the first stopper portion 43 of the base 21 (stopped as a fixed end), the rotation of the spring-side contact portion 38 of the first stopper plate 24 causes the spring-side contact. The other spring end 26B rotates as a movable end until the portion 38 comes into contact with the first stepped blade portion 41 of the second stopper plate 25, and stores the biasing force corresponding to the first rotation angle θ1. . At this time, the ink ribbon R has begun to be fed out from the ribbon supply shaft 5 in a belt shape.
[0032]
FIG. 12 is a perspective view showing the state where the first stopper plate 24 is further rotated counterclockwise in the figure from the state of FIG. 11 as viewed from the base 21 side, and FIG. It is a perspective view.
As shown in the drawing, while the spring-side contact portion 38 is in contact with the first stepped blade portion 41 of the second stopper plate 25, the spring-side contact portion 38 is further rotated by the second rotation angle θ2 to form the second stepped blade portion 42. Engages with the second stopper portion 44 of the base 21 to further accumulate the energy of the coil spring 26, and further rotation is restricted.
[0033]
Then, with the further rotation of the first stopper plate 24, the ribbon supply shaft 5 rotates while applying a resistance force by a predetermined torque by the torque limiter 23, and the ink ribbon R is formed into a belt shape on the printing unit 3 side. It will run out.
[0034]
Here, when printing on the printing paper P (label piece L) in the printing unit 3 is completed, and the platen roller 8 is rotated in the reverse direction and the back feed is performed, the storage power for the rotation angle (θ1 + θ2) is obtained. The ribbon supply shaft 5 rotates in the reverse direction by the urging force of the coil spring 26, and with this reverse rotation, the ink ribbon R is rewound by a predetermined length in the direction of the ribbon supply shaft 5 from the printing unit 3.
For example, in the illustrated example, the first stopper plate 24 rotates by about 90 degrees as the first rotation angle θ1 from the state of FIG. 6 to the state of FIG. 11, and further moves from the state of FIG. 11 to the state of FIG. Since the one stopper plate 24 rotates about 135 degrees as the second rotation angle θ2 together with the second stopper plate 25, it is possible to perform the energy storage corresponding to the rotation of 90 + 135 = 225 degrees.
In other words, the rotation of the first stopper plate 24 and the second stopper plate 25 causes the coil spring 26, which has accumulated in the rewinding direction of the ink ribbon R, to rewind the ink ribbon R. The ink ribbon R can be rewound longer than with the ribbon rewinding mechanism 6.
[0035]
Next, FIG. 14 is a perspective view showing a state in which the first stopper plate 24 is rotated clockwise in FIG. 6 from the state of FIG. 6 when viewed from the base 21 side, and the coil spring 26 has the other spring end. With the 26B still engaged with the first stopper portion 43 of the base 21 (stopped as a fixed end), the rotation of the spring-side contact portion 38 of the first stopper plate 24 causes the spring-side contact to occur. Until the portion 38 comes into contact with the first stepped blade portion 41 of the second stopper plate 25, the one spring end 27A rotates as a movable end and stores the urging force corresponding to the first rotation angle θ1. . At this time, the ink ribbon R has begun to be fed out from the ribbon supply shaft 5 in a belt shape.
[0036]
FIG. 15 is a perspective view showing the state where the first stopper plate 24 is further rotated clockwise in the figure from the state of FIG. 14 as viewed from the base 21 side, and FIG. 16 is a perspective view of the same as viewed from the cover 22 side. It is.
As shown in the drawing, while the spring-side contact portion 38 is in contact with the first stepped blade portion 41 of the second stopper plate 25, the spring-side contact portion 38 is further rotated by the second rotation angle θ2 to form the second stepped blade portion 42. Engages with the second stopper portion 44 of the base 21 to further accumulate the energy of the coil spring 26, and further rotation is restricted.
[0037]
Similar to the case where the first stopper plate 24 rotates counterclockwise as shown in FIGS. 11 to 13, the torque limiter 23 rotates the first stopper plate 24 further clockwise to thereby set a predetermined torque. The ribbon supply shaft 5 rotates while applying the resistance force of the ink ribbon R, and the ink ribbon R is fed to the printing unit 3 side in a belt shape.
Further, similarly, when printing on the printing paper P (label piece L) in the printing unit 3 is completed, and the platen roller 8 is rotated in the reverse direction and the back feed is performed, the accumulated power for the rotation angle (θ1 + θ2) is obtained. The ribbon supply shaft 5 is rotated in reverse by the urging force of the coil spring 26, and the ink ribbon R is rewound by a predetermined length in the direction of the ribbon supply shaft 5 from the printing unit 3 with the reverse rotation.
[0038]
In the present invention, by appropriately designing the first circumferential angle α1 of the first stepped blade portion 41 and the second circumferential angle α2 of the second stepped blade portion 42 in the second stopper plate 25, The above-described first rotation angle θ1 and second rotation angle θ2 can be obtained. In addition, the sum (θ1 + θ2) can be set to satisfy 180 degrees <θ1 + θ2 <360 degrees.
Further, the relative formation positions of the first stepped blade portion 41 and the second stepped blade portion 42 in the second stopper plate 25 are symmetrical with respect to the first stopper portion 43 and the second stopper portion 44 in the base 21. Alternatively, by appropriately designing the coil ribbon 26 asymmetrically, the coil spring 26 can be stored at different rotation angles depending on the front winding method or the reverse winding method of the ink ribbon R.
[0039]
In the ribbon rewinding device 20 according to the first embodiment of the present invention, the two-stage rotating structure of the first stopper plate 24 and the second stopper plate 25 is employed. Is increased to increase the degree of energy storage of the coil spring 26. However, in the present invention, the rotation angle region can be further increased by using a stopper plate having three or more stages.
For example, FIG. 17 is a cross-sectional view of a ribbon rewinding device 50 according to a second embodiment of the present invention. In the ribbon rewinding device 50, in addition to the first stopper plate 24 and the second stopper plate 25, FIG. Thus, a third stopper plate 51 is provided.
The third stopper plate 51 has a configuration similar to that of the second stopper plate 25, and for example, protrudes in the axial direction from the second stepped blade portion 42 or the second stepped blade portion 42 of the second stopper plate 25. It is possible to engage with the formed second plate-side contact portion 52 to be rotatable and to be able to engage with the third stopper portion 53 of the base 21.
[0040]
By employing the ribbon rewinding device 50 having such a configuration, the coil spring 26 accumulates a rotation angle corresponding to the sum of the rotation angles of the first stopper plate 24, the second stopper plate 25, and the third stopper plate 51. Therefore, the length of rewinding the ink ribbon R can be increased by the reaction force of the coil spring 26.
[0041]
【The invention's effect】
As described above, according to the present invention, at least two stages of the first stopper plate and the second stopper plate can be engaged with each other so that the rotation angles thereof can be added, so that the back feed amount of the ribbon can be increased. Can be increased, and the ribbon can be held at an appropriate tension regardless of the type of printing paper or the like.
[Brief description of the drawings]
FIG. 1 is an axial sectional view of a ribbon rewinding device 20 according to a first embodiment of the present invention.
FIG. 2 is an exploded perspective view of the same.
FIG. 3 is a perspective view showing an assembled state of the torque limiter 23 and the first stopper plate 24 when viewed from a second stopper plate 25 side.
FIG. 4 is a perspective view showing an assembled state of the torque limiter 23 and the first stopper plate 24 when viewed from a cover 22 side.
FIG. 5 is a perspective view of a second stopper plate 25 as viewed from the base 21 side.
FIG. 6 is a perspective view showing an assembled state of the torque limiter 23, the first stopper plate 24, the second stopper plate 25, and the coil spring 26 when viewed from the base 21 side.
FIG. 7 is a perspective view showing an assembled state of the torque limiter 23, the first stopper plate 24, the second stopper plate 25, and the coil spring 26 when viewed from the cover 22 side.
FIG. 8 is a perspective view of the inside of the base 21 as viewed from the second stopper plate 25 side.
FIG. 9 is a perspective view showing a state where only the second stopper plate 25 is fitted to the base 21 when viewed from the cover 22 side.
FIG. 10 is a perspective view showing a state in which a torque limiter 23, a first stopper plate 24, a second stopper plate 25, and a coil spring 26 are fitted into the base 21 when viewed from the cover 22 side.
11 is a perspective view showing a state in which the first stopper plate 24 has been rotated counterclockwise in the figure from the state of FIG. 6, as viewed from the base 21 side.
12 is a perspective view showing a state where the first stopper plate 24 is further rotated counterclockwise in the figure from the state of FIG. 11 as viewed from the base 21 side.
FIG. 13 is a perspective view of the same as viewed from the cover 22 side.
14 is a perspective view showing a state in which the first stopper plate 24 has been rotated clockwise in the figure from the state of FIG. 6, as viewed from the base 21 side.
FIG. 15 is a perspective view showing a state in which the first stopper plate 24 is further rotated clockwise in the figure from the state of FIG. 14 when viewed from the base 21 side.
FIG. 16 is a perspective view of the same as viewed from the cover 22 side.
FIG. 17 is a sectional view of a ribbon rewinding device 50 according to a second embodiment of the present invention.
FIG. 18 is a schematic side view of a conventional thermal transfer type thermal printer 1.
[Explanation of symbols]
1. Thermal transfer type thermal printer (Fig. 18)
2 Ink ribbon supply unit
3 Printing section
4 Ink ribbon winding section
5 Ribbon supply axis
6 Ribbon rewind mechanism
7 Thermal head
8 Platen roller
9 Turning pin
10 Label sensor
11 Ribbon winding shaft
12 Drive motor
20 Ribbon rewinding device (first embodiment, FIGS. 1 and 2)
21 Base
22 Cover
23 Torque limiter
24 First stopper plate
25 Second stopper plate
26 Coil spring
26A Spring end of coil spring 26
26B Spring end of coil spring 26
27 Bracket
28 Bearing
29 Cover mounting screw holes
30 Bearing
31 Screw holes for fixing
32 fixing screw
33 Mounting screw
34 limiter screw hole
35 limiter screw
36 Projection for engagement
37 Through hole for engagement
38 Spring-side contact portion of first stopper plate 24
39 Plate-side contact portion of first stopper plate 24
40 Central cylindrical portion of second stopper plate 25
41 first stepped blade portion of second stopper plate 25
42 second stepped blade portion of second stopper plate 25
43 1st stopper part of base 21 (one stopper part)
44 Second stopper part of base 21 (the other stopper part)
50 Ribbon Rewinding Device (Second Embodiment, FIG. 17)
51 Third stopper plate
52 Second plate-side contact portion of second stopper plate 25
53 Third Stopper of Base 21
R ink ribbon (ribbon)
P Printing paper (continuous label)
S mount
L label piece
α1 First circumferential angle of the first stepped blade portion 41 (FIG. 5)
α2 The second circumferential angle of the second stepped blade portion 42 (FIG. 5)
θ1 First rotation angle (FIGS. 11 and 14)
θ2 Second rotation angle (FIGS. 12 and 15)

Claims (7)

A ribbon rewinding device in a ribbon supply shaft that holds a ribbon in a roll shape, holds the ribbon in a roll shape, enables the ribbon to be unwound in a belt shape, and enables the ribbon to be rewound by a predetermined length.
A base attached to a bracket that rotatably supports the ribbon supply shaft, and through which the ribbon supply shaft is inserted, and at least a two-stage stopper portion formed in the axial direction of the inner wall surface,
A first stopper plate provided with a spring-side contact portion and a plate-side contact portion protruding in the axial direction;
A coil spring that engages the spring end with the spring-side contact portion and the stopper portion of one of the bases;
A second stopper plate that is engageable with the plate-side contact portion of the first stopper plate and is engageable with the other stopper portion of the base;
A ribbon rewinding device for a ribbon supply shaft, comprising: 2. The ribbon rewinding device according to claim 1, wherein the coil spring accumulates energy in the ribbon rewinding direction as the first stopper plate and the second stopper plate rotate. 3. apparatus. With the rotation of the ribbon supply shaft, the first stopper plate rotates by a first rotation angle, and its plate-side contact portion contacts the second stopper plate,
The ribbon according to claim 1, wherein the second stopper plate rotates by a second rotation angle with the further rotation of the ribbon supply shaft, and engages with the other stopper portion of the base. Ribbon rewinding device on the supply shaft. The second stopper plate includes:
A first stepped blade having a first circumferential angle engageable with the plate-side contact portion of the first stopper plate;
A second stepped blade having a second circumferential angle that is axially offset from the first stepped blade and is engageable with the other stopper of the base. The ribbon rewinding device in the ribbon supply shaft according to claim 1. The two-stage stopper portion of the base,
2. The ribbon rewinding device according to claim 1, wherein the inner wall surface of the base is provided at the same angular position. A cover that covers the base and is capable of rotatably supporting the ribbon supply shaft,
A torque limiter attached to the ribbon supply shaft,
Has,
2. The ribbon rewinding apparatus according to claim 1, wherein the torque limiter is located between the cover and the base and attached to the ribbon supply shaft. 2. The ribbon supply shaft according to claim 1, wherein a third stopper plate that engages with the second stopper plate to be rotatable and engages with a third stopper portion of the base is provided. 3. Ribbon rewinding device.

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