JPH0340614Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Application of the Invention) The present invention relates to a wrinkle absorbing device for a carbon ribbon in a thermal printer using a thermal transfer method.

(Prior art) In a thermal printer using a heat-sensitive transfer method, a tape-shaped label and a carbon ribbon are overlapped and heat-pressed between a platen roller and a thermal head, and a desired print is thermally transferred to the label. A push roller is placed adjacent to the platen roller and elastically pressed against the platen roller, and the push roller ensures stable printing and smooth running of the carbon ribbon.

However, conventionally, this type of push roller that is in elastic pressure contact with the platen roller has
That is, since both ends of the roller shaft are integrally supported, it swings parallel to the axial direction of the roller.

Therefore, especially in the width direction of the carbon ribbon,
When uneven printing or uneven printing is performed on the left and right sides, the carbon in the printed area is thermally transferred to the label side, but at this time, the base is generally shrunk by the heat of the thermal head, resulting in non-printing. Differences in the degree of expansion and contraction occur between the parts. This imbalance in the degree of stretch in the width direction is one of the causes of wrinkles. In this way, if the push roller is oscillated in parallel in the axial direction as in the conventional structure, it is not possible to absorb the error in the case of offset printing where the degree of expansion and contraction is different in the width direction of the carbon ribbon, resulting in unclear printing on the label. It has some defects.

(Purpose of the invention) In view of the above-mentioned conventional defects, the present invention provides a carbon ribbon wrinkle absorbing device using a thermal transfer method that can automatically absorb carbon ribbon wrinkles and always produce clear printing even when printing is offset. It is something to do.

(Summary of the invention) In order to achieve the above object, arms are provided at both axial ends of a carbon ribbon push roller, and a spring is provided on each arm so that both axial ends are independent from each other. It is configured to allow swinging and absorb wrinkles in the carbon ribbon.

(Example) The apparatus of the present invention is particularly effective for offset printing, and this offset printing will first be explained with reference to FIGS. 1 to 3.

In Figures 1 and 2, carbon ribbon 1
has a structure in which carbon 3 is layered on base 2,
Only one side of the width corresponds to the label size,
In addition, printing portions 4a, which are the transfer marks of barcodes arranged in a row at predetermined intervals in the longitudinal direction, are formed. The state in which the carbon 3 on only one side of the carbon ribbon 1 is peeled off to form the printable portion 4a is referred to as offset printing of the carbon ribbon 1. In addition, since there is no transfer mark in the longitudinal direction of the carbon ribbon 1 on the opposite side to the width direction, the non-printed part 4b
It is.

The tape-shaped label 5 shown in FIG. 3 is obtained by transferring the carbon 3 of the printing area 4a, which is the transfer trace of the carbon ribbon 1 of FIG. A label 7 of a certain size having an adhesive layer 8 on the back side is temporarily attached, and the carbon 3 is transferred onto the label 7 to form a barcode print 9.

Next, the apparatus of the present invention will be explained with reference to FIGS. 4 to 6.

Inside the printer 10, there are provided a thermal head 11 and a push roller 13 which are elastically biased by a platen roller 12 which is connected to a stepping motor (not shown) via a belt (not shown) and rotates intermittently. . The carbon ribbon 1 and the tape-shaped label 5 are superimposed between the thermal head 11 and the platen roller 12, and desired print is thermally transferred onto the label 5 side. Further, the push roller 13 elastically urges the carbon ribbon 1 and the label 5 against the platen roller 12 and transports these materials, and serves as a transport guide for the carbon ribbon 1.

The support structure of this push roller 13 is shown in detail in FIGS. 5 and 6, and its outline is such that a pair of arms 17a and 17b are fitted onto a pivot shaft 16 whose both ends are supported by a frame 14. A push roller 13 is attached to the tip of the arm, and a spring 20a is attached to the end of each arm.
and 20b are stretched so that they can swing independently at the ends of the push roller 13.

Specifically, the push roller 13 has a length equal to or longer than the width of the carbon ribbon 1 and the tape-shaped label 5, and has a shaft 15 fitted or fixed in the center thereof.
Both end shafts of the roller are connected to a pair of arms 17a and 1
7b so as to be rotatable. U-shaped support portions 18a and 18b are connected to the pair of arms 17a and 17b, and are attached to a pivot shaft 16 that serves as a pivot point. This pivot 16 has a central sleeve 21 between the supports 18a and 18b, and a frame 14 between the supports 18a and 18b.
End sleeves 22, 22 are loosely fitted between them.

Next, the ends of the pair of arms 17a and 17b,
Spring 20a and 20b are respectively attached to adjustment screws 19a and 19b screwed onto connecting frame 14a of frame 14, and push roller 13 attached to the tips of a pair of arms is pressed against platen roller 12. .

Next, returning to FIG. 4, the travel path of the carbon ribbon 1 and tape-shaped label 5 will be explained. The carbon ribbon 1 wound around the ribbon supply reel 30 is
It passes through the guide roller 31 and reaches the matching roller 32,
At this part, the tape-like label 5, which will be described later, is superimposed on the label, and the thermal head 11 and platen roller 12 thermally transfer the desired print onto the label side. The ribbon is separated from the label 5, passes through an eccentrically adjusted guide roller 33, guide rollers 34 and 35, and is wound up by a ribbon take-up reel 36 which is connected to a stepping motor via a belt and rotates intermittently.

The tape-shaped label 5 wound around the label supply reel 37 passes through the guide roller 38 and is then moved along the guide surface of the guide member 39 equipped with the movable sensor 40 and the label width adjusting member 41 to the matching roller 32.
, and is superimposed on the carbon ribbon 1,
Printing is performed on the label 7 portion between the thermal head 11 and the platen roller 12, and the temporarily attached label 7 is peeled off by the turning action of the mount 6 by the turning pin 42. For this label peeling, if a peeling auxiliary pin 43 is disposed facing the turning pin 42, the peeling action will be even better. Next, the mount 6 from which the label 7 has been peeled off is connected to the stepping motor via a belt via a guide roller 44, and the label (mount) take-up reel 4 is rotated intermittently.
It is wound up at 5.

In addition, if the tape-like label 5 with the printed label temporarily attached without peeling off the label 7 is to be used in another device, the guide roller 46 is arranged in front (downstream side) of the turning pin 42, and the turning pin Did not convert in part 42,
This is used as a mere guide pin, and the label (mounting paper) take-up reel 4 is passed through this guide roll 46.
5 is wound up and accommodated.

Next, to explain the operation of the present invention, as described above, in the case of offset printing in which printing is used only in the width direction of the carbon ribbon 1 as shown in FIG. 11, the base 2 shrinks due to heat, but the non-printing portion 4b hardly shrinks, so the length of the carbon ribbon in the longitudinal direction changes and wrinkles occur.

Therefore, this variation in the length of the carbon ribbon in the longitudinal direction is automatically absorbed by the push roller 13 of the device of the present invention.

For details, see Printing area 4 of carbon ribbon 1.
a and the non-printing portion 4b are arranged in a continuous row in the longitudinal direction, the printing portion 4a contracts as described above and the non-printing portion 4b does not contract. )
A larger tensile force acts from the other end (the side of the non-printing part of the carbon).

Thus, such a biased tensile force is absorbed by the push roller 13 of the device of the present invention. That is, only one end of this roller shaft is eccentrically swung. This eccentric oscillation means, for example, that the arm 17a at one end of the push roller 13 moves inward against the spring 20a, and the arm 17b at the other end moves inward against the spring 20a.
This is a movement that fluctuates outward against b. By twisting the push roller 13 in the axial direction in this way, it automatically adjusts the variation in the length of the carbon ribbon 1, which has different degrees of expansion and contraction in the width direction, thereby preventing the occurrence of wrinkles in advance and attaching the label to the label. It has clear printing.

(Effects) As described above, the present invention has a push roller rotatable at the tips of a pair of arms that can swing freely on a pivot, a spring is attached to the end of each arm, and both ends of the push roller in the axial direction are independent from each other. Since it is configured to swing and oscillate, it has the advantage of automatically absorbing wrinkles that occur in offset printing that is continuously printed on only one side of the carbon ribbon in the longitudinal direction, so that clear printing can always be made on the label.

Furthermore, since the springs provided at the ends of the pair of arms equipped with the push rollers are fixed by respective adjustment screws screwed onto the frame,
This spring pressure can be adjusted using an adjustment screw.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing offset printing on a carbon ribbon used to explain the carbon ribbon wrinkle absorbing device of the present invention, Fig. 2 is a cross-sectional view taken along the - line in Fig. 1, and Fig. 3 is a tape-shaped A perspective view of a label; FIG. 4 is a schematic diagram of a printer equipped with the device of the present invention;
FIG. 5 is a side view of the carbon ribbon wrinkle absorbing device in the thermal printer of the present invention, and FIG. 6 is a front view of the same. In the figure, 1... Carbon ribbon, 4a... Printing area, 4b... Non-printing area, 5... Tape-shaped label, 1
1...Thermal head, 12...Platen roller, 1
3... Push roller, 14... Frame, 16... Pivot, 17a, 17b... Arm, 19a, 19b...
Adjustment screw, 20a, 20b...spring.

Claims (1)

[Claims for Utility Model Registration] A pair of arms 7 that are fitted onto a pivot and can swing freely.
A push roller 13 made of carbon ribbon, which is opposite to the platen roller 1, is rotatably mounted on one end of a and 7b, and springs 20a and 20b are mounted on the other end of each of the arms, so that the push roller 13 is rotated in the axial direction. The springs 20a and 20b provided at the other ends of the pair of arms 7a and 7b are fixed by adjustment screws 19a and 19b screwed onto the frame 14, respectively. A wrinkle absorbing device for a carbon ribbon in a thermal printer, which comprises adjusting the pressing force of the push roller against the platen roller.