JP4464091B2 - Printer - Google Patents

Description

The present invention relates to a printer that performs printing using an ink ribbon, and more particularly to a printer that drives a platen roller that transports a continuous label body and a ribbon take-up shaft that winds up an ink ribbon by the same drive source.

6 is a schematic right side view illustrating the configuration of the conventional printer, FIG. 7 is a schematic front view illustrating the configuration of the conventional printer, and FIG. 8 is a schematic illustrating the configuration of the conventional printer. It is a left side view.
2. Description of the Related Art Conventionally, in a thermal transfer type printer that performs printing using an ink ribbon 1, referring to FIG. 6, a roll-shaped label obtained by winding a continuous label body 2 on which a label is temporarily attached to a belt-like mount at a predetermined interval. While the continuous body 2 is rotatably held by the supply unit 3, the roll-shaped ink ribbon 1 is rotatably held by the ribbon supply shaft 4, and the label continuous body 2 fed from the supply unit 3 and the ribbon supply shaft 4 are rotated. The drawn-out ink ribbon 1 is overlapped, and the label continuum 2 and the ink ribbon 1 are sandwiched by the platen roller 5 and the print head 6 and fed by the platen roller 5 (hereinafter referred to as forward transfer). Thus, printing is performed by thermally transferring the ink of the ink ribbon 1 to the label temporarily attached to the label continuum 2. The printed label is further transferred forward and discharged out of the apparatus, and the used ink ribbon 1 is wound around the ribbon winding shaft 7.

  In a state where the printed label is discharged out of the apparatus, the leading end of the next label is located downstream of the print head 6 in the label transfer direction, so that the label continuous body 2 is transferred in the reverse direction (back feed). After returning the leading end of the next label to the printing start position, printing is performed by moving forward.

  In such an apparatus that prints while repeating the forward transfer and the reverse transfer of the ink ribbon 1 and the label continuum 2, wrinkles may occur in the ink ribbon 1 when the transfer direction is switched. A technique for applying pretension to the ink ribbon 1 at the time of switching has been proposed (see, for example, Patent Document 1).

  However, in the prior art, since it is necessary to convey the ink ribbon 1 and the label continuous body 2 synchronously, a configuration in which the platen roller 5 and the ribbon take-up shaft 7 are rotationally driven by the same drive source may be employed. It is common. For example, as shown in FIGS. 7 and 8, a platen roller pulley 51 having a tooth shape is fitted to the platen roller 5 so that the platen roller 5 and the platen roller pulley 51 are integrally rotatable. At the same time, a ribbon take-up shaft pulley 71 having a tooth profile provided around the ribbon take-up shaft 7 is fitted, and the ribbon take-up shaft 7 and the ribbon take-up shaft pulley 71 are provided so as to be integrally rotatable. The first timing belt 82 is stretched between the drive gear 81 of the motor 8 and the platen roller pulley 51, and the second timing belt 83 is stretched between the platen roller pulley 51 and the ribbon take-up shaft pulley 71. As a result, the rotational force from the motor 8 is transmitted to the ribbon take-up shaft 7 via the platen roller 5. When printing is performed, that is, in the case of forward transfer, the first timing belt 82 and the second timing belt 83 are driven in the direction of arrow A shown in FIG. Is driven in the direction opposite to the arrow A shown in FIG. Further, the ribbon supply shaft 4 is provided with a back tension mechanism 41, and the ink ribbon 1 is conveyed while generating a constant back tension in the arrow B direction shown in FIG.

In such an apparatus, since the rotational driving force from the motor 8 is transmitted to the ribbon take-up shaft 7 via the platen roller 5, the ribbon take-up shaft 7 is started when the platen roller 5 is started. Slightly delayed compared to starting. Further, since the back tension is applied to the ink ribbon 1 by the ribbon supply shaft 4, the ink ribbon 1 is always in a tension state, and at the time of back feed, the follow-up of the ink ribbon 1 to the back feed of the label continuous body 2 is instantaneously delayed. Therefore, there is a problem that the label temporarily attached to the label continuous body 2 and the ink ribbon 1 are rubbed to cause printing stains.
Special table 2002-505215 gazette

  The present invention has been made in view of such problems, and the object of the present invention is to perform printing without causing rubbing between the label temporarily attached to the label continuous body and the ink ribbon during backfeed. The object is to provide a printer capable of preventing the occurrence of contamination.

In order to solve the above problems, the present invention has the following configuration.
Summary of the Invention in a first aspect, a print head for printing via the ink ribbon to the label continuum, and a platen roller for transporting the ink ribbon and the label strip by sandwiching said print head, fitted on A platen roller pulley that fits with a fitting portion that is an end of the platen roller and is fixed to the platen roller by a fastener, and a ribbon supply that supplies the ink ribbon to the print head and the platen roller A ribbon supply unit having a shaft, a ribbon winding unit having a ribbon winding shaft for winding the ink ribbon, a motor for driving the ribbon winding shaft and the platen roller, a pulley for the platen roller, and a motor for the motor. The first timing belt, which is stretched over the drive gear, the ribbon winding shaft, and the platen roller pulley. In a printer having a second timing belt and driving the platen roller and the ribbon take-up shaft by the same drive source, between the fitting portion of the platen roller and the fitting hole of the platen roller pulley. The ribbon take-up shaft has a rotation delay mechanism that starts rotation prior to the platen roller with respect to driving of the motor.
The gist of the invention described in claim 2 is characterized in that it has control means for carrying out extra conveyance control in advance for the amount that the platen roller is delayed from the start of rotation of the ribbon take-up shaft during printing on the continuous label body. To do.

  The printer of the present invention delays the rotation of the platen roller at the time of back feed, and instantaneously loosens the ink ribbon positioned between the ribbon take-up shaft and the platen roller. It is possible to follow the back feed of the label continuum without receiving the ink, and the label temporarily attached to the label continuum and the ink ribbon can be prevented from rubbing and the occurrence of printing stains can be prevented. There is an effect.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the same parts as those in the prior art are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 1 is an exploded perspective view showing a configuration of a platen roller and a pulley for a platen roller according to an embodiment of the printer according to the present invention. FIG. 2 is a diagram of the platen roller pulley shown in FIG. FIG. 3 is a cross-sectional view of the fitting portion formed in the platen roller shown in FIG. 1 and the fitting hole formed in the platen roller pulley. FIG. 4 is an explanatory diagram for explaining the state of the ink ribbon at the time of back feed of the embodiment of the printer according to the present invention, and FIG. 5 is another embodiment of the printer according to the present invention. It is a figure which shows the cross-sectional shape of the fitting part formed in the platen roller of this form, and the to-be-fitted hole formed in the pulley for platen rollers.

  In the present embodiment, a rotation delay mechanism is formed on the platen roller 5 so that the ribbon take-up shaft 7 starts earlier than the platen roller 5 during back feed.

  Referring to FIG. 1, a D-cut fitting portion 5 a is formed on the shaft of the platen roller 5, formed at the center of the platen roller pulley 51, and substantially the same shape as the cross-sectional shape of the fitting portion 5 a. The platen roller 5 and the platen roller pulley 51 are integrated by fitting the fitting portion 5a of the platen roller 5 into the fitting hole 51a and fixing the platen roller 5 with the fastener 52. Then, as shown in FIGS. 2 and 3, a gap is provided between the fitting portion 5a and the fitted hole 51a, and the gap acts as a rotation delay mechanism.

  Even if the platen roller pulley 51 starts to rotate by the motor 8 from the state shown in FIG. 3A, the platen roller pulley 51 has an angle θ (angle 2θ when the rotation in the forward direction and the reverse direction are combined). During the rotation, the rotation of the platen roller pulley 51 is not transmitted to the platen roller 5, and the rotation of the platen roller pulley 51 is not started until the state shown in FIG. Is transmitted to. Therefore, the distance that the conveyance of the ink ribbon 1 and the label continuum 2 at the start of rotation is delayed (hereinafter referred to as the rotational movement distance) is 2πr * (θ / 2π), where r is the platen radius, and the fitting is performed. By adjusting the size (angle θ) of the gap between the portion 5a and the fitted hole 51a, the rotational movement distance can be arbitrarily set.

  When the rotation direction of the platen roller 5 is switched, that is, at the time of back feed, even if the platen roller pulley 51 starts to rotate, the platen roller pulley 51 has an angle θ (when the rotation in the forward direction and the reverse direction are combined, the angle 2θ 4), the platen roller 5 does not rotate until the ribbon winding shaft 7 is rotated, and the ribbon winding shaft 7 starts to rotate, whereby the ink ribbon 1 is rewound from the ribbon winding shaft 7, and as shown in FIG. In addition, the ink ribbon 1 positioned between the ribbon take-up shaft 7 and the platen roller 5 is momentarily loosened.

  After the platen roller pulley 51 is rotated by an angle θ (angle 2θ when the rotation in the forward direction and the reverse direction are combined) from the start of rotation, the platen roller 5 also starts rotating, and the ink ribbon 1 and the label continuum 2 are Although the back feed is performed, the ink ribbon 1 positioned between the ribbon take-up shaft 7 and the platen roller 5 is in a slack state, so that the ink ribbon 1 is fed back to the label continuous body 2 without being loaded. Can follow.

  The ink ribbon 1 positioned between the platen roller 5 and the ribbon supply shaft 4 is back tensioned by the back tension mechanism 41 provided on the ribbon supply shaft 4, so that the platen roller 5 is stopped. In particular, the ink ribbon 1 is always stretched, and the ink ribbon 1 is not wrinkled during back-feeding.

  In this embodiment, as described above, when the rotation of the platen roller 5 is started, the conveyance of the ink ribbon 1 and the label continuum 2 is delayed by the rotational movement distance. It is preferable to start printing after absorbing the delay corresponding to the rotational movement distance by controlling to convey the ink.

  Furthermore, in the present embodiment, the gap between the fitting portion 5a and the fitted hole 51a is used as a rotation delay mechanism so as to delay the rotation of the platen roller 5. However, as shown in FIG. The rotation delay is caused by the fitting portion 5b D-cut so as to pass through the center and the fitting hole 51b in which two contact surfaces that are in surface contact with the D-cut surface of the fitting portion 5b are formed in a V shape. The mechanism may be configured, and as shown in FIG. 5 (b), the V-cut fitting portion 5c and the two contact surfaces in surface contact with the V-cut surface of the fitting portion 5c are V-shaped. A rotation delay mechanism may be configured by the fitted hole 51c formed in a shape. In this case, processing of the fitted hole 51b, the fitted part 5c, and the fitted hole 51c is complicated, but when the platen roller pulley 51 is rotated, the fitted parts 5b, c and the fitted hole 51b are used. , C are in contact with each other on the surface, so that durability is improved.

  Furthermore, in the present embodiment, the gap between the fitting portion 5a and the fitted hole 51a is used as a rotation delay mechanism so as to delay the rotation of the platen roller 5, but as shown in FIG. In addition, a rotation delay mechanism is constituted by a fitting portion 5d having a protrusion formed on the circumference and a to-be-fitted hole 51d in which a recess in which the protrusion of the fitting portion 5d is fitted with a margin is formed. You may do it.

  As described above, according to the present embodiment, at the time of back feed, the rotation of the platen roller 5 is delayed, and the ink ribbon 1 positioned between the ribbon take-up shaft 7 and the platen roller 5 is instantaneously loosened. In this state, the ink ribbon 1 can follow the back feed of the label continuous body 2 without receiving a load, and the label temporarily attached to the label continuous body 2 and the ink ribbon 1 are rubbed. There is an effect that it is possible to prevent the occurrence of print stains without occurring.

  Note that the present invention is not limited to the above-described embodiments, and it is obvious that the embodiments can be appropriately changed within the scope of the technical idea of the present invention. In addition, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, and can be set to a number, position, shape, and the like that are suitable for implementing the present invention. In each figure, the same numerals are given to the same component.

FIG. 3 is an exploded perspective view illustrating a configuration of a platen roller and a pulley for the platen roller according to the embodiment of the printer of the present invention. It is the figure which looked at the state by which the pulley for platen rollers shown in FIG. 1 was fitted to the platen roller from the pulley side for platen rollers. It is a figure which shows the cross-sectional shape of the fitting part formed in the platen roller shown in FIG. 1, and the to-be-fitted hole formed in the pulley for platen rollers. It is explanatory drawing for demonstrating the state of the ink ribbon at the time of the back feed of embodiment of the printer which concerns on this invention. It is a figure which shows the cross-sectional shape of the fitting part formed in the platen roller of other embodiment of the printer which concerns on this invention, and the to-be-fitted hole formed in the pulley for platen rollers. FIG. 10 is a schematic right side view illustrating the configuration of a conventional printer. It is the schematic front view explaining the structure of the conventional printer. FIG. 10 is a schematic left side view illustrating the configuration of a conventional printer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ink ribbon 2 Label continuous body 3 Supply part 4 Ribbon supply shaft 5 Platen roller 5a, b, c, d Fitting part 6 Print head 7 Ribbon take-up shaft 8 Motor 41 Back tension mechanism 51 Pulley 51a, b, Platen roller c, d Mating hole 52 Fastener 71 Ribbon take-up shaft pulley 81 Drive gear 82 First timing belt 83 Second timing belt

Claims (2)

A print head for printing via the ink ribbon to the label continuum,
A platen roller that sandwiches and conveys the label continuum and the ink ribbon with the print head;
A platen roller pulley that is fitted to a fitting portion whose fitting hole is an end of the platen roller and is fixed to the platen roller by a fastener;
A ribbon supply unit having a ribbon supply shaft for supplying the ink ribbon to the print head and the platen roller;
A ribbon take-up part having a ribbon take-up shaft for taking up the ink ribbon;
A motor for driving the ribbon take-up shaft and the platen roller;
A first timing belt stretched over the platen roller pulley and the drive gear of the motor;
A second timing belt spanned between the ribbon winding shaft and the platen roller pulley;
In the printer that drives the platen roller and the ribbon take-up shaft by the same drive source,
A rotation delay mechanism having a gap between a fitting portion of the platen roller and a fitting hole of the pulley for the platen roller, and causing the ribbon winding shaft to start rotating prior to the platen roller with respect to driving of the motor. A printer comprising:
The printer according to claim 1, further comprising a control unit that preliminarily conveys and controls a portion of the platen roller delayed from the start of rotation of the ribbon take-up shaft during printing on the label continuum.

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