JP4559804B2 - Thermal transfer printer head-up device - Google Patents

Description

The present invention relates to a head-up device for a thermal transfer printer, and more particularly to a head-up device for a thermal transfer printer that can lift up the thermal head when necessary and suppress the consumption of the thermal transfer ribbon as much as possible.

In conventional thermal transfer printers, printing is performed while sandwiching and transferring a print medium such as a label or tag and a thermal transfer ribbon between a thermal head and a platen roller. To reduce the consumption of the thermal transfer ribbon In addition, when the portion of the non-printing area on the printing medium reaches the printing unit, the thermal transfer ribbon is not transferred by separating the thermal head and the platen roller from each other.
For example, the structure is such that an electromagnetic solenoid is used as a drive source to raise the thermal head so as to be separated from the platen roller, and further, as in Patent Document 1, the head is raised by turning an eccentric cam provided below the thermal head. There is a structure, or a structure in which the platen roller is moved away from the thermal head as in Patent Document 2.

However, in the case of a head-up structure with an electromagnetic solenoid, there is a problem that a time loss until the head-up occurs due to a response time until the solenoid is attracted and a loss of mechanical efficiency between the link between the solenoid and the thermal head. There is. Due to this time loss, there is a problem that the ribbon consumption is increased as a result of winding the unused area of the ribbon accordingly.
Furthermore, when a solenoid is used, it is common to place the solenoid horizontally due to the structure of the printer, but it is necessary to convert the horizontal movement of the plunger into a vertical movement, which means that the operation efficiency is poor. There's a problem.
In addition, there is a problem that the operation sound of the plunger during operation of the solenoid is loud.
Furthermore, in the case of a head-up structure with an eccentric cam from the lower part of the thermal head, there is a problem that the structure becomes large and it is difficult to make the whole compact.
Note that the configuration in which the platen roller is separated from the thermal head has a problem that a rigid configuration is required because the reference portion (platen roller) for the printing operation is a movable structure.

JP-A-8-224933 JP 2002-86837 A

    The present invention has been considered in view of the above-described problems, and it is an object of the present invention to provide a head-up device for a thermal transfer printer capable of efficiently separating the thermal head from the platen roller and suppressing consumption of the thermal transfer ribbon. And

    It is another object of the present invention to provide a head-up device for a thermal transfer printer that can improve the head-up response speed in response to a signal that makes printing unnecessary.

    It is another object of the present invention to provide a head-up device for a thermal transfer printer that can be simply and miniaturized in structure.

In other words, the present invention focuses on moving the thermal head directly as much as possible by the driving force of the stepping motor, and simplifying the mechanism between the stepping motor that is the driving source and the thermal head that is the driven part as much as possible. A thermal transfer printer head-up device that has a thermal head and a platen roller, sandwiches and transfers a print medium and a thermal transfer ribbon between the thermal head and the platen roller, and prints on the print medium. A stepping motor that is positioned above the thermal head and whose output shaft is parallel to the head opening / closing shaft of the thermal head, and a gear that engages the output shaft on the left and right of the stepping motor; Link to the gear and link And pivotable linked to the closing direction and the opening direction of the thermal head about the shaft, via the link connected to the thermal head, the time the use of the thermal transfer ribbon printing on the print medium is not required Further, the thermal transfer printer head-up device is characterized in that the thermal head is pulled up slightly away from the platen roller by driving the stepping motor.

    The link may be connected to the head bracket of the thermal head at an end opposite to the link rotation shaft.

    The head bracket can urge the thermal head in the direction of the platen roller with a predetermined printing pressure, and can lift the thermal head when the link is swung in the opening direction of the thermal head. The head pressing member to be contacted can be in contact.

In the head-up device of the thermal transfer printer according to the present invention, the thermal head is moved directly as much as possible by a stepping motor having good operability or responsiveness. The stepping motor can respond quickly and can efficiently separate the thermal head from the platen roller, and the structure can be simplified to reduce the size and simplify the structure.

    In the present invention, since the thermal head is lifted up by the stepping motor, the head-up device of the thermal transfer printer with good response and compactness has been realized.

Next, a head-up device for a thermal transfer printer according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic perspective view of a thermal transfer printer 1 incorporating a head-up device 6 according to an embodiment of the present invention. The thermal transfer printer 1 spans a pair of left and right side frames 2 and both side frames 2. A thermal head 3 provided; a platen roller 4 provided in a cantilevered manner on one larger side frame 2 (right side in the figure) and opposed to the thermal head 3; a head opening / closing lever 5; 6.

The thermal head 3 is attached below the head bracket 7 and can be rotated around the head opening / closing shaft 8 in the opening / closing direction (a direction away from the platen roller 4 and a pressing direction) together with the head bracket 7.
With the thermal head 3 in an open state, a label, a tag or other belt-shaped print medium L and a belt-shaped thermal transfer ribbon R can be loaded between the thermal head 3 and the platen roller 4.
While the thermal head 3 is closed, the printing medium L and the thermal transfer ribbon R are sandwiched and transferred between the platen roller 4 and printing is enabled.

    The head opening / closing lever 5 opens and closes the thermal head 3 by rotating around a lever shaft 9 provided across the pair of left and right side frames 2 parallel to the transfer direction of the print medium L and the thermal transfer ribbon R. In this closed state, the pair of left and right head pressing members 10 can be pressed against the head bracket 7 (thermal head 3) with a predetermined pressing force.

FIG. 2 is a partially cutaway side view of the head pressing member 10. The head pressing member 10 includes a support portion 11, a press portion 12 that can be projected and retracted in the support portion 11, and the support portion 11 and the press portion 12. Coil spring 13 provided between the two.
The support portion 11 is fixed to the lever shaft 9 integrally, the lower end portion of the pressing portion 12 is brought into contact with the upper surface portion of the head bracket 7, and the pressing portion 12 can be brought into contact with the head bracket 7 with a predetermined pressing force by the coil spring 13. A predetermined printing pressure is generated between the thermal head 3 and the platen roller 4.
When the thermal head 3 is separated from the platen roller 4 by the operation of the head-up device 6, the coil spring 13 accumulates power, and the pressing portion 12 contacts the head bracket 7 while maintaining a predetermined pressing force. Thus, the necessary printing pressure can be applied when the thermal head 3 comes into contact with the platen roller 4 again.

    FIG. 3 is a perspective view of a main part of the head-up device 6 portion. The head-up device 6 includes a motor bracket 15 attached to a lower surface portion of a mounting plate 14 provided between the pair of left and right side frames 2, and A stepping motor 16, three left and right gears 18 engaged with the output shaft 17, a pair of left and right links 19 connected to the gear 18, and a pair of left and right links connecting the link 19 and the head bracket 7. And a plate 20.

The stepping motor 16 is positioned above the thermal head 3 (head bracket 7) by a mounting plate 14 and a motor bracket 15, and is fixedly attached thereto.
One end of the link 19 is fixed to the link rotation shaft 21 from the output shaft 17 of the stepping motor 16 via the gear 18, and the link 19 can swing up and down according to the forward and reverse rotation direction of the gear 18.
Therefore, if the output shaft 17 appearing on the right side in FIG. 3 rotates clockwise (solid line direction in the figure), the link 19 appearing on the right side swings clockwise (upward) around the link rotating shaft 21. The thermal head 3 can be lifted up from the platen roller 4 in the opening direction. Further, when the output shaft 17 rotates counterclockwise (dotted line direction in the figure), the link 19 swings counterclockwise (downward) around the link rotation shaft 21, and the thermal head 3 is moved to the platen roller. It is possible to press in four directions (closing direction).

    The link 19 has a long window 22 formed at the end opposite to the link rotation shaft 21, and a pair of left and right connecting pins 23 fixed to the connecting plate 20 facing the long window 22 are the long window 22. The swing of the link 19 can be transmitted to the head bracket 7 and the thermal head 3 via the connecting plate 20.

    An optional transfer mechanism (not shown) that allows the print medium L to be transferred even if the thermal head 3 is separated from the platen roller 4 by the head-up device 6 and the transfer of the thermal transfer ribbon R is temporarily stopped. Is provided upstream or downstream of the thermal head 3.

In the thermal transfer printer 1 having the head-up device 6 having such a configuration, the printing medium L and the thermal transfer ribbon R are sandwiched between the thermal head 3 and the platen roller 4 and the platen roller 4 is rotationally driven, whereby the printing medium L In addition, while transferring the thermal transfer ribbon R, information is printed on the print medium L with predetermined information.
When a control unit (not shown) outputs a signal notifying that the thermal transfer ribbon R has reached a non-printing area where it is not necessary, the stepping motor 16 of the head-up device 6 is driven to rotate, and its output shaft 17 is The head 3 is rotationally driven in the opening direction.

FIG. 4 is a schematic side view showing the relative relationship between the thermal head 3 and the platen roller 4 driven by the head-up device 6. The link 19 is connected to the link rotation shaft 21 from the output shaft 17 via the gear 18. The head bracket 7 is lifted upward via a connecting pin 23 facing the long window 22 and a connecting plate 20 to which the connecting pin 23 is attached, swinging upward (clockwise, solid arrow) The thermal head 3 is lifted up so as to be separated from the platen roller 4.
However, even in this open state, the pressing portion 12 of the head pressing member 10 enters the support portion 11 against the urging force of the coil spring 13, and the pressing portion 12 contacts the head bracket 7 while maintaining the pressing force. It touches.

    By re-driving the stepping motor 16 at the timing when the non-printing area passes along with the transfer of the printing medium L and the printing area reaches the positions of the thermal head 3 and the platen roller 4, The link 19 is swung downward (half and system direction, dotted arrow) around the link rotation shaft 21 to bring the thermal head 3 into contact with the platen roller 4 again, so that the head pressing member 10 has a predetermined printing pressure. Press to enable next printing.

Thus, by rotating the stepping motor 16 at a necessary timing, the link 19 is swung up and down around the link rotation shaft 21, and the thermal head 3 is separated and pressed against the platen roller 4. However, since the stepping motor 16 with good response is provided above the thermal head 3, the driving force of the stepping motor 16 can be transmitted directly to the thermal head 3 as much as possible, and the response is good. In addition, it is possible to lift up the thermal head 3 with a simple configuration.

1 is a schematic perspective view of a thermal transfer printer 1 incorporating a head-up device 6 according to an embodiment of the present invention. 3 is a partially cutaway side view of the head pressing member 10. FIG. It is a principal part perspective view of the head up apparatus 6 part same as the above. 3 is a schematic side view showing a relative relationship between the thermal head 3 and the platen roller 4 driven by the head-up device 6. FIG.

Explanation of symbols

1 Thermal transfer printer (Figure 1)
2 Pair of left and right side frames 3 Thermal head 4 Platen roller 5 Head opening / closing lever 6 Head-up device of thermal transfer printer 1 (Example, FIG. 3)
7 Head bracket 8 Head opening / closing axis 9 Lever shaft 10 Head pressing member (FIGS. 1 and 2)
DESCRIPTION OF SYMBOLS 11 Support part 12 Press part 13 Coil spring 14 Mounting plate 15 Motor bracket 16 Stepping motor 17 Output shaft 18 of the stepping motor 16 Gear 19 Link 20 Linking plate 21 Link rotating shaft 22 Long window 23 Linking pin L Tags)
R Thermal transfer ribbon

Claims (3)

It has a thermal head and a platen roller,
A print-up medium and a thermal transfer ribbon are sandwiched and transferred between the thermal head and the platen roller, and a head-up device for a thermal transfer printer for printing on the print-receiving medium,
A stepping motor is provided above the thermal head , and its output shaft is parallel to the head opening / closing axis of the thermal head, and
A gear that engages the output shaft on the left and right of the stepping motor;
A link coupled to the gear and swingable in a closing direction and an opening direction of the thermal head around a link rotation shaft;
Connected to the thermal head via the link,
When printing on the printing medium using the thermal transfer ribbon is unnecessary, the thermal head is pulled up slightly away from the platen roller by driving the stepping motor. Head-up device. The link, head-up apparatus of the thermal transfer printer according to claim 1, wherein said link pivot shaft, characterized in that linked to the head bracket of the thermal head at the opposite end. In the head bracket,
The thermal head can be urged in the direction of the platen roller with a predetermined printing pressure, and a head pressing member that can lift up the thermal head when the thermal head is swung in the opening direction by the link is applied. The thermal transfer printer head-up device according to claim 2 , wherein the head-up device is in contact with the thermal transfer printer.

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