JPS61241175A - Label printer - Google Patents

Abstract

PURPOSE:To enable high printing quality to be maintained even on a label with a large printing width, by providing a rotatable back-up roller making parallel contact with a platen in the pressing direction of a thermal head. CONSTITUTION:With the platen 6 being rotated, a base paper 3 wound around a support shaft 4 is fed, and predetermined particulars are printed on the label 2 by the thermal head 10. The base paper 3 is taken up by a take-up shaft 9 while thereby maintaining a fixed tension, is separated from the label 2 by a releasing plate 7, and the printed label 2 is issued. Although the platen 6 tends to be elastically deformed by contact with the head 10, the back-up roller 11 backs up the platen 6, so that even an elongate platen 6 can be prevented from being deformed, and the pressed condition is maintained over the entire length of the platen 6 and the head 10. Accordingly, high printing quality can be maintained even on a label 2 with a large printing width.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a label printer that prints predetermined information on a label and issues the same.

BACKGROUND ART Conventionally, there is a label printer that guides a mount to which a label is attached along a fixed path, prints predetermined information on the label in the process, and then separates the printed label from the mount and issues it. As an example of a mechanism for printing predetermined information on a label, there is a mechanism in which a mount sheet with a label pasted thereon is placed between a platen that can rotate once and a thermal head that presses against the platen. With this type of configuration, the mount is conveyed by rotation of the platen.

Predetermined information is printed on the label using a thermal head.

Problems to be Solved by the Invention When the line length of the thermal head must be increased to accommodate wide labels, the platen to which the thermal head is pressed must also extend in the axial direction. It becomes a shape. However, when such a platen is used, the amount of deformation of the platen increases, making it impossible to maintain an even pressure contact state with the thermal head. Specifically, the pressure contact between the center portion of the platen and the thermal head tends to become weaker. This has the disadvantage that printing results become uneven and print quality deteriorates.

In order to solve the above-mentioned drawbacks, it has been considered to use a platen with a large diameter and less deformation. In this case, the distance from the printing start position to the position where the backing paper and label can be separated becomes long.

Since it becomes impossible to print for that length, it is not practical in reality.

The present invention was made in view of these points.

To obtain a label printer capable of maintaining high printing quality even for labels with a wide printing width.

Means for Solving the Problems The present invention includes a platen that can rotate once and a thermal head that presses against the platen via a mount with a label attached, and contacts the platen parallel to the platen in the press direction of the thermal head. A reinforcing roller that can rotate freely is installed.

As a result, the mount is conveyed by the rotation of the platen, and predetermined information is printed on the label by the thermal head. At this time, the reinforcing roller rotates as the platen rotates. This reinforcing roller.

Depending on its location, the thermal head comes into pressure contact with the platen and plays the role of reinforcing the platen against external forces applied to the platen. Here, even if a long platen is used, its deformation should be prevented, and a uniform pressure contact state between the platen and the thermal head should be maintained over the entire length. therefore,
High print quality should be maintained even on wide print width labels.

Embodiment of the Invention An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. A mount 3 to which a bell 2 is attached is held in a housing-like case 1 by winding one end of the mount 3 around a holding shaft 4. The other end of the mount 3 is placed closer to the platen 6 than the guide plate 5.
It is guided by a peeling plate 7 located near the second platen 6 at an acute angle, guided by two guide rollers 8, and wound and held around a winding shaft 9.

The platen 6 has a cylindrical shape that is rotated by a motor (not shown), and a thermal head 10 is in pressure contact with the platen 6 via the mount 3 and prints predetermined information on the label 2. It is provided. Further, a cylindrical reinforcing roller 11 that contacts the platen 6 is disposed in the pressing direction of the thermal head 10. This reinforcing roller 11 is rotatably held and arranged parallel to the platen 6.

In such a configuration, when the platen 6 is rotated, the mount 3 wound around the holding shaft 4 is conveyed.

Predetermined items are printed on the label 2 by the thermal head 10. Then, the mount 3 transported by the platen 6
is wound around a winding shaft 9 to maintain a constant tension, and separated from the label 2 at a peeling plate 7. At this point, a cover 2 with predetermined information printed thereon is issued.

On the other hand, as the platen 6 rotates, the reinforcing roller 11 rotates. This reinforcing roller 11 plays the role of preventing the platen 6 from changing its shape. In other words, the platen 6 tries to be elastically deformed by the pressure contact of the thermal head IO, but
The reinforcing roller 11 reinforces the platen 6 and prevents its deformation.

Here, even if a long platen 6 is used, its deformation is prevented, and the pressure contact state between the platen 6 and the thermal head IO is maintained over the entire length. Therefore, high print quality can be maintained even on the label 2 having a wide print width.

Effects of the Invention The present invention provides a rotatable ti+fi roller that contacts the platen parallel to the direction of the thermal head that presses against the platen, thereby preventing deformation of the platen due to the pressure contact of the thermal head. Even pressure is maintained over the entire length between the thermal head and, therefore, high printing quality is maintained even on labels with wide printing widths, and excellent adaptability is demonstrated for various types of labels with different printing widths. It has the effect of being able to obtain a device that does

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged side view of the vicinity of a platen showing an embodiment of the present invention, and FIG. 2 is a side view of the entire platen. 6...Platen, 10...Thermal head, 11.
・Reinforcement roller

Claims (1)

[Claims] A rotatable platen and a thermal head that presses against the platen through a mount with a label pasted are provided, and a rotatable reinforcing roller that contacts the platen in parallel with the thermal head is disposed in the press direction of the thermal head. A label printer featuring: