JPH05169690A - Thermal printer - Google Patents

Abstract

PURPOSE:To enhance a printing speed and perform printing on a large paper surface by a method wherein a thermal line head conducts printing while traveling at right angles to a paper feed direction, and printing can be made with a printing width equal to the width of the head through one travel of the line head. CONSTITUTION:In a printing action, after paper is set in position, a thermal line head 1 conducts printing while moving from left to right along a guide shaft 2. After the line head 1 conducts printing to the right end, a platen 4 is moved downward, and a feed roller 5 is rotated to feed the paper by the printing width of the line head 1. After the platen 4 is moved upward to a predetermined position and the line head 1 is retuned to the left end, the thermal line head 1 again conducts printing while moving from left to right. The action is repeated until printing is completed. In this case, printing may be conducted through both a forward head stroke and a return head stroke.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal printer for printing a large area such as A2 size and A1 size.

[0002]

2. Description of the Related Art Thermal heads include thermal line heads and thermal serial dot heads. Thermal line heads have a head width (direction perpendicular to the paper feed direction) of 1
Since each dot is printed continuously in the paper feeding direction, there is an advantage that the printing speed is fast, but in order to make the printing density uniform, the thermal line head should be placed between the thermal line head and the platen. It is necessary to make the pressure contact force the same across the entire head width, and if the head width becomes too long, there is a problem that the pressure contact force becomes uneven. In the conventional thermal line head, the maximum width is B4 (256 mm) or The size is A3 (297 mm). Therefore, there is a problem that printing cannot be performed on a recording paper having a width exceeding these. In the case of a thermal serial dot head, printing is performed with the head width (usually one line) while moving in the direction perpendicular to the paper feeding direction, so there is no limit to the printing width.
There was a problem that the printing speed was slow.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to enable printing with a width wider than the head width by using a thermal line head.

[0004]

In a thermal printer, a thermal line head is held so that its longitudinal direction coincides with the paper feeding direction, and the thermal line head is moved in a direction perpendicular to the paper feeding direction; A means for pressing and releasing the line head and the platen, a means for feeding the paper, and a width of the thermal line head is printed each time the thermal line head is moved once, and after printing, the thermal line head and the platen are removed. And means for controlling to feed the paper by the width of the thermal line head.

[0005]

[Function] By moving the thermal line head in the direction perpendicular to the paper feeding direction for printing, printing can be performed in a single movement with the width of the thermal line head in the vertical direction and the paper width in the horizontal direction. As a result, it becomes possible to print on A1 size paper in a short time. After printing, when the paper is fed in the width of the head, the head is detached from the platen. When printing, the head and the platen are brought into pressure contact with each other to prevent the paper from being distorted during feeding. As a mechanism for separating and pressing the head and platen, the platen was attached to a vertically movable mechanism.

[0006]

1 and 2 are perspective views showing an embodiment of the present invention. In this embodiment, the platen is a flat plate.
In FIG. 1, reference numeral 1 denotes a thermal line head, which is attached to a bearing 1A fitted in two guide shafts 2 orthogonal to the paper feeding direction and is attached to a bearing 1A. Be moved to. 4 is a platen,
As shown in FIG. 2, the guide shaft 2 is provided below the line head 1.
It is a smooth flat plate installed in parallel with the surface, the surface is covered with an elastic material, and a mechanism that can move up and down (not shown)
Installed on. FIG. 2 is a side view of the embodiment described above,
Is a feed roller for feeding the paper S. In the printing operation, after setting the paper at a predetermined position, printing is performed while moving the thermal line head 1 along the guide shaft 2 from left to right. After the line head 1 prints to the right end,
The platen 4 is lowered downward, the feed roller 5 is rotated, and the printing width of the line head 1 is fed. After raising the platen 4 to a predetermined position and returning the line head 1 to the left end, printing is performed while moving the line head 1 from left to right again. The above operation is repeated until the end. Printing may be performed on both the forward stroke and the return stroke of the head.

The present invention can also employ rollers as the platen. In the case of this embodiment, another guide shaft parallel to the guide line of the thermal line head is arranged below the paper passage, and the guide shaft holds the platen movably in the direction perpendicular to the paper feeding direction. By the timing belt, the thermal line head is always moved immediately below the thermal line head in synchronization with the thermal line head, and the pressing force to the thermal line head is released when the paper is fed.

[0008]

According to the present invention, printing is performed while moving the thermal line head in the direction perpendicular to the paper feeding direction, so that the head width can be printed by one movement of the line head. As a result, the printing speed has greatly improved, and printing on large paper surfaces has become possible.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is a side view of the above embodiment.

[Explanation of symbols]

 1 Thermal line head 1A Bearing 2 Guide shaft 3 Timing belt 4 Platen 5 Feed roller

Claims (3)

[Claims] 1. A means for transporting a thermal head installed in a direction whose longitudinal direction coincides with the paper feeding direction in a direction orthogonal to the paper feeding direction, a means for pressing and releasing the thermal head and the platen, and the above thermal head. While moving the printing head, printing is performed for the entire width of the thermal head, and the press contact of the platen with the thermal head is released at the end of each printing step of the thermal head, and the recording paper is conveyed by the width of the thermal head. A thermal printer characterized by having and. 2. The thermal printer according to claim 1, wherein the platen is a flat plate. 3. The thermal printer according to claim 1, wherein the platen is a roller and is moved together with the thermal head.