JPH05270073A - Two-sheet thermal line printer - Google Patents

Abstract

PURPOSE:To prevent the release of one of sheet feed rollers from affecting the feeding of a sheet which is carried out by the other and print quality, by constituting the two sheet feed rollers in such a manner that the middle part between them can freely bend and by providing release means, which detach the corresponding sheet feed rollers from a thermal line head, at both ends of a roller shaft. CONSTITUTION:Printing is carried out on the receipt side and the journal side with a roller shaft 6 situated opposite a thermal line head 3 and with the roller shaft 6 inserted in two sheet feed rollers 7 and 8. The middle part between the sheet feed rollers 7 and 8 can freely bend, and release levers 10 and 11 for detaching sheet feed rollers 7 and 8, respectively, from the thermal line head 3 are provided at both ends of the roller shaft 6. Thus, even when one of the sheet rollers is released, it does not affect the feeding of a sheet and print quality which is carried out by the other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a roller shaft of a two-sheet thermal line printer used for POS or electronic cash registers.

[0002]

2. Description of the Related Art FIGS. 5 (A) and 5 (B) are diagrams showing a main part configuration of a conventional two-sheet thermal line printer. A conventional two-sheet thermal line printer includes a thermal line head 41, a roller shaft 42 provided to face the thermal line head 41, a receipt (R) side paper feed roller 43 and a journal penetrating the roller shaft 42. (J) side paper feed roller 44. When thermal paper is inserted and set between the R-side and J-side paper feed rollers 43 and 44 and the thermal line head, the thermal paper sandwiched between the paper feed rollers 43 and 44 and the thermal line head is When the feed roller rotates, it is fed in the direction of arrow A for printing.

When printing is not performed in the thermal line printer, if the thermal head, the thermal paper and the paper feed roller are left in contact with each other, the life of the thermal head is significantly reduced due to bias electrolytic corrosion. And the problem that the paper feed roller is deformed by the contact pressure occurs. For this reason, when the conventional 2-sheet thermal line printer does not print, as shown in FIG.
As shown in (A), the roller shaft 42 is released so that the paper feed rollers 43 and 44 do not come into contact with the thermal paper or the thermal line head 41.

[0004]

However, in the conventional two-sheet thermal line printer, if the J-side paper feed roller 44 is released when, for example, only the R side is desired to print, as shown in FIG. Side paper feed roller 43
Also becomes oblique to the thermal line head 41. Therefore, in the thermal paper on the R side, the released contact pressure on the J side is small and the contact pressure on the opposite side is large, so that there is a problem that stable paper feeding is not performed and print quality deteriorates.

An object of the present invention is, when printing is performed on only one of the R side and the J side, even if one of the paper feed rollers is in the release state, the other paper feed and print quality are impaired. The purpose is to provide a two-sheet thermal line printer that does not have the above.

[0006]

In the two-sheet thermal line printer of the present invention, the intermediate portion of two paper feed rollers is configured to be bendable, and each paper feed roller is attached to and detached from the thermal line head at both ends of the roller shaft. It is characterized in that a release means for controlling is provided.

[0007]

In the two-sheet thermal line printer of the present invention, the respective paper feed rollers are attached to and detached from the thermal line head by the release means provided at both ends of the roller shaft. At this time, if only one of the paper feed rollers is released, the middle portion of the two paper feed rollers bends, and the other paper feed roller remains in contact with the thermal line head.

[0008]

FIG. 1 is a schematic view showing the structure of the main part of a two-sheet thermal line printer which is an embodiment of the present invention.
The two-sheet thermal line printer 1 is arranged on an upper portion of a not-shown setting portion on which thermal paper is set, and is configured to discharge the thermal paper pulled out from below. A thermal line head 3 is provided above the thermal paper pull-out section 2, is supported by a support section 4, and is constantly urged toward a roller shaft 6 by a pressing spring 5. On the other hand, a roller shaft 6 provided so as to face the thermal line head 3 is provided with two paper feed rollers 7 and 8 for receipt and journal. The intermediate portion of the roller shaft 6 is configured to be bendable by a universal joint 9 (not shown), and release levers 10 and 11 (not shown) are provided at both ends of the roller shaft 6.

FIG. 2 shows a roller shaft 6 and a release lever 10.
It is the schematic which shows the structure of 11 and. The roller shaft 6 is
A not-shown universal joint 9 in the middle is supported by a holding spring 21, and is pulled by the holding spring 21 and constantly urged toward the thermal line head 3. At this time, when the release levers 10 and / or 11 are set to the release state, the end of the roller shaft 6 pulled by the release levers 10 and 11 is separated from the thermal line head 3.

FIG. 3 is a diagram showing the construction of the thermal line head 3, the roller shaft 6, and the paper feed rollers 7 and 8 when only one of the paper feed rollers is released. In this two-sheet thermal line printer, the universal joint 9 of the roller shaft 6 has the holding spring 2 (not shown) as described above.
The roller shaft 6 is urged toward the thermal line head 3 by being supported by 1 and pressed by the holding spring 31. Further, guide plates 32 are attached to the side surfaces of the paper feed rollers 7 and 8 which are adjacent to each other so as to appropriately maintain the distance at which the thermal paper abuts between the paper feed rollers and the thermal line head 3. At this time, when the release lever 11 (not shown) on the journal side is set to the release state, a part of the release lever 11 is pressed against the extended end portion of the thermal line head 3, and the end portion of the roller shaft 6 on the journal side is in contact with the thermal line head 3. Pulled in the opposite direction.
As a result, the universal joint 9 bends in the same direction and the paper feed roller 8 on the journal side is released.

FIG. 4 is a diagram showing the construction of the essential parts of a two-sheet thermal line printer which is another embodiment of the present invention. Even in this 2-sheet thermal line printer,
Similar to FIG. 3, when the release lever 11 on the journal side (not shown) is released, the end of the roller shaft 6 on the journal side is pulled in the direction opposite to the thermal line head 3, and the universal joint 9 bends in the same direction. The paper feed roller 8 on the journal side is released. However, in this two-sheet thermal line printer, the universal joint 9 of the roller shaft 6 is supported by the support portion 33, not the holding spring, and the roller shaft 6 and the thermal line head 3 always maintain an appropriate distance in contact with the thermal paper. Therefore, the guide plate 32 is unnecessary.

As described above, in the two-sheet thermal line printer of the present invention, when only one of the paper feed roller on the receipt side or the journal side is released, the intermediate portion of the roller shaft formed of the universal joint is bent. ..

[0013]

As described above, according to the present invention, even when only one of the paper feed rollers is released, the release can be surely made from the intermediate portion of the roller shaft, and the other paper feed rollers that are not released can also be released. Stable printing can be performed without being affected.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a main part configuration of a two-sheet thermal line printer that is an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a roller shaft and a release lever of the two-sheet thermal line printer.

FIG. 3 is a schematic diagram showing a configuration of a thermal line head, a roller shaft, and a paper feed roller of the two-sheet thermal line printer.

FIG. 4 is a diagram showing a main configuration of a two-sheet thermal line printer which is another embodiment of the present invention.

FIG. 5 is a schematic diagram showing a main part configuration of a conventional two-sheet thermal line printer.

FIG. 6 is a diagram showing a release state in a conventional two-sheet thermal line printer.

[Explanation of symbols]

 3 Thermal line head 6 Roller shaft 7 Paper feed roller 8 Paper feed roller 9 Universal joint 10 Release lever 11 Release lever

Claims (1)

[Claims] 1. A printing on a receipt side and a journal side, comprising a thermal line head, a roller shaft provided to face the thermal line head, and two paper feed rollers penetrating the roller shaft. In the two-sheet thermal line printer for performing the above, the intermediate portion of the two paper feed rollers is configured to be bendable,
A two-sheet thermal line printer characterized in that release means for attaching and detaching respective paper feed rollers to and from the thermal line head is provided at both ends of the roller shaft.