JPH065970U - Ink ribbon drive mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] The number of optical sensors is reduced by detecting breakage of the ink ribbon with an optical sensor that detects the start and end of the ink ribbon. [Structure] Reflective walls 22a and 22b are provided on a bracket 21 for mounting an ink ribbon. The reflective wall 22a is provided so as to face the optical sensor 10a that detects the start end of the ink ribbon, and the reflective wall 22b is provided so as to face the optical sensor 10b that detects the end end of the ink ribbon. The ink ribbon is arranged between the reflective wall 22a and the optical sensor 10a and between the reflective wall 22b and the optical sensor 10b.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a mechanism for driving an ink ribbon, particularly a thermal transfer ink ribbon, and more particularly to a drive mechanism capable of detecting breakage of the ink ribbon.

[0002]

[Prior art]

 FIG. 5 is a plan view showing a conventional thermal transfer printer. In the figure, a ribbon cassette 1 accommodates a thermal transfer ink ribbon (hereinafter simply referred to as an ink ribbon) 2. A thermal head 3 is disposed between the ribbon cassette 1 and a portion of the ink ribbon 2 exposed from the ribbon cassette 1. A sheet 4 is wound around a platen 5 so as to face the ribbon cassette 1. The ribbon cassette 1 and the thermal head 3 move integrally along the shaft 6, and the thermal head 3 prints on the paper 4 during this movement.

FIG. 6 is a perspective view showing a conventional ink ribbon drive mechanism, and FIG. 7 is an exploded perspective view showing a ribbon cassette. In both figures, the ribbon cassette 1 comprises a ribbon cassette case 7 and a ribbon cassette cover 8. Holes 9a and 9b for detecting the start end and the end of the ink ribbon 2 are formed on both sides of the ribbon cassette case 7, and optical sensors 10a and 10b are arranged outside the holes 9a and 9b. Further, as shown in FIG. 6, an optical sensor 11 is also arranged above the ribbon cassette 1 for detecting breakage of the ink ribbon 2.

The ink ribbon 2 is wound around ribbon cores 12a and 12b, and the ribbon cores 12a and 12b are rotationally driven by winding shafts 13a and 13b, respectively. FIG. 8 is an explanatory diagram showing an ink ribbon. In the figure, reflective films 14a and 14b are attached to both ends of the ink ribbon 2, and the ends of the reflective films 14a and 14b are attached to the ribbon cores 12a and 12b, respectively. The optical sensors 10a and 10b shown in FIG. 6 detect these reflective films 14a and 14b as the start end or the end of the ink ribbon 2. Both the reflection films 14a and 14b are set to a length that prevents the optical sensors 10a and 10b from detecting them at the same time. When the ink ribbon 2 is broken, it is detected by a dedicated optical sensor 11 shown in FIG.

[0005]

[Problems to be solved by the device]

 However, in the conventional ink ribbon drive mechanism, a dedicated optical sensor is required to detect breakage of the ink ribbon, and the number of optical sensors increases when combined with the optical sensors that detect the start and end of the ink ribbon. There was a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce the number of sensors by making it possible to detect breakage of an ink ribbon by a sensor that detects the start end and the end of the ink ribbon. It is to provide a mechanism.

[0007]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, in a device having a first detecting means for detecting the start end of the ink ribbon and a second detecting means for detecting the end end of the ink ribbon, the means provided by the present invention is to sandwich the ink ribbon. A reaction member that reacts with the first and second detection means is provided on the opposite side of the first detection means and the second detection means, and the breakage of the ink ribbon is detected by the first and second detection means. That is what I did.

[0008]

[Action]

 In the present invention having the above configuration, since the reaction members corresponding to the first and second detecting means are provided respectively, when the ink ribbon is broken, the ink is detected by the first or second detecting means. The absence of the ribbon can be detected. Whether or not the detected absence of the ink ribbon is due to breakage of the ink ribbon or the start or end of the ink ribbon can be confirmed by driving the ink ribbon.

[0009]

【Example】

 Embodiments according to the present invention will be described below with reference to the drawings. Note that elements common to the drawings are given the same reference numerals. FIG. 1 is a perspective view showing an ink ribbon drive mechanism of an embodiment according to the present invention, and FIG. 2 is an exploded perspective view showing a ribbon cassette of the embodiment.

In both figures, the bracket 21 on which the ribbon cassette 1 is mounted has a thermal head 3 for printing on paper, take-up shafts 13a, 13b for driving the ribbon cores 12a, 12b, and start and end ends of the ink ribbon 2. Optical sensors 10a and 10b for detecting the are attached. The optical sensors 10a and 10b are reflection type sensors. The bracket 21 is also provided with reflecting walls 22a and 22b at positions facing the optical sensors 10a and 10b, respectively. The reflection walls 22a and 22b are made of a material that reflects the light emitted from the optical sensors 10a and 10b, respectively.

The ribbon cassette case 7 of the ribbon cassette 1 is formed with reflection wall holes 23a and 23b. When the ribbon cassette 1 is mounted on the bracket 21, the reflection walls 22a and 22b are formed in the reflection wall holes 23a and 23b. It is designed to enter each. When the ribbon cassette 1 is mounted on the bracket 21, the ink ribbon 2 is positioned between the reflection wall 22a and the optical sensor 10a and between the reflection wall 22b and the optical sensor 10b. The reflection films 14a and 14b (FIG. 8) are attached to the start end and the end of the ink ribbon 2 as in the conventional example.

Next, the ink ribbon breakage detection operation in this embodiment will be described with reference to the flowchart shown in FIG. Before starting printing, check the ink ribbon detection state of the optical sensors 10a and 10b. First, it is confirmed whether or not the optical sensor 10b is turned on (step 1). If the optical sensor 10b is turned on, it is judged that the ink ribbon 2 has been fed to the end, or the ink ribbon 2 is broken. In any case, it is determined that the ink ribbon 2 is absent. If is off, it is determined that the ink ribbon 2 exists at the position of the optical sensor 10b. This also applies to the optical sensor 10a.

When the optical sensor 10b is turned on and the optical sensor 10a is also turned on (step 2), the reflection film 14a or 14b is not detected by both the optical sensors 10a and 10b at the same time. It is judged to have broken (step 14). When the optical sensor 10b is off, the printing is ready, and therefore the printing start instruction is awaited (step 3). When there is an instruction to start printing, the winding shaft 13a is rotated counterclockwise in FIG. 1 (step 4) and printing is performed (step 5). When printing is completed, the rotation of the winding shaft 13a is stopped (step 6).

After the rotation of the winding shaft 13a is stopped, if both the optical sensors 10b and 10a are off (step 7, step 8), the printing for that time is completed, and the next instruction is awaited. When the optical sensor 10a is turned on in step 8, since the absence of the ink ribbon 2 is detected despite the fact that the ink ribbon 2 is wound around the winding shaft 13a, the ink ribbon 2 is broken ( Step 9). Further, when both the optical sensors 10b and 10a are both turned on (step 7, step 10), it is also broken (step 9). If only the optical sensor 10a is turned off in step 10, the winding shaft 13b is rotated clockwise in FIG. 1 (step 11), and the ink ribbon 2 is entirely wound around the winding shaft 13b.

When only the optical sensor 10b is turned on while the ink ribbon 2 is wound on the winding shaft 13b (steps 12 and 13), the ink ribbon 2 is broken (step 14). If both the optical sensors 10a and 10b are turned on (steps 12 and 15), the ink ribbon 2 is broken (step 14). When only the optical sensor 10a is turned on (steps 12 and 15), the winding shaft 13b is stopped (step 16) even if the winding is normally performed.

FIG. 4 shows a ribbon cassette according to another embodiment of the present invention. In the figure, in another embodiment, the ribbon cassette case 7 is provided with reflecting walls 22a and 22b, respectively. It goes without saying that even with this structure, the same effects as those of the above-described embodiment can be obtained.

[0017]

[Effect of device]

 As described in detail above, according to the present invention, the optical sensor for detecting the start end and the end of the ink ribbon is used to detect the breakage of the ink ribbon. Therefore, it is not necessary to provide an optical sensor dedicated to the breakage detection. .

[Brief description of drawings]

FIG. 1 is a perspective view showing an ink ribbon drive mechanism of an embodiment according to the present invention.

FIG. 2 is an exploded perspective view showing a ribbon cassette according to an embodiment.

FIG. 3 is a flowchart showing a fracture detection operation of the embodiment.

FIG. 4 is a perspective view showing a ribbon cassette of another embodiment.

FIG. 5 is a plan view showing a conventional thermal transfer printer.

FIG. 6 is a perspective view showing a conventional ink ribbon drive mechanism.

FIG. 7 is an exploded view showing a ribbon cassette.

FIG. 8 is an explanatory diagram showing an ink ribbon.

[Explanation of symbols]

 2 Ink ribbon 10a, 10b Optical sensor 13a, 13b Winding shaft

Claims (1)

[Scope of utility model registration request] 1. An ink ribbon that can be rotated in the forward and reverse directions and that winds up an ink ribbon.
In an ink ribbon drive mechanism having two winding shafts, a first detection means for detecting the start end of the ink ribbon, and a second detection means for detecting the end end of the ink ribbon, the first detection means sandwiching the ink ribbon. A member that reacts with the first and second detecting means is provided on the opposite side of the second detecting means, and the breakage of the ink ribbon is detected by the first and second detecting means. mechanism.