JPH08169633A - Paper jam detecting mechanism - Google Patents

Abstract

PURPOSE: To eliminate any effect of paper dust in using a magnetic sensor, and to unify it with the detection of whether there is paper or not as well as to simplify a job for assembly and adjustment in reducing the number of parts, in the paper jam detection of a line printer. CONSTITUTION: This paper jam detecting mechanism is equipped with a roller 6 embedded with a magnet 9 converting any motion of a continuous sheet 7 into a rotational motion, and a magnetic sensor 8 detecting any motion of the magnet 9 embedded in the roller 6, respectively. In addition, it is also equipped with a microswitch 11 detecting the presence of the continuous paper 7 installed unifiably with the roller 6 by a jam sensor holder 10, and a detecting part 14, comparing the output of the magnetic sensor 8 with a paper conveying quantity 17 of a tractor 2, outputting a paper jam signal 18, and further outputting a paper presence signal 19 from the output of the microswitch 11, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper jam detection mechanism, and more particularly to a paper jam detection mechanism for a printer device that uses continuous paper.

[0002]

2. Description of the Related Art Conventionally, a paper jam detecting mechanism of a printer of this type has a photo sensor 12 as shown in FIG. 5 as disclosed in, for example, Japanese Unexamined Patent Publication No. 4-266346.
Is used to directly check the passage timing of the paper hole. Further, the conventional paper presence / absence detection mechanism detects the presence / absence of a paper by projecting the feeler 13 on the continuous paper passage surface as shown in FIG. 6 and reading the movement of the feeler 13 with a photo sensor.

[0003]

Since the paper jam detecting mechanism of the conventional printer device directly detects the paper hole, paper dust adheres to the light emitting portion and the light receiving portion of the photo sensor, and the paper jam is erroneously detected. There is a problem. In addition, since the paper jam detection mechanism and the paper presence / absence detection mechanism are conventionally separate mechanisms, many components are required for assembly and adjustment, and the cost is high. Further, since the conventional paper presence detecting mechanism uses a feeler, it may be caught on a continuous paper when the continuous paper is conveyed, causing a paper jam to be damaged.

[0004]

A paper jam detection mechanism of the present invention includes a roller in which a magnet for converting the motion of continuous paper into a rotary motion is embedded, and a magnetic sensor for detecting the motion of the magnet embedded in the roller. And a detector for comparing the output of the magnetic sensor with the continuous paper transport amount of the continuous paper transport means and outputting a paper jam signal.

Further, the paper jam detecting mechanism of the present invention includes a micro switch integrated with the roller for detecting the presence or absence of the continuous paper, and a detecting section for outputting a paper presence signal from the output of the micro switch. Equipped with.

[0006]

Next, the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a dot line printer provided with an embodiment of the present invention, from a sheet insertion section to a tractor 2 through a printing mechanism section 1. FIG. 2 is a detailed view of the paper jam detection mechanism of this embodiment. Referring to FIGS. 1 and 2,
The paper jam detection mechanism of this embodiment includes a roller 6 in which a magnet 9 for converting the movement of the continuous paper 7 into a rotational movement is embedded.
The magnetic sensor 8 for detecting the movement of the magnet 9 embedded in the roller 6 and the jam sensor holder 10
The micro switch 11 that is integrated with the above and detects the presence of the continuous paper 7 is compared with the output of the magnetic sensor 8 and the paper transport amount 17 of the tractor 2 to output the paper jam signal 18, and the micro switch 11 The detection unit 14 outputs the paper presence signal 19 from the output.

Next, the paper jam detection operation of this embodiment will be described. The roller 6 is pressed against the rear paper guide 4 by a pressing spring 5. Therefore, the operation of the continuous paper 7 can be converted into the rotation operation of the roller 6. Further, since the magnetic sensor 8 and the roller 6 in which the magnet 9 is embedded are attached to the jam sensor holder 10, the positional relationship between the two is always constant, and the magnetic sensor 8 moves the magnet 9 regardless of the sheet thickness. Can be read. After the start of printing, when the continuous paper 7 makes a line feed operation of the outer peripheral length of the roller 6, if the magnetic sensor 8 does not detect the magnet 9 once, the detection unit 14 recognizes it as a paper jam and outputs a paper jam signal 18. Immediately stop the printer device and prevent the deterioration of paper jam.

Next, the paper presence / absence detection operation of this embodiment will be described. FIG. 3 is a state diagram with paper, and FIG. 4 is a state diagram without paper. As shown in FIG. 3, a fixed micro switch 11 is mounted on the tip of the jam sensor holder 10. Since the roller 6 retracts from the rear paper guide 4 by the thickness of the sheet when the sheet is inserted, the jam sensor holder 10 rotates about the rotation shaft 15, so that the tip 16 thereof floats up, leaves the micro switch 11, and the detection unit 14 detects the sheet. Detected as present. On the contrary, as shown in FIG. 4, when there is no sheet, the tip 16 of the jam sensor holder 10 keeps pressing the micro switch 11, so the detection unit 14 recognizes that there is no sheet.

[0009]

As described above, according to the present invention,
Since the movement of the continuous paper is converted into the rotation movement of the roller and the movement of the magnet embedded in the roller is detected by the magnetic sensor, it is not affected by the paper dust.

Further, since the paper jam detection mechanism and the paper presence / absence detection mechanism are integrated, the number of parts is small, the assembly and adjustment are simplified, and the cost is reduced. further,
Since the paper presence detection mechanism uses rollers, it does not cause paper jam or damage.

[Brief description of drawings]

FIG. 1 is a schematic view of a line printer provided with an embodiment of the present invention from a sheet insertion unit to a tractor.

FIG. 2 is a detailed view of this embodiment.

FIG. 3 is a schematic diagram in the case where the presence of paper is detected in this embodiment.

FIG. 4 is a schematic diagram in the case where the absence of paper is detected in this embodiment.

FIG. 5 is a perspective view of a conventional paper jam detection mechanism.

FIG. 6 is a perspective view of a conventional paper presence detection mechanism.

[Explanation of symbols]

 1 Printing Mechanism 2 Tractor 3 Front Paper Guide 4 Rear Paper Guide 5 Pressing Spring 6 Roller 7 Continuous Paper 8 Magnetic Sensor 9 Magnet 10 Jam Sensor Holder 11 Micro Switch 12 Photo Sensor 13 Feeler 14 Detector 15 Rotating Shaft 16 Tip 17 Paper Conveying Quantity 18 Paper jam signal 19 Paper presence signal

Claims (2)

[Claims] 1. A roller in which a magnet for converting the movement of a continuous paper into a rotational movement is embedded, a magnetic sensor for detecting the movement of a magnet embedded in the roller, an output of the magnetic sensor and a continuous paper conveying means. A paper jam detection mechanism comprising: a detection unit that outputs a paper jam signal by comparing the paper conveyance amount. 2. A micro switch that is integrated with the roller to detect the presence or absence of the continuous paper, and a detection unit that outputs a paper presence signal from the output of the micro switch. The paper jam detection mechanism described in 1.