JPH063962U - Roll paper end detection mechanism in paper transport device - Google Patents

Abstract

(57) [Summary] [Purpose] To accurately detect the end of roll paper. [Structure] A core body 10 in which a roll paper 6 is wound around a holder 14 is rotatably supported. A lower guide 20 and an upper guide 22 are provided between the drive roller 30 and the holder 14.
And a roll paper 6 is formed.
It is pulled out from the roll unit 6 a, and is supplied to the image forming mechanism 16 via the paper transport path 28, the drive roller 30, and the pressure roller 32. The sheet conveying path 28 is arranged below the center of rotation of the core body 10, the upper guide 22 is configured to be vertically movable relative to the lower guide 20, and the upward swing of the upper guide 22 is detected by the sensor 44. To be detected. Roll paper 6
When the remaining amount of the roll paper 6 becomes zero, when the end of the roll paper 6 is fixed to the surface of the core body 10 or is fixed by the adhesive tape 12,
The sheet conveying force of the drive roller 30 and the pressure roller 32 raises the pull-out portion 6b of the roll paper 6 until it becomes perpendicular to the core body 10 and pushes up the upper guide 22. The rise of the upper guide 22 is detected by the sensor 44, and the sensor 44 outputs the end detection signal of the roll paper 6.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a roll paper end detection mechanism in a paper transport device.

[0002]

[Prior art]

 Conventionally, in a paper conveying apparatus using this type of roll paper, the detection of the end of the roll paper is performed by a roll of a detection arm 4 supported swingably about a rotation shaft 2 as shown in FIG. The rotation amount is converted into an electric signal and displayed on the display unit of the operation panel as the number of rolls 6a of the paper 6 decreases. As another method, as shown in FIG. 7, a paper detection sensor 8 is arranged above the conveyance path of the drawer portion 6b of the roll paper 6, and the sensor 8 detects the end of the roll paper 6. It was

[0003]

[Problems to be solved by the device]

 In the roll paper, the roll portion of the roll paper 6 is usually wound around the core body 10 made of a paper tube, and the end 6d of the roll paper 6 is entirely fixed to the core body 10 as shown in FIG. 8A. As shown in FIG. 8B, some are fixed by the adhesive tape 12, and some are not fixed as shown in FIG. 8C. When detecting the end of these roll papers, the method shown in Fig. 6 that detects the tilt of the detection arm has a defect that the end of the roll cannot be detected accurately. In the case of the method shown in FIG. 7, the end of the roll paper of the type shown in FIG. 8C can be detected, but the end of the roll paper of the type shown in FIG. 8A does not come off from the core. The sensor 8 cannot detect the end of the roll paper.

Further, in the roll paper of the type shown in FIG. 8B, when the roll paper runs out and tension is applied to the roll paper from the transport device, the end of the roll paper comes off the core body and is detected by the sensor. By the way, the adhesive tape attached to the end of the roll paper entered the drawing mechanism together with the roll paper, and there was a defect that caused a paper jam. In this case, the end of the roll paper may be cut before printing, but if the transport path is short, the cut will not be in time. The present invention aims to eliminate the above defects.

[0005]

[Means for solving problems]

 In order to achieve the above object, the present invention rotatably supports a roll paper 6 wound around a core body 10 in a holder 14, and a drawer portion 6b of the roll paper 6 is driven by a drive roller 30 and a pressure roller. In a sheet conveying device in which a nip pressure is arranged between the drive rollers 30 and the pull-out portion 6b is conveyed in a predetermined direction by the rotation of the drive roller 30, the core body 10 is inserted between the drive roller 30 and the holder 14. A sheet conveying path 28 composed of upper and lower guides 22 and 20 is provided below the center of rotation, and the upper guide 22 of the guides 22 and 20 faces the conveying path on the side facing the holder 14. A sensor 44 is provided that is swingably supported so as to swing upward from a horizontal state, and a sensor 44 that detects an upward movement of the upper guide 22 is provided.

[0006]

[Action]

 When the remaining amount of the roll paper 6 becomes zero and the end of the roll paper 6 is fixed to the core body 10, the pulling force of the drive roller 30 with respect to the pull-out portion 6b of the roll paper 6 causes the vicinity of the end of the roll paper 6. Becomes vertical to the core body 10, and the pull-out portion 6b of the roll paper 6 rises from the transport path 28. Due to this rise, the upper guide 22 is pushed up by the roll paper 6, and the guide 22 approaches the sensor 44. By this approach, the sensor 44 detects the upper guide 22, and the sensor 44 outputs a roll paper end detection signal.

[0007]

【Example】

 Hereinafter, the configuration of the present invention will be described in detail with reference to the embodiments shown in the accompanying drawings. Reference numeral 14 denotes a roll paper holder composed of a paper cassette arranged in front of the drawing mechanism 16, which is detachably supported by the cassette insertion portion of the machine body of the paper transport mechanism 18, and is attached to the core body 10 by the holder 14. The roll paper 6 around which the roll portion 6a is wound is rotatably supported. A lower guide 20 is arranged between the holder 14 and the drawing mechanism 16, and an upper guide 22 is arranged in parallel with the guide 20 at a predetermined interval.

An end portion of the upper guide 22 on the side of the drawing mechanism 16 is rotatably supported by an end portion of the lower guide 20 via a bracket 24. In the state in which the upper guide 22 is parallel to the lower guide 20, the counterclockwise swinging around the pivot 26 in FIG. 1 is locked by a stopper mechanism (not shown), Further, it is configured to be able to vibrate in the clockwise direction around the pivot 26.

An opposed space between the lower guide 20 and the upper guide 22 forms a conveyance path 28 for the pull-out section 6 b of the roll paper 6. A paper transport pinch roller mechanism including a drive roller 30 linked to a motor 29 and a pressure roller 32 is disposed near the end of the transport path 28. A paper detection sensor 34 is located above the transport path 28 and is attached to the machine body. The upper and lower guides 20 and 22 are provided with holes 36 located directly below the sensor 34 for detecting a sheet. Reference numeral 44 denotes a roll paper end detection sensor mounted on the machine above the movable portion of the upper guide 22, and detects the upper guide 22 when the upper guide 22 rises from the horizontal state by a predetermined amount. Then, the detection signal is output to the controller of the paper transport mechanism 18.

Reference numeral 38 denotes a remaining amount detecting arm, which is located above the holder 14 and is located slightly above the rotation center shaft 40 of the roll portion 6 a of the roll paper 6 in the direction in which the roll paper 6 is pulled out. Is rotatably supported by a shaft 42 about an axis parallel to the rotation center shaft 40. The arm 38 contacts the surface of the roll portion 6a of the roll paper 6, and the arm 38 is biased in the clockwise direction in FIG.

The rotation shaft 42 of the arm 38 is connected to an encoder (not shown) that converts the rotation amount of the arm 38 into an electric amount, and based on the output of the encoder, the controller rolls on the display unit of the operation panel. It is configured to display the remaining amount of the paper 6. The sensors 34 and 44 are connected to the controller of the paper transport mechanism 18.

The roll paper 6 supported by the holder 14 is pulled out in the direction of the image forming mechanism 16 and is supplied to the image forming mechanism 16 via the conveyance path 28 between the upper and lower guides 20 and 22 and the rollers 30 and 32. ing. The pull-out section 6b of the roll paper 6 is configured to be pressed between the rollers 30 and 32 and to be conveyed rightward in FIG. 1 by the clockwise rotation of the drive roller 30.

In the above structure, the arm 38 rotates clockwise in FIG. 1 following the decrease of the roll portion 6a of the roll paper 6. When the remaining amount of the roll paper 6 becomes zero, when the end of the roll paper 6 is fixed to the surface of the core body 10 or when the end of the roll paper 6 is fixed to the core body 10 by an adhesive tape. The pull-out force of the pinch roller mechanism causes the pull-out portion 6b of the roll paper 6 to be perpendicular to the core body 10 as shown by the dotted line in FIG. 1, and the pull-out portion 66 pushes up the upper guide 22. As a result, the upper guide 22 contacts the sensor 44 or approaches the sensor 44, and the sensor 44 detects the rise of the upper guide 44, that is, the end of the roll paper 6.

When the pull-out portion 6b of the roll paper 6 is in a state of being perpendicular to the core body 10 as shown by the dotted line in FIG. 1, the pulling force of the pull-out portion 6b serves as rotation torque with respect to the core body 10. The core body 10 stops operating, and the drive roller 30 idles with respect to the pull-out portion 6b of the roll paper 6 as well. When the end detection sensor 44 detects the upper guide 22, the controller stops driving the drive roller 30 and informs the buzzer or the display that the end of the roll paper has been detected.

Further, the controller drives a known cutter mechanism (not shown) to cut the roll paper 6. When the end of the roll paper 6 is not fixed or stopped on the core body 10, the part near the end of the roll paper is not perpendicular to the core body 10 but is separated from the core body 10. The end of the roll paper 6 in this case is detected by the sensor 34.

As the end detection sensor 44, various sensors other than the light reflection type photo sensor can be used. FIG. 4 shows an embodiment of the end detection sensor 44 using a limit switch. FIG. 5 shows an embodiment of the end detection sensor 44 using a light transmissive photosensor including a swing lever 46, a light emitting portion, and a light receiving portion.

In this embodiment, the swing lever 46 is rotatably supported on the sensor body by the pin 52, and the swing of the upper portion of the lever 46 blocks or interrupts the optical path between the light emitting portion and the light receiving portion. The paper is detected by swinging the lever.

[0018]

【effect】

 Since the present invention is configured as described above, there is an effect that the end of the roll paper can be accurately detected with a simple configuration.

[Brief description of drawings]

FIG. 1 is an explanatory side view.

FIG. 2 is an explanatory exploded perspective view.

FIG. 3 is an explanatory diagram of an end detection sensor.

FIG. 4 is an explanatory view showing another embodiment of the end detection sensor.

FIG. 5 is an explanatory diagram showing another embodiment of the end detection sensor.

FIG. 6 is an explanatory diagram of a conventional technique.

FIG. 7 is an explanatory diagram of another conventional technique.

FIG. 8 is an explanatory diagram of roll paper.

[Explanation of symbols]

 2 rotation axis 4 detection arm 6 roll paper 8 paper detection sensor 10 core 12 adhesive tape 14 roll paper holder 16 drawing mechanism 18 paper transport mechanism 20 lower guide 22 upper guide 24 bracket 26 pivot 28 transport path 30 drive roller 32 pressure Roller 34 Sensor 36 Hole 38 Remaining amount detection arm 40 Shaft 42 Shaft 44 Sensor 46 Swing lever 52 Pin 54 Sensor body

Claims (1)

[Scope of utility model registration request] 1. A roll paper (6) wound around a core body (10) is rotatably supported by a holder (14), and a drawer portion (6b) of the roll paper (6) is driven by a drive roller (3).
0) and the pressure roller (32) are arranged so as to be sandwiched, and the pull-out portion (6b) is conveyed in a predetermined direction by the rotation of the drive roller (30),
A paper transport path (28) which is located between the drive roller (30) and the holder (14) below the center of rotation of the core body (10) and which includes upper and lower guides (22) and (20).
Is provided, and the upper guide (22) of the guides (22) (20) can be swung so that its side facing the holder (14) swings upward from a state in which the guide (22) is horizontal to the transport path. And a sensor (44) for supporting the upper end of the upper guide (22) to detect the upward movement of the upper guide (22).