JP2000238946A - Sheet feeding device for printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the notice of lack of sheet from a printer side without using a notice mark by providing a winding thickness detecting means for detecting the winding thickness of the sheet on a support means so as to be opposite to the cut end surface of a roll paper. SOLUTION: A label printer is constituted so that a label paper 6 is delivered through a guide roller 3 from a sheet feeding device 2 having the label paper 6 rotatably supported by a shaft member 7 horizontally protruded from the upper part of a square pole-like strut member 8, and passed through a thermal head 4 and a platen roller 5 to perform the printing to a label piece L. At this time, an optical sensor 11 as winding thickness detecting means is buried in the stripper surface 9 of the strut member 8. When the printing is successively performed to the labels L, and the label paper 6 is consumed to reduce the winding thickness on a core B, the reflected light returned from the cut end of the roll opposed to the optical sensor 11 to the optical sensor 11 is reduced. Accordingly, an LED is made to emit light according to the output of the optical sensor 11 to notify the lack of sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding device for a printer, and more particularly to a paper feeding device suitable for use in a printer for printing on rolled paper such as tags, labels, receipts and facsimile paper. It relates to a supply device.

2. Description of the Related Art Generally, price tags are used in supermarkets, department stores, and the like.
2. Description of the Related Art A printer that prints receipts, slips, and the like uses roll paper wound around a cylindrical winding shaft as printing paper. With these rolls, when the end of the paper is approached, a paper-out notice mark printed in red etc. appears to inform the user that the paper is running out. Has become.

However, according to the above-mentioned prior art, there is no way to know that the paper is about to run out unless a roll paper with a paper-out notice mark is set in advance. However, in some cases, such as when used for a receipt or when it is desired to make a copy, paper with a notice mark is not preferable. Further, there is also a problem that the cost of the roll paper is increased by printing the notice mark. SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems of the related art, and an object of the present invention is to provide a paper supply apparatus for a printer that enables a printer to notify a roll paper out of paper without using a notice mark. It is in.

In order to solve the above-mentioned problems, the present invention employs a feature that the present invention employs a winding thickness detection method for detecting the winding thickness of a sheet on a shaft support means, which is opposed to the edge of the roll paper. The means have been provided. Here, the winding thickness detecting means includes:
It is preferable that the optical sensor be configured by an optical sensor that emits a light beam in parallel with the shaft support and detects reflected light. Further, it is preferable that the optical sensor has an adjusting mechanism capable of adjusting a distance from the shaft supporting means.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to FIGS. In FIG. 1, reference numeral 1 denotes a label printer provided with a paper supply device 2 of the present invention,
The label printer 1 generally comprises a guide roller 3, a thermal head 4, a platen roller 5, and the like, in addition to the paper supply device 2. Reference numeral 6 denotes a label paper as a roll paper set in the paper supply device 2, and the label paper 6 is wound around a cylindrical core B and has a surface coated with a release agent such as silicone. It consists of a continuous backing sheet S and a label piece L temporarily attached thereon at a predetermined interval. Then, the label paper 6 is pulled out from the leading end, is printed on each label piece L via the guide roller 3, the thermal head 4 and the platen roller 5, and is discharged from a discharge port of a printer (not shown). I have. Here, the paper supply device 2 will be described. Reference numeral 7 denotes a shaft member as a shaft supporting means which extends in the horizontal direction and rotatably supports the label paper 6, and reference numeral 8 denotes a prismatic column member which supports the shaft member 7. One end of the shaft member 7 is a column. It is joined to the middle part of the member 8 at right angles to form a substantially L-shape. Then, the roll of the label paper 6 is hooked in such a manner that the core B is inserted through the shaft member 7 and held rotatably. Further, the periphery of the joint portion of the support member 8 with the shaft member 7 forms a flat stopper surface 9. 1
Reference numeral 0 denotes a support member provided on the other end of the shaft member 7 so as to face the stopper surface 9 of the support member 8. The support member 10 and the stopper surface 9 allow the roll of the label paper 6 to move in the axial direction. Movement restricting means for restricting movement is configured. The roll of the label paper 6 is allowed to rotate only on the shaft member 7 by the stopper surface 9 and the support member 10, so that the label paper 6 straightly enters the thermal head 4 and the platen roller 5, and the roll edge is formed. The distance between the end face and the optical sensor 11 described later is kept constant. 1
Reference numeral 1 denotes an optical sensor as a winding thickness detecting means embedded in a stopper surface 9 of the support member 8, and the optical sensor 11 is a roll sensor when the label paper 6 is mounted on the shaft member 7 as shown in FIG. It is provided in parallel with the edge end face, and opposite to the position of the predetermined winding thickness of the winding core B, the mount S wound thereon, and the label L. Here, the optical sensor 11 is connected to a power source 12, a light emitting diode (LED) 13 as a warning means, etc. as shown in FIG. The light reflected by the end face and returned is detected. The present embodiment has the above-described configuration. When a label is printed by the label printer 1 and the label paper 6 is consumed, the thickness of the roll on the core B is reduced, and the fore end of the roll facing the optical sensor 11 is reduced. Optical sensor 11 from end face
Since the reflected light returning to the LED 13 decreases, the circuit of FIG.
The current flowing through the device increases to emit light, and the user can be alerted to running out of paper. In addition, the amount of remaining paper when the LED 13 emits light can be adjusted by inserting a semi-fixed resistor or the like into the circuit of FIG. Thus, according to the present embodiment, it is possible to issue a warning of running out of paper without using a printing paper having a mark as in the related art and without applying a mechanical load to the core B or the label paper 6. In particular, since the label paper 6 is held by being hooked on the shaft member 7 via the core B, paying attention to the change in the thickness of the core B without being largely influenced by the diameter of the core B. A warning can be issued. Next, another embodiment of the present invention will be described. In the following description, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof will be omitted. FIG. 5 shows a second embodiment. The feature of this embodiment is that an adjustment mechanism that can adjust the distance between the optical sensor and the support means while keeping the path of the light beam parallel to the support means is provided. is there. In the figure, reference numeral 14 denotes a feed screw mechanism as an adjustment mechanism provided to enable the optical sensor 11 to move on the support member 8.
The feed screw mechanism 14 includes a knob 15 and a screw 16 that rotates integrally with the knob 15. The rotation of the screw 16 causes the optical sensor 11 to face the front end side of the roll of the label paper 6 on the stopper surface 9. It approaches and separates from the shaft member 7 (moves up and down). As a result, the path of the light beam emitted from the optical sensor 11 and reflected on the end face of the roll and returning to the optical sensor 11 is kept parallel to the shaft member 7 and the distance to the shaft member 7 is adjusted. Although the present embodiment configured as described above has substantially the same operation and effect as the first embodiment, in particular, in the present embodiment, the feed screw mechanism 14 is provided so that the optical sensor 11 can be moved. The reference value for determining when the thickness of the label paper 6 is to be raised and for issuing an alarm can be greatly changed. In each of the above embodiments, the case where the light emitting diode is used as the warning means for running out of paper has been exemplified. However, the present invention is not limited to this, and a warning by a sound such as a buzzer may be used. Warning characters may be displayed on the display device.

As described above in detail, according to the present invention, when the roll paper is consumed, the winding thickness on the core decreases, and this is detected by the winding thickness detecting means, so that printing can be performed as in the prior art. It is possible to issue a warning of running out of paper without using a marked paper. If the winding thickness detecting means is constituted by an optical sensor, it is possible to issue a warning that the paper has run out without applying a mechanical load to the winding core or the roll paper. further,
If the optical sensor can be moved while keeping the path of the light parallel to the shaft supporting means, various effects can be achieved, such as a large change in the remaining amount of paper and the roll size at the time of warning of running out of paper.

[Brief description of the drawings]

FIG. 1 is an overall view showing a printer according to an embodiment of the present invention.

FIG. 2 is a perspective view of the paper supply device shown in FIG.

FIG. 3 is a sectional view taken in the direction of arrows III-III in FIG.

FIG. 4 is a wiring diagram of an optical sensor and an LED or the like of a warning unit.

FIG. 5 is a perspective view similar to FIG. 2, showing a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Label printer 2 Paper supply device 6 Label paper (roll paper) 7 Shaft member (supporting means) 9 Stopper surface (movement restricting means) 10 Support part (movement restricting means) 11 Optical sensor (winding thickness detecting means) 14 Feed screw Mechanism (adjustment mechanism)

Claims (3)

[Claims] 1. A paper supply device for a printer, comprising: a shaft supporting means for rotatably supporting rolled paper on which paper is wound; and a movement restricting means for restricting axial movement of the rolled paper. A paper feeder for a printer, comprising: a roll thickness detecting means for detecting the roll thickness of the paper on the shaft supporting means, which is opposed to the edge end of the roll paper. 2. The sheet supply device for a printer according to claim 1, wherein said winding thickness detecting means comprises an optical sensor which emits a light beam in parallel with the shaft supporting means and detects reflected light. 3. The paper supply device for a printer according to claim 2, wherein said optical sensor has an adjusting mechanism capable of adjusting a distance between said optical sensor and said shaft support means.