JP2000246685A - Cutter edge and roll paper cutting device or thermal printer using thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutter edge, a roll paper cutting device using the cutter edge, and a thermal printer mounted with the roll paper cutting device constituted to allow the cutter edge to cut roll paper in such a manner that the cut edge of a paper piece of the roll paper is straight even with the progress of wear of the cutter edge. SOLUTION: This roll paper cutting device is provided with a serrated cutter edge 1 for manually cutting roll paper (thermosensible paper) K delivered outside of the device. A tension member S becoming a cutting fulcrum of the roll paper to apply specified tension to the roll paper when the roll paper is pulled upward for cutting is provided on the lower side of the cutter edge 1. The cutter edge 1 is so formed that a cross-sectional center line I with the tip of the cutter edge 1 as an origin is on an involute curve in which the distance from a fulcrum S1 is constant while the fulcrum S1 is the contact point of the tension member S with the roll paper.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutter blade suitable for being mounted on a desktop electronic device such as a register or a small thermal printer mounted on various portable information devices and the like, and using the cutter blade. The present invention relates to a roll paper cutting device.

[0002]

2. Description of the Related Art For example, in a general small line thermal printer equipped with a line type thermal head mounted on a desk-top type electronic device such as a register, a roll-shaped thermal paper is often used as a recording paper. In these printers, a saw-shaped cutter blade may be provided in the vicinity of the roll paper delivery port so that the thermal paper can be sent out of the apparatus after printing and cut manually at an appropriate position.

[0003] Such a cutting device using a cutter blade is widely used in various devices because of its simple configuration and low cost.

[0004]

However, the above-mentioned cutter blade is often integrally formed of plastic together with the housing or lid member of the printer for safety and ease of molding. Therefore, even if a hard blade is used for the cutter blade, it is inevitable that the cutter blade will be worn over time according to the number of times the recording paper is repeatedly cut.

That is, as shown in FIG. 5A, when a right-handed person generally operates, the roll paper 200 is moved from the left side to the lower right side with respect to the cutter blade 100 as shown by an arrow f. , First, the left end of the roll paper 200 comes into contact with the left end side L of the cutter blade 100 to make a cut,
As the roll paper 200 is pulled, the cutter blade 100
As a result, the paper piece 201a is cut off as shown in FIG. 5B.

When the wear of the cutter blade 100 does not progress, the distance at which the roll paper 200 comes into contact with the cutter blade 100 is almost constant, so that the cut edge of the paper piece 201a is almost straight. However, the cutter blade 10
As the wear of 0 progresses, there arises a problem that the cut end of the cut piece of paper 201b is gradually inclined.

This is a phenomenon that occurs not only because the sharpness of the cutter blade 100 is reduced, but also because the distance at which the roll paper 200 contacts the cutter blade 100 is not constant. That is, as described above, the cutting operation of the roll paper 200 is performed by pulling the roll paper 200 from the left side to the right side and abutting against the cutter blade 100 by the right-handed person who usually occupies a large number. As shown in (c), the cutter blade 200 wears more easily on the left side L than on the right side R, and when the number of cuts of the roll paper 200 is accumulated to several thousands or tens of thousands, the cutter blade 100 becomes The slant from the left side to the right side compared to when it is new is abraded to the naked eye.

As the wear of the cutter blade 100 progresses, the distance from the cutting fulcrum of the roll paper 200 increases.
Since the left end, the middle end, and the right end of 00 change respectively, the cut end of the paper piece 201b becomes oblique. Referring now to FIG. 6, worn cutter blade 100a
The relationship between the cutting position and the change in the distance between the paper discharge port S2 and the blade edge is shown.

FIG. 6B is a cross-sectional view taken along the line BB at the position where the degree of wear on the left side L of the conventional worn cutter blade 100a is severe, and FIG. 6C is the position where the degree of wear at the intermediate position is medium. (D) shows a cross section taken along the line B′-B ′, and (d) shows a cross section taken along the line B ″ -B ″ at the position on the right R where the wear does not progress. The symbol K indicates the roll paper, and the symbol F ′ indicates the direction in which the roll paper K is pulled.

The distance from the cutting edge t3 to the paper outlet S2 at the position where the degree of wear is severe is L1, and the distance from the cutting edge t2 to the paper outlet S2 at the intermediate position is L2.
Assuming that the distance from the cutting edge t1 to the paper discharge port S2 at the position where the wear is not progressing is L3, since L1 <L2 <L3, the cutting position of the roll paper K gradually shifts, and as a result, FIG. As shown in FIG. 5C, there has been a problem that the cut edge of the paper piece 201b is oblique.

The present invention has been devised in order to solve the above-mentioned problems, and a cutter blade capable of cutting a roll paper sheet so that the cut edge is straight even if the wear of the cutter blade progresses. It is another object of the present invention to provide a roll paper cutting device using the cutter blade and a thermal printer equipped with the cutting device.

[0012]

In order to achieve the above-mentioned object, a cutter blade according to the present invention is a saw-shaped cutter blade for manually cutting recording paper for printing. A tension portion that serves as a cutting fulcrum and applies a predetermined tension to the roll paper is provided, and a center line of a cross section starting from the cutting edge is a fulcrum at a contact point between the tension portion and the recording paper, and a distance from the fulcrum is constant. It is configured to be on an involute curve.

According to this, even when the wear of the cutter blade progresses, the blade edge is located on the involute curve where the distance from the fulcrum is constant, and the contact point between the tension portion and the recording paper is adjusted. Since the distance between the cutting edge and the cutting edge is always constant, the cutting edge of the paper sheet obtained by cutting the recording paper can always be in a straight line state, and the cutting edge of the paper sheet becomes oblique as the wear of the cutter blade progresses as in the conventional case. The situation can be prevented.

Further, the roll paper cutting device according to the present invention comprises:
A roll paper cutting device having a saw-shaped cutter blade for manually cutting the roll paper sent out of the apparatus, wherein the roll paper is pulled upward for cutting below the cutter blade. At this time, a tension member that serves as a cutting fulcrum of the roll paper and applies a predetermined tension to the roll paper is provided, and the cutter blade is configured such that a center line of a cross section starting from the cutting edge of the cutter blade is formed by the tension member and the roll. It is formed so that the contact point with paper is a fulcrum and the distance from the fulcrum is on an involute curve where the distance is constant.

According to this, even when the wear of the cutter blade progresses, the blade edge is located on an involute curve in which the distance from the fulcrum is constant, and the contact point between the tension member and the roll paper is adjusted. Since the distance to the cutting edge is always constant, the cut edge of the paper cut from the roll paper can always be kept in a straight line, and the cut edge of the paper cut becomes oblique as the wear of the cutter blade progresses as in the past. The situation can be prevented.

[0016] More specifically, the cutter blade is
It is important to design the cutting edge so that it is positioned on the above-mentioned involute curve even when the wear progresses. Further, the cutter blade may be formed of a resin molded product, or the tension member and the cutter blade may be integrally formed. According to this, the number of components can be reduced, and the incorporation into the electronic device becomes easy.

Further, the roll paper cutting device can be mounted on a thermal printer. In this case, even if the cutter blade is worn for a long time, the roll-shaped recording paper such as thermal paper is cut straight. be able to.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing the principle of the roll paper cutting device according to the present invention. In the figure, reference numeral 1 is
4 is a cutter blade used in the roll paper cutting device according to the present invention.

In the initial state where the cutter blade 1 is not worn, a plurality of blades 1a having a cutting edge T1 as shown in the A ″ -A ″ section (FIG. 1D) of FIG. It is formed in a saw shape. In addition, the code K indicates roll paper, and the code F
Indicates the direction in which the roll paper K is manually pulled. Since the cutter blade 1 serves as a contact point (cutting fulcrum S1) between the tension member S for applying tension to the thermal paper K and the thermal paper K, the cutting edge T
When the distance to 1 is C (for example, 2 cm), the center line I of the outer line 300 and the inner line 301 of the cutter blade 1 is
The resin is molded and designed to be on an involute curve (extended line) with the distance C kept constant from the cutting fulcrum S1.

That is, the cutting edge T1 is the same as the cutting edge T shown in FIG.
2, even if worn like the cutting edge T3 in FIG. 1B, the cutting edges T1, T2, and T3 are always located near the center line I as an involute curve. , T3 is almost always C (eg, 2c
m). Therefore, according to the roll paper cutting apparatus according to the present embodiment using such a cutter blade 1, even if the cutter blade 1 is worn, when the thermal paper K or the like is cut, the cut end of the paper piece is cut as shown in FIG. As shown in FIG.

Referring now to FIGS. 1B to 1D,
Even when the cutter blade 1 is worn as shown in FIG. 1A, the cutting fulcrum S1 and the cutting edges T1 to T1 are independent of the cutting position.
The fact that the distance to T3 is kept constant will be described. FIG.
(B) is a cross section taken along the line AA in the position where the degree of wear is severe on the left side L of the worn cutter blade 1a, and (c) is a cross section taken along the line A'-A 'in the middle position where the degree of wear is medium. ,
(C) shows the cross section along the line A ″ -A ″ at the position on the right R where the wear does not progress.

The worn cutter blade 1a
When the right-handed person manually cuts the thermal paper K, first, the right-handed person comes into contact with the cutting edge T located on the left side of the cutter blade 1a to make a cut. At this time, since the cutting edge T3 is located near the center line I as an involute curve of the cutter blade 1, the distance from the cutting fulcrum S1 to the cutting edge T3 is C + α, which is approximate to C.

Subsequently, as the thermal paper K is pulled, the thermal paper K is sequentially cut from the left side L to the right side R by an intermediate portion of the cutter blade 1a. At this time, since the cutting edge T2 located at the intermediate portion is located near the center line I as the involute curve of the cutter blade 1, the distance from the cutting fulcrum S1 to the cutting edge T3 is C + α ′, which is approximate to C, Also,
Since the cutting edge T1 on the right side R of the cutter blade 1 on which the wear has not yet progressed is located on the center line I as the involute curve of the cutter blade 1, the distance from the cutting fulcrum S1 to the cutting edge T1 is C.

Thus, even if the wear of the cutter blade 1 progresses or the cutting position of the thermal paper K moves from the cutting edge T3 → T2 → T1, the distance from the cutting fulcrum S1 is almost almost C (for example, 2 cm). ), The cut edge of the paper piece cut by the cutter blade 1 can always be linear. Next, a specific example of the cutter blade of the roll paper cutting device according to the embodiment will be described with reference to FIG.

FIG. 2 is a schematic sectional view showing a configuration example of the cutter blade. In the present embodiment, a tension member S that applies tension to the thermal paper is formed integrally with the cutter blade 1. This reduces the number of components and facilitates incorporation into electronic devices such as printers. Note that polycarbonate or the like is used as a resin forming the cutter blade 1 and the tension member S.

As described above, the center line I of the outer line 300 and the inner line 301 of the cutter blade 1 has a constant distance from the contact point (cutting fulcrum) between the tension member S and the thermal paper (not shown). It is designed to be on the involute curve. Thereby, as explained in FIG. 1, even if the wear of the cutting edge T1 of the cutter blade 1 proceeds, the cutting edge T2,
T3 is located in the vicinity of the center line I, and the distance from the cutting fulcrum is kept substantially constant, so that the cut edge of the piece of paper cut by the cutter blade 1 can always be straight.

The configuration of the cutter blade is not limited to this, and various modifications are possible as long as the principle described with reference to FIG. 1 is followed. For example, the cutter blade 1 and the tension member S may be formed separately, the cutter blade 1 may be formed of a resin molded product, and the tension member S may be formed of a metal pin. Here, a configuration example of a thermal printer equipped with a roll paper cutting device having the cutter blade 1 will be described with reference to FIGS.

FIG. 3 is a perspective sectional view showing a schematic configuration of a thermal printer equipped with the roll paper cutting device according to the embodiment, and FIG. 4 is a side view (a) and a side sectional view showing a schematic configuration of the thermal printer. (B). Here, a configuration example of a small line thermal printer having a line type thermal head will be briefly described.

Referring to FIG. 4, a thermal printer P includes a platen roller 1 rotatably supported on a frame 101.
02, a head support 104 having a thermal head 103 pressed by the platen roller 102, a platen spring 105 for applying a biasing force to the platen roller 102 to the head support 104, and a platen spring 10
And a platen spring receiving plate 106 which receives a repulsive force of 5.

Further, when the recording paper K is exchanged or maintenance such as a paper jam due to paper jam or the like is performed, the head support 10 is used.
4 for separating the roller 4 from the platen roller 102
07a, and a head support 10 for engaging the cam 107a to separate the head support 104 from the surface of the platen roller 102.
4 is provided with a head-up pin 108, a support shaft 109 serving as a rotation center axis of the head support 104, and the like.

Then, the thermal paper K printed by passing through the platen roller 102 and the head support 104 is fed by the platen roller 102, and the recording paper feed port opened in the cover member 200 of the printer main body. 2
01 is sent out of the printer body. When a series of printing operations is completed, for example, the right-handed operator performs the cutting operation by holding the left side of the thermal paper K with the right hand and pulling the thermal paper K toward the cutting edge of the cutter blade 1.

Thus, for example, when cutting the thermal paper K when the cutter blade 1 is worn out due to long-term use, FIG.
The thermal paper K is first cut into contact with a sharply worn edge T3 based on the principle shown in (1), and is cut through a moderately worn edge T2 and a slightly advanced edge T1. At this time, the tension member S of the cutter blade 1 is
From the cutting fulcrum as the contact point of the thermal paper K with the cutting edges T1, T
Since the distance to 2, T3 is always kept constant, the cut edge of the cut piece of paper can always be straight.

The structure of the thermal printer P is as follows.
It merely shows a general configuration, and it goes without saying that the roll paper cutting device according to the present embodiment can be applied to printers of other configurations.

[0034]

As described above, the roll paper cutting apparatus according to the present invention is a saw-shaped cutter blade for manually cutting recording paper for printing, and serves as a fulcrum for cutting the recording paper. A tension portion for applying a predetermined tension to the paper is provided, and the center line of the cross section starting from the cutting edge is set at a contact point between the tension portion and the recording paper as a fulcrum, and on an involute curve where the distance from the fulcrum is constant. Even when the wear of the cutter blade progresses, the blade edge is located near an involute curve where the distance from the fulcrum becomes constant, and the tension portion and the recording paper The distance between the contact point and the blade edge is almost always constant, so that the cut edge of the paper sheet that cuts the recording paper can be made closer to a straight line even after the blade wears, or the blade edge can be involute By designing to be on the line, the distance between the contact point between the tension portion and the recording paper and the cutting edge is always constant, so that the cut edge of the piece of paper that cuts the recording paper can always be in a straight line state. As described above, it is possible to prevent a situation in which the cut edge of the paper piece is inclined with the progress of the wear of the cutter blade.

Further, the cutter blade may be formed of a resin molded product, or the tension member and the cutter blade may be formed integrally. According to this, the number of parts can be reduced, and there is an effect that the incorporation into the electronic device becomes easy. Further, the roll paper cutting device can be mounted on a thermal printer. In this case, even if the cutter blade is worn for a long time, the roll-shaped recording paper such as thermal paper can be cut straight. This has the effect.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing the principle of a roll paper cutting device according to the present invention.

FIG. 2 is a schematic sectional view showing a configuration example of a cutter blade of the roll paper cutting device according to the present invention.

FIG. 3 is a sectional perspective view showing a schematic configuration of a thermal printer equipped with the roll paper cutting device according to the present invention.

FIG. 4 is a side view and a side sectional view showing a schematic configuration of the thermal printer.

FIG. 5 is an explanatory diagram showing a cutting state of roll paper by a cutter blade.

FIG. 6 is an explanatory diagram showing a cut state of roll paper by a cutter blade of a conventional roll paper cutting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutter blade T1, T2, T3 Blade edge of cutter blade S Tension member S1 Cutting fulcrum I Center line of cutter blade 300 Outer line of cutter blade 301 Inner line of cutter blade K Thermal paper (roll paper)

Claims (6)

[Claims] 1. A saw-shaped cutter blade for manually cutting recording paper for printing, comprising: a tension portion serving as a fulcrum for cutting the recording paper and applying a predetermined tension to roll paper; A center line of a cross section of the cutter blade having a fulcrum at a contact point between the tension portion and the recording paper and having an involute curve having a constant distance from the fulcrum. 2. A roll paper cutting device provided with a saw-shaped cutter blade for manually cutting the roll paper sent out of the apparatus, wherein the roll paper is cut below the cutter blade for cutting. When pulled upward, a tension member that serves as a cutting fulcrum of the roll paper and applies a predetermined tension to the roll paper is provided, and the cutter blade has a center line of a cross section starting from a cutting edge of the cutter blade. A roll paper cutting apparatus, wherein a contact point between the tension member and the roll paper is used as a fulcrum, and the roll paper cutting apparatus is formed so as to be on an involute curve having a constant distance from the fulcrum. 3. The roll paper cutting apparatus according to claim 2, wherein the cutter blade is designed such that its cutting edge is positioned on the involute curve even when the wear is advanced. 4. The roll paper cutting device according to claim 2, wherein the cutter blade is formed of a resin molded product. 5. The tension member and the cutter blade,
The roll paper cutting device according to claim 4, wherein the roll paper cutting device is formed integrally. 6. A thermal printer comprising the roll paper cutting device according to claim 1 mounted thereon.