JP3477461B2 - Thermal line printer - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermal line printer.

[0002]

2. Description of the Related Art A thermal line printer which simultaneously provides a line of printing information requires a thermal line head having a length corresponding to the width of the paper, and it has been difficult to make it compact. In addition, when using cut paper such as thermal paper or peel-off paper without using an ink ribbon in a conventional thermal line printer, it is necessary to prepare a mechanism such as a separate roller or separation rubber when performing automatic paper feeding. However, there is a problem that the device becomes larger.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thermal line printer using a thermal line head and an ink ribbon, the printer having a simple structure and a small size.

[0004]

SUMMARY OF THE INVENTION A thermal line printer of the present invention is a casing having a substantially rectangular parallelepiped shape having upper and lower walls that are substantially parallel to each other and side walls that are substantially orthogonal to the upper and bottom walls; An insertion port and a discharge port for the printing paper, which are respectively formed on the one side wall and in a direction parallel to the ridge line formed by the upper wall and the side wall; A platen roller which is positioned in a casing corner space formed by the paper path and the ridge line and is rotatably supported with its rotation axis oriented in a direction parallel to the ridge line; A motor for rotating the platen roller and its drive gear train; and a paper path from the insertion port to the ejection port of the casing
Located on the opposite side of the platen roller and on the ridge of the casing
Can be elastically contacted with the platen roller by being biased toward the line
It is equipped with an effective thermal line head ; Specifically, at a position where the distance between each of the upper wall and the side wall forming the casing corner space and the roller surface of the platen roller is smaller than the radius size of the platen roller from the roller surface to the rotating shaft. A platen roller may be provided.

In the thermal line printer of the present invention, the thermal line head can swing about the swing axis, and is separated in the swing axis direction, and the bottom surface of the casing and the thermistor are separated.
It is preferable that the platen roller is biased by at least two V-shaped leaf springs that engage with the back surface of the ruline head .

At the bottom of the casing, a printer control board can be arranged avoiding the leaf spring and the thermal line head.

Further, in order to uniformly press the thermal line head against the platen roller and eliminate uneven printing, a swing axis of the thermal line head parallel to the rotation axis of the platen roller is attached to the platen roller side. It is desirable to movably support the spring in a direction that opposes the force of the leaf spring.

Further, when a plurality of cut sheets such as thermal paper and peel-off paper are superposed and supplied without using the ink ribbon, a special separating member has a separating function of feeding only the sheet on the platen roller side. Can be given as follows without using. That is, between the platen roller and the thermal line head, the first,
When the second sheet is supplied, a force F1 is applied to the first sheet that contacts the platen roller in the feeding direction by the platen roller, and a feeding direction is applied to the second sheet by friction with the first sheet. Is F2, a force acting between the paper and the head in the direction opposite to the feed direction is F3S, a force acting between the second paper and the casing in the direction opposite to the feed direction is FG, and The wedge effect force for preventing the paper from entering the gap between the first paper and the thermal line head is F3.
Let K3, F3S, F3K, and FG be the drag force acting on the second sheet in the opposite direction to the feed, and satisfy (1) F1> F3 '> F2 (2) F3K>F2> F3S + FG. If you do not need a special separating member,
Paper can be separated only by the platen roller and thermal line head.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to illustrated embodiments. Casing 50 shown in Figure 1, have no printing paper width (e.g. A4) than a width larger substantially rectangular parallelepiped, one another
Substantially parallel upper wall 50a and the bottom wall 50d, the upper wall 50a and the
Both side walls 50b, 50c, which are substantially orthogonal to the bottom wall 50d ,
And both end walls 50e and 50f. This rectangular parallelepiped
In the upper part of the casing 50 of the
b, and a pair of ridge lines sandwiched between the upper wall 50a and the side wall 50c
50g, but 50h is present, the inner cable of the ridge line 50g to be more formed and the one of the upper wall 50a and side walls 50b
In the single corner space, the rotation axis is approximately parallel to the ridge line 50g.
The platen roller 14 is rotatably supported with its 14a facing . As shown in FIG. 4, the platen roller 14
Forms a ridge line 50g with the roller surface 14b.
The distance between the upper wall 50a and the side wall 50b of the housing 50 is
Half of its own from the roller surface 14b to the center of the rotating shaft 14a
Casing to be smaller (closer) than the diameter size
Is provided close to the upper wall 50a and the side wall 50b of the 50.
There is. Below the platen roller 14, more specifically,
Connect the rotary shaft 14a of the ten roller 14 and the ridge line 50g.
The platen roller 14 is rotated at a lower position on the extension of the straight line.
A thermal line head 15 is arranged so as to be swingable around a swing shaft 15a that is substantially parallel to the rolling shaft 14 . As is well known, the thermal line head 15 includes the platen roller 14
It has a row of thermal heads aligned in the axial direction, and can print one row of character information at the same time. Between the thermal line head 15 and the bottom wall 50d of the casing 50, the thermal line head 15 is attached to the platen roller 1
A leaf spring 51 that urges toward 4 is provided. The pair of leaf springs 51 are provided so as to be separated from each other, and each of them is a fixed leg portion 51a on the bottom wall 50d and an elastic leg portion 51b that contacts the lower surface of the thermal line head 15.
And is formed in a substantially V shape. Elastic leg 51b
Comes into surface contact with the thermal line head 15 and brings it into close contact (elastic contact ) with the platen roller 14.

A sheet insertion port 52 corresponding to the width of the sheet is opened in the upper wall 50a of the casing 50, and a sheet discharge port 53 is opened in the side wall 50b. The sheet insertion port 52 and the sheet ejection port 53 are both formed along the platen roller 14 in the axial direction of the platen roller 14, and inside the sheet insertion port 52, the superposed sheet 20 and ink are stacked. A lower guide wall 52a for guiding the ribbon 33 between the platen roller 14 and the thermal line head 15 and an upper guide wall 52b are formed. A sensor 54 for detecting a sheet is arranged in an empty space formed by the platen roller 14 and the thermal line head 15. The paper detection sensor 54 can be composed of, for example, a reflection type photo interrupter.

End wall 50e and end wall 50f of casing 50
As shown in FIG. 2, a pair of support frames 55 and 56 for supporting the platen roller 14 and the thermal line head 15 are disposed inside each of the platen rollers 14. The drive motor 57 of is fixed. As shown in FIGS. 1 and 3, the output pinion 57a of the drive motor 57 meshes with a driven gear 14b provided on the shaft of the platen roller 14 via a gear train 58. The platen roller 14 is rotationally driven by a drive system including the drive motor 57 and the gear train 58,
The superposed paper 20 and ink ribbon 33 can be drawn between the platen roller 14 and the thermal line head 15 and sent at a predetermined speed to be ejected from the paper ejection port 53.

7 and 8 show the thermal line head 15
The support mode of the swing shaft 15a is shown. The support frames 55, 56 are formed with elongated holes 55a, 56a in a substantially vertical direction. The swing shaft 15 is formed in the elongated holes 55a, 56a.
a is fitted so as to be rotatable and movable. When the swing shaft 15a is rigidly supported so as to be rotatable only, when the four points A, B, C, and D on the head 15 shown in FIG. The vicinity of the point is separated from the platen roller 14 and uneven printing occurs. On the other hand, as described above, when the swing shaft 15a is movably supported, the head 15 is pressed against the platen roller 14 by the leaf spring 51, and the plane of the head 15 is always at three points A, C, D, or Since it is determined by B, C, and D, such print unevenness does not occur.

A control board 60 of the printer is located on the bottom wall 50d of the casing 50, avoiding the leaf spring 51 and the thermal line head 15. That is, the plane shape of the control board 60 secures the maximum effective area by cutting out the portion of the leaf spring 51. FIG. 6 is a plan view of the substrate 60. Further, the electronic component 61 such as an IC on the control board 60 does not interfere with the thermal line head 15 even when the thermal line head 15 is pushed down against the force of the leaf spring 51 as shown in FIG. Its size and position are defined. As shown in FIG. 4, a space for installing (attaching / detaching) the ink ribbon cassette 30 is secured on the upper surface of the upper wall 50a of the casing 50 at the side of the paper insertion opening 52.

A battery chamber 63 is formed on the side wall 50c of the casing 50. This battery chamber 63 is at a position different from that of the drive motor 57 (FIG. 2), and the drive motor 5
When viewed from the axial direction of 7, the batteries 64 housed in the battery chamber 63 in two upper and lower stages and the drive motor 57 are provided in a positional relationship where they overlap each other (see FIGS. 3 and 5).

The platen roller 14, the thermal head 15, the drive motor 57, the control board 60, and the electronic component 6 described above.
By arranging 1 and the battery chamber 63 (battery 64), the casing 50, that is, the entire printer can be further downsized. Further, in particular, according to the arrangement of the platen roller 14, the thermal head 15, the sheet insertion port 52, and the sheet ejection port 53 described above, the sheet 20 is hardly bent in the casing 50, and the sheet positioned in the casing 50 is not required. Since the area of 20 can be reduced, paper jamming in the casing 50 is less likely to occur.

The ink ribbon cassette 30 shown in FIG.
An ink ribbon 33 wound around a winding core 32 is rotatably housed in a cassette case 31, and the ink ribbon 33 pulled out from the winding core 32 is guided from an ink ribbon outlet 34 into a paper insertion opening 52. . Cassette case 31
A leaf spring (not shown) for pressing the ink ribbon 33 against the winding core 32 is fixed therein, and the leaf spring prevents the ink ribbon 33 from loosening and applies a predetermined tension to pulling out the ink ribbon 33.

The thermal line printer having the above structure is
The superposed paper 20 and the ink ribbon 33 are inserted from the paper insertion opening 52, feed is given by the rotational driving force of the platen roller 14, and print information is given to the thermal line head 15 in synchronism with this feed, whereby the paper 20 is fed. Can be printed. Specifically, the paper 20 is inserted into the paper insertion opening 52, and the platen roller 14 is driven to rotate slightly in the forward direction to bring the paper 20 and the ink ribbon 33 into close contact with each other. The ink ribbon 33 has, for example, an adhesive layer, and when the platen roller 14 is driven in the normal direction, the leading end portion of the ink ribbon 33 and the paper 20 are bonded. In this state, when the platen roller 14 is rotationally driven at a predetermined speed while applying the print information to the thermal line head 15, the ink layer of the ink ribbon 33 to which the print information is applied is selectively melted and transferred to the paper 20. It

The printed paper 20 and the ink ribbon 3
The sheet 3 is discharged from the sheet discharge port 53. The platen roller 14 rotates by the number of rotations corresponding to the size of the sheet 20 and stops. Therefore, the paper 20 can be separated from the ink ribbon 33 and taken out.

During maintenance, the thermal line head 15 can be separated from the platen roller 14 by pushing down against the leaf spring 51, as shown in FIG.
Maintenance around 5 times can be performed easily.

As described above, in the thermal line printer of this embodiment, the platen roller 14, the thermal head 15, the drive motor 57, the control board 60, the electronic component 61, and the battery chamber 63 (battery 6) in the casing 50.
Since 4) is efficiently arranged, the printer can be downsized. Further, although the printing mode using the ink ribbon has been described above, the present thermal line printer is configured to cut the cut paper (paper) 20 such as thermal paper or peel-off paper.
However, when a plurality of sheets are supplied between the platen roller 14 and the thermal line head 15 in a superposed manner, the following separating operation is performed to feed only the sheet 20 on the platen roller 14 side without using a special separating member. Have

FIG. 9 is a diagram for analyzing a condition for obtaining a separating action for feeding only the sheet 20 on the platen roller 14 side by the platen roller 14 and the thermal line head 15 without using a special separating member. Is.

Now, when the overlapped first and second sheets 20 are supplied between the platen roller 14 and the thermal line head 15, the platen roller is brought into contact with the first sheet 20 contacting the platen roller 14. The force in the feed direction given by 14 is F1, and the force in the feed direction given to the second paper 20 by the frictional force of the first paper 20 is F2,
The force acting between the paper 20 and the head in the direction opposite to the feed direction is F3S, and the force acting between the second paper 20 and the casing in the direction opposite to the feed direction is FG, the second paper 2
The wedge effect force for preventing 0 from entering the gap between the first paper 20 and the thermal line head 15 is F3K, F3S + F3K + FG = F3 ′, and F3 ′ is the drag force acting on the second paper in the opposite direction. Therefore, if F1> F3 '> F2 (1) F3K>F2> F3S + FG (2) is satisfied, no special separating member is required. The paper 20 can be sorted. The conditional expression (1) is a condition for surely separating the two sheets of paper, and the condition (2) is for surely conveying the second paper to a position that satisfies the expression (1). It is a condition. Considering the properties of the paper 20 and the thermal line head 15, the material of the platen roller 14,
The hardness, diameter, etc. may be determined so as to satisfy the above conditions. Further, even if there are third, fourth, ... Papers after the second paper, since the second paper is stopped under the condition (1), the conveying force is transmitted to the second and subsequent papers. There is no such thing.

Therefore, by satisfying the above conditions, it is possible to eliminate the need for a special sheet separating mechanism, and in combination with the above-mentioned efficient member arrangement in the casing, a plurality of sheets can be supplied. Even in the printing mode, it is possible to obtain a small thermal head printer by simplifying the structure of the printer.

[0024]

According to the present invention, a thermal line printer having a simple structure and a small size can be obtained.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional perspective view showing an embodiment of a thermal line printer according to the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a gear train showing the drive system of FIG.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

5 is a cross-sectional view showing a state where the thermal line head is pushed down in FIG.

FIG. 6 is a plan view of a substrate.

FIG. 7 is a perspective view showing a support mode of a swing shaft of the thermal line head.

FIG. 8 is a side view of the same.

FIG. 9 is a diagram showing a sheet separating function by a platen roller and a thermal line head.

[Explanation of symbols]

14 Platen roller 15 Thermal line head 15a swing axis 20 sheets 30 ink ribbon cassette 31 cassette case 32 winding core 33 ink ribbon 50 casing 51 leaf spring 52 Paper insertion slot 53 Paper outlet 55 56 Support frame 57 Drive motor 58 gear train 60 Control board 61 Electronic components 63 Battery room 64 batteries

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification symbol FI B41J 29/00 (72) Inventor Kiyoshi Negishi 2-39 Maenocho, Itabashi-ku, Tokyo Within Asahi Optical Co., Ltd. (72) Inventor Katsumi Kawamura 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Asahi Optical Co., Ltd. (72) Inventor Katsuka Suzuki 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Asahi Optical Co., Ltd. (72 ) Inventor Toshinoma Yamanaka 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Asahi Optical Co., Ltd. (72) Inventor Atsushi Kidera 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Asahi Optical Co., Ltd. (72 ) Inventor Mikio Horie 2-36-9 Maeno-cho, Itabashi-ku, Tokyo Inside Asahi Optical Co., Ltd. (56) Reference JP-A-1-170164 (JP, A) JP-A-212923 (JP, A) JP-A-4-135773 ( JP, A) JP-A-5-57991 (JP, A) Actual development Sho 59-114660 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/325 B41J 2/32 B41J 11/04 B41J 25/312 B41J 25/316 B41J 29/00

Claims (7)

(57) [Claims] 1. A substantially rectangular parallelepiped casing having substantially parallel upper and bottom walls, and both side walls substantially orthogonal to the upper and bottom walls; formed on the upper wall and one side wall of the casing, respectively. An insertion port and an ejection port for the printing paper in a direction parallel to the ridgeline formed by the upper wall and the side wall; and a paper path of the printing paper from the insertion port to the ejection port and the ridgeline in the casing. A platen roller which is positioned in a casing corner space to be formed and is rotatably supported with a rotation axis in a direction parallel to the ridge line; and the platen roller disposed at one end of the casing for rotation. The motor and its drive gear train, and the paper path from the above-mentioned insertion port to the ejection port of the casing.
Located on the opposite side of the platen roller and above the ridge.
Can be elastically contacted with the platen roller by being biased toward the line
Thermal line printer, which is equipped with an effective thermal line head . 2. A thermal line printer according to claim 1.
In, the upper wall that forms the casing corner space
And side walls, and the roller surface of the platen roller above
The distance between the roller and the platen
Thermal line pudding smaller than radius size
Ta. 3. The thermal line printer according to claim 1 or 2, wherein the thermal line head is swingable about a swing shaft, and is spaced apart in the swing shaft direction.
Engage with the bottom wall of the ring and the back of the thermal line head
A thermal line printer in which at least two V-shaped leaf springs are biased toward a platen roller. 4. The thermal line printer according to claim 3 , wherein a printer control board is provided at the bottom of the casing, avoiding the leaf spring and the thermal line head. 5. The thermal line printer according to claim 3 , wherein the swing axis of the thermal line head is
A thermal line printer provided parallel to the rotation axis of a platen roller and movably supported in a direction against the force of the leaf spring for urging the thermal line head toward the platen roller. 6. A thermal line printer according to any one of claims 1 to 5, the platen roller and the thermal line head, when a plurality of sheets superimposed therebetween is supplied, the the paper A thermal line printer that separates and feeds only the paper on the platen roller side. 7. The thermal line printer according to claim 6 , wherein when the superposed first and second sheets are supplied between the platen roller and the thermal line head, the following conditions (1) and (2) are satisfied. ) Is satisfied, the thermal line printer. (1) F1> F3 '> F2 (2) F3K>F2> F3S + FG where F1: force in the feeding direction given by the platen roller to the first sheet in contact with the platen roller, F2: with the first sheet Force in the feed direction given to the second paper by friction, F3 ': Drag force acting on the second paper in the opposite direction to the feed direction, F3K: Gap between the first paper and the thermal line head in the second paper W3 effect force for not entering into the paper, F3S: Force acting between the thermal line head and the paper in the direction opposite to the feed direction, FG: Force acting between the second paper and the casing in the direction opposite to the feed direction .