JPH0415508Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a thermal printer, and particularly to a thermal printer with an improved feeding mechanism for a thermal transfer ribbon.

[Background of the idea]

Figures 1 to 3 are explanatory diagrams showing the schematic configuration of a thermal printer previously proposed by the applicant.
The figure is an exploded perspective view of the main part, Figure 2 is a side view of the main part, and Figure 3 is a side view of the main part.
The figure is an explanatory diagram illustrating a printing operation.

In these figures, 1 is a thermal transfer ribbon, 2 is a ribbon case in which this thermal transfer ribbon 1 is stored,
3 is a cassette holder that holds this ribbon case 2;
4 is inserted into the hole formed in the ribbon case 2,
This is a sprocket for feeding the thermal transfer ribbon 1. Bent parts 3a and 3b having holes into which the support shaft 5 is inserted are formed at both rear ends of the cassette holder 3, and a bent part 3c for supporting the post 6 is formed in the center of the cassette holder 3. It has been done. The above-mentioned post 6 is inserted into a groove 9 of a cam 8 that rotates integrally with the shaft 7, as shown in FIG. Further, a gear 10 is attached to the shaft 7, and the rotational force of a gear 12 attached to a motor 11 is transmitted to the gear 10. In addition, 13 shown in FIG. 2 is a thermal head mounted on a carriage (not shown), 14 is a platen, and 15 is a recording paper wound around this platen 14.

With the thermal head constructed in this way, printing is performed as follows.

That is, when the groove 9 of the cam 8 and the post 6 are in the engaged state shown in FIG. 2, the ribbon case 2 is in the position 2a shown by the solid line in the same figure, and therefore the thermal transfer ribbon 1 is in the state shown in the position 1a. It is in. In this state, when the thermal head 13 is energized and pressed against the platen 14, the heat-fusible material of the thermal transfer ribbon 1 is melted and transferred onto the recording paper 15, and printing is performed. In this way, for example, the upper line 16a of the thermal transfer ribbon 1 shown in FIG. 3 is used.

Further, when the shaft 7 is rotated from the above state in the direction of the arrow 17 in FIG. 2 until the portion 9a of the groove 9 of the cam 8 and the post 6 are engaged, the ribbon case 2 rises to the position 2b, The thermal transfer ribbon 1 is in the state shown at position 1b. In this state, the thermal head 13 is energized and the thermal head 1
3 onto the platen 14, the thermal transfer ribbon 1
material is transferred onto the recording paper 15. In this way, the middle line 16b of the thermal transfer ribbon 1 shown in FIG. 3 is used.

Also, from the above state, the shaft 7 is further moved to the second position.
When the cam 8 is rotated in the direction of the arrow 17 until the post 6 engages with the portion 9b of the groove 9, the ribbon case 2 rises to the position 2c, and the thermal transfer ribbon 1
is in the state shown at position 1c. In this state, when the thermal head 13 is energized, the material of the thermal transfer ribbon 1 is transferred onto the recording paper 15. In this way, the lower line 16c of the thermal transfer ribbon 1 shown in FIG. 3 is used.

Thereafter, printing is performed in the same manner, and the thermal transfer ribbon 1 is printed in an area 16d corresponding to one track shown in FIG.
, upper line 16e, middle line 16
f, the lower line 16g is used, and after passing through the area 16h for one track, the upper line 16
i, the middle line 16j, and the lower line 16k are sequentially used. In addition, the upper stage of the thermal transfer ribbon 1,
Widths of middle and lower lines 18a, 18b, 18c
are set to have the same dimensions, for example.

By the way, in the case of a thermal printer configured in this way, printing is possible when the carriage (not shown) moves from left to right, and printing when the carriage moves from right to left, that is, bidirectional printing. Although it has the advantage of realizing high-speed printing because it can be implemented, it has the following problems.

(1) As shown in Fig. 3, the thermal transfer ribbon 1 is
Since the ribbon case 2 has a large width corresponding to the middle and lower lines, the height of the ribbon case 2 increases, and the overall height increases accordingly.

(2) Although not shown above, this thermal printer uses a rack installed along the platen as a ribbon feeding mechanism that enables printing in both left and right directions, such as lines 16a, 16b, and 16c. The structure is complicated, as it includes a gear system including a gear that can be engaged with the rack, as well as a cam mechanism that releases the engagement between the rack and the gear.

(3) The thermal transfer ribbon 1 requires areas 16d, 16h, etc. that are not used for printing at regular intervals,
Therefore, the usage efficiency of the thermal transfer ribbon 1 is low.

[Purpose of invention]

The present invention was developed in view of the problems in the conventional technology, and its purpose is to be able to perform bidirectional printing, to minimize the width of the thermal transfer ribbon, and to improve the ribbon feeding mechanism. An object of the present invention is to provide a thermal printer that can simplify the process and improve the efficiency of using a thermal transfer ribbon.

[Summary of the idea]

In order to achieve this object, the present invention includes a platen, a carriage, a ribbon case in which a thermal head attached to the cartridge and a thermal transfer ribbon are housed, and a ribbon case provided with the ribbon case to hold both ends of the thermal transfer ribbon, respectively. two ribbon winding cores, two ribbon winding means for transmitting rotational force to each of the two ribbon winding cores, and a carriage moving mechanism for reciprocating the carriage in the digit direction along the platen; A first drive source that drives the carriage moving mechanism, a rack disposed parallel to the platen, and a thermal head provided on the carriage that can be engaged with the rack while being in pressure contact with the platen. a gear, a transmission means that engages with the gear and selectively transmits rotational force to either one of the ribbon winding means depending on the direction of movement of the carriage, and is formed within the ribbon case and guides the thermal transfer ribbon. a ribbon post, a pressure roller that is arranged to face the ribbon post and transfers the ribbon post and the thermal transfer ribbon by pressing them together; a belt that is arranged parallel to the rack with a gap therebetween; and a belt that is in a non-printing state. a pulley capable of engaging with the belt and provided integrally and coaxially with the pressing roller;
a belt drive means for driving the belt; a transmission means for selectively transmitting the rotational force of a second drive source to the belt drive means during non-printing operations; holding means for holding the ribbon in a state where it is not engaged with the belt, and during a printing operation, by moving the carriage, the gear engaged with the rack is rotated to wind up the ribbon, and during a non-printing operation, the carriage is moved. In some cases, the belt is driven in a state where the belt and the pulley are engaged with each other, so that the ribbon post and the pressure roller press the thermal transfer ribbon and feed the ribbon.

[Example of idea]

Hereinafter, one embodiment of the thermal printer of the present invention will be described based on FIGS. 4 to 9 a, b, c, and d.

Fig. 4 is an overall perspective view including a partially broken part, Fig. 5
The figure is a perspective view showing an enlarged ribbon case portion. In these figures, 21a is the right frame, 21b is the left frame, and 21c is the bottom frame. 22 is a shift motor attached to the right frame 21a, and its power is supplied to the wire pulley 2.
3. Wire 26 wound around pulleys 24 and 25
is transmitted to the carriage 27 via.

Reference numeral 28 denotes a paper feed motor attached to the left frame 21b, the power of which is transmitted to a roller 32 via a pinion gear 29, an idle gear 30, and a paper feed gear 31, and drives recording paper (not shown) inserted along a paper guide 33. The paper is fed by pressing the roller 32 with a pinch roller (not shown).

34 is a platen holder provided on the bottom frame 21c, and a platen 35 is fixedly installed on the upper part.
A rack 36 is fixedly attached to the lower part. 37
A shaft 37 is held between the right frame 21a and the left frame 21b, and a bearing portion 38 of the carriage 27 is slidably engaged with the shaft 37.

A head holder 40 that holds the thermal head 39 and a ribbon case 42 that accommodates the thermal transfer ribbon 41 are attached to the above-mentioned carriage 27.
A slider portion 43 is also formed. The slider portion 43 is slidably engaged with a head pressing spring 44 attached to the right frame 21a and the left frame 21b and a slider receiver 45 held by the shaft 37. Further, a protrusion 45a is formed at one end of the slider receiver 45, and a solenoid 46 fixed to the left frame 21b is brought into contact with this protrusion 45a.

Further, as shown in FIG. 5, the thermal transfer ribbon 41 described above is held at both ends by ribbon-wound cores 47a, 47b, and ribbon posts 48a, 48b,
48c and along a predetermined route. 49 is a gear that engages with the rack 36; 50a;
50b is an idle gear that engages with gear 49; 51;
is a gear stay that holds these gears 49, 50a, 50b, and 52a, 52b are gears 50, respectively.
This is a gear that can be engaged with the gears a and 50b. 53a, 5
3b is a sprocket that engages with ribbon-wound cores 47a and 47b, respectively, and gears 52a and 47b, respectively.
52b, and is rotatable as the gears 52a and 52b rotate.

Further, 85 shown in FIG. 4 is the left side frame 21b.
86 is a switching lever whose one end faces the solenoid 85 and the other end engages with the pinion gear 29, and 87 is a spring that biases the switching lever 86 away from the solenoid 85. , 88 are gears with which the pinion gear 29 can engage. When the solenoid 85 is not energized, the force of the spring 87 causes the switching lever 86 to switch the pinion gear 29 to engage the idle gear 30, and when the solenoid 85 is energized, the force of the spring 87 causes the switching lever 86 to switch the pinion gear 29 to engage the idle gear 30. One end of the switching lever 86 is attracted to the solenoid 85 against this, and thereby the switching lever 86 switches the pinion gear 29 to engage the gear 88 . 89 is gear 8
8, a wire that transmits the rotational force; 90, a pulley having a small diameter portion around which the wire 89 is wound; 91, a pulley disposed on the opposite side of the pulley 90; 92, a wire wound around the large diameter portion of the pulley 90 and the pulley 91; A rotating belt, for example a toothed belt.

Further, 59 shown in FIG. 4 and FIG.
The ribbon post 48c provided on the ribbon case 42 can be opposed to the ribbon post 48c. 60 is a roller shaft that rotatably supports the pressure roller 59;
Reference numeral 94 denotes a pulley disposed, for example, coaxially with the pressing roller 59 via the roller shaft 60.
This pulley 94 can be engaged with the toothed belt 92 described above. 55 is roller shaft 60
This is a swinging arm that swingably holds the arm, and is rotatably supported by the carriage 27 by an arm post 95. Reference numeral 96 denotes an arm spring, which has one end attached to the swinging arm 55 and the other end attached to the carriage 27, and holds the swinging arm 55 in the state shown in FIG. 5 during printing operations, etc. do. That is, at this time, the pressure roller 59 presses the thermal transfer ribbon 41
The pulley 94 is not in contact with the toothed belt 92.

The above-mentioned solenoid 85, switching lever 86, spring 87, pinion gear 29, gear 88, wire 8
9, pulleys 90, 91, 94, toothed belt 9
2. The roller shaft 60, the swing arm 55, the arm post 95, and the arm spring 96 constitute a transmission means for transmitting the rotational force of the paper feed motor 28 to the pressure roller 59.

Next, the above-mentioned figures 4 and 5 and figures 6 a, b ~
The operation of this embodiment will be explained with reference to FIGS. 9a, b, c, and d.

Note that FIG. 6a is a plan view showing the ribbon case portion during forward printing, FIG. 6b is a front view showing the thermal transfer ribbon portion during forward printing, and FIG. 7 is a ribbon case portion during thermal transfer ribbon feeding operation. FIG. 8a is a plan view showing the ribbon case portion during backward printing; FIG. 8b is a front view showing the thermal transfer ribbon portion during backward printing; FIGS. 9 a, b, c, d FIG. 2 is an explanatory diagram illustrating a printing process.

First, during the forward printing shown in FIG. 6a, the solenoid 46 in FIG. 4 is not energized;
Therefore, the thermal head 39 presses the recording paper and thermal transfer ribbon 41 against the platen 35 by the force of the pressing spring 44, and the rack 36 and the gear 49 are brought into engagement. In this state, when the thermal head 39 is energized and the shift motor 22 is driven in a predetermined rotational direction, the wire pulley 23 rotates, the wire 26 moves, and the carriage 27 is guided by the shaft 37, as shown in FIG. and move in the direction of arrow 61 in FIG. 6a.

At this time, as the carriage 27 moves in the direction of arrow 61, the gear 49 that engages with the rack 36 rotates in the direction of arrow 62 in FIG. 51 swings in the direction of arrow 64. By this,
The rotation of the gear 49 is transmitted as the rotation of the gear 52b in the direction of arrow 65, and the ribbon-wound core 47b rotates in the direction of arrow 65 via the sprocket 53b, and the thermal transfer ribbon 41 rotates in the direction of arrow 66a, 66b, 6.
6c, 66d, 66e, and 66f are sent in this order and wound around the ribbon winding core 47b.

FIG. 6b shows a portion of the thermal transfer ribbon 41 at this time, and as the thermal head 39 moves in the direction of arrow 61, the thermal transfer ribbon 41 moves in the direction of arrow 66, and the heat generating portion 67 of the thermal head 39 moves the thermal transfer ribbon 41 in the direction of arrow 66. The material of the thermal transfer ribbon 41 is then transferred to the recording paper and printing is performed on the recording paper, and a used portion 41a is formed on the thermal transfer ribbon 41.

In this way, as shown in FIG. 9A, for example, forward printing is performed using the portion of the thermal transfer ribbon 41 between positions ○A and ○R.

Next, as a preparatory operation for carrying out return printing, an operation is performed to feed the thermal transfer ribbon 41 so that the position C shown in FIG. 9A is at the position of the thermal head 39.

That is, the solenoid 46 shown in FIG. 4 is energized, which causes the slider holder 45 to rotate in the direction of arrow 68 about the shaft 37 as a fulcrum against the force of the spring 44, thereby reducing the pressure of the thermal head 39 against the platen 35. When released, the engagement between the rack 36 and the gear 49 is released, as shown in FIG. In this state, when the thermal head 39 is de-energized and the solenoid 85 shown in FIG. is attracted to the solenoid 85, and the pinion gear 29, which rotates as the paper feed motor 28 is driven, engages the gear 88, and as the gear 88 rotates, the wire 89
moves, which causes pulley 90 to rotate and toothed belt 92 to move in the direction of arrow 97 in FIG. On the other hand, as the slider receiver 45 is rotated in the direction of the arrow 68 shown in FIG. 4, the ribbon case 4
2 approaches the toothed belt 92, whereby the ribbon post 48c presses the thermal transfer ribbon 41 against the pressure roller 59, and the pulley 94 engages with the toothed belt 92. Therefore, the toothed belt 92
As the pulley 9 moves in the direction of the arrow 97 mentioned above,
4 rotates in the direction of arrow 71 in FIG. arrow 7
The thermal transfer ribbon 41 rotates in two directions, and the thermal transfer ribbon 41
a, 73b, 73c, 73d, and 73e, and reach the position of the thermal head 39 at position ○c in FIG. 9a.

Then, printing on the return trip is started from this state. That is, when the solenoid 46 shown in FIG. 4 is de-energized, the thermal head 39 presses the recording paper and thermal transfer ribbon 41 against the platen 35 by the force of the pressing spring 44, as shown in FIG. 8a. 36 and gear 49 are engaged. Note that the engagement between the pulley 94 and the toothed belt 92 and the pressure contact of the thermal transfer ribbon 41 between the press roller 59 and the ribbon post 48c are both released at this time. Here, the thermal head 39 is energized, and the digit feed motor 22 is
When the carriage 27 is driven in the opposite direction of rotation to that described above, the carriage 27 moves in the direction of the arrow 74 in FIGS. 4 and 8a via the wire pulley 23 and the wire 26.

At this time, as the carriage 27 moves in the direction of arrow 74, the gear 49 that engages with the rack 36 rotates in the direction of arrow 75 in FIG. 8a, and at the same time, the idle gear 50a rotates in the direction of arrow 76. The gear stay 51 swings in the direction of arrow 77. As a result, the rotation of the gear 49 is transmitted as the rotation of the gear 52a in the direction of the arrow 78, the ribbon-wound core 47a rotates in the direction of the arrow 78 via the sprocket 53a, and the thermal transfer ribbon 41 is rotated in the direction of the arrow 79a, 79b, 7.
9c, 79d, 79e, and 79f are sent in this order and wound around the ribbon-wound core 47a.

FIG. 8b shows the thermal transfer ribbon 41 at this time, and as the thermal head 39 moves in the direction of arrow 74, the thermal transfer ribbon 41 moves in the direction of arrow 79, and the heat generating portion 67 of the thermal head 39 moves the thermal transfer ribbon 41 in the direction of arrow 79. The material of the thermal transfer ribbon 41 is then transferred to the recording paper, printing is performed on the recording paper, and a used portion 41a is formed on the thermal transfer ribbon 41.

In this way, as shown in Figure 9b and c,
Return printing is performed using the portion of the thermal transfer ribbon 41 between positions ◯ and ◯.

Next, as a preparatory operation for carrying out forward printing, an operation is carried out to feed the thermal transfer ribbon 41 so that the position C shown in FIG. 9C is at the position of the thermal head 39, as shown in FIG. Then, forward printing is performed in the same manner as shown in FIG. 6a described above. FIG. 9d shows the state when this forward printing is started. Thereafter, such operations are continuously repeated depending on the amount of printing.

In one embodiment configured in this way,
In addition to being able to print in both left and right directions, the thermal transfer ribbon 41 can be used as illustrated in FIG. 9a.
The width 80 can be suppressed, for example, to a size that allows printing of one character, that is, 1/3 of the width of the thermal transfer ribbon 1 shown in FIG. 3 described above. Furthermore, as shown in FIG. 7, the engagement between the rack 36 and the gear 49 can be released without intervening a cam mechanism, and the thermal transfer ribbon 41 is fed by the paper feed motor 28 or the like. , the structure is simple. Further, as shown in FIGS. 9a to 9d, the thermal transfer ribbon 4
1. Since there is no area that is not used for printing when switching between forward printing and return printing, the third
Compared to the case of the thermal transfer ribbon 1 shown in the figure,
The efficiency of using the thermal transfer ribbon 41 is improved.

Although not specified in the above examples,
The dimensions of the portion of the thermal transfer ribbon 41 where outward printing is performed (for example, between position ○a and position ○ro in FIG. 9),
The dimensions of the portion where the backward printing is performed (for example, between position ○ B and position ○ C in FIG. 9) may be set to be the same or may be set to be different. If the dimensions are set to be the same, the feed amount of the thermal transfer ribbon 41 illustrated in FIG. 7 will always be constant. Further, when different dimensions are set, it is necessary to constantly count the number of digits printed by the thermal head 39, but this can be easily accomplished by detecting the number of rotations of the digit feed motor 22, etc.

[Effect of idea]

Since the thermal printer of the present invention is configured as described above, it is possible to print in both left and right directions, and also to minimize the width of the thermal transfer ribbon, thereby reducing the height of the ribbon case. The thermal printer can be made smaller.

Furthermore, the engagement between the rack and the gear that engages with the rack can be released without intervening a cam mechanism, and the thermal transfer ribbon can be fed in this state, so the structure of the ribbon feeding mechanism is simple. Manufacturing costs can be reduced.

Furthermore, since there is no portion of the thermal transfer ribbon that is not used for printing, the efficiency of using the thermal transfer ribbon is improved and the running cost is low.

[Brief explanation of the drawing]

Figures 1 to 3 are explanatory diagrams showing the schematic configuration of a thermal printer previously proposed by the applicant.
The figure is an exploded perspective view of the main part, Figure 2 is a side view of the main part, and Figure 3 is a side view of the main part.
The figure is an explanatory diagram illustrating a printing operation, and FIGS. 4 to 9 a, b, c, and d are explanatory diagrams illustrating an embodiment of the thermal printer of the present invention, and FIG. 4 includes a partially broken part. 5 is an enlarged perspective view of the ribbon case portion, FIG. 6a is a plan view of the ribbon case portion during forward printing, and FIG. 6b is a thermal transfer ribbon portion during forward printing. 7 is a plan view showing the ribbon case portion during thermal transfer ribbon feeding operation, FIG. 8 a is a plan view showing the ribbon case portion during backward printing, and FIG. 8 b is a plan view showing the ribbon case portion during backward printing. A front view showing the ribbon portion, and FIGS. 9a, b, c, and d are explanatory diagrams illustrating the printing process. 28... Paper feed motor, 29... Pinion gear, 41... Thermal transfer ribbon, 42... Ribbon case, 48c... Ribbon post, 55... Swinging arm, 59... Pressing roller, 60... Roller shaft, 85 ...Solenoid, 86...Switching lever,
87...Spring, 88...Gear, 89...Wire,
90, 91, 94...Pulley, 92...Toothed belt, 95...Arm post, 96...Arm spring.

Claims (1)

[Scope of Claim for Utility Model Registration] A platen, a carriage, a ribbon case in which a thermal head attached to the carriage and a thermal transfer ribbon are housed, and two parts provided in the ribbon case and holding both ends of the thermal transfer ribbon, respectively. two ribbon winding means for transmitting rotational force to each of the two ribbon winding cores; a carriage movement mechanism for reciprocating the carriage in the digit direction along the platen; a first drive source that drives the mechanism; a rack disposed parallel to the platen; a gear that can be engaged with the rack when a thermal head provided on the carriage is in pressure contact with the platen; a transmission means that engages with the gear and selectively transmits rotational force to either one of the ribbon winding means depending on the moving direction of the carriage; and a ribbon post that is formed in the ribbon case and guides the thermal transfer ribbon. , a pressure roller that is arranged to face the ribbon post and transfers the ribbon post and the thermal transfer ribbon by pressure contact; a belt that is arranged parallel to the rack and with a gap therebetween; and a belt that is in a non-printing state. a pulley disposed integrally and coaxially with the pressure roller; a belt drive means for driving the belt; and a pulley for selectively transmitting the rotational force of a second drive source to the belt drive means during non-printing operations. a transmission means; and a holding means for holding the pressure roller in a state in which it does not contact the thermal transfer ribbon and the pulley does not engage with the belt, and during a printing operation, by moving the carriage, The easily engaged gear is rotated to wind up the ribbon, and during non-printing operations, the belt is driven while the belt and pulley are engaged, so that the ribbon post and the pressure roller can move the thermal transfer ribbon. A thermal printer characterized by having a structure in which a ribbon is fed by press-contacting the ribbon.