JPH0333482Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) This invention relates to a thermal transfer printer that generates heat in a thermal printing head to transfer ink coated on a thermal transfer ribbon to printing paper made of plain paper.

(Prior Art) During printing with this type of thermal transfer printer, the thermal transfer ribbon is held in pressure contact between the printing paper on the platen surface and the thermal printing head on the carrier. Then, as the carrier moves, the ribbon moves relative to the printing paper, and the thermal transfer ribbon is sequentially fed out from the supply spool of the ribbon cassette through the outlet opening, passes in front of the thermal printing head, and then passes through the inlet opening to the ribbon. It is configured to be drawn into a cassette and wound onto a take-up spool.

In such a configuration, conventionally, when a ribbon cassette is mounted on a carrier, the portion of the thermal transfer ribbon exposed outside the cassette between the exit opening and the entrance opening is placed between the thermal printing head and the platen, or on the carrier. The ribbon cassette is carefully inserted through the upper ribbon guide and then latched onto the latching member on the carrier. I had to wear it.

〔the purpose〕

This invention was made in order to eliminate this type of conventional inconvenience, and its purpose is to provide a thermal transfer printer in which a ribbon cassette can be attached extremely easily.

〔Example〕

An embodiment embodying this invention will be described below based on the drawings. As shown in FIG. 1, a platen 2 serving as a paper support device is rotatably supported between both side plates 1 of the printer and is driven by a paper feed motor 3 disposed outside the right side plate 1. As shown in FIG. Below the platen 2, between the side plates 1, as shown in FIG. A rack 16 extending in the left-right direction is formed integrally with the paper guide table 4.

As shown in FIG. 1, a guide rod 5 is supported between both side plates 1 in front of the platen 2, and swing levers 6 are pivotally attached to both ends of the guide rod 5, respectively. A head release plate 7 is installed between the front parts of both swing levers 6, and this head release plate 7 is always maintained by a tension spring 8 stretched between the tips of both swing levers 6 and the side plate 1. It can swing slightly up and down while being biased upward.

Further, a solenoid 9 is disposed on the outside of the left side plate 1, and a solenoid lever 11 is supported on the lower front edge of the yoke portion 10 so as to be rotatable within a predetermined angle. The rear horizontal surface 12 of the solenoid lever 11 is arranged opposite to the lower surface of the solenoid 9, and the lower end of the adjusting screw 13 screwed onto the front part of the solenoid lever 11 is always connected to the engagement screw fixed to one side end of the head release plate 7. It is in contact with the upper surface of the plywood 38. When the solenoid 9 is energized, its horizontal surface 12 is attracted to the lower surface of the solenoid 9, the solenoid lever 11 is rotated clockwise in the figure, and the adjustment screw 13 pushes down the head release plate 7 against the tension spring 8. .

As shown in FIGS. 1 and 2, the guide rod 5
A carrier 14 is inserted into the upper portion and supported by its lower cylindrical portion 15 so as to be movable left and right. This carrier 1
4 includes a drive pulley 18 which is interlocked with a carrier drive motor 17 disposed on the outside of the right side plate 1;
A drive wire 20 is fixed in tension between a driven pulley 19 supported on the left side plate 1, and as the drive pulley 18 rotates, the carrier 14 is guided by the guide rod 5 and moved along the platen 2 surface. It moves from side to side. Further, the tip of the forward protrusion 21 of the carrier 14 is locked to the front edge of the head release plate 7, and when the solenoid 9 is energized, the carrier 14 is moved to the guide rod 5 via the head release plate 7.
It is tilted slightly toward the front and lower part of the body.

As shown in FIG. 3, a planar, approximately L-shaped support plate 23 is swingably supported by fixing pins 22 at the rear side of the carrier 14, and an engagement gear 24 is supported at the intermediate portion thereof. has been done. This engagement gear 2
4 is always urged backward by the action of a spring 25 attached to the support plate 23, and during printing, it is engaged with the rack 16 of the paper guide stand 4, and as the carrier 14 moves, its rotation is caused by the rotation of the three The signal is transmitted via idle gears 26, 27, and 28 to a ribbon drive gear 29, which will be described next.

As shown in FIG. 2, a large-diameter portion 31 is provided at the lower end of the support shaft 30 erected at the center of the bottom surface of the carrier 14.
A camshaft 32 having an integral body is rotatably fitted therein, and a ribbon drive cam 33 is fitted and fixed to the upper end of this camshaft 32. The engagement gear 2 is disposed on the outer periphery of the camshaft 32.
A clutch plate 34 made of felt is provided between the lower surface of the ribbon drive gear 29 and the large diameter portion 31, and a clutch plate 34 made of felt is provided between the upper surface and the ribbon drive cam 33. A compression spring 35 is interposed between them. Due to the action of this compression spring 35, the clutch plate 34 is pressed and held between the ribbon drive gear 29 and the large diameter portion 31, and the camshaft 32 can rotate with slippage relative to the rotation of the ribbon drive gear 29. It's becoming like that. Therefore, as shown in FIG. 3, when the carrier 14 moves in the printing direction, the ribbon drive cam 33 is rotated counterclockwise via the gears 24, 26, 27, 28, 29 and the camshaft 32. .

Further, as shown in FIGS. 2 and 3, a metal heat dissipating plate 36 that also serves as a head holder is mounted on the back of one side of the carrier 14, and is connected to a ribbon drive cam 33 or a support piece 44 (described later) as shown in FIG. The head holder 36 is assembled in such a manner that it protrudes upward, and a thermal printing head 37 containing a plurality of heating elements (not shown) is attached to the rear surface of the head holder 36. During printing, this thermal printing head 37 is held in a state in which its surface is in contact with the printing paper P made of plain paper on the platen 2 via a thermal transfer ribbon 49, which will be described later, by the action of the tension spring 8. At the same time, when the solenoid 9 is energized, the surface of the carrier 14 is placed at a release position away from the printing paper P as the carrier 14 is tilted.

Next, the structure of the ribbon cassette 41 which is detachably mounted on the carrier 14 will be explained.

As shown in FIGS. 1 and 2, a support body 42 is fixed to the upper surface of the carrier 14, and a through hole 43 is formed in the center of the support body 42 through which the ribbon drive cam 33 and the like are inserted. Three support pieces 44 for hanging the ribbon cassette 41 on the support body 41 are erected on the top. Each support piece 44 is placed on this support body 42 as shown in FIG.
The case body 45 of the ribbon cassette 41 is placed in a state in which the ribbon cassette 41 is positioned at a recess 46 having a width slightly larger than the width of the head holder 36 at the rear of one side thereof.
When the head holder 1 is attached, the head holder 3 protrudes above the upper ends of the ribbon drive cam 33 and the support piece 44.
After fitting the upper end of 6 into the recess 46, the support piece 44
The ribbon cassette 41 is hooked onto the support 42 by means of the above-described structure.

A cylindrical take-up spool 47 and a supply spool 48 are rotatably assembled on both left and right sides of the case body 45, and the ribbon drive cam 3 is located in the hollow portion of the take-up spool 47 located on the left side.
3 is formed with a removable engaging claw 47a.
A thermal transfer ribbon 49 made of a synthetic resin tape coated with ink is wound around the outer periphery of both spools 47 and 48, and as the take-up spool 47 rotates, the thermal transfer ribbon 49 on the supply spool 48 side 49 is adapted to be wound onto the take-up spool 47 side. Further, a substantially V-shaped planar holding spring 50 whose base end is fixed on the front bottom plate of the case body 45 is interposed between the spools 47 and 48.
The outer surfaces of both ends of the thermal transfer ribbon 49 are pressed against the outermost ribbon 49 wound around the spools 47 and 48, so that the spools 47 and 48 do not move loose due to vibration or the like and the thermal transfer ribbon 49 does not loosen. Note that 40 in FIG. 1 is a manual operation knob attached to the top of the take-up spool 47.

On the other hand, an exit opening 51 for the thermal transfer ribbon 49 is formed at a position adjacent to the right side of the recess 46 on the rear outer circumferential surface of the case body 45, and at the rear end on the left outer circumferential surface of the case body 45. An entrance opening 52 is formed in the section, and a portion of the thermal transfer ribbon 49 is exposed to the outside of the case body 45 between the openings 51 and 52, and the thermal transfer ribbon 49 is inserted between the printing paper P and the thermal printing head 37. is held between. When a predetermined print signal is output, the heating element of the thermal print head 37 is selectively heated, and the heat melts the ink on the corresponding portion of the thermal transfer ribbon 49, and the ink is transferred onto the print paper P. Predetermined characters, etc. are printed.

Further, a guide portion 53 is formed in the case body 45 from the outlet opening 51 toward the supply spool 48, and the ribbon 49 led out from the supply spool 48 along the upper surface of the guide portion 53 is guided to the outlet opening 5.
You will be guided to 1. A leaf spring 55 as an elastic member is engaged with a support pin 54 erected at a position close to the inner surface of the case body 45 in the vicinity of the guide portion 53 , and a portion of its proximal bent portion 56 is engaged with a support pin 54 . It is held between the support pin 54 and the inner surface of the case body 45. A pressing piece 57 made of felt is attached to the front surface of the tip of this leaf spring 55, and this pressing piece 57 always presses the thermal transfer ribbon 49 against the rear side of the guide part 53 by the spring force of the leaf spring 55, and heats it. A certain tension is applied to the thermal transfer ribbon 49 supplied to the printing head 37 side.

Next, the feeding operation of the thermal transfer ribbon 49 in the thermal transfer printer configured as above will be explained.

Now, as shown in FIGS. 2 and 4, with the thermal transfer ribbon 49 sandwiched between the front surface of the thermal printing head 37 and the printing paper P on the second surface of the platen, as the carrier 14 performs printing operations, When moving to the right, the thermal transfer ribbon 49 is moved relative to the carrier 14 together with the printing paper P while sliding on the surface of the thermal printing head 37 due to friction with the printing paper P. The unprinted thermal transfer ribbon 49 is then unwound from the supply spool 48 of the ribbon cassette 41 and supplied to the thermal print head 37 through the outlet opening 51. As the carrier 14 moves, the engagement gear 24 that meshes with the rack 16 of the paper guide table 4 is rotated, and as shown in FIG. 29 and the camshaft 32 to the ribbon drive cam 33. When the drive cam 33 rotates, the take-up spool 47 of the ribbon cassette 41 is rotated as shown in FIG.
Used thermal transfer ribbon 49 is sequentially wound onto its take-up spool 47 through inlet opening 52 .

In this case, the actual feeding of the thermal transfer ribbon 49 is not by the rotation of the take-up spool 47;
Since this is performed by moving the carrier 14 relative to the ribbon 49, the amount of movement of the ribbon 49 is always the same as the amount of movement of the carrier 14, that is, the relative movement amount of the printing paper P, and the ribbon 49 is moved by the width of the printed character. can be sent. Therefore, there is no risk that the ink surface of the ribbon 49 may slip while in contact with the printing paper P, thereby staining the surface of the printing paper P.

By the way, the number of revolutions of the take-up spool 47 that performs fixed amount winding is reduced as the winding diameter of the ribbon 49 increases, while the ribbon drive gear 29 is rotated due to the movement of the carrier 14. It rotates at a constant speed. In this embodiment, the camshaft 32, which rotates integrally with the take-up spool 47 via the ribbon drive cam 33, is interlocked with the ribbon drive gear 29 by the clutch plate 34 so as to be able to slide and rotate relative to each other. The take-up spool 4 remains undecelerated.
There is no possibility that excessive tension will be transmitted to the 7 side and act on the ribbon 49. Therefore, the take-up spool 47
Regardless of the diameter of the thermal transfer ribbon wound on the thermal transfer ribbon 49, a constant tension is applied to the thermal transfer ribbon 49.
can be wound up.

After completing the printing activity for one printing line, the solenoid 9 is energized based on the carrier return signal, the solenoid lever 11 is attracted and swung, and the head release plate 7 is pushed down.
Therefore, the carrier 14 is tilted around the guide rod 5 to the release position, and the carrier 14 is tilted to the release position.
The upper thermal printing head 37 is released from the printing paper P together with the thermal transfer ribbon 49, and the engagement gear 24 and the rack 16 of the paper guide table 4 are disengaged. Thereafter, the carrier 14 is returned to the left. During this return operation, engagement gear 2
4 is not rotated, the thermal transfer ribbon 49 is not fed. Furthermore, the carrier 14 is tilted to the release position by the backspace signal or the tab signal, so the thermal transfer ribbon 49 is not fed.

As described above, in the thermal transfer printer of this embodiment, when the ribbon cassette 41 is mounted on the support base 42 of the carrier 1, the recess 46 of the ribbon cassette 41 is aligned with the head holder 36, and the head holder 3
The ribbon cassette 41 can be attached by simply pushing down the ribbon cassette 41 using the head holder 6 as a guide, and it is also possible to form a hooking member on the head holder 36 itself for hooking the ribbon cassette.

〔effect〕

As detailed above, in this invention, the head holder is used as a guide for the ribbon cassette, so the operator only needs to pay attention to the fit between the exposed part of the thermal transfer ribbon or the recess in the cassette and the head holder.
It is possible to provide a thermal transfer printer in which the ribbon cassette mounting operation is extremely easy.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a thermal transfer printer showing an embodiment of this invention, Fig. 2 is a partially cutaway side view of the carrier, Fig. 3 is a partially cutaway plan view of the carrier, and Fig. 4 is a ribbon FIG. 3 is a cross-sectional view of the cassette. In the diagram, platen 2, carrier 14, rack 1
6, head holder 36, engagement gear 24, thermal printing head 37, ribbon cassette 41, recess 46, take-up spool 47, supply spool 48, thermal transfer ribbon 49, outlet opening 51, guide portion 53, leaf spring 5
It is 5.

Claims (1)

[Claims for Utility Model Registration] A carrier movable along the printing lines of a printing paper made of plain paper supported on a paper support device, and teeth provided on a printer body parallel to the moving direction of the carrier. a head holder supported to be movable between a printing position and a release position with respect to the carrier and fixing a thermal printing head; and a gear on the carrier that is engageable with the toothed member. a support member that rotatably supports the gear; and the support member is always biased so that the gear engages with the toothed member, and when the head holder is moved to the release position, the gear and the toothed member are biased. a drive cam operatively connected to the gear; a slip clutch interposed between the gear and the drive cam; and a slip clutch for winding the thermal transfer ribbon. a ribbon cassette having a supply spool and a take-up spool capable of winding up the thermal transfer ribbon supplied from the supply spool between the thermal print head and the printing paper and being engageable with the drive cam; and the thermal transfer ribbon of the ribbon cassette. a recess formed on the carrier and having a width slightly greater than the width of the head holder; and at least two supports formed on the carrier for latching the ribbon cassette. and the upper end of the head holder is configured to be higher than the drive cam and the upper end of the support member, so that when the ribbon cassette is installed, the ribbon cassette is guided onto the carrier using the head holder as a guide and is fixed by the support member. A thermal transfer printer characterized by: