JP2604634B2 - Thermal transfer recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mechanism for peeling an ink ribbon fed between a recording head and a platen of a thermal transfer recording apparatus from a platen.

<Prior art> Conventionally, a thermal transfer type recording device used in a printer or the like presses a recording head through an ink ribbon against a recording paper wound around a platen, and prints a heating element on the recording head. It is driven based on a pattern signal, heats and melts the ink on the ink ribbon, and transfers it to recording paper to perform printing. Then, in order to obtain good print quality, after transferring to the recording paper, the ink ribbon is peeled off from the platen at a peeling angle according to the type of the ink ribbon or the printing speed on the downstream side of the recording head in the scanning direction of the ink ribbon. Go.

FIGS. 11 (a) and (b) and FIGS. 12 (a) and (b) show the outline of the peeling mechanism. The peeling mechanism is
A peeling lever 4 is provided rotatably around a rotation axis 5 on the downstream side of the recording head 3 arranged in the ink ribbon scanning direction with respect to the platen 1 with the ink ribbon 2 interposed therebetween. And a switching lever 6 for switching the position of the peeling lever 4 accordingly.

The switching lever 6 is supported so as to be movable up and down on a support shaft 6a and is urged upward by a compression spring 7, so that the switching lever 6 comes into contact with the peeling lever 4 in the upper position to suppress the rotation of the peeling lever 4. Are arranged. Then, the type of the ink ribbon 2 is determined by entering and leaving the hole 9 of the ribbon cassette 8 of the ink ribbon 2.

That is, as shown in FIG. 11 (a), when there is no hole 9 in the ribbon cassette 8, the switching lever 6 is turned on.
11 and is not in contact with the peeling lever 4, the peeling lever 4 becomes rotatable and contacts the ink ribbon 2 at a position away from the platen 1 as shown in FIG. 11 (b). The peel angle θ is increased. On the other hand, as shown in FIG.
, The switching lever 6 is inserted into the hole 9 by the urging force of the compression spring 7 and is at the upper position. At this time, the rotation of the peeling lever 4 is suppressed by the switching lever 6, and as shown in FIG. 12 (b), the peeling lever 4 comes into contact with the ink ribbon 2 at a position close to the platen 1 to reduce the peeling angle θ.

<Problems to be Solved by the Invention> However, in the above-mentioned prior art, since the peeling angle θ of the ink ribbon is mechanically switched depending on the presence or absence of the hole 9 in the ribbon cassette 8, only two kinds of peeling angles θ are set. No, it cannot respond to printing speed.

Further, in the case of a multi-color thermal transfer recording apparatus such as a color printer, the ribbon cassettes are stacked in multiple stages, and there is a problem that the presence or absence of the holes in the upper ribbon cassette cannot be detected.

Moreover, the positioning of the peeling lever 4 during the operation is
Since it is determined by the dimensions and the mounting accuracy of the peeling lever 4, the positioning accuracy varies greatly, and a constant peeling angle cannot be obtained. Therefore, when the peeling angle is too small, the ink is hardly transferred to the recording paper, and the dropout increases. On the other hand, if the peeling angle is too large, the ink on the ink ribbon is transferred while being cooled and solidified, and the fixability of the ink is reduced, resulting in blurred printing. As described above, there is a problem that the print quality cannot be kept constant due to the variation of the peeling angle.

In view of the above, an object of the present invention is to provide a thermal transfer recording apparatus that can set a peeling angle in accordance with the type of an ink ribbon or a printing speed, and that can obtain good print quality without variation in the peeling angle. And

<Means for Solving the Problem> The means for solving the problem according to claim 1 of the present invention is shown in FIGS.
As shown in the drawing, a recording head 11 is disposed so as to be able to freely contact and separate from the platen 31 with the ink ribbon 15 interposed therebetween, and the ink ribbon 15 disposed downstream of the recording head 11 in the scanning direction of the ink ribbon 15 is peeled off the platen 31. And a peeling angle variable cam 34 for changing the peeling angle θ of the ink ribbon 15 with respect to the platen 31 when the recording head 11 is pressed against the platen 31. A follower 35 that is driven by the variable peel angle cam 34 is formed, and a positioning means 36 for preventing a displacement of the peeling member 33 with respect to the recording head 11 is provided.

A head separation cam 32 for separating the recording head 11 from the platen 31 is rotatably provided on the carriage 12 on which the recording head 11 is mounted.
Numeral 34 is formed integrally on the outer peripheral surface of the head separation / contact cam 32.

<Operation> In the means for solving the above problems, the head detachment cam 32 is rotated by the recording command, the recording head 11 is pressed in the direction of the platen 31, and the ink on the ink ribbon 15 is melted and thermally transferred to the paper.

At this time, the peeling angle variable cam 34 is rotated together with the rotation of the head separation / contact cam 32, and the amount of rotation is controlled according to the type of the ink ribbon 15 or the printing speed. Here, the follower 35 changes the position of the peeling member 33 with respect to the recording head 11 according to the amount of rotation. When the position of the peeling member 33 changes, the peeling member 33 comes into contact with or separated from the ink ribbon 15, and the peeling angle θ of the ink ribbon 15 with respect to the platen 31 is changed.

Then, when the recording is completed, the head separating / contacting cam 32 and the peeling angle variable cam 34 rotate, the recording head 11 is separated from the platen 31, and the peeling member 33 is separated from the ink ribbon 15. Then, the apparatus enters a standby state for the next recording.

Accordingly, since the peeling angle of the ink ribbon 15 from the platen 31 can be changed, the ink ribbon 15
The optimum peeling angle can be set according to the 15 types or the printing speed, so that the optimum printing conditions can be obtained, and good printing quality can be obtained.

In addition, when the peeling member 33 is positioned with respect to the recording head 11 by the positioning means 36 during the operation of the peeling member 33, the deviation in positioning can be eliminated, and the peeling angle can be set accurately.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a side view of a peeling mechanism of a thermal transfer recording apparatus according to a first embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a perspective view thereof, and FIG. FIG. 5 is a plan view showing the relationship between the peeling mechanism and the ribbon cassette, FIG. 5 is a perspective view of the thermal transfer recording apparatus, FIG. 6 is a perspective view of the carriage of the thermal transfer recording apparatus, and FIG. 7 shows the change of the peeling angle of the ink ribbon. FIG. 8 is a diagram showing the relationship between the recording head and the displacement of the peeling member.

As shown in FIGS. 5 and 6, the multi-color thermal transfer recording apparatus according to the present invention includes a carriage in which a recording head 11 is mounted on a thermal transfer recording apparatus main body 10 and reciprocates in a scanning direction orthogonal to a paper feeding direction.
A cassette table 14 on which a plurality of ink ribbon cassettes 13 of yellow, magenta, cyan and the like are superimposed and placed above the carriage 12; and the plurality of ink ribbon cassettes 13 during scanning of the recording head 11 a plurality of times. And a lifting device 16 for raising and lowering the cassette table 14 with respect to the carriage 12 so as to sequentially select the ink ribbons 15 and face the recording head 11.

As shown in FIG. 6, a driving device 17 for moving the carriage 12 in the scanning direction includes a pair of left and right pulley gears 18 arranged at both ends in the scanning direction, and a front portion of the carriage 12 wound around the pulley gear 18. And a scanning motor 20 for driving the pulley gear 18 to rotate.

The carriage 12 has a first paper guide plate 21 and a second paper guide plate 22 on both left and right sides of the recording head 11. The first paper guide plate 21 is fixed to the carriage 12 with its upper end curved toward the platen (front side) in order to prevent the printed paper from being bent toward the recording head 11 side.

The second paper guide plate 22 is for preventing the recording head 11 from breaking toward the recording head 11 and preventing the paper from bulging during printing. The upper end side is curved toward the platen (front side), and the side end on the printing direction side is formed. It is curved in the platen direction (front side) and is fixed to the carriage 12.

A take-up reel 23 is rotatably supported by the carriage 12 so as to penetrate the cassette table 14 behind the recording head 11. The rotation drive mechanism of the take-up reel 23 is a sixth drive mechanism.
As shown in the figure, a rack 24 arranged in the scanning direction on the rear side of the carriage 12 meshes with the rack 24 in accordance with the rotation of the recording head 11 and rotates in accordance with the movement of the carriage 12, and this rotational force is taken up by the take-up reel 23. And a pinion (not shown) for transmission to the motor.

Further, a ribbon sensor 25 is provided at a front portion of the carriage 12. This ribbon sensor 25 includes a color ribbon,
It detects the end (end) of the black ribbon and comprises an optical coupling device. The detection result of the ribbon sensor 25 is displayed on the display unit, whereby it is possible to confirm whether the print mode matches the attached ribbon or not, and to notify the end of the ribbon.

The second paper guide plate 22 faces the ribbon sensor 25.
Is provided with a reflection plate 26. Based on the optical signal reflected from the reflection plate 26 to the ribbon sensor 25, for example, the distinction between the color ribbon and the black ribbon is made based on the high-level (color) and low-level (black) signals of the reflected light. The ribbon end is determined by a signal from the stripe pattern of the ink ribbon 15.

As shown in FIG. 6, the ink ribbon cassette base 14 is of an open top type surrounded by side walls. In this embodiment, three different color ink ribbon cassettes 13 are superposed on the cassette base. On the opposite side of the cassette table 14 from the ink ribbon 15, there is provided a cassette presser 27 having elasticity and preventing the ink ribbon cassette 13 from moving.

In the figure, reference numeral 28 denotes a feed roller, 29 denotes a motor for driving the feed roller 28 to rotate, and 30 denotes a guide rod for guiding the carriage 12 in the scanning direction.

The peeling mechanism of the thermal transfer recording apparatus includes, as shown in FIGS. 1 to 3, a recording head 11 which is disposed so as to be able to freely contact and separate the platen 31 with the ink ribbon 15 interposed therebetween, and the recording head 11 is attached to the platen 31. A head detachable cam 32 movable with respect to the recording head 11, and a peeling member 33 disposed downstream of the recording head 11 in the scanning direction of the ink ribbon 15 to separate the ink ribbon 15 from the platen 31. When the peeling angle variable cam 34 for changing the peeling angle θ of the ink ribbon 15 with respect to the platen 31 is
32 is arranged in parallel with the peeling member 33,
A driven body 35 driven by the driven body 35 is formed.

The platen 31 is a cylindrical roller, is rotatably supported by a line feed means (not shown) on the thermal transfer recording apparatus main body 10 at intervals, and the sheet fed by the feed roller 28 is wound around the outer peripheral surface. .

The recording head 11 is a thermal head, and includes a head substrate 37 made of aluminum or the like, and a heating resistor element 38 formed on the front surface of the head substrate 37 on the platen 31 side.

As shown in FIG. 3, the head substrate 37 is formed in a hook shape, and its base 37a is swingably supported by the carriage 12 via a support shaft 39.

The head detaching cam 32 is a disc-shaped cam supported on the carriage 12 via a rotary shaft 40, and has a recording head on its upper surface.
An ascending portion 32a for bringing the recording head 11 into a printing state close to the platen 31 and a descending portion 32b for keeping the recording head 11 in a moving state of the recording head 11 separated from the platen 31 are formed.

A receiving plate 41 for separating the head substrate 37 from the platen 31 according to the rotation of the head separating cam 32 is in contact with the upper surface of the head separating cam 32. It is swingably supported by 39 and is pressed against the head substrate 37 by a spring 42. When the recording head 11 is moved to the base 37a of the head substrate 37, the recording head 11 is placed on the platen 31.
A coil spring 43 for attaching the coil spring 43 is attached.

The peeling member 33 is formed in an L shape and is swingably supported by a support shaft 39. The upper portion of the peeling member 33 comes into contact with the ink ribbon 15, and a leg as the follower 35 projects from the lower portion.

The variable peeling angle cam 34 is a head separating cam.
32 are provided integrally on the outer peripheral surface. In a region on the upper surface corresponding to the rising portion 32a of the head separating / contacting cam 32, a low step portion 34a, a middle step portion 34b, and a high step portion 34c are sequentially formed along the rotation direction. And the peeling angle variable cam
A tooth 44 is engraved on the outer peripheral surface of the gear 34, and the tooth 44 is connected to a driving gear 45a of a driving motor 45 mounted on the carriage 12 via a double gear 46, and the head separating cam 32 and the pulling The peel angle variable cam 34 rotates integrally.

A driven member 35 of a peeling member 33 is in contact with the upper surface of the peeling angle variable cam 34, and the inclination of the peeling member 33 is changed according to the rotation of the head detaching cam 32 to position the recording head 11. And the relative position of the peeling member 33 is changed. Then, the drive motor 45 is controlled so as to rotate the head detachment cam 32 so that the peeling angle variable cam 34 is at a relative position where an optimum peeling angle can be obtained according to the type of the ink ribbon 15 and the printing speed. ing.

In addition, as shown in FIG.
From 47, the ink is guided to the recording head 11 through an ink ribbon outlet 49 via guide pins 48a, 48b and 48c. Then, the recording head 11 passes through the ink ribbon entrance 50 and the guide pin 48d.
Is wound up on the winding roller 51 via the. At this time, the scanning path of the ink ribbon 15 is determined by the recording head 11 and the ink ribbon entrance 50, and the peeling member 33 moves in the direction of the platen 31 between the recording head 11 and the ink ribbon entrance 50. As a result, the angle at which the ink ribbon 15 is peeled off from the platen 31 is switched.

In the above configuration, the carriage 12 is started by the recording command, the drive motor 45 is operated, and the head detachment cam 32 is operated.
Rotates. Then, as the head detachment cam 32 rotates, the receiving plate 41 is driven from the descending portion 32b along the rising portion 32a, and presses the head substrate 37 in the direction of the platen 31. Then, the ink of the ink ribbon 15 is melted by the heating resistor element 38 and thermally transferred to the paper.

At this time, the peeling angle variable cam 34 is also rotating together with the rotation of the head detachment cam 32, the drive motor 45 is driven according to the type of the ink ribbon 15 or the printing speed, and the driven body 35 is moved to the low step portion 34a, It is rotated until it comes into contact with either the middle section 34b or the high section 34c. Here, the state A shown in the seventh and eighth figure when the follower 35 is in contact with the low-stage unit 34a, the peeling member 33 is not not peel angle against the ink ribbon 15 becomes theta _1. Similarly, the state B is when the driven body 35 abuts on the middle portion 34b, and the peeling member 33 is
And the peeling angle becomes θ ₂ . State C is follower 3
5 comes into contact with the high step portion 34c,
The peel angle closest to 31 is θ ₃ , and θ ₁ > θ ₂ >
θ ₃ and a three-step peeling angle can be selected.

Then, when the recording is completed, the head separation / contact cam 32 and the detachable angle variable cam 34 rotate, and the receiving plate 41
b, the recording head 11 is separated from the platen 31, the driven member 35 is also contacted with the low step portion 34a, the release member 33 is separated from the ink ribbon 15, and the ink ribbon 15 is moved. Is wound on the take-up reel 23, and the apparatus enters a standby state for the next recording.

Accordingly, since the peeling angle of the ink ribbon 15 from the platen 31 can be changed, the ink ribbon 15
The optimum peeling angle can be set according to the 15 types or the printing speed, so that the optimum printing conditions can be obtained, and good printing quality can be obtained.

[Second embodiment] Fig. 9 is a side view of a peeling mechanism showing a second embodiment of the present invention, and Fig. 10 is a front view thereof.

In the recording head 11 of the present embodiment, the head substrate 37 is formed in an L-shape, and the legs 52 projecting from the head substrate 37 are in contact with the head separation cam 32. In addition, the follower 35 of the peeling member 33
Is made of a leaf spring, and the dispersion of the variable peel angle cam 34 and the dispersion of the peeling member 33 are to be absorbed by the leaf spring.

Further, a positioning means 36 is provided for preventing a displacement of the peeling member 33 with respect to the recording head 11 and eliminating a variation in positioning.

The positioning means 36 includes a projection 36a protruding from an upper side surface of the head substrate 37 on the side of the peeling member 33, and a concave portion 36b formed on an upper front surface of the peeling member 33 on the side of the platen 31. Abuts on the concave portion 36b to maintain the positioning accuracy during the operation of the peeling member 33.

Other configurations are the same as those of the first embodiment, and have the same operation and effect.

Then, by positioning the peeling member 33 at the time of operation by the positioning means 36, it is possible to eliminate the variation in the positioning and to set the peeling angle with high accuracy.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention.

For example, the head separating / contacting cam 32 and the variable peeling angle cam 34 are not limited to disk-shaped ones, but may be those having irregularities on the outer peripheral surface of a cylinder.

Further, by providing peeling members 33 on both sides of the recording head 11, the present invention may be applied to a thermal transfer recording apparatus capable of reciprocal printing.

The positioning means 36 may be one in which a projection is provided on the peeling member 33 and a concave portion is provided on the recording head 11.

<Effects of the Invention> As is clear from the above description, according to the first aspect of the present invention, a recording head arranged so as to be detachable from the platen with the ink ribbon interposed therebetween, and a downstream side of the recording head in the ink ribbon scanning direction. A peeling member for changing the peeling angle of the ink ribbon to the platen when the recording head is pressed against the platen, the peeling member being provided with a peeling angle variable cam. Since a follower that is driven by the variable peel angle cam is formed, the peel angle of the ink ribbon from the platen can be changed, and the optimum peel angle can be changed according to the type of ink ribbon or printing speed. The printing conditions can be set, the printing conditions become optimal, and good printing quality can be obtained.

Further, since the positioning means for preventing the displacement of the peeling member with respect to the recording head is provided, it is possible to eliminate the variation in the positioning during the operation of the peeling member,
The peeling angle can be accurately set.

A head separation / separation cam for separating the recording head from the platen is rotatably provided on a carriage on which the recording head is mounted, and a detachable angle variable cam is integrally formed on the outer peripheral surface of the head separation / contact cam. Therefore, the recording head and the peeling member can be linked with one cam,
Accurate drive control of both can be performed, and the print quality can be improved. Moreover, since the number of parts can be reduced, the arrangement space can be minimized, and the space on the carriage can be effectively utilized.

[Brief description of the drawings]

FIG. 1 is a side view of a thermal transfer recording and peeling mechanism of an apparatus showing a first embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a perspective view thereof, and FIG. 4 is a peeling mechanism and ribbon. FIG. 5 is a perspective view of the thermal transfer recording apparatus, FIG. 6 is a perspective view of a carriage of the thermal transfer recording apparatus, FIG. 7 is a view showing a change in the peeling angle of the ink ribbon, FIG. FIG. 9 is a diagram showing the relationship between the recording head and the displacement of the peeling member, FIG. 9 is a side view of a peeling mechanism showing a second embodiment of the present invention, FIG. 10 is a front view thereof, and FIG. FIG. 12B is a front view of the conventional peeling mechanism when the peeling angle is large, FIG. 12B is a plan view thereof, and FIG. 12A is a front view of the peeling mechanism when the peeling angle is small. FIG. 2B is a plan view thereof. 11: recording head, 15: ink ribbon, 31: platen, 33: peeling member, 34: peeling angle variable cam, 35: follower, 36: positioning means.

Claims (2)

(57) [Claims] A recording head disposed so as to be able to freely contact and separate from the platen with an ink ribbon interposed therebetween; and a peeling member disposed downstream of the recording head in the ink ribbon scanning direction to peel off the ink ribbon from the platen. When the recording head is pressed against the platen, a peeling angle variable cam for changing the peeling angle of the ink ribbon with respect to the platen is provided, and a follower which follows the peeling angle variable cam is formed on the peeling member. And a positioning device for preventing a displacement of the peeling member with respect to the recording head. 2. A head detaching cam for detaching a recording head from a platen is rotatably provided on a carriage on which the recording head is mounted, and a variable peel angle cam is integrally formed on an outer peripheral surface of the head detaching cam. 2. The thermal transfer recording apparatus according to claim 1, wherein the thermal transfer recording apparatus is formed in a uniform manner.