JPH0647305B2 - Thermal transfer recorder - Google Patents

Description

The present invention relates to a thermal transfer recording device.

(B) Conventional technology Thermal transfer in which an ink sheet and recording paper are superposedly inserted between the pressure contact between the thermal head and the platen, and the thermal head is driven while conveying them in the same direction to perform recording on the recording paper. The recording device has already been put to practical use, for example, as disclosed in Japanese Patent Application Laid-Open No. 58-140266.

In such a thermal transfer recording apparatus, it is desirable that the conveyance speeds of the ink sheet and the recording paper are exactly the same.

(C) Problems to be Solved by the Invention By the way, since the ink sheet and the recording sheet are generally conveyed by a conveying roller provided with a rotational driving force of a driving motor from a transmission gear or a belt, respectively. In view of these mechanical precisions, it is very difficult to make the conveyance speeds of the ink sheet and the recording paper completely the same.

Therefore, considering the case where the recording sheet is larger than the conveying speed of the ink sheet, since the ink sheet is generally a very thin film, the ink sheet moves as the recording sheet moves. Is dragged at a speed higher than its own transport speed, that is, the recording paper moving speed. When the ink sheet is dragged and advanced in this manner, the speed of the ink sheet does not follow the transport speed of the ink sheet itself, causing slack in the ink sheet and further causing wrinkles, which causes defective recording.

Therefore, it is an object of the present invention to convey an ink sheet and a recording paper without particularly requiring a high degree of mechanical precision and further suppressing the occurrence of wrinkles and slack of the ink sheet.

(D) Means for Solving the Problems The present invention is to insert an ink sheet and a recording sheet in an overlapping manner between a thermal head and a platen, and convey them in the same direction while transferring ink on the ink sheet. In the thermal transfer recording apparatus for transferring the recording sheet onto a recording sheet to perform recording, the conveying speed of the ink sheet is set to be higher than the conveying speed of the recording sheet.

(E) Action According to the present invention, since the ink sheet conveyance speed is set to be higher than the recording paper conveyance speed within a certain range, the ink sheet is conveyed prior to the recording paper, which is different from the conventional case. ,
It will not be dragged as the recording paper is conveyed.

In this case, the recording paper is dragged along with the conveyance of the ink sheet, but since the recording paper has a certain degree of rigidity, the recording paper is not dragged and moved.

(F) Embodiment FIG. 1 is a side view showing a thermal transfer recording apparatus for performing color recording to which an embodiment of the present invention is applied.

Ink sheet pulled out from the ink sheet roll (1)
(2) has, for example, yellow, magenta, cyan, and black color inks repeatedly in the longitudinal direction in this order, and the thermal head (via the guide shaft (3) and the first head guide shaft (4) 5) Passes through the contact between the rotatable platen (6), the second head guide shaft (7), the contact between the conveying roller (8) and the pressure contact roller (9), and the guide shaft (10). To the winding roll (11).

On the other hand, the recording paper (13) pulled out from the recording paper roll (12) mounted between the pair of holding reels (50) is the guide roller (1
4), the two plates are inserted from the insertion opening (15a) of the insertion path (15) provided with a slight gap, and the first conveyance roller (1
6) and the first pressure contact roller (17), and then the thermal head (5) through the gap between the platen (6) and the guide roller (18) arranged very close to and facing the platen (6). ) And the platen (6) and the second conveying roller (19) and the second pressure roller (20). To the discharge port (21a) of the discharge path (21).

The thermal head (5) is disposed on the pair of plate-shaped brackets (30) and can be brought into and out of contact with the platen (6).

The plate-shaped bracket (30) has a substantially V-shape composed of a first branch portion (31) and a second branch portion (32), and a coupling portion of each branch portion is rotatably supported by a shaft (33). It is supported. The first branch portion (31) has a thermal head (5), a first head guide shaft (4) and a second head.
The head guide shafts (7) are arranged parallel to each other, and
A cam pressure contact shaft (35) having a cam pressure contact roller (34) is arranged on the branch portion (32). Also, the plate bracket (30)
Is urged to rotate clockwise about the shaft (33) by a spring (37) stretched between the tip of the second branch portion (32) and the shaft (36).

The cam support shaft (39) having the fan-shaped eccentric cam (38),
The cam pressure contact roller (34) and the eccentric cam (38) are arranged above the cam pressure contact shaft (35) in parallel with this shaft.

Then, the cam support shaft (39) is appropriately rotated by a drive motor (not shown), so that the thermal head (5)
Is moved toward and away from the platen (6). That is, the eccentric cam (3
When 8) is positioned above the cam support shaft (39), plate bracket (30) causes spring (37) to rotate shaft (33).
The thermal head (5) is urged to rotate clockwise around
Presses against the platen (6). On the other hand, when the eccentric cam (38) is positioned below the cam support shaft (39), the eccentric cam (38) pushes down the cam pressure contact shaft (35), thus
The plate bracket (30) rotates counterclockwise around the shaft (33) against the biasing force of the spring (37), and
(5) is separated from the platen (6).

In the middle of the conveyance path of the ink sheet (2), the ink sheet
The light source (40) and the color sensor (46) are arranged so as to face each other with (2) interposed therebetween, and the color of the ink sheet (2) is detected.

FIG. 4 is a side sectional view showing the mounting portion of such a light source (40). The light source (40) is screwed into the base (41) and planted. The cylindrical cover (43) is formed slightly higher than the light source (40), and its inner diameter is substantially equal to the maximum diameter of the light source (40). The cover (43) is attached so as to surround the light source (40). A guide groove (44) is formed on the outer wall of the cover (43) from the lower end to substantially the center, and the guide groove (4
There is a hole (45) at the end of 4). The leaf spring (42) with its tip protruding in a V shape toward the light source (40) and bent is such that the distance between the tip of the V-shaped portion and the outer periphery of the light source (40) is greater than the thickness of the cover (43). The light source (40) is arranged side by side in a narrowed arrangement and substantially parallel to the light source (40). Therefore, when the position of the guide groove (44) of the cover (43) is aligned with the leaf spring (42) and the cover (43) is lowered, the cover (43) is guided by the leaf spring (42) and moves downward. The cover (43) is sandwiched and fixed by the leaf spring (42) and the light source (40) by engaging the tip of the dog-legged portion of the leaf spring (42) in the hole (45).

In addition, the upper end opening of the cover (43) is, as shown in FIG.
Since it is oblique and is arranged so as to be close to and in parallel with the surface of the ink sheet (2), the cover (4
If the mounting direction of 3) is improper, the upper end of the cover (43) may contact the ink sheet (2) and damage the ink sheet (2). However, according to the present invention, by aligning the guide groove (44) of the cover (43) with the leaf spring (42), the tip of the cover (43) can be securely attached to the ink sheet.
It is installed so that it is almost parallel to (2).

Therefore, the light source (40) does not come into contact with the ink sheet (2) to be contaminated, and the ink sheet (2) does not deteriorate due to heat generated when the light source (40) is turned on. Further, since the cover (43) can be easily pulled out upward, the light source (40) can be easily replaced.

Each of the above parts is a pair of fixed side plates (100) and slightly inward of these fixed side plates and parallel to them, and the shaft (10
It is attached to a pair of movable side plates (102) rotatably arranged around (1).

Ink sheet roll is placed between the pair of fixed side plates (100).
(1), a guide shaft (3), a thermal head (5) and its peripheral part, a conveying roller (8), a guide shaft (10) and a winding roll (11) are attached.

Between the pair of movable side plates (102), the recording paper roll (12), the guide roller (14), the first transport roller (16), and the first pressure contact roller (1
7), platen (6), pinch roller (18), second transport roller
(19) and the second pressure contact roller (20) are attached.

2 and 3 are perspective views showing the main part of the transport drive system for the recording paper (13). FIG. 2 shows the right movable side plate (102) from the outside, and FIG. 3 shows the left side. The movable side plate (102) is shown from the outside.

First, in FIG. 2, the shaft (101) is rotated by a drive motor (not shown), and the shaft (101) is provided with a gear pulley (200).
A gear belt (202) is stretched between and the gear pulley (201) supported by the movable side plate (102). The gear (203) formed integrally with the gear pulley (201) is usually a transmission gear (204) (20
5) is connected to the gear (206) arranged on the rotary shaft of the first conveying roller (16), and when the shaft (200) is rotated clockwise in the figure, the first conveying roller (16) 16) It is rotated counterclockwise in the figure at a certain rotation speed.

The arm (207) supporting the gears (204) (205) has one end (20)
It is rotatably supported by 8) and the other end is connected to a solenoid (209). A pulling force is applied to the other end by a spring (210). Therefore, the solenoid (2
If (09) is de-energized, the transmission gear (205) will turn into gear (206).
And the solenoid (209) is energized, the arm (20
7) rotates clockwise against the force of the spring (210), and the transmission gear (205) separates from the gear (206).

Since the slip clutch (211) is fixed to the rotation shaft of the second conveying roller (19), the second conveying roller (19) can smoothly rotate clockwise in the figure, and friction braking in the counterclockwise direction in the figure. Can be rotated while being given.

FIG. 5 is a side sectional view showing an embodiment of the slip clutch (211). Bearing (22) fixed to the movable side plate (102)
0) rotatably supports the rotary shaft of the second transport roller (19). The tubular body (221) having a flange at one end is rotatably fitted to the rotary shaft of the second transport roller (19) with the friction sheet (222) sandwiched between the flange and the bearing (220). There is. Further, a spring (224) is provided on the outer periphery of the tubular body (221) between the flange of the tubular body (221) and a nut (223) screwed to the end of the rotation shaft of the second transport roller (19). Are appropriately compressed and interposed, and one end of the spring (224) is locked to the nut (223).

Thus, when the second transport roller (19) rotates clockwise in FIG. 3, the spring (224) is in a loosening direction, and the second transport roller (19) can rotate smoothly. On the other hand, when the second transport roller (19) rotates counterclockwise in FIG. 3, the spring (224) tightens the tubular body (221), and therefore the friction force of the friction sheet (222) is applied to the tubular body. It is transmitted to the rotating shaft of the second carrying roller (19) through the (221) and the spring (224), and the second carrying roller (19) can rotate while receiving friction control copper.

Again in FIG. 2, the holding reel (50) holding one end of the recording paper roll is fixed to the movable side plate (102).

On the other hand, in FIG. 3, the shaft (101) is provided with a gear pulley (300).
A gear belt (302) is stretched around a gear pulley (301) rotatably arranged on the rotary shaft of the conveying roller (19). Further, a gear belt (304) is stretched between a gear pulley (not shown) integrally formed with the gear pulley (301) and the gear pulley (303). Therefore, the rotational force of the shaft (101) is transmitted to the gear pulley (303) via the gear belts (302) (304).

The spring clutch (305) associates the gear pulley (301) with the rotating shaft of the second conveying roller (19), and only when the gear pulley (301) is rotated counterclockwise in the figure, The turning force is transmitted to the rotation shaft of the second transport roller (19) to rotate it.

FIG. 6 is a side sectional view showing in detail the peripheral mechanism of the gear pulley (303).

The gear pulley (303) has a one-way clutch sleeve (310).
The rotating shaft (312) is connected to the outer end portion through (311).
The rotating shaft (312) is rotatably supported by a bearing (314) fixed to the movable side plate (102), and the rotating shaft (312) and the bearing (314) are disposed between the clutch (313). ). Here, the one-way clutch (311) transmits only the counterclockwise rotational force of the sleeve (310) in FIG. 3 to the rotary shaft (312), and the clutch (313) is shown in FIG. 3 of the sleeve (310). Lock the rotary shaft (312) when turning in the clockwise direction.

A reel (315) is fixed near the inner end of the rotary shaft (312), and a holding reel (50) is rotatably fitted through a friction ring (316). The holding reel (50) engages and holds the end of the recording paper roll (12).

The recording operation in such a configuration will be described. In addition,
In the following description, the rotation directions of the ink sheet roll (1), the transport roller (8), the recording paper roll (12), the first transport roller (16), the second transport roller (19), and the shaft (101) are as follows. ,
It shows the direction in FIG.

The recording paper (13) pulled out from the recording paper roll (12) mounted between the holding reels (50) is inserted from the insertion opening (15a) as described above, and the discharge opening (21a) is passed through the predetermined path. ), When the shaft (101) is rotated clockwise by a drive motor (not shown), the first transport roller (16) and the second transport roller (19) move counterclockwise and clockwise, respectively. Is rotated in the direction. Therefore, the recording paper (13) is the recording paper roll (12).
It is pulled out from and conveyed in the forward direction.

At this time, as shown in FIG. 6, the rotating shaft (312) holding the holding reel (50) is in a locked state by the action of the clutch (313), and the holding reel (50) is rubbed by the friction ring (316). It rotates while being given force. Therefore, the recording paper roll (1
An appropriate back tension will be applied to the recording paper (13) pulled out from 2) accurately and surely.
(13) is always pulled out without sagging.

Here, the recording paper (13) is provided between the platen (6) and a pinch roller (18) which is arranged to face the platen with a gap equal to or smaller than the thickness of one recording paper (13). The recording paper (13) is always conveyed in close contact with the outer peripheral surface of the platen (6) because it is guided through the gap between the thermal head (5) and the platen (6). Does not occur. Further, the platen (6) is usually made of an elastic rubber material, but in this embodiment, the pinch roller (18) is not pressed against the platen (6), so that the platen (6) is not deformed. . In this embodiment, the thermal head (5) and the platen (6)
I arranged a pinch roller (18) on the upstream side between the contact with
A pinch roller (18) may be provided on the downstream side between the contacts. Furthermore, it is most effective if it is provided on both the upstream side and the downstream side of the contact.

On the other hand, the ink sheet (2) pulled out from the ink sheet roll (1) and arranged in the above-mentioned predetermined path is the conveyance roller.
By rotating the (8) and the winding roll (11), the recording paper (13) is conveyed in the forward direction between the thermal head (5) and the platen (6).

At this time, the gear ratio and the like are appropriately set so that the transport speed of the ink sheet (2) is about 0 to 5% faster than that of the recording paper (13). Is not dragged when the recording paper (13) is conveyed. here,
Although the recording paper (13) gives a braking force to the conveyance of the ink sheet (2), the ink sheet (2) is strongly pulled in the conveyance direction by the rotation of the winding roll (11). Therefore, the ink sheet (2) will not be loosened and will not be wrinkled.

By the way, according to the present plan, prior to the first thermal transfer recording on the recording paper (13), the recording paper (13) pulled out from the recording paper roll (12) is not subjected to the thermal transfer recording, and the above-mentioned predetermined After being conveyed in the positive direction by a predetermined amount (for example, the length of one color ink of the ink sheet (2)) along the path of
The recording paper (13) is conveyed largely in the reverse direction and then again in the normal direction so that the head of the recording page of the recording paper (13) slightly exceeds the contact distance between the thermal head (5) and the platen (6) or slightly exceeds the contact distance. It is positioned in the right position. At this time, since only the recording paper (13) needs to be conveyed, the thermal head (5) and the platen
(6) can be separated from each other, but is not particularly limited to this, and the recording paper (13) and the ink sheet can be recorded without performing recording with the thermal head (5) and the platen (6) in pressure contact. (2) and (2) may be conveyed in the forward direction, and then both may be conveyed in the opposite directions.

Thus, as described above, the head of the recording page of the recording paper (13) is positioned at a predetermined position, and the first color of the ink sheet (2) pulled out from the ink sheet roll (1).
The recording paper (13) and the ink sheet with the tip of the ink (for example, yellow) positioned at the above-mentioned predetermined position
The first color is recorded on the recording paper (13) by driving the thermal head (5) to generate heat while conveying (2) in the forward direction.

Next, the recording paper (13) is conveyed in the reverse direction in order to perform thermal transfer recording with the second color (for example, magenta) ink of the ink sheet (2).

In this case, first, the eccentric cam (38) is driven and the thermal head (5) is separated from the platen (6).

In this state, when the shaft (101) is rotated counterclockwise, the first conveying roller (16) and the recording paper roll (12) are rotated clockwise and counterclockwise, respectively. Therefore, the recording paper (1
3) is a recording paper roll while being conveyed by the first conveying roller (16)
It is rewound to (12). During this rewinding, the second transport roller
As shown in FIGS. 2 and 5, (19) is subjected to friction braking in the counterclockwise direction by the action of the slip clutch (211) and is rotated along with the movement of the recording paper (13). Therefore, the recording paper (13) is rewound with an appropriate back tension applied, and the rewound recording paper (13) does not have slack or slack. Further, even when a large resistance force is applied to the rewound recording paper (13), the holding reel (50), that is, the recording paper roll (12) is moved by the operation of the friction ring (316) as shown in FIG. The recording paper (13) is normally rewound without tearing because it is configured to slip with respect to the turning force applied from the drive motor (not shown).

In this way, when the rewinding of the recording paper (13) is completed,
(13) is again pulled out from the recording paper roll (12) and conveyed in the forward direction, and the ink next to the ink sheet (2) is thermally transferred.

(G) Effect of the Invention According to the present invention, the ink sheet conveyance speed is set higher than the recording paper conveyance speed. Therefore, the ink sheet is not dragged along with the recording paper conveyance, and therefore the ink sheet is The ink sheet and the recording paper can be conveyed without causing wrinkles or slack.

[Brief description of drawings]

1 to 6 show an embodiment of the present invention, FIG. 1 is a side view showing a thermal transfer recording apparatus, FIG. 2 is a perspective view showing the outside of a movable side plate on the right side, and FIG. 3 is a left side view. FIG. 4 is a perspective view showing the outside of the movable side plate, FIG. 4 is a side sectional view showing a mounting portion of the light source,
FIG. 5 is a sectional view showing the slip clutch portion, and FIG. 6 is a vertical sectional view showing the rotating portion of the recording paper. (1) …… Ink sheet roll, (2) …… Ink sheet,
(5) …… Thermal head, (6) …… Platen, (12) ……
Recording paper roll, (13) …… Recording paper, (18) …… Pinch roller, (40) …… Light source, (43) …… Cover, (50) …… Holding reel, (211) …… Slip clutch, (311) …… One-way clutch, (312) …… Rotating shaft, (313) …… Clutch.

Claims (1)

[Claims] 1. An ink sheet and a recording sheet are superposedly inserted between a thermal head and a platen, and ink is transferred onto the recording sheet while conveying them in the same direction for recording. The thermal transfer recording apparatus is characterized in that the conveying speed of the ink sheet is higher than the conveying speed of the recording paper.