JPH05330179A - Thermal transfer film feed mechanism in thermal transfer printer - Google Patents

Abstract

PURPOSE:To provide a thermal transfer film feed mechanism not stopping the feed of a medium when a thermal transfer film is pressed to the medium and preventing the contamination of the medium. CONSTITUTION:In such a state that the rotation of a taking-up shaft 2 is fixed, a DC motor 19 is rotated to start the taking up of a thermal transfer film 1 on the taking-up shaft 12. Since the taking-up shaft 2 is not rotated, the tension of the thermal transfer film 1 is enhanced and, then, a solenoid 10 is driven to release the fixation of the taking-up shaft 2. By this constitution, the thermal transfer film 1 is pressed to a medium 7 by a thermal head 6 while it runs under tension in synchronous relation to the feed speed of the medium 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer film feeding mechanism in a thermal transfer printer.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a conventional transfer mechanism for a thermal transfer film in a thermal transfer printer. In the figure, 101 is a long belt-shaped thermal transfer film, and 102 is a payout shaft around which an unused portion of the thermal transfer film 101 is wound. Reference numeral 103 is a ratchet wheel mounted coaxially with the payout shaft 102, and a gear-shaped notch 103a is provided on the outer periphery of the ratchet wheel 103.

Reference numeral 104 is a ratchet, 104a is a fulcrum around which the ratchet 104 rotates, and 104b is a stud projectingly formed at one end of the fulcrum 104a.
The notch 103a of the ratchet wheel 103 is provided at the other end with the fulcrum 104a interposed therebetween.
Ratchet 104 is a fulcrum 104
By rotating around a, the claw portion 104c moves in a direction toward and away from the notch 103a of the ratchet wheel 103.

Reference numeral 105 is a stopper for restricting the rotation of the ratchet 104, and the ratchet 104 is the stopper 105.
When the claw portion 104c is rotated to a position where the ratchet wheel 103 abuts on the ratchet wheel 103, the claw portion 104c engages with the notch 103a of the ratchet wheel 103.
Reference numeral 106 denotes a thermal head that performs printing while pressing the thermal transfer film 101 against a medium 107 that is fed along the feeding direction of the thermal transfer film 101 by a mechanism (not shown).
Reference numeral 8 denotes a platen arranged to face the thermal head 106. The thermal transfer film 101 and the medium 107 are sandwiched between the thermal head 106 and the platen 108, and the ink of the thermal transfer film 101 is transferred to the medium 107 by the thermal head 106 to print. I do.

Reference numeral 109 is a head support link, and 109a is a fulcrum about which the head support link 109 rotates.
The thermal head 106 is fixed to one end of the head support link 109 with a fulcrum 109a interposed therebetween, and the head support link 109 rotates around the fulcrum 109a, whereby the thermal head 106 approaches and separates from the platen 108. Move in the direction you want to. 109b is a fulcrum 109a
It is a stud that is formed so as to project from the other end of the head support link 109 while sandwiching it.

Reference numeral 110 is a solenoid for moving the ratchet 104 and the thermal head 106, and 111 is a link attached to the movable core of the solenoid 110. 111
a is a square hole formed in the link 111, and this square hole 111
The stud 104b of the ratchet 104 enters into a and the link 111 and the ratchet 104 are connected.

The square hole 111a is a long hole along the moving direction of the link 111, and when the solenoid 110 is not driven and the claw portion 104c is engaged with the notch 103a, the solenoid 110 is not driven. A gap is opened in the moving direction of the link 111 by the drive of the. 111b is a hole formed in the link 111, and the stud 109b of the head support link 109 is inserted into this hole 111b.
And the head support link 109 is connected to the link 111.

As a result, when the link 111 moves in the direction of arrow a, the head support link 109 rotates about the fulcrum 109a in the direction of arrow b, the thermal head 106 moves in the direction approaching the platen 108, and the ratchet 1
04 rotates about the fulcrum 104a in the direction of arrow c and moves the claw portion 104c in a direction away from the ratchet wheel 103. When the link 111 moves in the direction of arrow d, the head support link 109 rotates about the fulcrum 109a in the direction of arrow e, and the thermal head 106 moves to the platen 1.
08, the ratchet 104 rotates about the fulcrum 104a in the direction of the arrow f, and the ratchet 104 rotates in the direction of the arrow f.
c moves toward the ratchet wheel 103.

Reference numeral 112 denotes a used thermal transfer film 101.
A take-up shaft 112 for taking up
a gear coaxially attached to a, 114 a gear 113
The meshing gear 115, the shaft of the gear 114, and the torque limiter 116 coaxially attached to the shaft 115.
117 is a gear which meshes with the torque limiter 116, and 118
Is a DC motor for driving the gear 118, and 119 is a DC motor for driving the gear 118. The driving force of the DC motor 119 is the gear 118, the gear 117, the torque limiter 116,
It is transmitted to the winding shaft 112 via a transmission path formed by the gear 114 and the gear 113.

Reference numerals 120a to 120d are guide rollers for feeding the thermal transfer film. FIG. 4 is a time chart showing a conventional operation sequence. In order to start an operation related to printing based on the position of the medium 107 sent, the medium 1
07 is provided distal print timing sensor (not shown) for detecting, for example, X ₁ mm before the printing start position of, this print timing sensor detects that has passed the tip of the medium 107, CPU (not shown) the medium 107 X ₁ mm
Printing is started after transportation.

Here, first, when the medium 107 is conveyed to the position X ₃ mm before the print start position, the conveyance is temporarily stopped, and then the solenoid 110 is operated. When the solenoid 110 is driven, the link 111 is attracted in the direction of arrow a, and when the link 111 is attracted in the direction of arrow a, the stud 9b enters the hole 111b and the link 1
Since 11 and the head support link 109 are connected, the head support link 109 rotates about the fulcrum 109a in the arrow b direction.

At this time, the ratchet 104 and the link 11
Since the stud 104b connecting 1 is inserted into the square hole 111a with a gap in the moving direction of the link 111 due to the suction of the solenoid 110, even if the link 111 moves in the direction of the arrow a, its displacement will be immediately. Ratchet 1
It is not transmitted to 04, the ratchet 104 is the link 111.
The rotation is not started at the same time as the movement of the. When the link 111 moves in the direction of the arrow a to some extent, the end of the square hole 111b hits the stud 104b, and the link 111 further moves in the direction of the arrow a, whereby the ratchet 104 rotates in the direction of the arrow c around the fulcrum 104a. ..

Thus, first, the thermal transfer film 101 is sandwiched by the thermal head 106 with the medium 107 sandwiched between the platen 1 and the thermal transfer film 101.
After being pressed to 08, the claw portion 104c of the ratchet 104 is adapted to come off the notch 103a of the ratchet wheel 103. The thermal transfer film 101 is moved to the medium 107 by the thermal head 106 by operating the solenoid 110.
After pressing the claw portion 104c of the ratchet 104 out of the notch 103a of the ratchet wheel 103,
The feeding of the medium 107 is restarted.

When the medium 107 is conveyed to the position X ₂ mm before the print start position, the DC motor 119 is driven to start winding the thermal transfer film 101. And
When the medium 107 is conveyed to the print start position, the thermal head 106 is driven to print while the printed portion of the thermal transfer film 101 is wound around the winding shaft 112.

Here, when the distance between the thermal head 106 and the guide roller 120b closest to the thermal head 106 in the feeding direction of the thermal transfer film 101 is Amm, the medium 107 is conveyed by Amm after printing is completed.
The driving of the solenoid 110 is stopped. Solenoid 110
When the driving of the ratchet is stopped, the ratchet 104 rotates in the direction of the arrow d around the fulcrum 104a until it hits the stopper 105 by a reset spring (not shown), and
4c engages with the notch 103a of the ratchet wheel 103. In addition, the head fulcrum link 111 is the fulcrum 111
The thermal head 106 rotates in the direction of arrow e around a.
The pressing of the thermal transfer film 101 due to is released.

After a lapse of a predetermined time after printing, as described above, the claw portion 104c of the ratchet 104 engages with the notch 103a of the ratchet wheel 103 to fix the rotation of the feeding shaft 102, and then the driving of the DC motor 119 is stopped. Then, the winding of the thermal transfer film 101 is stopped.

[0017]

In the thermal transfer printer, the printing time occupies about half of the processing time per medium, but in the conventional thermal transfer printer, the feeding of the medium is temporarily stopped before printing. Then, after the thermal transfer film is pressed against the stopped medium by the thermal head, the feeding of the medium is restarted, so that there is a problem that the processing time per medium becomes long.

FIG. 5 is an explanatory view showing a conventional problem. In order to increase the processing speed in the above-mentioned conventional thermal transfer printer, the thermal head presses the thermal transfer film without stopping the feeding of the medium before printing. Then, even though the medium is being sent, the thermal transfer film is stopped, so when the thermal transfer film is pressed against the medium, it is rubbed,
As shown in FIG. 5, there is a problem that dirt is attached.

As described above, the present invention solves the problem that the processing time is increased by temporarily stopping the feeding of the medium before printing, or the problem that the medium is stained by not stopping the feeding. It was done by. That is, it is an object of the present invention to provide a thermal transfer film feeding mechanism in a thermal transfer printer that does not stop the feeding of a medium before printing and is free from stains.

[0020]

In order to achieve this object, a thermal transfer film feeding mechanism in a thermal transfer printer of the present invention comprises a long belt-shaped thermal transfer film and a payout shaft around which an unused portion of the thermal transfer film is wound. A take-up shaft around which a used portion of the thermal transfer film is taken up, a drive source for driving the take-up shaft, and a thermal head for printing by pressing the thermal transfer film against a medium sent in the feeding direction of the thermal transfer film. , A platen arranged to face the thermal head, a means for moving the thermal head toward and away from the platen, and a feed rate of the thermal transfer film before the thermal head presses the thermal transfer film onto the medium. And means for traveling in synchronism with.

[0021]

According to the present invention having the above-described structure, when the medium is fed for printing, the thermal transfer film is run in synchronization with the feeding speed and the thermal head presses the thermal transfer film against the medium. Then, the thermal transfer film is printed on the thermal head while being wound on the winding shaft.

[0022]

Embodiments will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a feeding mechanism of a thermal transfer film in a thermal transfer printer according to an embodiment of the present invention. In the figure, 1 is a long belt-shaped thermal transfer film, and 2 is a feeding shaft around which an unused portion of the thermal transfer film 1 is wound. Reference numeral 3 denotes a ratchet wheel mounted coaxially with the payout shaft 2, and a gear-shaped notch 3a is provided on the outer periphery of the ratchet wheel 3.

4 is a ratchet, 4a is this ratchet 4
The fulcrum 4b that serves as the center of rotation of the stud 4b is formed at one end of the fulcrum 4a so as to project therefrom. The ratchet 4, which is a claw, rotates about a fulcrum 4a, so that the claw 4c moves toward and away from the notch 3a of the ratchet wheel 3.

Reference numeral 5 is a stopper for restricting the rotation of the ratchet 4, and when the ratchet 4 rotates to a position where it hits the stopper 5, the claw portion 4c engages with the notch 3a of the ratchet wheel 3. Reference numeral 6 denotes a thermal head that performs printing while pressing the thermal transfer film 1 against the medium 7 that is fed along the feeding direction of the thermal transfer film 1 by a mechanism (not shown), and 8 denotes a platen that is arranged to face the thermal head 6. The thermal transfer film 1 and the medium 7 are sandwiched between the platen 8 and the platen 8, and the ink of the thermal transfer film 1 is transferred to the medium 7 by the thermal head 6 to perform printing.

Reference numeral 9 denotes a head support link, and 9a denotes a fulcrum around which the head support link 9 rotates. The thermal head 6 is fixed to one end of the head support link 9 with the fulcrum 9 interposed therebetween. Head support link 9 is fulcrum 9a
By rotating about, the thermal head 6 moves in the direction of approaching and separating from the platen 8. Numeral 9b is a stud projectingly formed on the other end of the head support link 9 with the fulcrum 9a interposed therebetween.

Reference numeral 10 is a solenoid for moving the ratchet 4 and the thermal head 6, and 11 is a link attached to the movable core of the solenoid 10. Reference numeral 11a is a square hole formed in the link 11, and the stud 4b of the ratchet 4 is inserted into the square hole 11a to connect the link 11 and the ratchet 4. The square hole 11a has a long hole shape along the moving direction of the link 11, and when the solenoid 10 is not driven and the claw portion 4c is engaged with the notch 3a, it is driven by the solenoid 10. A gap is opened in the moving direction of the link 11.

Reference numeral 11b is a hole formed in the link 11, and the stud 9b of the head support link 9 is inserted into this hole 11b to connect the link 11 and the head support link 9. As a result, when the link 11 moves in the direction of the arrow f, the head support link 9 rotates in the direction of the arrow g around the fulcrum 9a to move the thermal head 6 toward the platen 8, and the ratchet 4 moves the fulcrum 4a. Arrow h in the center
The claw portion 4c moves in the direction away from the ratchet wheel 3. When the link 11 moves in the direction of arrow i, the head support link 9 rotates about the fulcrum 9a in the direction of arrow j to move the thermal head 6 in the direction away from the platen 8, and the ratchet 4 moves around the fulcrum 4a. In the direction of arrow k, the claw portion 4c moves in the direction of approaching the ratchet wheel 3.

12 is a winding shaft for winding the used thermal transfer film 1, 13 is a gear mounted coaxially with the winding shaft 12, 14 is a gear meshing with the gear 13,
Reference numeral 15 is a shaft of the gear 14, and 16 is a torque limiter coaxially attached to the shaft 15. 17 is a torque limiter 16
Gears meshing with each other, 18 gears meshing with the gear 17, 19
Is a DC motor that drives the gear 18, and the DC motor 1
The driving force of 9 is gear 18, gear 17, torque limiter 1
It is transmitted to the take-up shaft 12 via a transmission path composed of 6, a gear 14, and a gear 13.

Reference numerals 20a to 20d are guide rollers for feeding the thermal transfer film. FIG. 2 is a time chart showing the operation sequence of this embodiment. In order to start an operation relating to printing based on the position of the medium 7 sent, a print timing sensor (not shown) for detecting the leading end of the medium 7 is provided, for example, X ₁ mm before the print start position. Detects that the tip of the medium 7 has passed,
The CPU (not shown) starts printing after the medium 7 is conveyed by X ₁ mm.

First, when the medium 7 is conveyed to a position (Y ₁ + Y ₂ ) mm before the print start position, the medium 7 is conveyed.
The DC motor 19 starts to rotate while being continuously fed.
When the DC motor 19 rotates, its driving force is changed to the gear 18,
Gear 17, torque limiter 16, gears 15, 14, 13
Is transferred to the take-up shaft 12 via the heat transfer film 1
Try to wind up. At this time, since the claw portion 4c of the ratchet 4 meshes with the notch 3a of the ratchet wheel 3, the feeding shaft 2 is prevented from rotating and the wound thermal transfer film 1 cannot be fed, and therefore the winding shaft 12 Therefore, the thermal transfer film 1 cannot be wound up, but since the driving force of the DC motor 19 is transmitted to the winding shaft 12, the tension of the thermal transfer film 1 is increased.

At this time, since the torque limiter 16 is provided in the transmission path of the driving force from the DC motor 19 to the winding shaft 12, the gears cannot be rotated even though the driving force is transmitted. This prevents damage to each gear, deterioration of the DC motor 19, and cutting of the thermal transfer film 1 due to excessive tension applied to the thermal transfer film 1 due to such a load.

When the medium 7 is conveyed to Y ₂ mm before the print start position, the solenoid 10 is operated while continuously feeding the medium 7. When the solenoid 10 is driven, the link 11 is attracted in the direction of arrow f, and when the link 11 is attracted in the direction of arrow f, the stud 9 is inserted into the hole 11b.
Since b enters and the link 11 and the head support link 9 are connected, the head support link 9 rotates about the fulcrum 9a in the arrow g direction.

At this time, since the stud 4b connecting the ratchet 4 and the link 11 is inserted into the square hole 11a with a gap in the moving direction of the link 11 due to the suction of the solenoid 10, the link 11 is in the direction of arrow a. Even if the ratchet 4 moves, the displacement is not immediately transmitted to the ratchet 4, and the ratchet 4 does not start rotating at the same time when the link 11 starts moving. And to some extent link 1
When 1 moves in the direction of arrow f, the end of the square hole 11b hits the stud 4b, and further the link 11 moves in the direction of arrow f, causing the ratchet 4 to move the arrow h around the fulcrum 4a.
Rotate in the direction.

Here, after the pawl portion 4c of the ratchet 4 is disengaged from the notch 3a of the ratchet wheel 3, the pawl portion 4c or the stud 4b is provided from the fulcrum a of the ratchet 4 so that the thermal head 6 presses the thermal transfer film 1. And the length from the fulcrum 9a of the head support link 9 to the thermal head 6 or the stud 9b,
The movement amount of the head 6 due to the movement of the link 8 is smaller than the movement amount of the claw portion 4c due to the movement of the link 8.

As a result, by driving the solenoid 10, the claw portion 4c of the ratchet 4 is first disengaged from the notch 3a of the ratchet wheel 3 and the payout shaft 2 becomes rotatable. As described above, since the tension of the thermal transfer film 1 is increased, when the feeding shaft 2 becomes rotatable, the tension causes the thermal transfer film 1 to move to the medium 7.
And is wound around the winding shaft 12 at a speed substantially synchronized with the feeding speed of the.

The thermal head 6 presses the thermal transfer film 1 against the platen 8 while sandwiching the medium 7 while the thermal transfer film 1 is vigorously running in synchronization with the feeding speed of the medium 7 due to the tension. When the medium 7 is conveyed to the print start position, the thermal head 6 is driven to print while the printed portion of the thermal transfer film 1 is wound around the winding shaft 12.

Here, when the distance between the thermal head 6 and the guide roller 20b closest to the thermal head 6 in the feeding direction of the thermal transfer film 1 is set to Bmm, the medium 7 is conveyed by Bmm after the printing is completed, the solenoid 10 is moved. Stop driving. When the driving of the solenoid 10 is stopped, the link 11 is moved to the arrow i
The head support link 9 and the fulcrum 9
By rotating in the direction of arrow j around a, the pressing of the thermal transfer film 1 by the thermal head 6 is released.

When the link 11 moves in the direction of arrow i, the square hole 11a also moves in the same direction, and the ratchet 4
The arrow k around the fulcrum 4a until it hits the stopper 5.
Rotate in the direction. When the ratchet 4 rotates to a position where it abuts the stopper 5, the claw portion 4c engages with the notch 3a of the ratchet wheel 3 and fixes the rotation of the payout shaft 2 positioned coaxially.

In order to wind the heat transfer film 1 evenly, after the completion of printing, a predetermined time elapses and the claw portion 4c of the ratchet 4 engages with the notch 3a of the ratchet wheel 3 to rotate the feeding shaft 2 as described above. After fixing, D
The driving of the C motor 19 is stopped to stop the winding of the thermal transfer film 1. In this embodiment, the DC motor 19 is driven with the feeding shaft 2 fixed, and the take-up shaft 12
By winding the thermal transfer film 1 with, the tension applied to the thermal transfer film 1 is increased, and the fixing of the payout shaft 2 is instantaneously released, so that the feeding speed of the thermal transfer film 1 is not directly controlled, Although the thermal transfer film 1 was advanced by this tension, the winding shaft 12
Between the thermal head 6 and the thermal head 6, means for applying a feeding force to the thermal transfer film 1 such as a capstan and a pinch roller are separately provided, and when the thermal head 6 presses the thermal transfer film 1 against the platen, the thermal transfer film 1 is moved by the feeding means. The feeding speed may be increased so that the feeding is performed in synchronization with the feeding speed of the medium 7.

[0040]

As described above, according to the present invention, when the thermal transfer film is pressed against the medium, the thermal head presses the thermal transfer film onto the medium while the thermal transfer film is running in synchronization with the feeding speed of the medium. Therefore, it is not necessary to temporarily stop the feeding of the medium when pressing the thermal transfer film against the medium because the medium becomes dirty when the feeding speed of the medium and the thermal transfer film is different,
This has an effect that the time required for printing the medium per sheet can be shortened and the processing speed can be increased.

Further, since it can be carried out without largely changing the conventional mechanism, there is an effect that an increase in cost can be suppressed.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a heat transfer film feeding mechanism in an embodiment of the present invention.

FIG. 2 is a time chart showing the operation sequence of the present embodiment.

FIG. 3 is a configuration diagram showing a conventional thermal transfer film feeding mechanism.

FIG. 4 is a time chart showing a conventional operation sequence.

FIG. 5 is an explanatory diagram showing a conventional problem.

[Explanation of symbols]

 1 Thermal Transfer Film 2 Feeding Axis 6 Thermal Head 7 Medium 8 Platen 10 Solenoid 12 Winding Axis 19 DC Motor

Claims (1)

[Claims] 1. A long-strip thermal transfer film, a payout shaft around which an unused portion of the thermal transfer film is wound, a winding shaft around which a used portion of the thermal transfer film is wound up, and a drive for driving the winding shaft. Source, a thermal head that prints by pressing the thermal transfer film against a medium that is fed along the direction of the thermal transfer film, a platen that faces the thermal head, and a thermal head that moves close to and away from the platen. And a means for moving the thermal transfer film in synchronization with the feeding speed of the medium before the thermal head presses the thermal transfer film against the medium. ..