JP2902518B2 - Thermal transfer printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer,
In particular, the present invention relates to a thermal transfer printer that can reduce the amount of ink ribbon winding and reduce the amount of ink ribbon consumed.

[0002]

2. Description of the Related Art FIG. 7 shows a conventional general thermal transfer printer, in which a platen 2 in the form of a flat plate is disposed substantially at the center of a frame 1 of the printer so that its printing surface is substantially vertical. A carriage shaft 3 is arranged below the front side of the platen 2 of the frame 1 in parallel with the platen 2. A flange-shaped guide portion 4 is formed at the front edge of the frame 1. A carriage 5 reciprocates along the carriage shaft 3 and the guide portion 4 on the carriage shaft 3 and the guide portion 4. It is movably mounted. A thermal head 6 is attached to the leading end of the carriage 5 so as to face the platen 2. An ink ribbon is stored on the upper surface of the carriage 5, and the ink ribbon is attached to the thermal head 6 and the platen 2. 2 and a ribbon cassette (not shown) for guiding between them. Further, on the upper surface of the carriage 5, a take-up bobbin 7 for winding the ink ribbon of the ribbon cassette and a delivery bobbin 8 for sending out the ink ribbon are provided.

[0003] A paper insertion port 9 for feeding paper (not shown) forward of the platen 2 is formed behind the platen 2, and the paper insertion port 9 is formed at a predetermined speed in the paper insertion port 9. A paper feed roller 10 for transporting the paper is provided. Below the paper feed roller 10, a pressure roller 11 that is pressed against the paper feed roller 10 is rotatably disposed, and on one side of the frame, a transmission gear group 12 is provided with the paper feed roller. A paper feed motor 13 that is driven to rotate via a motor is provided. By driving the paper feed motor 13 to rotate the paper feed roller 10, the paper inserted from the paper insertion opening 9 between the paper feed roller 10 and the pressure roller 11 is nipped and conveyed. It has been made to be.

In the conventional printer, paper is inserted from the paper insertion port 9, the paper is sandwiched between the paper feed roller 10 and the pressure roller 11, and the paper feed roller 10 is driven by a paper feed motor 13. By rotating the sheet, the sheet is transported at a predetermined speed in a direction orthogonal to the moving direction of the carriage 5. On the other hand, the thermal head 6 is pressed against the paper with a predetermined pressing force. In this state, the carriage 5 is moved, and the winding bobbin 7 is rotated to wind the ink ribbon of the ribbon cassette. By driving the thermal head 6 based on a desired printing signal, desired printing is performed on the paper.

[0005]

However, in such a conventional thermal transfer printer, printing is performed while moving the carriage 5 while the thermal head 6 is pressed against the paper. The ink ribbon is sent out from the bobbin 8 along with the movement, and the printed ink ribbon is wound up by the winding bobbin 7, so that the winding amount of the ink ribbon by the winding bobbin 7 And the ink ribbon is consumed in a very short time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide a thermal transfer printer capable of reducing the amount of ink ribbon taken up and the amount of ink ribbon consumed. is there.

[0007]

In order to achieve the above object, a thermal transfer printer according to the present invention has a thermal head disposed on a carriage reciprocally movable along a platen, and is wound on an upper surface of the carriage. A bobbin and a delivery bobbin are rotatably disposed, and a ribbon cassette containing an ink ribbon wound around a pair of reels inside an upper surface of the carriage is provided on each of the reels with the take-up bobbin and the delivery bobbin. In a thermal transfer printer which is detachably mounted so as to be engaged with the ribbon cassette, the one formed on the ribbon cassette on the upper surface of the carriage.
The second take-up bobbin and the second delivery bobbin, which are engaged with the pair of guide rollers, are respectively moved by the moving force of the carriage.
The thermal head and the paper are arranged on the second delivery bobbin in accordance with the movement of the carriage.
And applying a load greater than the pull-out force of the ink ribbon that is nipped and pulled out, so that the amount of rotation of the second take-up bobbin and the second delivery bobbin is equal to or less than the amount of movement of the thermal head. The feature is that it is set.

[0008]

According to the present invention, a key is provided on the second delivery bobbin.
Between the thermal head and paper as the cartridge moves.
It is in addition to imparting greater load than the pull-out force of the ink ribbon to be drawn, the second take-up bobbin and
Since the rotation amount of the second sending-out bobbin is set to be equal to or less than the moving amount of the thermal head, the ink ribbon is not pulled out by being pinched between the thermal head and the paper, and the thermal head is moved by the second winding bobbin. The winding amount is smaller than the moving amount of the ink ribbon. As a result, the winding amount of the ink ribbon can be reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIGS. 1 to 5 show an embodiment of a thermal transfer printer in which a ribbon cassette according to the present invention is mounted. A carriage 5 reciprocally movable along a platen 2 has a thermal head 6 attached thereto. A motor 14 for controlling the operation of contacting and separating from the platen 2 and the winding of the ink ribbon is provided, and a transmission gear 16 is meshed with an output pinion gear 15 of the motor 14. This transmission gear 16
A gear portion 18 formed on an outer peripheral surface of a cam 17 is meshed with the cam 17. On the upper surface of the cam 17, a head contact / separation cam groove 19 and a width wider than the head contact / separation cam groove 19, and , A shallowly formed ribbon winding cam groove 20 is formed.

A support shaft 21 is provided near the platen 2 of the carriage 5. In the present embodiment, the support shaft 21 is, as shown in FIG. It is formed so as to protrude. A substantially T-shaped head lever 22 constituting a head contact / separation mechanism is mounted on the support shaft 21 so as to be swingable about the support shaft 21. A head mount 23 facing the platen 2 is fixed by screwing. The thermal head 6 is mounted on the surface of the head mount 23 facing the platen 2, and a stopper 24 is provided on the head mount 23 so as to have a predetermined distance from the back surface of the head mount 23. It is protruding.

A substantially L-shaped head pressure contact lever 25 is attached to the support shaft 21 so as to be swingable about the support shaft 21.
One end of the cam 17 has a cam groove 19 for head contact and separation of the cam 17.
Is formed. The other end of the head pressure lever 25 is disposed between the back surface of the head mount 23 of the head lever 22 and the stopper 24. The other end of the head pressure lever 25 has a spring holding portion 27. Is erected. Further, the spring holding part 2
A strong pressure contact spring 28 is interposed between the head 7 and the head mount 23, and the head pressure contact lever 25 is brought into contact with the stopper 24 of the head lever 22 by the urging force of the strong pressure contact spring 28. In this state, the head pressure lever 25 and the head lever 22 are integrally rotated by the rotation of the cam 17 when the head is moved up and down.

A drive gear 30 meshed with a rack 29 formed in the printer is rotatably provided on the carriage 5 around a support shaft 31. The support shaft 31 and the head lever 22 And a weak pressure contact spring 32 having a spring pressure weaker than that of the strong pressure contact spring 28 so that the head lever 22 always applies a biasing force in a direction of pressing the thermal head 6 to the platen 2. I have.

A swing plate 33 is attached to the support shaft 31 so as to be swingable about the support shaft 31.
A pin 34 is formed at one end of the rocking plate 33 to be engaged with the ribbon winding cam groove 20 of the cam 17. Here, the pin 34 of the swing plate 33 is formed to be thicker than the width of the head contact / separation cam groove 19.
Does not fall into the cam groove 19 for head contact / separation. Support shafts 35 and 36 are provided on both sides of the support shaft 31 of the rocking plate 33, respectively.
The take-up transmission gear 37 and the delivery transmission gear 38 meshed with the drive gear 30 are rotatably attached to the gears 5 and 36, respectively.

As shown in FIG. 1, the carriage 5 is provided with a take-up bobbin 7 for winding an ink ribbon and a delivery bobbin 8, respectively. As shown in FIG.
Below the winding bobbin 7, the winding transmission gear 3
A take-up gear 39 meshed with 7 is coaxially mounted via a friction mechanism (not shown).

Further, in the present embodiment, the carriage 5 is provided with a second winding bobbin 40 and a second delivery bobbin 41, and below the second winding bobbin 40, A second winding gear 43 meshed with a winding gear 39 of the winding bobbin 7 via a transmission gear 42 is coaxially mounted. Below the second delivery bobbin 41, a second delivery gear 45 meshed with the delivery transmission gear 38 via a plurality of transmission gears 44 is coaxially mounted via a friction mechanism (not shown). I have.
By the swing of the swing plate 33, the take-up transmission gear 37 and the delivery transmission gear 38 are meshed with the take-up gear 39 and the transmission gear 44, respectively, whereby the take-up bobbin 7, the second take-up bobbin 40 and the second delivery bobbin 41 are rotationally driven.

In this case, in the present embodiment, the second delivery bobbin 41 is provided with an ink ribbon which is pulled out by being sandwiched between the thermal head 6 and a sheet by the friction mechanism by the friction mechanism. A load greater than the pull-out force is applied, and the second winding bobbin 4
0 is set so that the winding amount is equal to or less than the moving amount of the thermal head 6 by setting the gear ratio of the winding gear 39, the transmission gear 42, and the second winding gear 43. Further, the winding bobbin is, for example, 105 to 12 with respect to the winding amount of the second winding bobbin.
The winding amount is set to be about 0%.

Further, on the upper surface of the carriage 5, a photo sensor 4 for detecting the end of the ink ribbon to be used and for detecting the color marker of the color ink ribbon.
6 are provided.

Also, on the upper surface of the carriage 5, FIG.
As shown in FIG. 7, a ribbon cassette 48 containing an ink ribbon 47 is detachably mounted. The ribbon cassette 48 is engaged with the winding bobbin 7 and the delivery bobbin 8 and A pair of reels (not shown) around which the reel 47 is wound is provided. The ribbon cassette 48 includes the second winding bobbin 40.
A pair of guide rollers (not shown) that are engaged with the second delivery bobbin 41 and guide the ink ribbon 47 are provided, and the thermal head 6 is inserted into the center of the ribbon cassette 48 on the platen 2 side. Recess 49 is formed. Further, the support shafts 21 are respectively provided at symmetrical positions on both sides of the concave portion 49 of the ribbon cassette 48.
A notch 50 into which is inserted is formed.

Since FIG. 1 shows a so-called multi-time ink ribbon cassette which can be used inverted, two notches 50 are formed at symmetrical positions of the concave portion 49 into which the thermal head 6 is inserted. However, in the case of a so-called one-time ribbon, the notch 50 is
It is only necessary to form them at only one place.

Next, the operation of this embodiment will be described.

First, as shown in FIG. 2, when the cam 17 is rotated to the leftmost position in the figure, the pin 26 of the head pressure lever 25 is located at the outermost periphery of the cam groove 19 for head contact / separation. 2, the head pressure lever 25 is pivoted to the left most in FIG. 2, and the head pressure lever 25 is brought into contact with the stopper 24 of the head lever 22 by the urging force of the high pressure spring 28, and the head mounting base 23 is moved. Since the thermal head 6 is operated together with the head pressing lever 25, the thermal head 6 is held in a head-up state separated from the platen 2 by the swing of the head pressing lever 25.

On the other hand, the ribbon winding cam groove 20
The swinging plate 33 is swung to the left, and the take-up transmission gear 37 and the sending-out transmission gear 38 supported by the swinging plate 33 are meshed with the take-up gear 39 and the transmission gear 44, respectively. When the drive gear 30 meshed with the rack 29 is rotationally driven by the movement of the gear 5 along the platen 2, the take-up gear 39, the second take-up gear 43, and the second take-up gear 43 are transmitted via the transmission gears 42 and 44. The delivery gear 45 is driven to rotate, and the winding bobbin 7 and the second winding bobbin 40 are rotated.
The rotation of the second delivery bobbin 41 causes the ink ribbon 47 to be wound and delivered.

At the position of the cam 17, no printing is performed, and color sensing by the photo sensor when the color ink ribbon 47 is used or the ink ribbon 4 is used.
The slack removing operation when the slack 7 is performed is performed.

Next, as shown in FIG. 3, when the cam 17 is rotated rightward by driving the motor 14 from the state shown in FIG. 2, the head pressure lever 25 is not swung, and the thermal head 6 is moved to the platen. The swinging plate 33 is swung rightward by the ribbon winding cam groove 20 while being held in the head-up state separated from the winding gear 2, and the transmission gears 42 and 44 of the swinging plate 33 are separated from the winding gear 39. You. In this state, even when the carriage 5 moves, the rotation of the driving gear 30 is not transmitted to the winding bobbin 7 and the second winding bobbin 40, and the winding operation of the ink ribbon 47 is not performed. Used for return operation or ribbon save operation.

When performing normal printing on plain paper or the like, as shown in FIG. 4, the motor 14 is further driven from the state shown in FIG. Since the pin 26 of the head pressure lever 25 is located at the position closest to the center of rotation of the head contact / separation cam groove 19, the head pressure lever 25 is
It is swung to the right most around 1. This allows
The head press lever 25 is separated from the stopper 24 of the head mount 23, and the spring holder 27 of the head press lever 25 uses a high pressure spring 28 to press the head mount 23.
Is pressed, and in this state, the head lever 22
Since the urging force of the low pressure contact spring 32 is applied, the head mount 23 is applied with a pressing force that is the sum of the urging force of the high pressure contact spring 28 and the urging force of the low pressure contact spring 32, The thermal head 6 is pressed against the platen 2 with a strong pressing force.

On the other hand, the rocking plate 33 is rotated leftward from the state shown in FIG. 3, and the winding transmission gear 37 of the rocking plate 33 is meshed with the winding gear 39 again and sent out. The transmission gear 38 is engaged with the transmission gear 44, and the operation of the carriage 5 causes the ink ribbon 47 to be wound and sent out.

In this state, by moving the carriage 5, the drive gear 30 is rotationally driven via the rack 29, and the take-up gear 39, via the transmission gears 42 and 44.
By rotating the second take-up gear 43 and the second delivery gear 45, the take-up bobbin 7, the second take-up bobbin 40, and the second delivery bobbin 41 are driven to rotate. Then, each guide roller is rotated, and the ink ribbon 47 of the ribbon cassette 48 is rotated.
While printing, the thermal head 6 is driven based on a desired print signal to print on a predetermined sheet.

At this time, in the present embodiment, the second
Since a load greater than the pulling force of the ink ribbon 47 is applied to the sending-out bobbin 41 and the winding amount of the second winding bobbin 40 is set to be equal to or less than the moving amount of the thermal head 6, The ink ribbon 47 is not pulled out by being pinched between the thermal head 6 and the paper, but is wound by the second winding bobbin 40 with a winding amount equal to or less than the moving amount of the thermal head 6. Can be reduced.

Unlike ordinary printing, when printing is performed on paper for an overhead projector (OHP) or the like, as shown in FIG.
To rotate the cam 17 further leftward, the pin 26 of the head pressure lever 25 is located at the innermost portion of the head contact / separation cam groove 19, and the head contact / separation cam groove 19 at this position Is formed large, a gap is formed between the pin 26 of the head pressure lever 25 and the cam groove 19 for head contact / separation. As a result, the head pressure contact lever 25 is rotated so as to abut against the stopper 24 by the urging force of the strong pressure contact spring 28, so that the thermal head 6 is pressed against the platen 2 by the urging force of only the weak pressure contact spring 32. , And printing can be performed with a weak pressing force as compared with normal printing. Also,
Even when the cam 17 is rotated, the take-up transmission gear 37 and the sending-out transmission gear 38 of the rocking plate 33 are held in a state of being meshed with the take-up gear 39 and the transmission gear 44, so that normal printing is performed. As in the case of (1), the operation of winding and sending out the ink ribbon 47 can be performed by the movement of the carriage 5. Also in this case, similarly to the case of printing on the plain paper, the large load on the second delivery bobbin 41 and the second take-up bobbin 40
And the winding amount less than the moving amount of the thermal head 6
The amount of winding of the ink ribbon 47 can be reduced.

As described above, by selecting the position of the cam 17 according to a necessary situation, it becomes possible to perform various operations required as a thermal transfer printer.

Therefore, in the present embodiment, a load larger than the pulling force of the ink ribbon 47 is applied to the second delivery bobbin 41 and the winding amount of the second winding bobbin 40 is controlled by the thermal head 6. Is set to be equal to or less than the moving amount of the thermal ribbon 6, and the ink ribbon 47 is wound by the second winding bobbin 40 with the winding amount equal to or less than the moving amount of the thermal head 6. As a result, the consumption of the ink ribbon 47 can be significantly reduced.

The present invention is not limited to the above-described embodiment, but can be variously modified as needed.

[0034]

As described above, in the thermal transfer printer according to the present invention, the thermal head and the paper are provided on the second delivery bobbin.
A load larger than the pulling force of the ink ribbon that is nipped and pulled out is applied to the second winding bobbin and the like .
Since the amount of rotation of the second delivery bobbin is set to be equal to or less than the amount of movement of the thermal head, the amount of winding of the ink ribbon can be reduced, and as a result, the consumption of the ink ribbon can be significantly reduced. And the like.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing one embodiment of a thermal transfer printer to which a thermal transfer printer according to the present invention is mounted.

FIG. 2 is a configuration diagram showing an ink ribbon sensing operation state of the thermal transfer printer of FIG. 1;

FIG. 3 is a configuration diagram showing a carriage return operation state by the thermal transfer printer of FIG. 1;

FIG. 4 is a configuration diagram showing a printing state on plain paper by the thermal transfer printer of FIG. 1;

FIG. 5 is a configuration diagram showing a printing state on OHP paper by the thermal transfer printer of FIG. 1;

FIG. 6 is a perspective view showing a conventional general thermal transfer printer.

[Explanation of symbols]

 2 Platen 5 Carriage 6 Thermal head 7 Take-up bobbin 8 Send-out bobbin 17 Cam 21 Support shaft 22 Head lever 25 Head press-contact lever 33 Rocking plate 37 Take-up transmission gear 38 Send-out transmission gear 39 Take-up gear 40 Second take-up Bobbin 41 Second delivery bobbin 43 Second take-up gear 45 Second delivery gear 47 Ink ribbon 48 Ribbon cassette

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 33/54 B41J 33/14

Claims (1)

(57) [Claims] 1. A thermal head is provided on a carriage reciprocally movable along a platen, and a winding bobbin and a delivery bobbin are provided on an upper surface of the carriage so as to be rotatably driven. In a thermal transfer printer, a ribbon cassette containing an ink ribbon wound on a pair of reels is detachably mounted so that each reel engages with the winding bobbin and the delivery bobbin, respectively. A second take-up bobbin and a second delivery bobbin, which are engaged with a pair of guide rollers formed on the ribbon cassette on the upper surface of the carriage, are respectively driven to rotate by the moving force of the carriage.
And the carriage is mounted on the second delivery bobbin.
The paper is pinched between the thermal head and paper
While applying a load larger than the pulling force of the ink ribbon to be ejected , the second winding bobbin and the second
(2) A thermal transfer printer , wherein the rotation amount of the delivery bobbin is set to be equal to or less than the movement amount of the thermal head.