JPH1199732A - Thermal recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of wrinkles in an ink ribbon due to a high temperature produced by a thermal head, thereby making it possible to form a high-definition image without any image defect. SOLUTION: An electromagnetic clutch is provided on an unwinding shaft 39 for an ink ribbon (r) for controlling the start and stop of rotation of the unwinding shaft 39 by, for instance, suitably switching it on and off via a CPU. When a cart (recording medium) C is transferred to between a platen roller 30 and a thermal head 25, the electromagnetic clutch 50 is switched on 0.5 to 3 seconds before a leading end of the card C enters between the roller and the head so as to transmit the driving of a ribbon driving motor 35 to the unwinding shaft 39 to thereby start the unwinding of a ribbon, thereby putting the ink ribbon (r) in a transfer state before a recording is started on the card C with the thermal head 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal recording apparatus such as a thermal printer for recording on a recording medium such as paper or a card using an ink ribbon for thermal transfer.
In particular, while transporting the recording medium between the platen and the thermal head, while feeding the ink ribbon, the platen is pressed against the thermal head with the ink ribbon and the recording medium interposed, and the ink on the ink ribbon is ejected by the thermal head. The present invention relates to a thermal recording apparatus that records an image by thermally transferring it to a recording medium.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 5, for example, as shown in FIG. 5, an ink ribbon denoted by reference numeral 1 is wound between a feeding core 2 and a winding core 3 in this type of thermal recording apparatus. There is a configuration in which a tip 4a of a thermal head 4 fixed to a head holder (not shown) is applied, and a platen 5 is provided so as to be able to freely contact and separate from the thermal head 4.

At the time of recording, the recording medium P is transported between the platen 5 and the thermal head 4, while the electromagnetic clutch is turned on at the timing when the leading end of the recording medium P enters during this time (not shown) to drive the ribbon. The drive of the motor is transmitted to the cores 2 and 3 via the drive transmission mechanism so that the ink ribbon 1 is sent when the leading end of the recording medium P enters between the platen 5 and the thermal head 4.

[0004]

However, in such a conventional thermal type recording apparatus, even if the electromagnetic clutch is turned on in synchronization with the timing at which the leading end of the recording medium P enters between the platen 5 and the thermal head 4, it is normal. Actually, the start timing of the ribbon feeding is delayed due to the stacking of the play in the drive transmission mechanism described above, so that the recording by the thermal head 4 is started before the ink ribbon 1 is fed. Then, until ribbon feeding starts,
The thermal energy of the thermal head 4 is applied to the same portion of the ink ribbon 1 in the stopped state, and the high heat causes the ink ribbon 1 to soften and generate a long ribbon wrinkle in the traveling direction. There is a problem that image quality is deteriorated.

[0005]

Therefore, according to the first aspect of the present invention, a recording medium such as a card C is transferred to a platen such as a platen roller 30 and a thermal head 25 as described in the following embodiments. And the platen is transferred to the thermal head 25 with the ink ribbon r and the recording medium interposed therebetween while transmitting the ink ribbon r by transmitting the drive of the ribbon drive motor 35 via a clutch such as the electromagnetic clutch 50. In a thermal recording apparatus in which the thermal head 25 presses and thermally transfers the ink of the ink ribbon r to the recording medium to record an image, before the leading end of the recording medium enters between the platen and the thermal head 25, Drive control means for turning on the clutch in accordance with the timing of starting ribbon feeding, And butterflies.

According to a second aspect of the present invention, in the thermal recording apparatus according to the first aspect, for example, as described in the following embodiment shown in the drawings, the recording medium passing between the thermal head 25 and the platen. After the end of the recording, the drive control means continuously turns on the clutch for a predetermined time to continue the ribbon feeding.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows a thermal color printer according to the present invention, and shows an overall schematic configuration of an internal mechanism thereof.

This thermal color printer is a thermal recording apparatus that uses a card as a recording medium and records a color image on the card to create a telephone card, a cash card, or the like.

Reference numeral 10 in the drawing indicates an outer case in the form of a horizontally long box of the illustrated printer. A card supply unit 12 is provided in the outer case 10 on the right end side in the figure. Card supply unit 12
Is provided with a supply roller 13 for stacking a large number of recording medium cards C and feeding the cards C below. A regulating plate 14 is provided on the left side of the supply roller 13 in the drawing, and a gap d through which one card passes is formed below the leading end of the regulating plate 14.

Reference numeral 15 in FIG.
Is a card transport path for transporting from right to left in the figure. The card transport path 15 is provided with a pair of registration rollers 17 at the start end side in the card transport direction, and the pair of discharge rollers 18 at the opposite end side.
Are provided, and a plurality of pairs of transport rollers 19 are arranged therebetween.

On the upper side of the card transport path 15, there are provided yellow, magenta, cyan and black color recording sections 20 to 23 in order from the start end to the end. The recording units 20 to 23 have substantially the same configuration, and are supported between side plates (not shown) provided in the front-rear direction in FIG. FIG.
The yellow recording section 20 is shown in FIG.

The recording section 20 has an opening / closing cover 2 on its upper side.
4, and the opening / closing cover 24 is supported by a support shaft 26 so as to be rotatable around the support shaft 26. The holder 27 of the thermal head 25 is attached to the opening / closing cover 24. The thermal head 25 has an elongated plate shape in the depth direction in the figure, and holds both ends in the length direction between hanging portions 27 a provided on both sides in the depth direction of the holder 27. Then, the leading end 25a is brought into contact with the ink ribbon r for thermal transfer.

The ink ribbon r is wound around the right and left delivery cores 31 and the take-up cores 32 in the ribbon cassette 11 having an outer shape of binoculars, and is wound between the cores 31 and 32. The ribbon cassette 11 has cutout windows 11a and 11b between the cores 31 and 32 on the upper and lower surfaces. Then, the hanging portion 27a of the holder 27 is
a, the leading end 25a of the thermal head 25 is applied to the ink ribbon r so as to be exposed to the lower outside through the cutout window 11b.

Further, the recording unit 20 includes the thermal head 2
5, a platen roller 30 is attached to the thermal head 25.
Are provided so as to be movable by a contact / separation mechanism A between a pressing position and a retracted position indicated by a chain line.

In the contact / separation mechanism A, an arm 28 having a U-shape is provided rotatably at both ends of a pair of transport rollers 19, and both ends of a platen roller 30 are rotatably attached to one end of the arm 28. Further, the arm 28 has a pin m
n, one end of a tension spring 29 is hung on one pin m,
The other end is hung on a fixed shaft 33 attached to the side plate to urge the arm 28 to rotate counterclockwise in FIG. On the other hand, the other pin n is connected to the support shaft 34a by a step motor (not shown).
Abut on an elliptical cam 34 that rotates about the center.

When recording is not performed, the elliptical cam 34 is rotated to the dashed line position against the tension spring 29, and the arm 28 is rotated clockwise in FIG. 4 to hold the platen roller 30 at the retracted position. To the standby state.

In FIG. 4, reference numeral 35 denotes a ribbon drive motor 35, and reference numeral 36 denotes a fan for cooling the thermal head.

When recording a color image on the card C using the illustrated thermal color printer, a start switch (not shown) is pressed, the supply roller 13 is rotated, and one card C is sequentially inserted from the bottom through the gap d. And then guided to the card transport path 15.

Then, after the first card C is abutted against the registration roller pair 17 and stopped, the card C is conveyed between the thermal head 25 of the yellow recording section 20 and the platen roller 30 at a certain timing.

When the leading end of the card C enters between the thermal head 25 and the platen roller 30, the elliptical cam 34
Is rotated 180 degrees to the solid line position, and the arm 28 is rotated counterclockwise in FIG.
Is pressed against the thermal head 25 via the card C and the yellow ribbon r, and the ink of the ribbon is thermally transferred to the card C to record an image of the first color.

Thereafter, just before the rear end of the card C passes between the thermal head 25 and the platen roller 30, the platen roller 30 is separated from the thermal head 25 by the contact / separation mechanism A and returned to the retracted position as described above. . Then, the card C is conveyed to the magenta recording unit 21, and the platen roller 30 is pressed against the thermal head 25 via the card C and the magenta ribbon r in the same manner, and a second color image is recorded on the card C.

Thereafter, the card C is successively conveyed to the next cyan recording section 22 and black recording section 23 through the card conveying path 15, and if necessary, the recording sections 22 and 23 are conveyed.
Similarly, the ink of the ink ribbon r is thermally transferred onto the card C to record a composite color image. And after recording,
The card C is discharged to a discharge unit (not shown) by the discharge roller pair 18.

Further, the following cards C are sequentially conveyed through the card conveying path 15 at a time with respect to each other.
Similarly, the respective color inks are thermally transferred in the respective recording units 20 to 23, a composite color image is recorded on each of them, and is discharged to the discharge unit.

FIG. 1 shows each of the above-described color recording units 20 to 20.
23 shows a ribbon drive mechanism for feeding an ink ribbon r provided in the printer.

This ribbon drive mechanism is provided with a gear train G for transmitting the drive of the ribbon drive motor 35 to the feeding shaft 39 of the ink ribbon r provided in the yellow recording section 20. Further, a pulley 38 provided on the feeding shaft 39, between pulleys 40 on the feed shaft 39 of magenta recording unit 21, and passes over the timing belt b _1. Similarly, the pulley 40
And between the pulleys 41 on the feeding shaft 39 of the cyan recording unit 22,
And a timing belt b between the pulley 41 and the pulley 42 on the feeding shaft 39 of the black recording unit 23.
_{1 so} that the drive of the ribbon drive motor 35 can be transmitted to each payout shaft 39.

Further, in the recording units 20 to 23, another pulley 43 is provided on each feeding shaft 39, and a small speed-up pulley 45 is provided on each winding shaft 44. looped timing belt b ₂ between, to allow transmission respectively by accelerating the rotation of the feeding shaft 39 to the take-up shaft 44.

By the way, in the ribbon driving mechanism described above,
Payout shaft 39 and take-up shaft 44 for each color ink ribbon r
Is rotatably supported by the above-described rear side plate 47 and a support plate 48 provided on the back side thereof, similarly to the ribbon drive transmission section of the yellow recording section 20 shown in FIG.

The feeding shaft 39 and the winding shaft 4
In 4 of the base end side, passing over the timing belt b ₂ between the pulleys 43, 45 as described above, comprising over one side of the timing belt b ₁ to the pulley 38.

On the other hand, hubs 49 are attached to the leading ends of the feeding shaft 39 and the winding shaft 44, respectively.
, A cylindrical feeding core 31 and a winding core 32 are detachably fitted. Reference numeral 51 in the figure denotes a buffer spring when the cores 31 and 32 are fitted to the hub 49.

An electromagnetic clutch ("clutch" according to the present invention) 50 is mounted on the feed shaft 39 between the feed shaft and the transmission gear g of the gear train G described above. Although not shown, the electromagnetic clutch 50 is, for example, a CP.
U ("drive control means" in the present invention), and the CPU controls the rotation / stop of the feed shaft 39 by appropriately turning on / off the CPU.

In the thermal color printer described above, at the time of recording, when the card C is conveyed between the platen roller 30 and the thermal head 25 at the timing by the registration roller pair 17, the leading end of the card C enters between them. For example, 0.5 to 3 seconds before, the electromagnetic clutch 50 is turned on and the drive of the ribbon drive motor 35 is transmitted to the feeding shaft 39 to start ribbon feeding.

[0032] Then, while rotating the feeding core 31 with feed shaft 39, the rotation of the feeding shaft 39, conveyed to accelerated the winding shaft 44 via the timing belt b _2, unwinding core winding core 32 31 Spin faster. Then, the ink ribbon r is drawn out from the payout core 31 while being stretched between the cores 31 and 32, and is taken up by the take-up core 32.

Then, the card C enters between the platen roller 30 and the thermal head 25, and when the platen roller 30 is pressed against the card C to start recording of the first color, the ink ribbon r is already in the transport state. .

After that, even after the recording of the first color on the card C is completed, the electromagnetic clutch 50 is kept on for 0.5 to 3 seconds, for example, and the ribbon feeding is continued. Then, just before the rear end of the card C passes between the thermal head 25 and the platen roller 30, the platen roller 30 is released. Then, after a lapse of 0.5 to 3 seconds, the electromagnetic clutch 50 is turned off for the first time to temporarily stop the ribbon feeding. Note that, as described above, the time for which the conveyance of the ink ribbon r is advanced or the conveyance of the ink ribbon r is continued after the recording is performed for about 0.5 to 3 seconds.
Is within an allowable range not to wastefully consume.

Also in the magenta / cyan / black recording units 21 to 23, similarly, 0.5 to 3 seconds before the card C enters between the platen roller 30 and the thermal head 25,
Each electromagnetic clutch 50 is turned on to start feeding the ribbon, and at the start of recording, the ink ribbon r is already in the transport state. After completion of the recording, the electromagnetic clutch 50 is turned on for 0.5 to 3 seconds to continue the ribbon feeding.

Reference numeral 55 in FIG. 2 denotes a torque limiter that keeps the tension applied to the ink ribbon r constant by slipping when the rotation of the winding shaft 44 exceeds a certain torque. Reference numeral 56 denotes a ribbon control pulse generator that detects when the ink ribbon r has jammed and the winding shaft 44 has stopped.

[0037]

Therefore, according to the present invention, the clutch is turned on at the time of starting the ribbon feeding before the leading end of the recording medium enters between the platen and the thermal head during recording. Since the ink ribbon is already in the transport state, recording does not start with the ink ribbon stopped as in the related art, thereby preventing wrinkles from occurring in the ink ribbon due to the high heat of the thermal head. As a result, a high-quality image without image omission can be formed.

According to the second aspect of the present invention,
Since the ribbon feed is not stopped after recording on the recording medium, but the clutch is turned on for a certain period of time and the ribbon feed is continued, it is possible to prevent the ink ribbon from wrinkling due to the high residual heat of the thermal head after printing is completed. It can also be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a ribbon drive mechanism provided in a thermal color printer according to the present invention.

FIG. 2 is a configuration diagram showing a ribbon drive transmission unit of a yellow recording unit of the thermal color printer viewed from above without a ribbon cassette;

FIG. 3 is an overall schematic configuration diagram of an internal mechanism of the thermal color printer.

FIG. 4 is a configuration diagram of a yellow recording section of the thermal color printer.

FIG. 5 is a schematic configuration diagram of a recording unit of a conventional thermal recording apparatus.

[Explanation of symbols]

 25 thermal head 30 platen roller (platen) 35 ribbon drive motor 50 electromagnetic clutch (clutch) C card (recording medium) r ink ribbon

Claims (2)

[Claims] 1. A recording medium is conveyed between a platen and a thermal head, and the driving of a ribbon drive motor is transmitted via a clutch to feed an ink ribbon. A thermal recording apparatus for recording an image by pressing an ink on the ink ribbon onto the recording medium with the thermal head by pressing against the head, wherein the ribbon before the leading end of the recording medium enters between the platen and the thermal head. A thermal recording apparatus, comprising: drive control means for turning on the clutch in accordance with the timing of starting feeding. 2. The thermal printer according to claim 1, wherein after the recording of the recording medium passing between the thermal head and the platen is completed, the drive control means continuously turns on the clutch for a predetermined time to continue ribbon feeding. Expression recording device.