JPS6151998B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a thermal printer.

In a conventional thermal printer, a thermal head 1 as shown in FIG. 1 is brought into contact with a heat-sensitive recording paper as shown in FIG. 2, and a heating element selectively generates heat to obtain a record on the recording paper. However, this method has many drawbacks as shown below.

1. Recording paper that changes color due to heat is used, so sufficient care must be taken when storing the recording paper.

2 When heat is applied to printed recording paper, the color changes and the record becomes illegible.

3. Because special recording paper is used, it cannot be printed on plain paper.

4 Heat-sensitive materials may melt and adhere to the thermal head and accumulate, impairing the clarity of printing.

5 It is difficult to correct what has been printed once.

6 Multi-color printing is difficult.

A thermal printer was devised as an improvement on the above-mentioned thermal printer, in which ink applied to a printing tape is melted by a thermal head and transferred to recording paper.

FIG. 3 shows a printing tape 2 for use in the above-mentioned thermal printer, with a layer 3 containing a heat-melting material.
is provided on a relatively thin heat-resistant support layer 4, such as thin paper or heat-resistant plastic film. Here, heat-melting materials are materials that do not exhibit a liquid state themselves at room temperature, but melt at a temperature of about 50 to 150 degrees Celsius and exhibit the characteristics of printing ink, such as wax, mineral oil, vegetable oil, etc. Added carbon black, basic pigment, oleic acid, etc. to 80-100℃
It is coated on a heat-resistant support layer such as paper at a temperature of . This printing tape will not exhibit any printing effect even if it is brought into contact with recording paper at room temperature. As shown in FIGS. 4, 5, and 6, the printing tape 2 is brought into close contact with the recording paper 5, and the support layer 4 is
Place the thermal head 1 on the surface.

The above-described transfer type thermal printer prints on a recording medium as follows.

When the thermal head 1 is selectively heated and presses the recording medium through the printing tape, the printing tape in contact with the heating element of the thermal head is locally heated, and the solid ink 3 adhering to the area is heated. is locally melted, and the melted ink adheres to the transfer paper 5 as shown in FIG. 6, 6', completing printing on the plain paper. When the heating by the thermal head stops, the molten ink 6 adhering to the transfer paper is cooled again and becomes solid ink. Therefore, the thermal transfer type thermal printer solves the above-mentioned storage problem (1), and also improves (2) the problem of reheating, and (3) the problem of requiring a special recording medium. Ru. However, in the thermal transfer method, printing tape coated with solid ink is more expensive than thermal paper, which is disadvantageous when printing in large quantities.

An embodiment of a thermal printer according to the present invention will be described below.

In the embodiments described below, storage stability and tamperability are not a big problem, and when printing in large quantities, printing is performed on thermal paper, and printing on official documents or other archival or plain paper is required. In that case,
The present invention provides a thermal printer that can perform printing using a thermal transfer method using the same printer.

In the embodiments described below, first, the printer is configured to be able to perform printing using both printing methods, and in order to use different thermal head driving conditions for thermal paper and printing tape, the pulse applied voltage or pulse width to the thermal head is changed. It is configured so that you can choose.

Further, since the thermal transfer method requires a printing tape, a structure is provided to prevent the above-mentioned printing tape from being squeezed between the thermal paper and the thermal head when printing on thermal paper. This is because the optimal electrical conditions for thermal paper, such as the time when electricity is applied to the thermal head, are
If thermal transfer printing is performed under conditions such as 8 ms and 8 ms pauses, the mylar film used for the support member will melt, causing the mylar film to stick to the thermal head, which may lead to thermal head failure. This is because it is considered to be a cause and the print quality may also deteriorate.

An embodiment of a thermal printer according to the present invention will be described below with reference to the drawings.

FIG. 7 is a perspective view showing an embodiment of a thermal printer according to the present invention. In the figure, reference numeral 11 denotes a base (carriage), a holding member 12 for the thermal head, and reels 14 and 1 on which a printing tape 13 is wound.
5. A lever member 16 and a pulse motor 17 for moving the printing tape 13 up and down are mounted on the rail 1.
8 Move left and right on top.

FIG. 8 is an enlarged view of the base 11 shown in FIG. 7, in which the driving of the lever member 16 is illustrated in detail. The pulse motor 17 transmits its rotational motion to the eccentric cam 19, and the linear motion obtained by the eccentric cam 19 is transmitted to one end of the lever member 16, and the holding portion 20 of the printing tape 13 provided at the other end causes vertical motion. Let's do it.

When the holding member 12 is viewed from the direction a in FIG. 7, it appears as shown in FIG. 9. The holding member 12 is made of a thermally conductive material such as aluminum, and a groove 20 is provided in a part of the holding member 12, and a base body 22 made of ceramic or the like on which a thermal head 21 is mounted is fixed to the groove 20 with an adhesive or the like. The holding member 12 is a screw 2
3, 24, etc., and a cord 25 for applying an electric signal to the thermal head 21 extends downward along the groove 20. The thermal head 21 may be made of any material as long as heating elements are arranged in a matrix on the same plane and the heating elements can be selectively driven. For example, it may be made of electrically insulating material such as glass. A plurality of heat generating resistors and an electric conductor for supplying power to the heat generating resistors are provided on a substrate having a flat surface and a smooth surface, so that a necessary thermal pattern can be obtained according to the information to be recorded. The heating resistor is configured to generate heat by passing an electric current through the corresponding heating resistor through an electric conductor.Borides such as zirconium, hafnium, chromium, lanthanum, tungsten, molybdenum, niobium, tantalum, and titanium are sputtered. Or thin film made by vacuum beam evaporation method, Ta ₂ N
A material selected from sputtering film, nichrome vapor deposited film, SnO ₂ film, etc. can be used.

As shown in FIG. 7, the printing tape is mounted on a base 11, and the reel 15 for sending out the printing tape 13 is rotatably fixed to the base 11. Reel 1 for winding tape
4, the base 11 moves on the rail 18 in the right direction (arrow b
When the base 11 moves in the direction of winding the printing tape 13 (in the direction of arrow d), and when the base 11 moves to the left on the rail 18 (in the opposite direction of arrow b) is constructed such that a gear 26 fixed to its rotating shaft meshes with a gear plate 27 via a one-way clutch so as to stop the winding of the printing tape 13.

FIG. 10 is an exploded perspective view showing the portion related to printing tape winding to show the above-mentioned take-up reel 14 in more detail, and FIG. 11 is an assembled sectional view. The base 11 has a pinion 2 as shown in FIGS. 10 and 11.
6, this pinion 26 has a fixed rack 2
It always meshes with 7. Since a one-way clutch 28 using a conventionally known roller or spring is included inside the pinion, the shaft 29 rotates in response to the rotational movement of the pinion 26 in the direction of the arrow shown in FIG. Spring 30, which is mounted so as not to rotate relative to 29, also rotates. The spring 30 provides rotational force to the printing tape reel 14. However, if a load greater than the frictional force between the reel 14 and the spring 30 is applied to the printing tape 13, the reel 14 can slip against the spring 30. In addition, when there is no load applied to the printing tape, even if the diameter of the tape wound on the reel is the smallest, the setting is such that the momentum of the tape fed per one movement of the cartridge is greater than the momentum of the cartridge. There is. The base 11 on which the thermal head and printing tape are placed is slidably fixed on the rail 18, and both ends of the rail 18 are rotatably fixed to the side plates 31 and 32. At the same time, a gear plate 27 is installed parallel to the rail 18.
are arranged and fixed by fixing plates 33 and 34, so that the gear 26 and the gear plate 27 are always in mesh with each other. Between the side plates 33 and 34, a roller 35 for changing the running angle of the recording paper is rotatably fixed, and a paper feed roller 36 is rotatably fixed, and is further held along the movement position of the thermal head. The holding material 37 is arranged and its ends are fixed on both side plates, and an elastic member 38 such as rubber or felt is pasted and fixed onto the holding material. A recording paper 39 to be recorded by the thermal head is wound around a paper feed roller 36 and then placed between the elastic member 38 and the thermal head. Reference numeral 40 indicates a paper feed motor, which includes a pulley 41 provided on the motor and a pulley 4 provided on the paper feed roller 36.
A belt 43 is wound between the recording paper 2 and the recording paper 2, so that the recording paper can be moved in one direction by driving a paper feed motor. Reference numeral 44 indicates a pulse motor for moving the base, and a wire 47 is connected between a pulley 45 fixed to the rotating shaft of the motor 44 and a pulley 46 rotatably provided on a part of the side plate 31. By winding the wire and fixing a part of the wire to the base 11, the base 11 is configured to move on the rail 18 when the pulse motor 44 rotates.

A spring 48 is fixed between the end of the gear plate 27 and an arm extending from the side plate 32 to pull the gear plate 27 upward, and a plunger 49 is fixed to the end. By driving the plunger, the gear plate 27 is pulled down against the spring 48. Therefore, when the plunger 49 is not driven,
Since the rail 18 is driven counterclockwise, the thermal head is pressed against the recording paper via the printing tape.

To describe the above-mentioned printing tape 13 in detail, this printing tape (print member) is a heat-resistant support layer made of a thin film of several microns to several tens of microns made of an adhesive resin with a low melting temperature that melts when heat is applied. It is something that has been established.

Next, the drive circuit for the thermal head 21 and the pulse motor 17 will be explained.

FIG. 12 shows the generation of an instruction signal for printing on thermal paper or by transferring ink from a printing tape to a recording medium. SW1, SW
2 and SW3 are switches, only one of which is always on. Alternatively, a rotary switch or a slide switch may be used.

The switch SW1 is operated to be turned on when printing on thermal paper.

The switch SW2 is operated when printing is performed by transferring ink from the printing tape onto a recording medium. The switch SW3 is operated when ink from the printing tape is transferred to a recording medium and printing is performed.

FIG. 13 shows a circuit for storing the operated switches SW1 to SW3 and the next operated switch. F1 to F3 are flip-flops, which are set when switches SW1 to SW3 are turned on.
A signal of 1 is output from outputs Q ₁ to _{Q 3} . Flip-flops F1 to F3 are reset by the output of a counter to be described later, and 0 signals are output from outputs _Q1 to _Q3 .

FIG. 14 shows a control circuit that generates the rotation direction and rotation drive signal of the pulse motor 17.

AG1 to AG4 are AND gates, switch SW
1 to SW3 signals and flip-flops F1 to F3
The signals are applied in pairs.

OG1 and OG2 are OR gates, and as shown in the figure, the outputs of AND gates AG1 and AG2 and AND gate AG
3 and the output of AG4 are respectively applied.
CNT is a counter that receives activation of switches SW1 to SW3 via OR gate OG3, outputs a train of eight pulses from terminal CO, and outputs signal CNT8 corresponding to the eighth pulse from terminal C1.
A signal corresponding to the eighth pulse is obtained by decoding the contents of the counter. counter CNT
The pulse train is applied to AND gates AG5 and AG6 together with the outputs of OR gates OG1 and OG2.

The above AND gates AG5 and AG6 are OR gates.
Opened by output from OG1 and OG2, counter
Outputs CNT pulse train. The number of pulses in such a pulse train is determined by the pulse motor.
Here, we use a pulse motor that rotates 15 degrees with one pulse, and because the pulse motor creates three states during one rotation, one pulse train
One pulse train is 8 to obtain a rotational movement of 120°.
It consists of several pulses.

FIG. 15 shows a pulse motor and its drive circuit. In the figure, DC is a drive circuit which generates a drive signal for driving the pulse motor 1 in response to the outputs of AND gates AG5 and AG6. Such a drive circuit
As the DC, Shinko Tsushin Kogyo's SDB520 IC can be used.
To further explain this drive circuit DC,
The terminal CW is a terminal to which a pulse train is applied to rotate the pulse motor clockwise, and the terminal CCW is a terminal to which a pulse train is applied to rotate the pulse motor counterclockwise. Signals that respond to pulses applied from terminals CW and CCW are terminals φ ₁ , φ ₂ , φ ₃ , φ ₄
More can be obtained. D is a driver that amplifies the signal from the drive circuit DC and drives the pulse motor to rotate.

FIG. 16 shows a drive switching control circuit for the thermal head.

AG7 and AG8 are AND gates and switch SW
It opens and closes with signals from 1 to SW3, and the signals shown in Figure 17
The thermal head 21 is driven by T ₁ and T ₂ via an OR gate OG4 and an AND gate AG9 which is opened and closed in response to a print command signal P. Signal T ₁ is a signal waveform when printing on thermal paper and has a width of 8 ms, and signal T ₂ is a signal waveform when transferring ink from a printing tape to a recording medium and has a width of 4 ms.

The operation of the embodiment having the above configuration will be explained.

The lever L shown in FIG. 7 is moved to I as shown in FIG.
20, the switch SW3 is on, and the pulse motor 17 is in the state shown in FIG. The current operation of the circuit system is that the output _Q3 of the flip-flop F3 is "1", and the signal SW
3 becomes "1". Therefore, since the control circuit shown in FIG. 14 does not output the signals CW and CCW, the pulse motor 17 is stopped and the current state is maintained.
In the thermal head 21, as shown in FIG. 16, the AND gate AG8 is opened and the signal T2 is connected to the AND gate.
The print signal P is applied via AG8, OR gate DG4, and AND gate AG9. Therefore, the first
As shown in FIG. 9 on the printing tape, the upper ink is selected, and the characters transferred with this ink are transferred onto the recording medium.

If you wish to print with ink of a different color on the printing tape 13, move the lever L to the position.
By operating the lever L, the switch SW2 is turned on and the switch SW3 is turned off. Therefore, flip-flop F is turned on by turning on switch SW2.
Since the flip-flop F3 shown in FIG _{. 13 holds its output Q 3 at} "1", the AND gate shown in FIG.
AG4 sets its output to “1” and OR gate OG2
is applied to the AND gate AG6 through the switch
Counter CNT started by turning on SW2 outputs eight pulse trains from terminal CO, and these eight
The pulse train is applied to the terminal CCW of the drive circuit DC via the AND gate AG6, and the pulse motor rotates counterclockwise. A pulse motor rotates 15 degrees with one pulse and 120 degrees with eight pulses. The rotation of the pulse motor rotates the eccentric cam 19, and the second
The lever member 16 shown in FIG.
1 makes it possible to transfer. Also, once at the last pulse of the pulse train, the flip-flop F1-F
3 is reset, but flip-flop F2 is set again by turning on switch SW2.
In this state, when the print command P is applied to the AND gate AG9 shown in FIG.
Since the AND gate AG8 is open due to the ON of SW2, the signal T2 is applied to the thermal head 21 through the AND gate AG9 via the AND gate AG8 and the OR gate OG4. Therefore, even if the thermal head 21 presses the recording paper through the printing ribbon 13, the ink can be transferred to the recording paper without melting the base material of the printing ribbon 13.

Next, the case of printing on thermal paper will be explained.

First, assume that thermal paper is loaded in place of recording paper. Next, when the lever L is shifted to the position,
The switch SW1 is turned on and the output _Q1 of the flip-flop F1 becomes "1". Flip-flop F2 still keeps its output _Q2 at "1". Therefore, the AND gate AG3 in FIG. 14 satisfies the input condition and sends the 8 pulses of the counter CNT to the terminal of the drive circuit DC via the AND gate AG6.
Apply CCW and turn the pulse motor counterclockwise 120
degree, and as shown in FIG. 21, the printing tape 13 is transferred to the thermal head 21 by rotating the eccentric cam.
and thermal paper. Also switch SW1
When T is turned on, AND gate AG7 in FIG. 16 is opened, and signal T1 is applied to the thermal head. Flip-flop F2 is reset by the signal at terminal _C1 in the same way as before.

Therefore, when a printing command is applied to the device manually or from a processor, the thermal head is driven at the timing of the signal T1, so the thermal paper pressed by the thermal head receives sufficient thermal energy and the printing is thermally sensitive. done on paper. Now, assuming that printing is to be performed on plain paper again, when the lever L is moved to the position, the switch SW2 is turned on, and the AND gate AG1 satisfies the input condition and outputs 1. Therefore, the counter CNT outputs a pulse train from the AND gate AG5, and the drive circuit
Apply a pulse to the DC terminal CW to rotate the pulse motor clockwise.

Therefore, the eccentric cam 17 changes from the state shown in FIG.
In the state shown in FIG. 0, the printing tape is placed between the thermal head and the recording medium, and the thermal head is driven by the signal T2 when the AND gate AG8 is opened.

When lever L is returned to position I, the printing tape and thermal head are controlled in the same manner as described above.

As described above, according to the thermal printer according to the present invention, since it is possible to selectively record on a heat-sensitive sheet or a recording sheet, it is possible to perform optimal recording according to the application.

[Brief explanation of the drawing]

Figure 1 is an external view of a thermal head to explain a conventional recording device, Figure 2 is a diagram showing an example of printing by the recording device shown in Figure 1, Figure 3 is a cross-sectional view of a printing tape, and Figure 4 is a diagram showing an example of printing by the recording device shown in Figure 1. 5 and 6 are cross-sectional views of the printing tape when printing on recording paper using the printing tape, FIG. 7 is a perspective view of the thermal printer according to the present invention, and FIG. 8 is shown in FIG. FIG. 9 is an enlarged perspective view of the base, FIG. 9 is a perspective view of the thermal head provided on the base, FIG. 10 is an exploded perspective view of the bobbin attachment mechanism provided on the base, and FIG. 11 is the bobbin attachment mechanism. 12 is a printing method selection instruction circuit diagram, Figure 13 is a circuit diagram, Figure 14 is a pulse motor control circuit diagram, Figure 15 is a pulse motor drive circuit diagram, and Figure 16 is a thermal head drive circuit. Figure, 1st
Figure 7 is a signal waveform diagram, Figure 18 is a side view of the base, Figure 19 is an enlarged perspective view of the printing tape, Figure 20 is a side view of the base, Figure 21 is a side view of the base, 16... Lever members, AG1 to AG6...and gate, AG7 to AG9...and gate.

Claims (1)

[Scope of Claims] 1. A loading section for interchangeably loading a recording sheet and a heat-sensitive sheet; a thermal head having a heating element and provided opposite to the loading section; and the loading section. in either an active position where it is sandwiched between the thermal head and a retracted position where it is not sandwiched between the loading section and the thermal head;
a printing tape holding means that can switchably hold a printing tape having ink; and a thermal recording energizing pulse and the pulse applied to the thermal head so that an image can be recorded on a recording sheet or a thermal sheet loaded in the loading section. means for switching to selectively apply to the thermal head a current pulse for thermal transfer recording that generates a smaller amount of heat than the amount of heat generated by applying it to the thermal head; and a first means for instructing recording on the recording sheet.
command signal selection means for selectively generating a signal and a second signal instructing recording on the heat-sensitive sheet; and the printing tape holding means positions the printing tape at the retracted position in response to the second signal. ,
The switching means selects the energizing pulse for thermal transfer recording, and the printing tape holding means positions the printing tape at the operating position in response to the first signal, and the switching means selects the energization pulse for thermal transfer recording. A thermal printer configured to select energizing pulses and capable of recording images on both the recording sheet and the heat-sensitive sheet.