JP2908182B2 - Serial 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 serial printer.

[0002]

2. Description of the Related Art Conventionally, a serial printer which performs printing with a dot type print head has a head drive circuit for driving the print head, and the head drive circuit is provided in a carriage unit. ing. FIG. 2 is a head drive circuit diagram of a conventional serial printer.

[0003] In Figure, A ₁ is the main body portion of a serial printer, A ₂ denotes a carriage unit of the serial printer. The main body A ₁ is and having a platen (not shown) is rotatably supported, a carriage shaft (not shown) parallel to the platen is bridged. Also,
The carriage section A ₂ has a carriage (not shown) movably supported along the carriage shaft,
A print head and an ink ribbon cassette (not shown) are mounted on the carriage.

[0004] The print head has an armature having a print wire fixed to a tip thereof, and the armature is swingably supported by a main body of the print head by a leaf spring. On the other hand, a magnet is provided so as to face the armature, and a permanent magnet generates a magnetic flux to attract the armature to the magnet against the elastic force of the leaf spring.

The magnet has a head coil 10 and a magnetic flux is generated by energizing the head coil 10 through a power supply line 50 to cancel the magnetic flux of the permanent magnet and release the armature. At this time, the printing wire flies and collides with a printing paper (not shown) via the ink ribbon to perform printing. Incidentally, the main body A ₁ has a main control board 11 for controlling the entire serial printer. On the other hand, the carriage section A ₂
Denotes a motor substrate unit 13 for supporting a motor (not shown) for spacing, a print head control signal substrate unit 14 for generating a control signal corresponding to the operation of the print wire, and a print head driver substrate unit 15 for driving the print head. Having. The print head control signal board 14 and the print head driver board 15 are mounted on a print head.

The main control board 11 and the motor board 13 are connected by a flexible cable 16 having flexibility. The main control board section 11 has a power supply section 18, a circuit section 24, and a regenerative circuit 26 for consuming the secondary current from the head driver 21, and a CPU (not shown) of the circuit section 24 includes a carriage section A _Two
, The motor circuit unit 20, the head driver 21 and the like. The regenerative circuit 26 includes a Zener diode Z1 as a constant voltage element for setting a regenerative voltage, a power transistor 28, and a diode 29 for preventing backflow.

Each signal line extending from the main control board section 11 is connected to one end of a flexible cable 16 by a connecting means C ₁ such as a connector or a pressure contact.
6 at the other end the motor substrate unit 1 by the same connecting means C ₂
3 are connected to each signal line. The motor board section 13 has a motor circuit section 20 provided with a motor coil and a sensor (not shown), and has a bypass capacitor 32 connected to the power supply section 18 to absorb electric charge when the power is turned on / off.

The motor board 13, printhead control signal board 14, and printhead driver board 1
5, a special connector member 33 having an integral structure is disposed, and the connector member 33 and the motor substrate 13
The connector member 33 and the print head control signal board 14 and the print head driver board 15 are connected by a card edge connector.

The print head control signal board section 14
Has a control circuit 35 and a sensor 36. The control circuit 35 receives print data and a print control command from the main control board section 11, generates a control signal, and sends the control signal to the print head driver board section 15. In this case, the operation of the print wire for each pin of the print head is detected by the sensor 36, and an optimal control signal corresponding to the operation of the print wire is generated.

The control signal is transmitted to a pair of head drivers 2 of the print head driver board 15 via a connector member 33.
1 is output. The head driver 21 supplies a current so that each head coil 10 is driven for a necessary drive time. Reference numeral 38 denotes a regenerative current line for supplying a secondary raw current, and the secondary raw current passes through the connector member 33, the motor board 13, the connecting means C ₂ , the flexible cable 16 and the connecting means C _1. The regenerative circuit 2
6 and is consumed in the regeneration circuit 26.

Next, the operation of the head driver 21 will be described. FIG. 3 is a circuit diagram of a head driver in a conventional serial printer, and FIG. 4 is a waveform diagram of the head driver in a conventional serial printer. As shown in the figure, the head driver 21 has a control circuit 43, a main switching element 45, a primary switching element 46, and diodes 47 and 48. The control circuit 43 is connected to the print head control signal board section 14 (FIG. 2) via a signal line 44, and receives control signals from the print head control signal board section 14 to turn on / off the signals EN1 and EN2.
When the signal EN1 is turned on, the main switching element 45 is turned on, and when the signal EN2 is turned on, the primary switching element 46 is turned on.

The diode 47 is connected to the power line 5
0 is connected between the main switching element 45, prevents the primary regenerative current i _F flows backward, the diode 48 is connected between the head coil 10 and the regenerative circuit 26, the secondary regenerative current i _Z backflow To prevent In the head driver 21 having the above configuration, the control circuit 43 receives a control signal from the print head control signal
1 and EN2 are turned on, the main switching element 45 and the primary switching element 46 are turned on, and a current i _A is supplied to the head coil 10 by the main switching element 4.
5, a current i flows to drive a magnet (not shown).
Also, at this time, the coil output terminal voltage _VA drops from the power supply voltage E and becomes almost zero. Next, when the signal EN1 is turned off from on, the main switching element 45 is turned off, the current i becomes 0, and the current i _A flowing through the head coil 10 is applied to the primary switching element 46 and the diode 47. As a result, the first-time raw current i _F flows through the power supply line 50 to the head coil 10 again. Also, the coil output terminal voltage _VA decreases to almost the power supply voltage E
Becomes equal to

Incidentally, an armature of a print head (not shown)
When the signal EN1 changes from ON to OFF,
Released from the net, flying the print wire and not shown
Collision with the printing paper (not shown) via the ink ribbon
You. And when the printing wire collides with the printing paper,
Or, before and after that point, the signal EN2 is turned off from on
, The primary switching element 46 is turned off.
And the next-generation raw current i _FBecomes 0. Also, head co
The surplus energy in IL 10 is the secondary raw current i_ZWhen
Through the diode 48 and the regenerative current line 38,
It flows to the raw circuit 26 and is consumed. Carp of this second birth
Output terminal voltage V_AAnd secondary raw voltage V_ZIs the power supply voltage
E is a Zener of the Zener diode Z1 in the regenerative circuit 26.
-Voltage E_ZIs added. Then, the secondary current i
_ZBecomes 0, the coil output terminal voltage V_AAnd second-year students
Voltage V_ZGradually decreases to become equal to the power supply voltage E. This
Like, the armature is attracted to the magnet,
A series of operations ends. Reference numeral 18 denotes a power supply unit.

[0014]

SUMMARY OF THE INVENTION
In conventional serial printers, flexible cables 16
Is disconnected due to fatigue, the inductance of the head coil 10 is reduced.
Back electromotive voltage proportional to the current change rate is generated by the reactance
And the coil output terminal voltage V_AAnd secondary raw voltage V _ZIs a pole
It will be expensive.

Further, since the regenerative current wire 38 is connected by the connector member 33 and the connecting means C ₁ and C ₂ , a contact failure is likely to occur, and if a contact failure occurs, the coil output terminal voltage _VA and the secondary The raw voltage _VZ becomes extremely high. FIG. 5 is a waveform diagram of a coil output terminal voltage and a secondary raw voltage when a contact failure occurs.

If a contact failure occurs in the regenerative current line 38 (FIG. 2), the coil output terminal voltage _VA and the secondary regenerative voltage _VZ become extremely high, as shown in the figure. If the coil output terminal voltage V _A and the secondary raw voltage V _Z exceed the element withstand voltage of the head driver 21, the head driver 21 is destroyed by overvoltage. In addition, a discharge may occur between patterns having a short separation distance and a low withstand voltage, and a circuit of a small signal system such as the control circuit 43 or an element of the sensor 36 may be destroyed.

The present invention solves the above-mentioned problems of the conventional serial printer. When the flexible cable breaks or a contact failure occurs in a regenerative current line connecting the regenerative circuit and the head driver, the coil is removed. A serial driver that prevents the head driver from being damaged by overvoltage due to the output terminal voltage or the secondary raw voltage becoming high, or the discharge occurring between patterns with low withstand voltage, and the elements in small-signal circuits and sensors are not destroyed. It is intended to provide a printer.

[0018]

For this purpose, in a serial printer according to the present invention, a main control board portion provided on a main body portion and a head driver provided on a carriage portion for driving a head coil of a print head. And a head driver board connected to the main control board via a flexible cable.

The main control board includes a regenerative circuit that consumes a secondary regenerative current of the head driver, and the head driver board includes a sub regenerative circuit that consumes a regenerative secondary current of the head driver. Prepare. In another serial printer according to the present invention, a main control board portion provided on a main body portion, a board portion connected to the main control board portion via a flexible cable, and a print head provided on a carriage portion And a head driver board unit connected to the board unit.

The main control board includes a regenerative circuit for consuming the secondary current of the head driver, and the board includes a sub-regenerative circuit for consuming the secondary current of the head driver. In still another serial printer of the present invention, the regenerative circuit and the sub-regenerative circuit each include a constant voltage element, and the secondary regenerative voltage set by the constant voltage element of the sub-regenerative circuit is a constant voltage of the regenerative circuit. It is made higher than the secondary raw voltage set by the voltage element.

[0021]

According to the present invention, as described above, the serial printer includes the main control board portion provided on the main body portion and the head driver provided on the carriage portion for driving the head coil of the print head. And a head driver board connected to the main control board via a flexible cable.

The main control board unit includes a regenerative circuit that consumes a secondary regenerative current of the head driver, and the head driver board unit includes a sub regenerative circuit that consumes a regenerative regenerative current of the head driver. Prepare. In this case, if the flexible cable is disconnected due to fatigue, or if a contact failure occurs in the connection means between the main control board and the flexible cable, a connector between the head driver board and the flexible cable, or the like, the printing is performed. Due to the inductance of the head coil of the head, a back electromotive voltage proportional to the current change rate is generated.

However, since the sub-regenerative circuit is provided, the secondary regenerative current flows through the sub-regenerative circuit, and suppresses an increase in the coil output terminal voltage of the head driver and the secondary regenerative voltage. In another serial printer according to the present invention, a main control board portion provided on a main body portion, a board portion connected to the main control board portion via a flexible cable, and a print head provided on a carriage portion And a head driver board unit connected to the board unit.

The main control board includes a regenerative circuit for consuming the secondary current of the head driver, and the board includes a sub-regenerative circuit for consuming the secondary current of the head driver. In this case, if the flexible cable is disconnected due to fatigue, or if a contact failure occurs in the connection means between the main control board and the flexible cable, a connector between the head driver board and the flexible cable, or the like, the printing is performed. Due to the inductance of the head coil of the head, a back electromotive voltage proportional to the current change rate is generated.

However, since the sub regenerative circuit is provided, the secondary regenerative current flows through the sub regenerative circuit, and suppresses the coil driver terminal voltage of the head driver and the secondary regenerative voltage from increasing. In still another serial printer of the present invention, the regenerative circuit and the sub-regenerative circuit each include a constant voltage element, and the secondary regenerative voltage set by the constant voltage element of the sub-regenerative circuit is a constant voltage of the regenerative circuit. It is made higher than the secondary raw voltage set by the voltage element. In this case, the coil output terminal voltage and the secondary voltage of the head driver can be set to a value obtained by adding the constant voltage by the constant voltage element of the sub regenerative circuit to the power supply voltage.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a circuit diagram of a head driver of a serial printer according to a first embodiment of the present invention, and FIG. 7 is a circuit diagram of a head driver of the serial printer according to the first embodiment of the present invention.

In the drawing, A ₁ is a main body of the serial printer, and A ₂ is a carriage of the serial printer. The main body A ₁ is and having a platen (not shown) is rotatably supported, a carriage shaft (not shown) parallel to the platen is bridged. Also,
The carriage section A ₂ has a carriage (not shown) movably supported along the carriage shaft,
A print head and an ink ribbon cassette (not shown) are mounted on the carriage.

The print head has an armature to which a print wire is fixed at a tip, and the armature is swingably supported by a main body of the print head by a leaf spring. On the other hand, a magnet is provided so as to face the armature, and a permanent magnet generates a magnetic flux to attract the armature to the magnet against the elastic force of the leaf spring.

The magnet has a head coil 10. When the head coil 10 is energized via a power supply line 50, a magnetic flux is generated, and the magnetic flux of the permanent magnet is canceled to release the armature. At this time, the printing wire flies and collides with a printing paper (not shown) via the ink ribbon to perform printing. Incidentally, the main body A ₁ has a main control board 11 for controlling the entire serial printer. On the other hand, the carriage section A ₂
Denotes a motor substrate unit 13 for supporting a motor (not shown) for spacing, a print head control signal substrate unit 14 for generating a control signal corresponding to the operation of the print wire, and a print head driver substrate unit 15 for driving the print head. Having. The print head control signal board 14 and the print head driver board 15 are mounted on a print head.

The main control board 11 and the motor board 13 are connected by a flexible cable 16 having flexibility. The main control board unit 11 includes a power supply unit 18,
A regeneration circuit 59 for consuming the secondary regenerative current i _Z from the circuit portion 24 and the head driver 21,, CPU (not shown) of the circuit 24, the motor circuit unit 20 of the carriage unit A _2, a head driver 21 etc. are controlled. The regenerative circuit 59 includes a Zener diode Z1 as a constant voltage element for setting a regenerative voltage and the power transistor 28.

[0031] Each signal line extending from the main control board 11 is connected to the connector, the connecting means C ₁ of the press or the like to one end of the flexible cable 16, further flexible cable 1
6 at the other end the motor substrate unit 1 by the same connecting means C ₂
3 are connected to each signal line. The motor board section 13 has a motor circuit section 20 provided with a motor coil and a sensor (not shown), and has a bypass capacitor 32 connected to the power supply section 18 to absorb electric charge when the power is turned on / off.

The motor board 13, print head control signal board 14, and print head driver board 1
5, a special connector member 33 having an integral structure is disposed, and the connector member 33 and the motor substrate 13
The connector member 33 and the print head control signal board 14 and the print head driver board 15 are connected by a card edge connector.

The print head control signal board section 14
Has a control circuit 35 and a sensor 36. The control circuit 35 receives print data and a print control command from the main control board section 11, generates a control signal, and sends the control signal to the print head driver board section 15. In this case, the operation of the print wire for each pin of the print head is detected by the sensor 36, and an optimal control signal corresponding to the operation of the print wire is generated.

The control signal is transmitted to the pair of head drivers 2 of the print head driver board 15 through the connector member 33.
1 is output. The head driver 21 supplies a current so that each head coil 10 is driven for a necessary drive time. Further, 38 is a regenerative current line for feeding a secondary regenerative current i _Z, the secondary regenerative current i _Z is the connector member 33, the motor substrate 13, the connection means C _2, flexible cable 16 and the connection means C It flows to the regenerative circuit 59 through ₁ and is consumed in the regenerative circuit 59.

Further, the print head driver board 1
5 is provided with a sub-regenerative circuit 60 in parallel with the regenerative circuit 59. The sub regenerative circuit 60 includes a Zener diode Z2 as a constant voltage element connecting between the regenerative current line 38 and the power supply line 50, and a diode 61 for preventing backflow provided in the regenerative current line 38. The anode of the diode 61 is connected to the diode 4 of the head driver 21.
8 and the cathode of the diode 61 is connected to the cathode of the Zener diode Z2. The value of the Zener voltage E _Z2 of the Zener diode Z2 is larger than the value of the Zener voltage E _Z of the Zener diode Z1 of the regenerative circuit 59.

The diode 6 is connected to the sub-regeneration circuit 60.
Since 1 is provided, a diode is unnecessary in the regenerative circuit 59. The head driver 21 has a control circuit 43, a main switching element 45, a first-generation switching element 46, and diodes 47 and 48. The control circuit 43 is connected to the print head control signal board section 14 via a signal line 44, receives a control signal from the print head control signal board section 14, and turns on the signals EN1 and EN2.
Turn off. When the signal EN1 is turned on, the main switching element 45 is turned on, and when the signal EN2 is turned on, the primary switching element 46 is turned on.

The diode 47 is connected to the power line 5
0 and the main switching element 45 to prevent the primary current i _F from flowing backward. The diode 48 is connected between the head coil 10 and the regenerative circuit 59, and the secondary raw current i _Z flows backward. To prevent Next, the operation of the head driver 21 will be described with reference to FIG.

FIG. 6 is a waveform diagram of a head driver in a serial printer according to an embodiment of the present invention. The normal operation of the head driver 21 is the same as that of the conventional one, and FIG. When the control circuit 43 receives a control signal from the print head control signal board unit 14 and turns on the signals EN1 and EN2, the main switching element 4
5 and the primary life switching element 46 are turned on,
_A current i _A flows through the head coil 10 and a current i flows through the main switching element 45, and drives a magnet (not shown). Also, at this time, the coil output terminal voltage _VA drops from the power supply voltage E and becomes almost zero. Next, when the signal EN1 is turned off from on, the main switching element 45 is turned off, the current i becomes 0, and the current i _A flowing through the head coil 10 is changed to the primary switching element 46.
Then, the current passes through the diode 47 and becomes the first-time raw current i _F, and flows again to the head coil 10 via the power supply line 50. Further, the coil output terminal voltage _VA decreases and becomes substantially equal to the power supply voltage E.

The armature of the print head is released from the magnet when the signal EN1 is turned off from on, and the print wire flies and collides with the print paper via the ink ribbon. Then, when the signal EN2 is turned off from on at or before or after the time when the print wire collides with the printing paper, the primary switching element 46 is turned off, and the primary current i _F becomes 0.
become. Also, the energy surplus in the head coil 10 through the secondary regeneration current i _Z, and the diode 48 and the regenerative current line 38 is consumed flows to the regenerative circuit 59. The secondary regeneration when the coil output terminal voltage V _A and the secondary regenerative voltage V _Z is a value obtained by adding the zener voltage E _Z of the Zener diode Z1 of the power supply voltage E in the regeneration circuit 59. Then, when the secondary raw current _iZ becomes 0, the coil output terminal voltage _VA and the secondary raw voltage _VZ gradually decrease and become equal to the power supply voltage E. In this way, the armature is attracted by the magnet, and a series of operations ends.

By the way, in the regenerative current line 38,
Second-generation raw current i_ZIs the connector member 33, the motor board
Part 13, connection means C_Two, Flexible cable 16 and connecting hand
Stage C ₁And flows to the regenerative circuit 59. And
The cable is not broken and the connector
Material 33, connection means C₁, C_TwoContact failure occurs
If not, the Zener of the Zener diode Z1
Voltage E_ZAnd the Zener voltage E of the Zener diode Z2
_Z2But E_Z<E_Z2 Therefore, the secondary raw current i_ZAre all the regenerative circuits 5
9 and is consumed in the regeneration circuit 59.

Here, if the flexible cable 16 having the above-described structure is disconnected due to fatigue or a contact failure occurs in the connector member 33, the connecting means C ₁ , C _2, etc., the inductance of the head coil 10 causes the current change rate to decrease. A proportional back electromotive voltage is generated. However, since the secondary regenerative circuit 60 is provided in parallel with the regenerative circuit 59 to form a secondary regenerative circuit, the secondary regenerative current i _Z flows through the Zener diode Z2, and the coil output terminal voltage _VA and next raw voltage V _Z is the value obtained by adding the zener voltage E _Z2 of the Zener diode Z2 of the secondary recovery circuit 60 to the power supply voltage E, not more than that high.

[0042] In this case, a Zener voltage E _Z2 is slightly higher than the Zener voltage E _Z. Therefore, flexible cable 1
6 or disconnected by fatigue, zener connector member 33, the connecting means C _1, even contact failure with or generated in C ₂ or the like, the coil output terminal voltage V _A and the secondary regenerative voltage V _Z to the power supply voltage E The value can be a value obtained by adding the voltage _EZ2 .

Therefore, the head driver 21 does not break down due to overvoltage, or the discharge occurs between the patterns having a low withstand voltage, and the circuit of the small signal system such as the control circuit 43 and the elements of the sensor 36 do not break down. Next, a second embodiment of the present invention will be described. FIG. 8 is a head drive circuit diagram of a serial printer showing a second embodiment of the present invention. In the present embodiment, description of items common to the first embodiment will be omitted.

In this case, a sub regenerative circuit 70 is provided on the motor board 13 in parallel with the regenerative circuit 59. The sub-regenerative circuit 70 is composed of a Zener diode Z2 as a constant voltage element connecting between the regenerative current line 38 and the power supply line 50, and a diode 71 for preventing backflow provided in the regenerative current line 38. Then, the anode of the diode 71 is connected to the cathode of the diode 48 (FIG. 7) of the head driver 21, and the cathode of the diode 71 is connected to the cathode of the Zener diode Z2. The value of the Zener voltage E _Z2 of the Zener diode Z2 is larger than the value of the Zener voltage E _Z of the Zener diode Z1 of the regenerative circuit 59.

It should be noted that the diode 7
Since 1 is provided, a diode is unnecessary in the regenerative circuit 59. Therefore, even if the flexible cable 16 is disconnected due to fatigue or a contact failure occurs in the connection means C ₁ , C _2, etc., the coil output terminal voltage V _A
And the secondary voltage V _Z to the power supply voltage E by the Zener voltage E _Z2.
Can be added.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0047]

As described above in detail, according to the present invention, in a serial printer, a main control board portion provided on a main body portion and a head coil of a print head provided on a carriage portion are provided. And a head driver board connected to the main control board via a flexible cable.

The main control board includes a regenerative circuit for consuming the secondary current of the head driver, and the head driver board includes a sub-regenerative circuit for consuming the secondary current of the head driver. Prepare. In this case, if the flexible cable is disconnected due to fatigue, or if a contact failure occurs in the connection means between the main control board and the flexible cable, a connector between the head driver board and the flexible cable, or the like, the printing is performed. A back electromotive voltage proportional to the current change rate is generated by the inductance of the head coil of the head.

However, since the secondary regenerative current flows through the sub regenerative circuit, it is possible to suppress an increase in the coil output terminal voltage of the head driver and the secondary regenerative voltage. Therefore, the head driver does not break down due to overvoltage or the discharge occurs between the patterns having a low withstand voltage, and the element in the circuit or sensor of the small signal system is not broken.

In another serial printer of the present invention, a main control board section provided on the main body section, a board section connected to the main control board section via a flexible cable, and a carriage section are provided. A head driver for driving a head coil of the print head, and a head driver board connected to the board. The main control board unit includes a regenerative circuit that consumes a secondary current of the head driver, and the board unit includes a sub regenerative circuit that consumes a secondary current of the head driver.

In this case, the flexible cable is disconnected due to fatigue, or a contact failure occurs in the connection means between the main control board and the flexible cable, the connector between the head driver board and the flexible cable, and the like. Then, a back electromotive voltage proportional to the current change rate is generated by the inductance of the head coil of the print head. However, since the secondary regenerative current flows through the sub regenerative circuit, it is possible to suppress the coil output terminal voltage of the head driver and the secondary regenerative voltage from increasing.

Therefore, there is no possibility that the head driver is damaged by overvoltage or a discharge is generated between the patterns having a low withstand voltage, and the elements in the circuits and sensors of the small signal system are not damaged. In still another serial printer of the present invention, the regenerative circuit and the sub-regenerative circuit each include a constant voltage element, and a secondary voltage set by the constant voltage element of the sub-regenerative circuit is a constant voltage of the regenerative circuit. It is made higher than the secondary raw voltage set by the voltage element. In this case, the coil output terminal voltage and the secondary voltage of the head driver can be set to a value obtained by adding the constant voltage by the constant voltage element of the sub regenerative circuit to the power supply voltage.

Therefore, there is no possibility that the head driver is damaged by overvoltage or a discharge is generated between patterns having a low withstand voltage, and the elements of the circuits and sensors of the small signal system are not damaged.

[Brief description of the drawings]

FIG. 1 is a head drive circuit diagram of a serial printer showing a first embodiment of the present invention.

FIG. 2 is a head drive circuit diagram of a conventional serial printer.

FIG. 3 is a circuit diagram of a head driver in a conventional serial printer.

FIG. 4 is a waveform diagram of a head driver in a conventional serial printer.

FIG. 5 is a waveform diagram of a coil output terminal voltage and a secondary raw voltage when a contact failure occurs.

FIG. 6 is a waveform diagram of a head driver in the serial printer according to the embodiment of the present invention.

FIG. 7 is a circuit diagram of a head driver in the serial printer according to the first embodiment of the present invention.

FIG. 8 is a head drive circuit diagram of a serial printer showing a second embodiment of the present invention.

[Explanation of symbols]

10 head coil 11 main control board 13 the motor substrate 14 print head control signal substrate section 15 sub-regenerative circuit printhead driver board 16 flexible cable 21 head driver 59 Regenerative circuit 60, 70 A ₁ main body A ₂ carriage unit E _Z , _EZ2 Zener voltage i _F Primary raw current i _Z Secondary raw current _{VA A} coil output terminal voltage V _Z Secondary raw voltage Z1, Z2 Zener diode

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-113567 (JP, A) JP-A-3-128253 (JP, A) JP-A-3-39268 (JP, A) 51140 (JP, A) JP-A-63-254076 (JP, A) JP-A-2-220850 (JP, A) JP-A-63-159060 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41J 2/30

Claims (3)

(57) [Claims] 1. A main control board section provided on a main body section, and (b) a head driver provided on a carriage section for driving a head coil of a print head , and via a flexible cable. as well as have a head driver board portion connected to the main control board, (c) the main control board is provided with a regeneration circuit that consumes secondary regenerative current of the head driver Te, (d) the head driver board unit, a serial printer, characterized in that Ru comprising a sub-recovery circuit that consumes secondary regenerative current of the head driver. (A) a main control board section provided on the main body section; (b) a board section connected to the main control board section via a flexible cable; and (c) a main control board section provided on the carriage section. It is, a head driver for driving the head coil of the print head, and chromatic Then together the head driver board portion connected to the substrate portion
In, (d) the main control board is provided with a regeneration circuit that consumes secondary regenerative current of the head driver, (e) said substrate portion, vice regeneration circuit that consumes secondary regenerative current of the head driver serial printer, characterized in that Ru comprising a. Wherein said regenerative circuit and the sub regeneration circuit comprises a respective <br/> constant voltage element, the secondary regenerative voltage set by the constant-voltage element of the sub-recovery circuit is set by the constant voltage element in the regenerative circuit claim 1 is higher than the secondary regenerative voltage
Or the serial printer according to 2.