KR890005898Y1 - Controll system for ink-jet of ink-jet printer - Google Patents

Controll system for ink-jet of ink-jet printer Download PDF

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Publication number
KR890005898Y1
KR890005898Y1 KR2019850017005U KR850017005U KR890005898Y1 KR 890005898 Y1 KR890005898 Y1 KR 890005898Y1 KR 2019850017005 U KR2019850017005 U KR 2019850017005U KR 850017005 U KR850017005 U KR 850017005U KR 890005898 Y1 KR890005898 Y1 KR 890005898Y1
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South Korea
Prior art keywords
ink
ink jet
voltage
piezoelectric element
jet head
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KR2019850017005U
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Korean (ko)
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KR870009854U (en
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이근춘
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주식회사금성사
허신구
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/015—Ink jet characterised by the jet generation process
    • B41J2/04—Ink jet characterised by the jet generation process generating single droplets or particles on demand
    • B41J2/045—Ink jet characterised by the jet generation process generating single droplets or particles on demand by pressure, e.g. electromechanical transducers
    • B41J2/04501—Control methods or devices therefor, e.g. driver circuits, control circuits
    • B41J2/04581—Control methods or devices therefor, e.g. driver circuits, control circuits controlling heads based on piezoelectric elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
    • B41J2/01—Ink jet
    • B41J2/07—Ink jet characterised by jet control

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  • Particle Formation And Scattering Control In Inkjet Printers (AREA)

Abstract

내용 없음.No content.

Description

잉크제트 프린터의 잉크분사 제어회로Ink injection control circuit of ink jet printer

제1도는 일반적인 잉크제트 헤드의 개략단면도.1 is a schematic cross-sectional view of a general ink jet head.

제2도는 본 고안의 잉크분사 제어회로도.2 is an ink injection control circuit diagram of the present invention.

제3도는 제2도의 각부의 파형도.3 is a waveform diagram of each part of FIG.

* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings

5 : 압전소자 7 : 구동부5 piezoelectric element 7 drive unit

8 : 진동분검출부 9 : 필터8: vibration detection part 9: filter

10 : 정류부 11 : 비교부10: rectifying unit 11: comparison unit

본 고안은 잉크제트 헤드로 잉크를 분사시키면서 인자하는 잉크제트 프린터에 있어서, 잉크제트 헤드의 잉크분사를 제어하는 회로에 관한 것으로, 특히 잉크제트 헤드의 잉크실내에 기포가 발생되거나 잉크가 완전히 충전되지 않으면 잉크제트헤드의 동작을 정지시키게 한 잉크제트 프린터의 잉크분사 제어회로에 관한 것이다.The present invention relates to a circuit for controlling ink injection of an ink jet head in an ink jet printer which prints while injecting ink into the ink jet head, and in particular, bubbles are not generated or ink is completely filled in the ink chamber of the ink jet head. And an ink jet control circuit of the ink jet printer which causes the operation of the ink jet head to be stopped.

일반적으로 잉크제트 프린터에서 잉크를 분사하는 잉크제트 헤드는 제1도에 도시한 바와 같이, 헤드본체(1)의 중간부에 잉크가 충전되는 잉크실(2)을 형성하여 그 잉크실(2)의 전방에는 잉크를 분사하는 노즐(3)을 형성하고, 후방에는 진동판(4) 및 압전소자(5)를 부착하여, 그 잉크실(2)에는 잉크를 공급하는 잉크공급관(6)이 연결되어 있다.In general, an ink jet head for ejecting ink from an ink jet printer forms an ink chamber 2 filled with ink in the middle of the head body 1, as shown in FIG. A nozzle 3 for ejecting ink is formed in front of the nozzle, and a diaphragm 4 and a piezoelectric element 5 are attached to the rear thereof, and an ink supply pipe 6 for supplying ink is connected to the ink chamber 2. have.

이와 같이된 잉크제트 헤드는 압전소자(5)에 구동펄스 전압이 인가되면 압전소자(5)가 변위되면서 진동판(4)을 진동시키고, 그 진동판(4)의 진동에 따라 잉크실(2)내의 압력이 증진되어 잉크실(2)내에 충전되어 있는 잉크가 노즐(3)을 통해 전방으로 분사되며, 노즐(3)을 통해 분사된 잉크의 양이 잉크공급관(6)을 통해 잉크실(2)로 유입되어 재중전되는데, 이때 잉크실(2)내에 잉크가 완전히 재충전 되지 않거나 또는 잉크가 재충전되면서 잉크실(2)내에 기포가 발생되면, 노즐(3)을 통해 잉크가 균일하게 분사되지 못하여 인가 상태가 균일하게 되지 못하게 되나, 종래의 잉크제트 프린터에서는 잉크실(2)내에 잉크가 완전히 충전되어 있지 않거나 기포의 발생에 관계없이 압전소자(5)에 구동펄스전압을 인가하여 인자를 계속하였으므로 인자상태가 균일하게 되지 못하는 결함이 있었다.The ink jet head as described above vibrates the diaphragm 4 while the piezoelectric element 5 is displaced when a driving pulse voltage is applied to the piezoelectric element 5. The ink jet head vibrates in the ink chamber 2 according to the vibration of the diaphragm 4. The pressure is increased so that the ink filled in the ink chamber 2 is ejected forward through the nozzle 3, and the amount of ink ejected through the nozzle 3 is transferred through the ink supply pipe 6 to the ink chamber 2. When ink is not completely refilled in the ink chamber 2 or bubbles are generated in the ink chamber 2 while the ink is refilled, the ink is not uniformly sprayed through the nozzle 3 and applied. The state becomes uneven, but in the conventional ink jet printer, printing is continued by applying a driving pulse voltage to the piezoelectric element 5 regardless of whether the ink is not completely filled in the ink chamber 2 or bubbles are generated. The condition becomes uniform It was not faulty.

본 고안은 이와 같은 종래의 결함을 감안하여, 잉크제트 헤드의 잉크실(2)내에 잉크가 완전히 충전되어 있지 않거나 또는 기포가 발생되면, 압전소자(5)의 동작을 정지시켜 인자가 중지되게 안출한 것으로, 이를 첨부된 제2도 및 제3도의 도면에 의하여 상히 설명하면 다음과 같다.In view of such a conventional defect, the present invention, when ink is not completely filled in the ink chamber 2 of the ink jet head or bubbles are generated, the operation of the piezoelectric element 5 is stopped and the printing is stopped. If one, it will be described differently by the accompanying drawings of Figures 2 and 3 as follows.

제2도는 본 고안의 잉크분사 제어회로도로서, 이에 도시한 바와 같이 잉크제트 헤드의 제어부(도면에 도시하지 않았음)에 접속된 구동펄수전압 입력단자(A)를 인버터(I1)를 통해 트랜지스터(TR1)의 베이스에 접속하여 그의 콜렉터를 저항(R1) 및 트랜지스터(TR2)의 베이스에 접속하고, 트랜지스터(TR2)의 에미터는 저항(R2)에 접속함과 아울러 그 접속점을 저항(R3)을 통해 압전소자(5)에 접속하여 구동부(7)를 구성하고, 구동부(7)의 저항(R3) 및 압전소자(5)의 접속점은 정전압 다이오드(ZD1)를 통해 가변저항(VR1)에 접속하여 진동분검출부(8)를 구성하며, 진동분검출부(8)의 가변저항(VR1) 가변단자는 콘덴서(C1)를 통해 저항(R4)에 접속하여 필터(9)를 구성하는 한편, 필터(9)의 콘덴서(C1)와 저항(R4)의 접속점은 다이오드(D2)를 통해 콘덴서(C2)에 접속하여 정류부(10)를 구성하고, 정류부(10)의 다이오드(D1)와 콘덴서(C2)의 접속점은 저항(R5) 및 비교(COM1)의 비반전입력단자(+)에 접속하고, 비교기(COM1)의 반전입력단자(-)에는 일측단자가 전원단자(Vcc)에 접속된 가변저항(VR2)의 가변단자를 접속하여 비교부(11)를 구성하며, 상기 비교부(11)의 비교기(COM1) 출력단자를 상기 잉크제트 헤드의 제어부에 접속하여 구성한 것으로, 상기에서 비교기(COM1)의 출력단자에 고전위신호가 출력되어 잉크제트헤드의 제어부에 인가될때 그 잉크제트헤드의 제어부에서 구동펄스 전압이 출력되지 않게 되어 있다.2 is an ink injection control circuit diagram of the present invention, and as shown therein, a drive pulse voltage input terminal A connected to a control unit (not shown) of an ink jet head is connected to a transistor (I1) through an inverter I1. It is connected to the base of TR1 and its collector is connected to the base of the resistor R1 and the transistor TR2, and the emitter of the transistor TR2 is connected to the resistor R2 and the connection point is connected through the resistor R3. The drive unit 7 is formed by connecting to the piezoelectric element 5, and the connection point of the resistor R3 and the piezoelectric element 5 of the drive unit 7 is connected to the variable resistor VR1 through the constant voltage diode ZD1 to vibrate. The powder detector 8 is configured, and the variable resistor VR1 of the vibration powder detector 8 is connected to the resistor R4 through the capacitor C1 to configure the filter 9, while the filter 9 Connection point of the capacitor C1 and the resistor R4 is connected to the capacitor C2 through the diode D2 to form the rectifying unit 10. The connection point of the diode D1 and the capacitor C2 of the rectifier 10 is connected to the resistor R5 and the non-inverting input terminal (+) of the comparison COM1, and the inverting input terminal of the comparator COM1 (-). ) Is connected to the variable terminal of the variable resistor (VR2) connected to the power supply terminal (Vcc) to form a comparator (11), the output terminal of the comparator (COM1) of the comparator 11 is the ink jet When the high potential signal is output to the output terminal of the comparator COM1 and is applied to the control section of the ink jet head, the driving pulse voltage is not output from the control section of the ink jet head.

이와 같이 구성된 본 고안의 잉크 분사 제어회로의 작용효과를 상세히 설명하면 다음과 같다.Referring to the effect of the ink injection control circuit of the present invention configured as described above in detail.

전원단자(Vcc)에 전원이 인가되고, 잉크제트헤드의 제어부에서 고전위의 구동펄스 전압이 출력되어 구동펄스전압 입력단자(A)에 입력되면, 그 고전위의 구동펄스전압은 인버터(I1)를 통해 저전위신호로 반전되어 트랜지스터(TR1)의 베이스에 인가되므로 그 트랜지스터(TR1)가 오프되고, 이에따라 트랜지스터(TR2)의 베이스에 고전위신호가 인가되어 온 되므로 전원단자(Vcc)의 전원이 그 트랜지스터(TR2) 및 저항(R3)을 통해 압전소자(5)에 인가되어 압전소자(5)가 변위된다.When power is applied to the power supply terminal Vcc, and a high potential drive pulse voltage is output from the controller of the ink jet head and input to the drive pulse voltage input terminal A, the drive pulse voltage of the high potential is inverter I1. The transistor TR1 is turned off because it is inverted into a low potential signal and applied to the base of the transistor TR1. Accordingly, the high potential signal is applied to the base of the transistor TR2. Thus, the power supply of the power supply terminal Vcc is turned off. The piezoelectric element 5 is displaced by being applied to the piezoelectric element 5 through the transistor TR2 and the resistor R3.

따라서, 압전소자(5)의 변위에 따라 진동판(4)이 진동되어 잉크실(2)의 압력이 증대되므로 잉크실(2)내에 충전되어 있던 잉크가 노즐(3)을 통해 분사된다.Therefore, the diaphragm 4 vibrates with the displacement of the piezoelectric element 5, and the pressure of the ink chamber 2 increases, so that the ink filled in the ink chamber 2 is injected through the nozzle 3.

그리고 잉크제트 헤드의 제어부에서 구동펄스전압이 출력되지 않아 구동펄스 전압 입력단자(A)에 저전위신호가 입력되며, 그 저전위신호는 인버터(I1)를 통해 고전위신호 반전되어 트랜지스터(TR1)의 베이스에 인가되므로 상기와는 반대로 트랜지스터(TR1)가 온되고, 트랜지스터(TR2)가 오프되어 압전소자(5)에 인가되는 전원이 차단되고, 이에따라 압전소자(5)가 원상복귀되어 진동판(4)의 진동이 정지되며 잉크실(2)에는 잉크공급관(6)을 통해 잉크가 재유입된다.In addition, since the driving pulse voltage is not output from the controller of the ink jet head, the low potential signal is inputted to the driving pulse voltage input terminal A. The low potential signal is inverted by the high potential signal through the inverter I1 to invert the transistor TR1. In contrast to the above, the transistor TR1 is turned on, the transistor TR2 is turned off, and the power applied to the piezoelectric element 5 is cut off. Accordingly, the piezoelectric element 5 is returned to its original state to vibrate the diaphragm 4. ) Is stopped, and ink is reflowed into the ink chamber 2 through the ink supply pipe 6.

즉, 구동펄스전압 입력단자(A)에 구동펄스전압이 인가됨에 따라 압전소자(5)가 변위되고, 진동판(4)이 진동되어 잉크실(2)의 잉크가 분사된 후 다시 잉크실(2)내에 잉크가 유입된다.That is, as the driving pulse voltage is applied to the driving pulse voltage input terminal A, the piezoelectric element 5 is displaced, the diaphragm 4 is vibrated, the ink of the ink chamber 2 is ejected, and then the ink chamber 2 Ink flows into the inside).

한편, 이와 같이 잉크실(2)의 잉크가 분사된 후 잉크 공급관(6)을 통해 잉크가 유입되면서 잉크가 완전히 충전되고, 또한 기포가 발생되지 않으면, 압소자(5)에 인가된 전압이 제3(a)도에 도시한 바와 같이 고전위상태를 계속 유지되게되고, 이에 따라 진동분검출부(8)에 의해 검출되는 전압이 없게되므로 필터(9) 및 정류부(10)를 통해 비교부(11)의 비교기(COM1) 비반전입력단자(+)에 인가되는 전압도 없게되어 비교기(COM1)의 출력측에는 저전위신호가 출력되고, 이 저전위신호는 잉크제트 헤드의 제어부에 인가되므로 그 제어부에서 구동펄스전압이 발생되어 출력될수 있게 된다.On the other hand, when the ink in the ink chamber 2 is injected, the ink flows in through the ink supply pipe 6 to completely fill the ink, and if no bubbles are generated, the voltage applied to the pressure element 5 is reduced. As shown in FIG. 3 (a), the high potential state is continuously maintained, and thus there is no voltage detected by the vibration powder detector 8, and thus the comparison unit 11 is provided through the filter 9 and the rectifier 10. There is no voltage applied to the non-inverting input terminal (+) of the comparator (COM1), and a low potential signal is output to the output side of the comparator (COM1), and this low potential signal is applied to the control part of the ink jet head. The driving pulse voltage is generated and can be output.

그리고 시간(t1)에 잉크실(2)내에 잉크가 완전히 충전되지 않거나 잉크실(2)내에 기포가 발생하면, 제3(a)도에 도시한 바와 같이 압전소자(5)에 인가된 고전위가 진동하게 되고, 그 진동된 전압은 진동분검출부(8)에 의해 제3(b)도에 도시한 바와 같이 검출된 후 필터(9)를 통해 제3(c)도에 도시한 바와 같이 필터링 되며, 정류부(10)를 통해 제3(d)도에 도시한 바와 같이 정류되어 비교기(COM1)의 비반전입력단자(+)에 비교전압으로 인가된다.If the ink is not completely filled in the ink chamber 2 or bubbles are generated in the ink chamber 2 at time t1, the high potential applied to the piezoelectric element 5 as shown in FIG. Is vibrated, and the vibrated voltage is detected by the vibration detection unit 8 as shown in FIG. 3 (b) and then filtered through the filter 9 as shown in FIG. 3 (c). The rectifier 10 is rectified as shown in FIG. 3 (d) and applied to the non-inverting input terminal (+) of the comparator COM1 as a comparison voltage.

따라서, 이때 가변저항(VR2)에 전원단자(Vcc)에 인가된 전압이 분할되어 비교기(COM1)의 반전입력단자(-)에 인가되는 기준전압보다 그의 비반전입력단자(+)에 인가되는 전압이 높게되어 그의 출력단자에 고전위신호가 출력되고 이 고전위신호는 잉크제트헤드의 제어부에 인가되므로 그 제어부에서 구동펄스전압이 출력되지 않아 구동펄스전압 입력단자(A)에 저전위신호가 인가된다. 따라서, 상기의 설명에서와 같이 구동부(7)의 트랜지스터(TR1)는 온되고, 트랜지스터(TR2)는 오프되어 압전소자(5)의 구동을 정지시키게 된다. 이후 시간이 경과됨에 따라 정류부(10)의 콘덴서(C2) 충전전압이 비교기(COM1)의 반전입력단자(-)에 인가되는 전압이하로 방전되게되면 비교기(COM1)에서 저전위신호가 출력되며, 따라서 이때 잉크제트 헤드의 제어부에서 고전위의 구동펄스전압이 출력되어 구동펄스전압 입력단자(A)에 인가될 수 있게된다.Therefore, at this time, the voltage applied to the power supply terminal Vcc is divided into the variable resistor VR2 and the voltage applied to the non-inverting input terminal (+) than the reference voltage applied to the inverting input terminal (-) of the comparator COM1. The high potential signal is outputted to the output terminal thereof, and the high potential signal is applied to the control unit of the ink jet head. Therefore, the driving pulse voltage is not output from the control unit so that the low potential signal is applied to the drive pulse voltage input terminal A. do. Therefore, as described above, the transistor TR1 of the driving unit 7 is turned on and the transistor TR2 is turned off to stop the driving of the piezoelectric element 5. Then, as time passes, when the charge voltage of the capacitor C2 of the rectifier 10 is discharged below the voltage applied to the inverting input terminal (-) of the comparator COM1, the low potential signal is output from the comparator COM1. Therefore, the driving pulse voltage of high potential is output from the controller of the ink jet head so that the driving pulse voltage can be applied to the driving pulse voltage input terminal A. FIG.

이상에서 상세히 설명한 바와 같이 본 고안은 잉크제트 헤드의 잉크실(2)내에 잉크가 완전히 충전되지 않거나 또는 기포가 발생될 경우에는 압전소자의 구동을 중지시켜 잉크제트 헤드에서 잉크가 분사되지 않게하므로 인자가 불균일하게 되는 등의 결함을 제거할 수 있는 효과가 있다.As described in detail above, the present invention stops driving of the piezoelectric element when ink is not completely filled in the ink chamber 2 of the ink jet head or bubbles are generated so that ink is not ejected from the ink jet head. There is an effect that can eliminate defects such as unevenness.

Claims (1)

잉크제트 헤드의 제어부에서 발생되는 구동펄스전압에 의해 구동부(7)의 압전소자(5)에 전압을 인가하여 잉크를 분사하는 잉크제트 프린터에 있어서, 상기 압전소자(5)에 인가된 전압의 진동분을 검출하는 진동분검출부(8)와, 상기 진동분검출부(8)에서 출력되어 필터(9)를 통한 전압을 정류하는 정류부(10)와 상기 정류부(10)의 출력전압과 기준전압을 비교하여 그 비교결과를 상기 잉크제트헤드의 제어부에 인가하는 비교부(11)로 구성함을 특징으로 하는 잉크제트 프린터의 잉크분사 제어회로.In an ink jet printer in which ink is applied by applying a voltage to the piezoelectric element 5 of the driving unit 7 by a driving pulse voltage generated by the control unit of the ink jet head, vibration of the voltage applied to the piezoelectric element 5 is applied. Compare the output voltage and the reference voltage of the vibration powder detector 8 for detecting powder, the rectifier 10 outputted from the vibration powder detector 8 to rectify the voltage through the filter 9 and the rectifier 10. And a comparison section (11) for applying the comparison result to the control section of the ink jet head.
KR2019850017005U 1985-12-17 1985-12-17 Controll system for ink-jet of ink-jet printer KR890005898Y1 (en)

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