JPH05338150A - Driving method for ink jet head - Google Patents

Driving method for ink jet head

Info

Publication number
JPH05338150A
JPH05338150A JP15381392A JP15381392A JPH05338150A JP H05338150 A JPH05338150 A JP H05338150A JP 15381392 A JP15381392 A JP 15381392A JP 15381392 A JP15381392 A JP 15381392A JP H05338150 A JPH05338150 A JP H05338150A
Authority
JP
Japan
Prior art keywords
ink
time
driving
pulse
jet head
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP15381392A
Other languages
Japanese (ja)
Other versions
JP3168699B2 (en
Inventor
Takahiro Usui
隆寛 臼井
Original Assignee
Seiko Epson Corp
セイコーエプソン株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Seiko Epson Corp, セイコーエプソン株式会社 filed Critical Seiko Epson Corp
Priority to JP15381392A priority Critical patent/JP3168699B2/en
Publication of JPH05338150A publication Critical patent/JPH05338150A/en
Application granted granted Critical
Publication of JP3168699B2 publication Critical patent/JP3168699B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Abstract

PURPOSE:To provide a driving method for an ink jet head which enables high speed printing to be carried out by a method wherein a response frequency of an ink jet is raised by returning an ink meniscus quickly to a standard state. CONSTITUTION:In a driving method of an ink jet head wherein a passage and a nozzle surface discharging ink arranged in contact with the passage are provided and a part or the whole of a side wall of the passage is composed of a piezoelectric material, after applying (at time B) an electric pulse discharging an ink drop, an additional pulse being reverse voltage of the electric pulse is applied at time F. Thereby, a response frequency will be raised and high speed printing will be capable of being performed.

Description

【発明の詳細な説明】Detailed Description of the Invention
【0001】[0001]
【産業上の利用分野】本発明はインクジェットヘッドの
駆動方法に関する。更に詳しくは、インク液滴を選択的
に記録媒体に付着させるインクジェットヘッドの駆動方
法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of driving an ink jet head. More specifically, the present invention relates to a method for driving an inkjet head that selectively deposits ink droplets on a recording medium.
【0002】[0002]
【従来の技術】近年インクジェットプリンタは高速印
字、低騒音、高印字品位等の利点から、急速に発展して
いる。インクジェットプリンタに用いられるインクジェ
ットヘッドにはいくつかの方式が提案されているが、一
般的には二つの方式に分けることができる。すなわち第
一の方式は圧電材料を使用して、電気パルスにより圧電
材料を変形させ、インクチャンバーの一部を変形させ
る。そしてインクチャンバー内に圧力パルスを発生さ
せ、この圧力パルスによりノズルからインク滴を吐出さ
せる。第二の方式は発熱抵抗体を使用して、電気パルス
により発熱抵抗体を発熱させる。そしてインクチャンバ
ー内のインクを沸騰させ、蒸気バブルを発生させる。こ
の蒸気バブルにより、ノズルからインク滴を吐出させ
る。
2. Description of the Related Art In recent years, ink jet printers have rapidly developed due to advantages such as high speed printing, low noise, and high printing quality. Several methods have been proposed for an inkjet head used in an inkjet printer, but generally they can be divided into two methods. That is, the first method uses a piezoelectric material and deforms the piezoelectric material by an electric pulse to deform a part of the ink chamber. Then, a pressure pulse is generated in the ink chamber, and an ink droplet is ejected from the nozzle by this pressure pulse. The second method uses a heating resistor and causes the heating resistor to generate heat by an electric pulse. Then, the ink in the ink chamber is boiled to generate a vapor bubble. The vapor bubble causes an ink droplet to be ejected from the nozzle.
【0003】第二の方式は、発熱抵抗体の急速な加熱冷
却を繰り返すために、容易に発熱抵抗体が劣化し、耐久
性に乏しいという課題がある。また蒸気バブルを発生で
きるインクしか使えないという課題もある。これに対し
て第一の方式は前述の課題を持たない。しかしながら第
一の方式はインク滴を吐出するノズル面のインクメニス
カスの安定に長時間を要し、インクジェットヘッド自体
の高速化が困難である。その為、広く普及するには至っ
ていない。
The second method has a problem in that the heating resistor is easily deteriorated due to repeated rapid heating and cooling of the heating resistor, resulting in poor durability. Another problem is that only ink that can generate vapor bubbles can be used. On the other hand, the first method does not have the above-mentioned problems. However, the first method requires a long time to stabilize the ink meniscus on the nozzle surface that ejects ink droplets, and it is difficult to increase the speed of the inkjet head itself. Therefore, it has not reached widespread use.
【0004】第一の方式の課題を解決する方法として、
特開平2−215537号公報に、インク滴を吐出せし
める電気パルスの印加後に、前記電気パルスと同電圧と
なる追加パルスを印加せしめることを特徴とするインク
ジェットヘッドの駆動方法が、提案されている。
As a method for solving the problem of the first method,
Japanese Laid-Open Patent Publication No. 2-215537 proposes a method for driving an inkjet head, which is characterized by applying an additional pulse having the same voltage as the electric pulse after applying the electric pulse for ejecting the ink droplet.
【0005】従来例のインクジェットヘッドの駆動方法
を図3、4を基に説明する。図3は従来例の電圧波形図
である。図4は図3の電圧波形によるインク滴形成とイ
ンクメニスカスの挙動を説明する図である。図3に於て
電気パルスは第1のパルス(以下、メインパルスと呼
ぶ)と同極性の第2のパルス(以下、追加パルスと呼
ぶ)がある。メインパルス1は時刻Aより印加され、追
加パルス2は時刻Eより印加される。次にインク滴形成
とインクメニスカスの挙動を時間を追って図4を用い説
明する。インクメニスカス4は流路(図示せず)に接続
されるノズル3内の外気とのインク形状を呼ぶ。
A method of driving a conventional ink jet head will be described with reference to FIGS. FIG. 3 is a voltage waveform diagram of a conventional example. FIG. 4 is a diagram for explaining the behavior of ink droplet formation and ink meniscus according to the voltage waveform of FIG. In FIG. 3, the electric pulse includes a first pulse (hereinafter referred to as a main pulse) and a second pulse having the same polarity (hereinafter referred to as an additional pulse). The main pulse 1 is applied from time A, and the additional pulse 2 is applied from time E. Next, the behavior of ink droplet formation and ink meniscus will be described with reference to FIG. The ink meniscus 4 refers to the ink shape with the outside air in the nozzle 3 connected to the flow path (not shown).
【0006】(A時刻)インクメニスカス4はA時刻に
於て、直線形状(以下、基準状態と呼ぶ)である。
(Time A) At time A, the ink meniscus 4 has a linear shape (hereinafter referred to as a reference state).
【0007】(B時刻)インクメニスカス4はB時刻に
於て、メインパルスにより流路(図示せず)に与えられ
た圧力パルスにより、凸状の形状になる。
(Time B) At time B, the ink meniscus 4 has a convex shape due to the pressure pulse applied to the flow path (not shown) by the main pulse.
【0008】(C時刻)インクメニスカス4はC時刻に
於て、柱状の形状に成長する。
(Time C) At time C, the ink meniscus 4 grows into a columnar shape.
【0009】(D時刻)インクメニスカス4はD時刻に
於て、ノズル内へ戻る成分と吐出する成分に分離し、く
びれ5が生じる。
(Time D) At time D, the ink meniscus 4 is separated into a component returning to the inside of the nozzle and a component discharging, and a constriction 5 is generated.
【0010】(E時刻)E時刻に於て、くびれ5は成長
し、インク滴6が形成される。
(Time E) At time E, the neck 5 grows and an ink drop 6 is formed.
【0011】(F時刻)インクメニスカス4はF時刻に
於て、インク滴6とインクメニスカス4に分離される。
インクメニスカス4は凹状形状となる。
(Time F) The ink meniscus 4 is separated into ink droplets 6 and ink meniscus 4 at time F.
The ink meniscus 4 has a concave shape.
【0012】(G時刻)インクメニスカス4はG時刻に
於て、凸状形状となる。インクメニスカス4の高さはA
時刻のそれよりも低い。
(G time) The ink meniscus 4 has a convex shape at the G time. The height of the ink meniscus 4 is A
Lower than that of time.
【0013】(H時刻)インクメニスカス4はH時刻に
於て、凹状形状となる。インクメニスカス4の高さはF
時刻のそれよりも低い。
(Time H) The ink meniscus 4 has a concave shape at the time H. The height of the ink meniscus 4 is F
Lower than that of time.
【0014】(I時刻)インクメニスカス4はI時刻に
於て、基準状態に戻る。以降この状態を維持する。
(I time) The ink meniscus 4 returns to the reference state at the I time. This state is maintained thereafter.
【0015】[0015]
【発明が解決しようとする課題】しかしながら、従来例
のインクジェットヘッドの駆動方法は応答周波数が低
い。インクメニスカスは図4のE時刻に示されるインク
メニスカスの状態から、時刻Gのインクメニスカスの状
態になるまでの時間が長くかかるためである。凹状のメ
ニスカスは流路内に圧力パルスがないため、自然振動に
より凹凸の形状を繰り返し、基準状態に戻る。インク吐
出は基準状態で流路に圧力パルス発生させない状態(例
えば時刻Bの凸状のインクメニスカス、時刻Gの凹状の
インクメニスカスの状態)では、実行されない。また実
行されても不安定なインク吐出となる。従って時刻Aに
圧力パルスを印加し、時刻Eにインク滴が形成されて
も、次の圧力パルスは時刻Hまで待たなければならな
い。すなわち応答周波数を高めるためにはインクメニス
カスを速やかに基準状態に戻さなければならない。本発
明はかかる問題を解決するもので、速やかにインクメニ
スカスを基準状態に戻すことによりインクジェットヘッ
ドの応答周波数を高め、高速印字を可能とするインクジ
ェットヘッドの駆動方法を提供することを目的とする。
However, the conventional ink jet head driving method has a low response frequency. This is because the ink meniscus takes a long time from the state of the ink meniscus shown at the time E in FIG. 4 to the state of the ink meniscus at the time G. Since the concave meniscus has no pressure pulse in the flow path, the concave and convex shapes are repeated due to natural vibration to return to the reference state. Ink ejection is not executed in a state where no pressure pulse is generated in the flow path in the standard state (for example, a convex ink meniscus at time B and a concave ink meniscus at time G). Even if it is executed, the ink ejection is unstable. Therefore, even if a pressure pulse is applied at time A and ink droplets are formed at time E, the next pressure pulse must wait until time H. That is, the ink meniscus must be quickly returned to the reference state in order to increase the response frequency. The present invention solves such a problem, and an object of the present invention is to provide a method for driving an inkjet head that promptly returns the ink meniscus to a reference state to increase the response frequency of the inkjet head and enables high-speed printing.
【0016】[0016]
【課題を解決するための手段】本発明のインクジェット
ヘッドの駆動方法はかかる問題を解決するために、イン
ク滴を吐出せしめる電気パルスの印加後に、前記電気パ
ルスの逆極性の追加電気パルスを印加せしめる。
In order to solve such a problem, the method of driving an ink jet head according to the present invention applies an additional electric pulse having a polarity opposite to that of the electric pulse after applying the electric pulse for ejecting an ink droplet. .
【0017】[0017]
【実施例】以下、図を用いて本発明を説明する。The present invention will be described below with reference to the drawings.
【0018】図1は本発明の電圧波形図である。図2は
図1の電圧波形によるインク滴形成とインクメニスカス
の挙動を説明する図である。図1に於て、A時刻にメイ
ンパルス1が印加される。F時刻にメインパルス1と逆
極性の追加パルス2を印加する。
FIG. 1 is a voltage waveform diagram of the present invention. FIG. 2 is a diagram for explaining the behavior of ink droplet formation and ink meniscus according to the voltage waveform of FIG. In FIG. 1, the main pulse 1 is applied at time A. At time F, the main pulse 1 and the additional pulse 2 having the opposite polarity are applied.
【0019】(A時刻)インクメニスカス4はA時刻に
於て、基準状態にある。
(Time A) The ink meniscus 4 is in the standard state at time A.
【0020】(B時刻)インクメニスカス4はB時刻に
於て、メインパルスにより流路(図示せず)に与えられ
た圧力パルスにより、凸状の形状になる。
(Time B) At time B, the ink meniscus 4 has a convex shape due to the pressure pulse applied to the flow path (not shown) by the main pulse.
【0021】(C時刻)インクメニスカス4はC時刻に
於て、柱状の形状に成長する。
(Time C) At time C, the ink meniscus 4 grows into a columnar shape.
【0022】(D時刻)インクメニスカス4はD時刻に
於て、ノズル内へ戻る成分と吐出する成分に分離し、く
びれ5が生じる。
(Time D) At time D, the ink meniscus 4 is separated into a component returning to the inside of the nozzle and a component discharging, and a constriction 5 is generated.
【0023】(E時刻)E時刻に於て、くびれ5は成長
し、インク滴6が形成される。
(Time E) At time E, the neck 5 grows and an ink drop 6 is formed.
【0024】(F時刻)インクメニスカス4はF時刻に
於て、インク滴6とインクメニスカス4に分離される。
インクメニスカス4は基準状態にある。
(Time F) At time F, the ink meniscus 4 is separated into ink droplets 6 and ink meniscus 4.
The ink meniscus 4 is in the reference state.
【0025】(G時刻)インクメニスカス4はG時刻に
於て、凸状形状となる。インクメニスカス4の高さはA
時刻のそれよりも低く、従来例の図4のG時刻のそれよ
りも低い。
(G time) The ink meniscus 4 has a convex shape at the G time. The height of the ink meniscus 4 is A
It is lower than that at time and lower than that at time G in FIG. 4 of the conventional example.
【0026】(H時刻)インクメニスカス4はI時刻に
於て、基準状態に戻る。以降この状態を維持する。
(Time H) The ink meniscus 4 returns to the reference state at time I. This state is maintained thereafter.
【0027】F時刻にインクメニスカス4が基準状態と
なる理由は、逆極性の追加パルスにより、流路内にメイ
ンパルスによる圧力パルスとは逆の圧力パルスが印加さ
れる。この逆圧力パルスにより、インクメニスカス4は
基準状態に戻される。
The reason why the ink meniscus 4 is in the reference state at time F is that a pressure pulse opposite to the pressure pulse of the main pulse is applied in the flow path by the additional pulse of the opposite polarity. The ink meniscus 4 is returned to the reference state by the reverse pressure pulse.
【0028】本発明のインクジェットヘッドの駆動方法
のA時刻からH時刻までの時間(メインパルス印加から
次のメインパルスを印加できるまでの時間)と従来例の
インクジェットヘッドの駆動方法でのA時刻からI時刻
までの時間(メインパルス印加から次のメインパルスを
印加できるまでの時間)を表1に示す。いずれも同じイ
ンクジェットヘッドとインクを用いている。なお本発明
のインクジェットヘッドの駆動方法を適用できるインク
ジェットヘッドは特に限定されるものではなく、圧電材
料を使用して、電気パルスにより圧電材料を変形させ、
インクチャンバーの一部を変形させる。そしてインクチ
ャンバー内に圧力パルスを発生させ、この圧力パルスに
よりノズルからインク滴を吐出せしめるインクジェット
ヘッドであればよい。
From the time from time A to time H of the ink jet head driving method of the present invention (time from application of a main pulse to the time when the next main pulse can be applied) and time A of the conventional ink jet head driving method. Table 1 shows the time until the time I (time from the application of the main pulse to the time when the next main pulse can be applied). Both use the same inkjet head and ink. The ink jet head to which the method for driving the ink jet head of the present invention can be applied is not particularly limited, and a piezoelectric material is used to deform the piezoelectric material by an electric pulse,
Deform a part of the ink chamber. An ink jet head that generates a pressure pulse in the ink chamber and ejects ink droplets from the nozzle by this pressure pulse may be used.
【0029】[0029]
【表1】 [Table 1]
【0030】[0030]
【発明の効果】以上述べてきたように本発明のインクジ
ェットヘッドの駆動方法によれば、インク吐出後のイン
クメニスカスを速やかに基準状態に戻すことにより、イ
ンクジェットヘッドの応答周波数を高め、高速印字を可
能とするインクジェットヘッドを提供できるという優れ
た効果がある。
As described above, according to the method for driving an ink jet head of the present invention, the ink meniscus after ink ejection is quickly returned to the reference state, thereby increasing the response frequency of the ink jet head and performing high speed printing. There is an excellent effect that an ink jet head that can be provided can be provided.
【図面の簡単な説明】[Brief description of drawings]
【図1】本発明のインクジェットヘッドの駆動方法の電
圧波形図。
FIG. 1 is a voltage waveform diagram of a method for driving an inkjet head of the present invention.
【図2】本発明の駆動方法によるインク滴形成とインク
メニスカスの挙動を説明する図。
FIG. 2 is a diagram illustrating the behavior of ink droplet formation and ink meniscus according to the driving method of the present invention.
【図3】従来のインクジェットヘッドの駆動方法の電圧
波形図。
FIG. 3 is a voltage waveform diagram of a conventional inkjet head driving method.
【図4】従来例の駆動方法によるインク滴形成とインク
メニスカスの挙動を説明する図。
FIG. 4 is a diagram for explaining the behavior of ink droplet formation and ink meniscus by a driving method of a conventional example.
【符号の説明】[Explanation of symbols]
1 メインパルス 2 追加パルス 3 ノズル 4 インクメニスカス 5 くびれ 6 インク滴 1 Main pulse 2 Additional pulse 3 Nozzle 4 Ink meniscus 5 Constriction 6 Ink drop

Claims (1)

    【特許請求の範囲】[Claims]
  1. 【請求項1】 流路と前記流路に配接されたインクを吐
    出せしめるノズル面を有し、前記流路の側壁はその一部
    または全体が圧電材料により変形するインクジェットヘ
    ッドの駆動方法に於て、インク滴を吐出せしめる電気パ
    ルスの印加後に、前記電気パルスの逆極性の電圧となる
    追加電気パルスを印加せしめることを特徴とするインク
    ジェットヘッドの駆動方法。
    1. A method for driving an ink jet head, comprising: a flow path; and a nozzle surface disposed in the flow path for ejecting ink, wherein a side wall of the flow path is partially or entirely deformed by a piezoelectric material. Then, after the application of the electric pulse for ejecting the ink droplet, an additional electric pulse having a voltage of the opposite polarity of the electric pulse is applied, and the driving method of the ink jet head.
JP15381392A 1992-06-12 1992-06-12 Driving apparatus for inkjet head and method for driving inkjet head Expired - Lifetime JP3168699B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15381392A JP3168699B2 (en) 1992-06-12 1992-06-12 Driving apparatus for inkjet head and method for driving inkjet head

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15381392A JP3168699B2 (en) 1992-06-12 1992-06-12 Driving apparatus for inkjet head and method for driving inkjet head

Publications (2)

Publication Number Publication Date
JPH05338150A true JPH05338150A (en) 1993-12-21
JP3168699B2 JP3168699B2 (en) 2001-05-21

Family

ID=15570668

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JP3168699B2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0738602A2 (en) * 1995-04-21 1996-10-23 Seiko Epson Corporation Ink jet print head
US6471316B1 (en) 1998-12-09 2002-10-29 Nec Corporation Ink-jet printer in which high speed printing is possible
EP2037510A2 (en) 2007-09-14 2009-03-18 FUJIFILM Corporation Method of driving piezoelectric devices
JP2010179494A (en) * 2009-02-03 2010-08-19 Seiko Epson Corp Liquid discharging apparatus and liquid discharging method
EP2296894A2 (en) * 2008-05-23 2011-03-23 Fujifilm Dimatix, Inc. Method and apparatus to provide variable drop size ejection by dampening pressure inside a pumping chamber
US8186811B2 (en) 2009-12-09 2012-05-29 Samsung Electronics Co., Ltd. Inkjet printing apparatus and method of driving inkjet printing apparatus

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014185142A1 (en) 2013-05-13 2014-11-20 コニカミノルタ株式会社 Inkjet head, method for driving same, and inkjet printer

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0738602A2 (en) * 1995-04-21 1996-10-23 Seiko Epson Corporation Ink jet print head
EP0738602A3 (en) * 1995-04-21 1997-06-11 Seiko Epson Corp Ink jet print head
US6471316B1 (en) 1998-12-09 2002-10-29 Nec Corporation Ink-jet printer in which high speed printing is possible
EP2037510A2 (en) 2007-09-14 2009-03-18 FUJIFILM Corporation Method of driving piezoelectric devices
US7675220B2 (en) 2007-09-14 2010-03-09 Fujifilm Corporation Method of driving piezoelectric devices
EP2296894A2 (en) * 2008-05-23 2011-03-23 Fujifilm Dimatix, Inc. Method and apparatus to provide variable drop size ejection by dampening pressure inside a pumping chamber
EP2296894B1 (en) * 2008-05-23 2020-12-16 Fujifilm Dimatix, Inc. Method and apparatus to provide variable drop size ejection by dampening pressure inside a pumping chamber
JP2010179494A (en) * 2009-02-03 2010-08-19 Seiko Epson Corp Liquid discharging apparatus and liquid discharging method
US8657400B2 (en) 2009-02-03 2014-02-25 Seiko Epson Corporation Liquid discharging apparatus and liquid discharging method
US8186811B2 (en) 2009-12-09 2012-05-29 Samsung Electronics Co., Ltd. Inkjet printing apparatus and method of driving inkjet printing apparatus

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