US3596276A - Ink jet printer with droplet phase control means - Google Patents

Ink jet printer with droplet phase control means Download PDF

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Publication number
US3596276A
US3596276A US798052A US3596276DA US3596276A US 3596276 A US3596276 A US 3596276A US 798052 A US798052 A US 798052A US 3596276D A US3596276D A US 3596276DA US 3596276 A US3596276 A US 3596276A
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United States
Prior art keywords
phase
charging
drop
droplets
forming unit
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Expired - Lifetime
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US798052A
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English (en)
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Kenneth T Lovelady
Robert B Mcjohnson
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Recognition Equipment Inc
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Recognition Equipment Inc
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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
    • B41J2/07—Ink jet characterised by jet control
    • B41J2/115—Ink jet characterised by jet control synchronising the droplet separation and charging time

Definitions

  • a charging voltage applied to ink droplets [1.8. CI 346/1, discharged from the nozzle of an ink-jet printer is controlled 346/75 by varying the phase of the charging voltage placed upon a Int. Cl ..G01d 18/00 droplet in dependence upon the time-phase relationship Field of Search 346/75, 1 between the droplet and the charging voltage REFERENCE ACCUMULATOR VOLTAGE CLOCK "'i P l 2 a '30?
  • the time-phase relationship of the charging voltage and the instant at which the droplets break off from the ink stream is critical. Due to variations in the physical properties of the ink, such as viscosity and conductivity, and because of environmental changes in the equipment such as temperature, the time-phase relationship can change drastically, degrading the resultant printing operation. Therefore, because the breakoff instant of the droplets from the ink stream may vary, there exists a need for compensation therefor.
  • the time-phase relationship between the breakoff instant of the ink droplets and the chargingvoltage to be placed on the droplets is detected and controlled by varying the charging voltage through a servo loop system responsive to variations in the time-phase relationship.
  • a charging voltage is applied to the charging plates for charging ink droplets which pass therebetween.
  • the droplet path impinges the path of a traveling document.
  • the droplets do not impinge the document during a phase control cycle, but, rather, are collected in 'an ink catcher.
  • a phase control system is connected to the ink catcher for detecting the voltage on the catcher created upon capture of charged ink droplets.
  • the catcher-voltage is compared to a reference voltage in a phase control system to determine the time-phase relationship of the droplet breakoff instant and the charging voltage.
  • the phase control servo will vary the phase of the charging voltage so as to position the charging voltage waveform in the correct time relation with respect to the droplet breakoff instant.
  • FIG. 1 illustrates the invention where droplets are electrostatically charged and deflected
  • FIG. 2 is a time plot of the droplet charging voltage
  • FIG. 3 is a time plot of the droplet charging voltage used during the phase-control cycle
  • FIG. 4 illustrates a bar print when the proper time-phase relation exists
  • FIG. 5 illustrates a bar print when an improper time-phase relation exists.
  • a document 100 travels along a line and direction indicated by the arrow 101.
  • lnk-jet printer 10 as indicated by arrow 102, is askew to the direction of document travel.
  • Ink jet printer comprises a slender conduit or tube 103 through which ink or other suitable writing fluid is fed under pressure.
  • the ink passes through a nozzle or conduit 104 which is under control of a suitable high frequency, low amplitude vibrator, such as a piezoelectric crystal.
  • Piezoelectric crystal 105 energized by alternating current from source 331 by way of channel 332 imparts the desired high speed vibration to the nozzle or conduit 104, a suitable frequency is of the order of 48 kilocycles per second.
  • the nozzle 104 terminates in a tip 107 having a small orifice of, for example, about 0.001 inch diameter.
  • a very fine stream of writing fluid is forced from supply 120 by pump 121 through tip 107.
  • the high frequency vibration of nozzle 104 causes the flow of fluid from tip 107 to be broken into very small or fine droplets as indicated by the broken stream 108.
  • a signal voltage from a generator 319 is connected by output channel 328 to two spaced charging plates 109 between which the train of droplets passes.
  • the signal voltage from generators 319 may be varied to deflect the droplets to print bars such as bars 114 on document 100. More particularly, as the droplets fall by gravity or are propelled under suitable pressure or force as applied to nozzle 104, they pass through an electrostatic field created by applying a voltage from source 115 to two spaced deflection plates 110 and 111.
  • Uncharged ink droplets are not affected by the electrostatic field between plates 110 and 111. They flow or fall without deflection into a catcher 112 which is insulated from plate 110. Catcher 112 may be drained through tube 113. Thus, if no charge is carried by a droplet, it does not land on document 100. However, upon application of a signal voltage to the charging plates 109, the droplets are charged. As the signal voltage increases droplets are each more highly charged. Deflection by the electrostatic field between plates 110 and 111 as they fall on the document increases with increased charge.
  • the droplet charging voltage normally applied to plates 109 preferably has the form shown in FIG. 2. It is a stair step voltage synchronized with the sinewave voltage applied to vibrator from generator 331. It is necessary that the droplets employed for forming bars such as bars 114, FIG. 1, leave tip 107 and travel toward document 100 with the charges thereon represented by the levels on the stair step function 150. More particularly, the first droplet 151 in a representative system would have a charge thereon represented by the 200 volt field 152 between plates and 111. The second droplet 153 would have a lower charge represented by the lower voltage 154 on plates 109. The charging voltage is measured relative to the ground potential at which nozzle 104 is maintained.
  • droplet 153 may not pass between plates 109 while plates have charge 154 thereon. Rather, it may break away at a later time, namely the time when the voltage on plates 109 relative to tip 107 is changing from level 154 to level 155. When this is the case, the droplet may have a charge thereon which is any value which may be represented by the difference between the voltages 154 and 155, FIG. 2.
  • the present invention provides for detection of variations in the instant the droplet is formed and the phase of the sinewave voltage from generator 331 so that is will be assured that the charges on the droplets will be represented by the successive levels on the stair step function 150.
  • the system includes a line 300 leading from the catcher 112 to the input of a phase detector 301.
  • the phase detector 301 has an input amplifier 302 the second input of which is supplied by way of channel 303 from a reference voltage source 304.
  • the output of amplifier 302 is connected by way of channel 305 to an analog-to-digital converter 306.
  • the analogtodigital converter has two outputs 307 and 308 which lead to an accumulator 309.
  • An accumulator clock 310 is connected by way of channel 311 to the accumulator 309.
  • Output 312 of accumulator 309 is connected by way of a digital-to-analog converter 313 whose output is connected by way of channel 314 to a phase-shifting unit 315.
  • a system clock 316 is connected by way of channel 317 to the phase-shifter 315 and by way of channel 318 to the sinewave generator 331.
  • the clock pulses from source 316 pass through phase shifter 315 and are applied by way of channel 330 to a drop counter 321 in the function generator 319.
  • the output of drop counter 321 is connected by way of channel 322 to a stair step function generator 323 and by way of channel 334 to a ramp function generator 335.
  • the generator 323 is connected to a gated output amplifier 326 by way of channel 324.
  • the output channel 328 leads to plates 109.
  • the ramp function generator 335 is connected by way of channel 325 to a gated output amplifier 327 whose output is connected by way of channel 329 to channels 328.
  • the printing on document 100 is conducted under the control of a control unit such as a computer 336.
  • a control unit such as a computer 336.
  • write gates in the form of a change in state of control voltage 156, FIG. 2 are applied to amplifier 326 by way of channel 337 so that the stair step function generated by the unit 323 is applied to the plates 109.
  • the write gate on channel 337 is removed and a calibrate gate 157, FIG. 3, is applied to amplifier 327 by way of channel 338 so that a predetermined number of cycles of the ramp function 158 will be applied to the plates 109.
  • the charges on successive droplets impinging the catcher 112 are sensed and employed to adjust the phase shift of the system clock pulses applied to the phase-shift unit 315.
  • the phase will be adjusted so that the droplets will be formed and pass between plates 109 at precise intervals synchronized with the voltage from generator 331.
  • such intervals will be maintained within limit 159, FIG. 2. In such case, they pass between plates 109 during time intervals represented by the treads" on the steps of function 150 rather than on the riser.”
  • clock 316 applies a high frequency clock signal (for example, 48 kilocycles by way of channel 318 to sinewave generator 331.
  • Generator 331 thus provides a synchronized 48 kilocycle sinewave which is applied by way of channel 332 as the crystal excitation voltage to crystal 105.
  • Clock 316 also applies a 48 kilocycle drop clock signal by way of channel 317 to phase-shift unit 315, the operation of which will be described later.
  • Phase-shift unit 315 applies a delayed 48 kilocycle drop clock signal by way of channel 330 to function generator 319.
  • function generator 319 provides a positive charging voltage to the charging plates 109 when bars are to be printed.
  • the charging voltage will be zero and the charging plates 109 will be at zero potential, thus allowing all drops to pass to the ink catcher 112.
  • the clock signal on channel 330 is applied to drop counter 321.
  • Drop counter 321 applies a bar rate through channel 322 to stairstep generator 323.
  • counter 321 was a 3- stage, divide-by-two counter having 3 output lines for output pulses which were applied, one pulse per drop, to generator 323.
  • Generator 323 is a digital-to-analog converter that generates a stairstep voltage level, one level for each of eight pulses from counter 321 per bar, thus producing bars of eight drops each.
  • the stairstep output is applies through channels 324 to write amplifier 326 whose output is a stairstep waveform such as shown in FIG. 2.
  • each bar to be printed computer 336 applies a print command signal through channel 337 to amplifier 326.
  • Amplifier 326 applies the stairstep charging voltage through channel 328 to the charging plates 109.
  • the voltage is held for a period of approximately 20.8 microseconds at each step in order capacitively to charge each droplet at the instant it breaks off from the ink-jet stream.
  • the charging voltage decreases finite voltage increments properly to charge each of the droplets in the bar. After each droplet has been charged it is individually deflected by the field between plates and 111 in direct proportion to the applied charge on the droplet.
  • Gating for amplifier 326 may be from suitable control device such as a digital or analog computer.
  • a control unit 336 Control unit is enabled when a document is in transit past the printing station. Documents may be sensed by unit 339 which is connected to control unit 336 by channel 340.
  • a voltage state as from a source 341 is applied to amplifier 326 by way of an AND gate 342 which energizes the control line 337.
  • movement of a tape 343 through a reader portion of control unit 336 will produce control states on line 344 in accordance with the set 345 which corresponds with bars 114, 1140 and 11%.
  • the present invention prevents deterioration of the bars by providing phase control to correct any change in the timephase relationship between the droplet breakoff point and the charging voltage.
  • phase-control system employs a servo loop to change the delay in the synch signal passing from clock 316 to counter 321 by way of the phase-shift unit 315.
  • This phase-control system operates between documents so that normal printing operations are not affected.
  • the phasecontrol operational period is hereinafter referred to as the calibration period.
  • the bar rate signal output of drop counter 321 is also applied by way of channel 334 to ramp generator 335.
  • Generator 335 when enabled, converts the bar rate signal to a sawtooth waveform and applies the sawtooth signal by way of channel 325 to a calibration amplifier 327.
  • control unit 336 applies a calibration command instruction through AND gate 348 and channel 338 to amplifier 327.
  • Amplifier 327 then applies a sawtooth charging voltage by way of channel 329 to charging plates 109. The sawtooth voltage serves as the drop charging voltage during the calibration period.
  • the charging voltage or calibrate waveform is shown in FIG. 3.
  • This negative calibrate waveform changes from zero to about -200 volts and capacitively charges each drop with a positive charge.
  • the drops apply a positive potential to catcher 112.
  • the charged droplets are analogous to an electrical current since they constitute the movement of charges past a given point in a given time interval.
  • Catcher 112 is isolated from electrical ground and insulated from plate 110.
  • the voltage created on catcher 112 as a result of collection of the charged droplets is applied through channel 300 to phase. detector 301 wherein it the droplet breakoff point to the charging is compared by amplifier 302 to a reference voltage.
  • a reference voltage of approximately 200 millivol'ts has been found to be satisfactory, the same being produced on channel 303 by unit 304.
  • the reference voltage may be selected to represent the desired phase relationship of voltage. If the voltages on lines 300 and 303 are not equal, the resulting error voltage is amplified and applied by wayof channel 305 to analog-to-digital converter 306. If the error voltage indicates a high condition, converter 306 generates an up" phase error voltage signal on output channel 307. Conversely, a low condition causes converter 306 to generate a down" phase error voltage signal on output channel 308.
  • phase error voltages on channels 307 and 308 are applied to accumulator 309.
  • Accumulator 309 is a seven-bit, up-
  • down counter used as an integrator or loop filter in a servo loop.
  • a clock pulse fromthe accumulator clock 310 is applied by-way of-channel (311 to accumulator 309.
  • accumulator 309 causes the updown counter to increase up or down one phase detector 301. The accumulator increments only during the calibration period between documents.
  • the sign'al from the accumulator 309 is applied over chan nel 312 .to'digital-to-analog converter 313 which converts the stored error voltage to a phase-control voltage on channel 314.
  • Channel 314 applies the phase-control voltage to phaseshift'unit 315.
  • Phase-shift unit'315 controls the phase delay between the charging voltage output'of generator 319 and the crystal excitation voltage output of generator 331. This phase delay is controlled by thephase error voltage signal from converter 313. If an error is detected by phase detector 301'between the voltage applied to catcher l1'2during the calibrate period and the reference voltage of generator 304, the resulting phase error voltage produced in converter 313 applied to phase-shift unit 315 automatically to delay. the 48 kc. drop clock signal output of phase-control unit 315 to the function generator 3l9.-Phase-shift unit 315 controls the time-phase relationship between the charging waveform to charging plates 109 and the breakoff point of ink droplets emerging from nozzle 107.
  • the method of compensating for variation in the time-phase relation between a periodic driving function and resultant drop 7 formation which comprises:
  • a system for compensating for variations in the timephas'e relation between a periodically actuated drop forming unit and the instant of drop formation by said unit in an electrostaticallydeflected ink jet printer which comprises:
  • n v e. a phase shift unit for adjusting the phase of said stair step functions relative to said drop forming unit in response to prior variations in charges on said droplets due to said second means.
  • phase shift unit connected to said catcher for adjusting the phase of said stair step functions relative to said drop forming unit in response to prior variations in charges on said droplets due to said second means.

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  • Particle Formation And Scattering Control In Inkjet Printers (AREA)
  • Fax Reproducing Arrangements (AREA)
  • Ink Jet (AREA)
US798052A 1969-02-10 1969-02-10 Ink jet printer with droplet phase control means Expired - Lifetime US3596276A (en)

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US79805269A 1969-02-10 1969-02-10

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US (1) US3596276A (enrdf_load_stackoverflow)
JP (1) JPS5014496B1 (enrdf_load_stackoverflow)
FR (1) FR2033968A5 (enrdf_load_stackoverflow)
GB (1) GB1278976A (enrdf_load_stackoverflow)
NL (1) NL165412C (enrdf_load_stackoverflow)
NO (1) NO128184B (enrdf_load_stackoverflow)
SE (1) SE350863B (enrdf_load_stackoverflow)

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3681778A (en) * 1971-05-03 1972-08-01 Dick Co Ab Phasing of ink drop charging
US3761941A (en) * 1972-10-13 1973-09-25 Mead Corp Phase control for a drop generating and charging system
JPS48101024A (enrdf_load_stackoverflow) * 1972-03-31 1973-12-20
US3787881A (en) * 1972-09-18 1974-01-22 Mead Corp Apparatus and method for bar code printing
JPS4952540A (enrdf_load_stackoverflow) * 1972-06-27 1974-05-22
DE2360013A1 (de) * 1972-12-11 1974-06-12 Ibm Digitale phasensteuerung fuer einen tintenstrahldrucker
DE2362415A1 (de) * 1972-12-29 1974-07-04 Ibm Tintenstrahldrucker
JPS4971813A (enrdf_load_stackoverflow) * 1972-09-25 1974-07-11
JPS4996632A (enrdf_load_stackoverflow) * 1973-01-17 1974-09-12
US3852772A (en) * 1971-09-03 1974-12-03 Recognition Equipment Inc Mechanically cycled ink jet printer
US3866237A (en) * 1973-06-22 1975-02-11 Ibm Digital phase control for ink jet printer
US3875574A (en) * 1974-01-14 1975-04-01 Dick Co Ab Method for improving performance of an ink jet bar code printer
US3889271A (en) * 1972-12-01 1975-06-10 Agfa Gevaert Ag Ink jet process utilizing novel dyes
US3898673A (en) * 1972-05-15 1975-08-05 Ibm Phase control for ink jet printer
US3972052A (en) * 1972-10-24 1976-07-27 Oki Electric Industry Company, Ltd. Compensation apparatus for high speed dot printer
US3981019A (en) * 1973-09-26 1976-09-14 Nippon Telegraph And Telephone Public Corporation Charging signal supply circuit for ink jet system printer
US3999188A (en) * 1973-12-05 1976-12-21 Hitachi, Ltd. Ink-jet recording apparatus
US4012745A (en) * 1975-11-28 1977-03-15 Burroughs Corporation Phase correction system
US4024511A (en) * 1975-09-25 1977-05-17 Recognition Equipment Incorporated Modified biphase modulation bar code printer
US4025926A (en) * 1973-01-17 1977-05-24 Sharp Kabushiki Kaisha Phase synchronization for ink jet system printer
US4051485A (en) * 1972-10-24 1977-09-27 Oki Electric Industry Company, Ltd. Printing apparatus
US4060813A (en) * 1975-03-17 1977-11-29 Hitachi, Ltd. Ink drop writing apparatus
US4063253A (en) * 1975-03-10 1977-12-13 Hitachi, Ltd. Ink jet recording apparatus
DE2749669A1 (de) * 1976-12-16 1978-06-22 Ibm Tintenstrahl-matrixdrucker
US4249187A (en) * 1978-04-24 1981-02-03 Bell & Howell Company Ink jet printer with deflected nozzles
US4258370A (en) * 1979-05-04 1981-03-24 The Mead Corporation Jet drop printer
WO1981003306A1 (en) * 1980-05-16 1981-11-26 Commw Scient Ind Res Org Density control of jet printing droplets
DE3107767A1 (de) * 1980-02-28 1982-02-04 Ricoh Co., Ltd., Tokyo Farbstrahldrucker
US4470052A (en) * 1981-04-10 1984-09-04 Recognition Equipment Incorporated A-C Coupled, modulator based, phase-error sensing for IJP
EP0098056A3 (en) * 1982-06-25 1985-12-27 EASTMAN KODAK COMPANY (a New Jersey corporation) Ink jet printer control circuit and method
US4616234A (en) * 1985-08-15 1986-10-07 Eastman Kodak Company Simultaneous phase detection and adjustment of multi-jet printer
WO1989000504A1 (en) * 1987-07-20 1989-01-26 Hertz Carl H Method and apparatus for ink jet recording
US4812673A (en) * 1987-07-17 1989-03-14 Burlington Industries, Inc. Print pulse control circuit for electrostatic fluid jet applicator
US6334678B1 (en) 1999-09-01 2002-01-01 International Paper Company Method for applying chemical watermarks on substrate
US20050122381A1 (en) * 2002-01-28 2005-06-09 Thierry Golombat Converging axis dual-nozzled print head and printer fitted therewith
US20050206675A1 (en) * 2004-03-17 2005-09-22 Levin Alexander M Ink jet print head cleaning system
US20070064037A1 (en) * 2005-09-16 2007-03-22 Hawkins Gilbert A Ink jet break-off length measurement apparatus and method
EP3017288A4 (en) * 2013-08-16 2017-07-19 Bio-rad Laboratories, Inc. Timing and/or phase adjustment of the separation and/or charging of drops from a fluid stream in a flow cytometer
CN113484531A (zh) * 2021-06-30 2021-10-08 中国热带农业科学院橡胶研究所 一种橡胶树排胶自动监测系统及方法

Cited By (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3681778A (en) * 1971-05-03 1972-08-01 Dick Co Ab Phasing of ink drop charging
US3852772A (en) * 1971-09-03 1974-12-03 Recognition Equipment Inc Mechanically cycled ink jet printer
JPS48101024A (enrdf_load_stackoverflow) * 1972-03-31 1973-12-20
US3898673A (en) * 1972-05-15 1975-08-05 Ibm Phase control for ink jet printer
JPS4952540A (enrdf_load_stackoverflow) * 1972-06-27 1974-05-22
US3787881A (en) * 1972-09-18 1974-01-22 Mead Corp Apparatus and method for bar code printing
JPS4971813A (enrdf_load_stackoverflow) * 1972-09-25 1974-07-11
US3761941A (en) * 1972-10-13 1973-09-25 Mead Corp Phase control for a drop generating and charging system
US4051485A (en) * 1972-10-24 1977-09-27 Oki Electric Industry Company, Ltd. Printing apparatus
US3972052A (en) * 1972-10-24 1976-07-27 Oki Electric Industry Company, Ltd. Compensation apparatus for high speed dot printer
US3889271A (en) * 1972-12-01 1975-06-10 Agfa Gevaert Ag Ink jet process utilizing novel dyes
DE2360013A1 (de) * 1972-12-11 1974-06-12 Ibm Digitale phasensteuerung fuer einen tintenstrahldrucker
DE2362415A1 (de) * 1972-12-29 1974-07-04 Ibm Tintenstrahldrucker
US4025926A (en) * 1973-01-17 1977-05-24 Sharp Kabushiki Kaisha Phase synchronization for ink jet system printer
JPS4996632A (enrdf_load_stackoverflow) * 1973-01-17 1974-09-12
US3866237A (en) * 1973-06-22 1975-02-11 Ibm Digital phase control for ink jet printer
US3981019A (en) * 1973-09-26 1976-09-14 Nippon Telegraph And Telephone Public Corporation Charging signal supply circuit for ink jet system printer
US3999188A (en) * 1973-12-05 1976-12-21 Hitachi, Ltd. Ink-jet recording apparatus
US3875574A (en) * 1974-01-14 1975-04-01 Dick Co Ab Method for improving performance of an ink jet bar code printer
US4063253A (en) * 1975-03-10 1977-12-13 Hitachi, Ltd. Ink jet recording apparatus
US4060813A (en) * 1975-03-17 1977-11-29 Hitachi, Ltd. Ink drop writing apparatus
US4024511A (en) * 1975-09-25 1977-05-17 Recognition Equipment Incorporated Modified biphase modulation bar code printer
US4012745A (en) * 1975-11-28 1977-03-15 Burroughs Corporation Phase correction system
DE2749669A1 (de) * 1976-12-16 1978-06-22 Ibm Tintenstrahl-matrixdrucker
US4249187A (en) * 1978-04-24 1981-02-03 Bell & Howell Company Ink jet printer with deflected nozzles
US4258370A (en) * 1979-05-04 1981-03-24 The Mead Corporation Jet drop printer
DE3107767A1 (de) * 1980-02-28 1982-02-04 Ricoh Co., Ltd., Tokyo Farbstrahldrucker
WO1981003306A1 (en) * 1980-05-16 1981-11-26 Commw Scient Ind Res Org Density control of jet printing droplets
US4470052A (en) * 1981-04-10 1984-09-04 Recognition Equipment Incorporated A-C Coupled, modulator based, phase-error sensing for IJP
EP0098056A3 (en) * 1982-06-25 1985-12-27 EASTMAN KODAK COMPANY (a New Jersey corporation) Ink jet printer control circuit and method
US4616234A (en) * 1985-08-15 1986-10-07 Eastman Kodak Company Simultaneous phase detection and adjustment of multi-jet printer
US4812673A (en) * 1987-07-17 1989-03-14 Burlington Industries, Inc. Print pulse control circuit for electrostatic fluid jet applicator
WO1989000504A1 (en) * 1987-07-20 1989-01-26 Hertz Carl H Method and apparatus for ink jet recording
US6334678B1 (en) 1999-09-01 2002-01-01 International Paper Company Method for applying chemical watermarks on substrate
US20050122381A1 (en) * 2002-01-28 2005-06-09 Thierry Golombat Converging axis dual-nozzled print head and printer fitted therewith
US7175263B2 (en) * 2002-01-28 2007-02-13 Imaje Sa Converging axis dual-nozzled print head and printer fitted therewith
US20050206675A1 (en) * 2004-03-17 2005-09-22 Levin Alexander M Ink jet print head cleaning system
US7128410B2 (en) * 2004-03-17 2006-10-31 Videojet Technologies Inc. Ink jet print head cleaning system
US20070064037A1 (en) * 2005-09-16 2007-03-22 Hawkins Gilbert A Ink jet break-off length measurement apparatus and method
US7434919B2 (en) * 2005-09-16 2008-10-14 Eastman Kodak Company Ink jet break-off length measurement apparatus and method
US20090027459A1 (en) * 2005-09-16 2009-01-29 Hawkins Gilbert A Ink jet break-off length measurement apparatus and method
US8226199B2 (en) * 2005-09-16 2012-07-24 Eastman Kodak Company Ink jet break-off length measurement apparatus and method
EP3017288A4 (en) * 2013-08-16 2017-07-19 Bio-rad Laboratories, Inc. Timing and/or phase adjustment of the separation and/or charging of drops from a fluid stream in a flow cytometer
US10126225B2 (en) 2013-08-16 2018-11-13 Bio-Rad Laboratories, Inc. Timing and/or phase adjustment of the separation and/or charging of drops from a fluid stream in a flow cytometer
US10451535B2 (en) 2013-08-16 2019-10-22 Bio-Rad Laboratories, Inc. Timing and/or phase adjustment of the separation and/or charging of drops from a fluid stream in a flow cytometer
CN113484531A (zh) * 2021-06-30 2021-10-08 中国热带农业科学院橡胶研究所 一种橡胶树排胶自动监测系统及方法

Also Published As

Publication number Publication date
NL7001887A (enrdf_load_stackoverflow) 1970-08-12
DE1952248B2 (de) 1977-04-21
NL165412C (nl) 1981-04-15
FR2033968A5 (enrdf_load_stackoverflow) 1970-12-04
NO128184B (enrdf_load_stackoverflow) 1973-10-08
JPS5014496B1 (enrdf_load_stackoverflow) 1975-05-28
SE350863B (enrdf_load_stackoverflow) 1972-11-06
DE1952248A1 (de) 1970-09-03
GB1278976A (en) 1972-06-21
NL165412B (nl) 1980-11-17

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