CA1098161A - Ink jet printing head - Google Patents

Ink jet printing head

Info

Publication number
CA1098161A
CA1098161A CA305,225A CA305225A CA1098161A CA 1098161 A CA1098161 A CA 1098161A CA 305225 A CA305225 A CA 305225A CA 1098161 A CA1098161 A CA 1098161A
Authority
CA
Canada
Prior art keywords
ink
head
head body
ink jet
orifices
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.)
Expired
Application number
CA305,225A
Other languages
French (fr)
Inventor
Francis P. Giordano
Lawrence Kuhn
Ramon Lane
Chen-Hsiung Lee
Gene O. Zierdt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Business Machines Corp
Original Assignee
International Business Machines Corp
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 International Business Machines Corp filed Critical International Business Machines Corp
Application granted granted Critical
Publication of CA1098161A publication Critical patent/CA1098161A/en
Expired legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/005Typewriters 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
    • B41J2/01Ink jet
    • B41J2/015Ink jet characterised by the jet generation process
    • B41J2/02Ink jet characterised by the jet generation process generating a continuous ink jet
    • B41J2/025Ink jet characterised by the jet generation process generating a continuous ink jet by vibration

Landscapes

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

Abstract

INK JET PRINTING HEAD
Abstract of the Disclosure An ink jet printing head comprising a head body made from a material having high specific stiffness and the head body includes an ink passage which is kept small to retain the high body stiffness. The ink passage comprises a narrow slot connected with internal holes in the body which lead to ink inlet and exit ports. A nozzle plate having a plurality of orifices is fixed to the front of the head body and a piezoelectric crystal is fixed to the back of the head body. The piezoelectric crystal is kept thin compared to the head thickness, typically on the order of 1/20 to 1/30 of the body thickness, so that the effect of the crystal on the resonant characteristics of the assembly is kept small. The ink jet head provides a plurality of columns or jets of ink which are excited in such a way as to break up into uniformly and equally spaced drops at a fixed distance from the nozzle plate containing the orifices which produce the jets.

Description

17 Back~round of the Invention 18 One type of electrostatic pressure ink jet system is described in 19 Sweet et al, U.S. patent 3,373,437, wherein the pressuri~ed electrically conductive fluid is e~ected from a plurality of orifices and broken into 21 plural streams of uniform drops. As each drop breaks off from its fluid 22 filament, it may be selectively charged by an associated charge electrode.
23 This system operates binarily, giving a drop either a predetermined charge 24 or leaving it in an uncharged condition. The drops then pass through an electroseatic deflection field so that the charged drops are deflectet to 26 a drop catcher or gutter, while the uncharged drops are unde~lected and 27 continue past the deflection field to impact a recording ~edium for printing.
28 The charge on a drop is established in accordance with the fi~ld 29 produced by the charge electrode at the instant the drops break off from the filament. In the apparatus shown in U.S. Patent 3,739,393 to Lyons et al, "

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l a plurality of streams is generated by forcing the ink through a set of
2 orifices in an orifice plate and the streams are stimulated to produce
3 drops by vibrating the orifice plate at a point near one end and propagat-
4 ing a traveling wave along the plate to stimulate successive orifices wh:Lch causes some difference in breakoff distance in the streams and 6 also some phase difference, that is, a difference in time between suc-7 cessive stream breakoffs due to the traveling wave excitation. ~lore 8 uniform drop breakoff is achieved in the apparatus shown in U.S. Patent 9 3,882,508 by tapering the orifice plate along its length to compensate for the attenuation of the traveling wave along the orifice plate; however, ll this change does not correct the phase difference.
12 It is therefore the object of this invention to provide an ink jet 13 head of simplified design which produces a plurality of ink streams each 14 producing uniform drop breakoff and phasing.
Summary of the Invention 16 The ideal solution to achieve this objective is to design the ink 17 jet head so that the first natural resonance of the head is at a fre-18 quency greater than the operating frequency. However, using existing l9 engineering materials, it is not possible to design an ink jet head within the constraints of our desired dimensions and operating frequency 21 which can operate in this ideal mode.
22 Briefly according to the invention, the objective is achieved by 23 keeping the resonant frequency of the head as high as possible by using 2~ a high specific stiffness material and a design which retains the ad-vantages of this material so that a uniform mode shape is produced at 26 the operating frequency with nodal lines parallel to the ink jet array.
27 The ink jet head comprises a head body made from a material having 28 a high specific stiffness and the head body includes a slot communicating 29 with ink inlet and exit passages and extending to one face of the head body. A nozzle plate having a plurality of orifices is fixed to this face 1~)98~61 1 of the head body with the orifices in alignment with the ink slot so 2 that a plurality of ink streams is formed when pressurized ink is intro-3 duced into the ink inlet passage. An electromechanical transducer .
4 having a thickness small with respect to the thickness of the head body i~ fixed to the opposite face of the head body so that, when the transducer 6 i8 energized with a suitable high frequency slne wave, the ink streams 7 are broken up into uniform equally spaced drops at a fixed distance from 8 the nozzle plate.
9 Brief Description of the Drawings FIGURES la, lb, lc show respectively the front view, right side view 11 and a section view along lines A-A of the head body of the ink jet head 12 embodying our invention;
13 FIGURES 2a, 2b, 2c show respectively, front view, right side view and 14 bottom view of an ink jet head assembly utilizing the head body of Figure l;
FIGURES 3a, 3b and 3c show respectively, front view, right side view 16 and a section view along llne9 A-A of an alternate head body;
17 FIGURE 4 shows a perspective view of an ink jet head assembly utilizing 18 the head body of Figure 3;
19 FIGURE 5 is a graph which shows the percent reduction in the first resonant frequency of the head as a function of the thlckness ratio of the 21 transducer and head body.
22 Description of the Preferred Embodiments 23 The ink jet head according to the invention comprises a head body 10 24 having a nozzle plate 14 containing orifices 16 attached to ehe front of the body and an electromechanical transducer 18 attached to the back of the 26 body as shown in Figures 2 and 4. The purpose of the ink jet head is to 27 provide several columns or jets of fluid such as ink which is excited in 28 such a way as to break up into uniformly and equally spaced drops at a 29 fixed distance from the nozzle plate containing the orifices which produce the jets, ~L098~61 1 The basic head body as shown in Fig. ~ is a block of material with 2 an ink passage 12 formed in it. Any high specific stiffness material 3 which is chemically compatible with the ink and with other materials in 4 the head may be used. Stainless steel is one material that can be used and ceramic materials such as glass, alumina and silicon carbide may 6 also be used. The specific stiffness is defined by the relation p where 7 E is Young's Modules of Elasticity and p is the density of the material.
8 The specific stiffness for the materials listed above varies from 107X106 g inches for stainless steel to 600-800x106 inches for silicon carbide.
The ink passage 12 includes a small slot 28 extending to the face 36 of 11 the head body to which the nozzle plate 14 is fixed and ink inlet opening 12 30 and outlet opening 31 which extend through the end faces of the head 13 body to intersect with ink slot 28. The slot 28 is kept small to retain 14 the high body stiffness. By keeping the dimensions of the block small and compact, the resonant frequencies are kept high and resonances in 16 the frequency range of interest, typically 100 kilohertz to 200 kilohertz, 17 are minimized. Although the shape of the head body is shown as rectangular, 18 other shapes can be used as well, such as cylindrical with the faces either 19 parallel or perpendicular to the cylindrical axis.
The electromechanical transducer is attached to the back of the 21 head body and the thickness of the transducer is kept thin compared to 22 the head thickness. The preferred electromechanlcal transducer is a 23 piezoelectric crystal and a suitable transducer is the lead zirconate-lead 24 titanate ceramic sold under the tradename of PZT by Vernitron Piezoelectric Division, Bedford, Ohio. By utilizing a thin crystal, the effect of the 2~ crystal on the resonant characteristics of the assembly is kept small.
27 The stiffness and mass of the head body are so much greater than those 28 of the crystal that the resonant characteristics are essentially those 29 of the head body alone.

~:~31g8161 1 The ratio in percent of the first resonant frequency of the total 2 head f t and the first resonant frequency of the head body alone fOh is 3 plotted in Figure 5 versus the thickness ratio T for a steel head body 4 and a PZT4 crystal. Similar curves can be drawn for other material combina-tions. This figure illustrates the percent reduction in the first 6 resonant frequency of the head due to the presence of the crystal plate 7 versus the thickness ratio of the crystal and head body. In order to 8 keep the reduction within 10%, it can be seen from Figure 5 that the 9 thickness ratio should be less than 5%. Typical dimensions for an ink jet head are .5 inch fo~ the head body thickness T and .020 inch for the 11 crystal thickness t. This corresponds to a thickness ratio T of 4% and 12 this design produces less than a 10% reduction in the first resonant 13 frequency of the head.
14 As shown in Figure 2, the head body has a nozzle plate 14 bonded to ltS front surface 36 so that the orifices 16 are in alignment with the 16 narrow slots 28 in the head boty. The nozzle plate can be bonded to the 17 heat body by any suitable process which produces a uniform rigid bond 18 line and is chemically inert to the ink so that the nozzle plate is 19 forced to follow the vibratory motion of the head body as shown dotted in Figure 2C. Ink inlet port 32 is fitted within internal hole 30 and a 21 piezoelectric crystal 18 is bonded to the back surface 38 of the head 22 body. The crystal 18 can be bonded to the head body by any suitable 23 process which is capable of producing a rigid bond that is-thin with 24 respect to the crystal thickness to promote the maximum transfer of energy from the crystal to the head body. The preferred bonding material 26 is a suitable epoxy bonding material.
27 A sinusoidally varying voltage from source 20 is applied to the 28 crystal 18 to provide the excitation to the jets 22 so that the jets 29 break up at a fixed distance 24 from the nozzle plate into a series of uniformly and equally spaced drops 26. The drive from crystal 18 produces SA977009 ~5-l~g8~61 l a vibration at the face of the head body as shown dotted in Figure 2.
2 It is important to the production of drop breakoff at a fixed distance 3 24 from the nozzle that.the nodal points 34 of the vibration be parallel 4 to the row of orifices in nozzle plate 14. The ink jet head shape and dimensions are chosen to operate at a particular frequency at which the 6 head is driven so that the proper vibrational mode is produced as shown 7 in Figure 2.
8 When multiple columns of jets are desired, each is provided with a g separate slot 28 behind its orifices as shown in Figure 3. The head body 11 has two ink slots 28' and ink inlet opening 30' and exit opening 31' ]l which intersect with each ink slot 28'. The assembled head has a nozzle 12 plate lS having two rows of orifices 17. The nozzle plate is fixed to 13 head body 1~ so that the rows of orifices 17 are aligned with the ink 14 slots 28'. This structure maintains the high stiffness of the assembly and produces the nodal points 34' parallel to the rows of orifices as 16 shown in Figure 4 so that, when transducer 19 is excited by a suitable 17 sine wave voltage, uniform breakoff can also be obtained in each of the 18 multiple columns of jets provided in this head. This structure has the l9 advantage relative to other multi-column heads where a single cavity serves all of the columns. In these heads the nozzle plate covering 21 this large cavity becomes a relatively weak diaphragm, thereby introducing 22 complex resonant characteristics.
23 Several other advantages of this head are not related to its resonant 24 characteristics. One advantage is that the piezoelectric crystal is kept out of contact with the ink, thereby eliminating the need to pass crystal drive 26 current through the ink and preventing chemical attack of the crystal., crystal 27 electrodes or crystal bonding material by the ink. Another advantage is that 28 gaskets and "O" rings are not required to seal the ink passages and assembly 29 screws are eliminated. A third advantage is that the small ink passages permit high ink velocities through the passages when in a flow-through or flushing ~A977009 -6-~: 1a98~61 ,. . - :
.., ' , . . . .
1 mode, thereby facilitating removal of air bubbles or contaminants when they 2 affect operation, which is typically during the startup mode. An additional 3 advantage is that the small physical size and weight of the head makes it 4 desirable for incorporating it into a complete ink ~et print head assemblywhich includes the head described plus charge plates, deflection plates and 6 gutters.
` , 7 . While the invention has been particularly shown and described with ' 8 reference to a preferred embodiment thereof, it will be understood by 9 those skilled in the art that various changes in the form and details may be made ~herein without departing from the spirit and scope of the invention.

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Claims (10)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. A multi-nozzle ink jet head comprising:
a head body comprising a member having opposed faces separated by a predetermined distance, said head body having an ink inlet passage and at least one ink slot communicating with said inlet passage and extending to one of the faces of the head body;
a nozzle plate having a plurality of orifices therein;
said nozzle plate being fixed to said one face of said head body with its orifices in alignment with said ink slot so that a row of ink jet streams is formed when pressurized ink is introduced into said ink inlet passage;
an electromechanical transducer fixed to the opposed face of said head body from said one face; said electromechan-ical transducer having a thickness small with respect to said predetermined distance, and, means for vibrating said electro-mechanical transducer at a predetermined operating frequency to cause the ink jet streams to break up into uniform equally spaced drops at a fixed distance from the nozzle plate.
2. The invention according to Claim 1 wherein said electromechanical transducer thickness is less than about 1/20 said predetermined distance.
3. The invention according to Claim 1 wherein said head body has a plurality of ink slots and said nozzle plate has a plurality of rows of orifices with each row of orifices in alignment with one of said ink slots.
4. The apparatus of Claim 2 wherein said electromechan-ical transducer comprises a piezoelectric crystal.
5. The ink jet head of Claim 1 wherein said head, when energized, produces a vibrational mode at said one face having its nodal lines parallel to the row of ink jet streams.
6. A multi-nozzle ink jet head comprising:
a head body comprising a member made from a material having high specific stiffness and having opposed faces sep-arated by a predetermined distance, said head body having an ink inlet passage and at least one ink slot communicating with said inlet passage and extending to one of the faces of the head body;
a nozzle plate having a plurality of orifices therein;
said nozzle plate being fixed to said one face of said head body with its orifices in alignment with said ink slot so that a row of ink jet streams is formed when pressurized ink is introduced into said ink inlet passage;
an electromechanical transducer fixed to the opposed face of said head body from said one face; said electromechanical transducer having a thickness small with respect to said pre-determined distance and means for vibrating said electro-mechanical transducer at a predetermined operating frequency to cause the ink jet streams to break up into uniform equally spaced drops at a fixed distance from the nozzle plate.
7. The invention according to Claim 6 wherein said electromechanical transducer thickness is less than about 1/20 said predetermined distance.
8. The invention according to Claim 6 wherein said head body has a plurality of ink slots and said nozzle plate has a plurality of rows of orifices with each row of orifices in alignment with one of said ink slots.
9. The apparatus of Claim 7 wherein said electromechanical transducer comprises a piezoelectric crystal.
10. The ink jet head of Claim 1 wherein said head, when energized at said operating frequency, produces a vibrational mode at said one face having its nodal lines parallel to the row of ink jet streams.
CA305,225A 1977-10-03 1978-06-12 Ink jet printing head Expired CA1098161A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US05/839,093 US4188635A (en) 1977-10-03 1977-10-03 Ink jet printing head
US839,093 1977-10-03

Publications (1)

Publication Number Publication Date
CA1098161A true CA1098161A (en) 1981-03-24

Family

ID=25278839

Family Applications (1)

Application Number Title Priority Date Filing Date
CA305,225A Expired CA1098161A (en) 1977-10-03 1978-06-12 Ink jet printing head

Country Status (8)

Country Link
US (1) US4188635A (en)
JP (1) JPS5841745B2 (en)
BE (1) BE870089A (en)
CA (1) CA1098161A (en)
DE (1) DE2842755A1 (en)
FR (1) FR2404530B1 (en)
GB (1) GB1598602A (en)
IT (1) IT1159147B (en)

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES485764A1 (en) * 1978-11-15 1980-10-01 Thomae Gmbh Dr K Method and apparatus for dotting moulding devices by means of discrete droplets of a liquid or suspended lubricant during the manufacture of moulded objects in the pharmaceutical, food or catalytic field.
JPS5621863A (en) * 1979-07-31 1981-02-28 Ricoh Co Ltd Multinozzle head for ink jet
JPS56101869A (en) * 1980-01-21 1981-08-14 Ricoh Co Ltd Ink jet head
CA1156710A (en) * 1980-05-09 1983-11-08 Gary L. Fillmore Break-off uniformity maintenance
US4646104A (en) * 1982-06-21 1987-02-24 Eastman Kodak Company Fluid jet print head
US4554558A (en) * 1983-05-19 1985-11-19 The Mead Corporation Fluid jet print head
US4901093A (en) * 1985-11-26 1990-02-13 Dataproducts Corporation Method and apparatus for printing with ink jet chambers utilizing a plurality of orifices
EP0224937B1 (en) * 1985-12-06 1991-11-21 Hewlett-Packard Company Thermal ink jet print head assembly
US4683481A (en) * 1985-12-06 1987-07-28 Hewlett-Packard Company Thermal ink jet common-slotted ink feed printhead
US4680859A (en) * 1985-12-06 1987-07-21 Hewlett-Packard Company Thermal ink jet print head method of manufacture
US4683477A (en) * 1986-08-29 1987-07-28 Eastman Kodak Company Ink jet print head
DE3917434A1 (en) * 1989-05-29 1989-11-09 Siemens Ag Multi-layer ink printhead with ink channels which are produced by selective etching
DE69406734T2 (en) * 1993-08-17 1998-03-12 Scitex Digital Printing Inc Assembly arrangement for resonators
JP2957528B2 (en) * 1997-10-07 1999-10-04 株式会社東京機械製作所 Nozzle for inkjet printing, orifice member thereof, and method of manufacturing orifice member
EP1602484B1 (en) 1998-12-14 2011-09-21 Eastman Kodak Company Drop generator for long array ink jet printer
US6702196B2 (en) 1999-03-31 2004-03-09 Ngk Insulators, Ltd. Circuit for driving liquid drop spraying apparatus
WO2000060238A1 (en) * 1999-03-31 2000-10-12 Ngk Insulators, Ltd. Droplet spay device driving method and drive circuit
JP4636165B2 (en) * 2008-10-27 2011-02-23 富士ゼロックス株式会社 Droplet discharge apparatus and image forming apparatus

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3586907A (en) * 1969-11-17 1971-06-22 Mead Corp Laminated coating head
GB1464370A (en) * 1973-06-13 1977-02-09 Ici Ltd Pattern printing apparatus
SE349676B (en) * 1971-01-11 1972-10-02 N Stemme
US3787881A (en) * 1972-09-18 1974-01-22 Mead Corp Apparatus and method for bar code printing
US3823408A (en) * 1972-11-29 1974-07-09 Ibm High performance ink jet nozzle
DE2302849C3 (en) * 1973-01-20 1975-07-10 Olympia Werke Ag, 2940 Wilhelmshaven Nozzle printer, in particular for an inkjet writing mechanism
DE2313335C3 (en) * 1973-03-17 1975-08-21 Olympia Werke Ag, 2940 Wilhelmshaven Device for applying drops of liquid to a recording medium
GB1450340A (en) * 1973-08-16 1976-09-22 Matsushita Electric Ind Co Ld Arrangements for applying liquid droplets to a surface
US3900162A (en) * 1974-01-10 1975-08-19 Ibm Method and apparatus for generation of multiple uniform fluid filaments
US3927410A (en) * 1974-04-30 1975-12-16 Ibm Ink jet nozzle
US3871004A (en) * 1974-06-26 1975-03-11 Olympia Werke Ag Ink drop writing head
US3882508A (en) * 1974-07-22 1975-05-06 Mead Corp Stimulation apparatus for a jet drop recorder
JPS51117530A (en) * 1975-04-08 1976-10-15 Ricoh Co Ltd Ink drop jet device
US4065774A (en) * 1975-05-30 1977-12-27 International Business Machines Corporation Hybrid fluid jet drop generation
US4007465A (en) * 1975-11-17 1977-02-08 International Business Machines Corporation System for self-cleaning ink jet head

Also Published As

Publication number Publication date
BE870089A (en) 1978-12-18
GB1598602A (en) 1981-09-23
JPS5455436A (en) 1979-05-02
DE2842755A1 (en) 1979-04-12
FR2404530A1 (en) 1979-04-27
FR2404530B1 (en) 1985-10-04
IT7828243A0 (en) 1978-09-29
IT1159147B (en) 1987-02-25
US4188635A (en) 1980-02-12
JPS5841745B2 (en) 1983-09-14

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