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US4417255A Expired / Lapsed US ⏱️ 0.0 years remaining

Ink-jet printer

Assignee: Ricoh Co Ltd
•
Filing: 1981-08-19
•
Granted: 1983-11-22
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Expires: 2001-08-19
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Abstract

Abstract An ink-jet printer for forming desired characters on a recording medium by ink droplets is provided. In accordance with the present ink-jet printer, the third harmonic vibration as well as the fundamental harmonic vibration is imparted to the ink inside the ink nozzle so that ink droplets regularly spaced from each other without ink satellites therebetween may be produced. One embodiment of the present invention proposes to provide a vibrator having a resonant frequency three times higher than the exciting frequency. Another embodiment of the present invention proposes to mount the vibrator on the nozzle at a specific location with respect to the mouth of the nozzle.

Inventors

  • 👤 Isokazu Furukawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 03:10
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/015; B41J2/02; B41J2/025

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 74 words
An ink-jet printer for forming characters on a recording medium by ink droplets in a dot-matrix format comprising: an ink nozzle; ink supply means for supplying ink to said nozzle; vibrating means mounted on said nozzle for imparting vibration to the ink contained in said nozzle, said vibrating means having the resonant frequency of 3f o ; and driving means for driving said vibrating means with a driving signal having frequency f o .
Claim 2
Dependent Claim 74 words
An ink-jet printer for forming characters on a recording medium by ink droplets in a dot-matrix format comprising: an ink nozzle; ink supply means for supplying ink to said nozzle; vibrating means mounted on said nozzle for imparting vibration to the ink contained in said nozzle, said vibrating means having the resonant frequency of 3f o ; and driving means for driving said vibrating means with a driving signal having frequency f o .
Claim 3
Dependent Claim 39 words
The ink-jet printer of claim 1 wherein the thickness of said vibrating means in the lengthwise direction of said nozzle is set to the value obtained by dividing the frequency constant of said vibrating means by 3f o .
Claim 4
Dependent Claim 43 words
The ink-jet printer of claim 1 wherein the thickness of said vibrating means in the radial direction of the lengthwise direction of said nozzle is set to the value obtained by dividing the frequency constant of said vibrating means by 3f o .
Claim 5
Dependent Claim 14 words
The ink-jet printer of claim 1 wherein said vibrating means comprises an electrostrictive vibrator.
Claim 6
Dependent Claim 14 words
The ink-jet printer of claim 1 wherein said vibrating means comprises a magnetostrictive vibrator.
Claim 7
Dependent Claim 14 words
The ink-jet printer of claim 1 wherein said vibrating means comprises a piezoelectric vibrator.
Claim 8
Dependent Claim 114 words
An ink-jet printer for forming characters on a recording medium by ink droplets in a dot-matrix format comprising: an ink nozzle; ink supply means for supplying ink to said nozzle; vibrating means mounted on said nozzle for imparting vibration to the ink contained in said nozzle; and driving means for driving said vibrating means with a driving signal having frequency f o , whereby said vibrating means is mounted on said nozzle such that the distance between the mouth of said nozzle and the front end surface of said vibrating means satisfies the condition of (λ/12)(n+1) where λ is the wavelength corresponding to the frequency f o and n is a positive integer number.
Claim 9
Dependent Claim 114 words
An ink-jet printer for forming characters on a recording medium by ink droplets in a dot-matrix format comprising: an ink nozzle; ink supply means for supplying ink to said nozzle; vibrating means mounted on said nozzle for imparting vibration to the ink contained in said nozzle; and driving means for driving said vibrating means with a driving signal having frequency f o , whereby said vibrating means is mounted on said nozzle such that the distance between the mouth of said nozzle and the front end surface of said vibrating means satisfies the condition of (λ/12)(n+1) where λ is the wavelength corresponding to the frequency f o and n is a positive integer number.
Claim 10
Dependent Claim 40 words
The ink-jet printer of claim 7 further comprising additional vibrating means mounted on said nozzle such that the distance between the mouth of said nozzle and the frond end surface of said additional vibrating means satisfies the condition of (λ/4)(n+1).
Claim 11
Dependent Claim 19 words
The ink-jet printer of claim 8 wherein said driving means is commonly used to drive said two vibrating means.

References Cited (Backward Citations)

US3281859A Cited
US3683396A Cited
US3972474A Cited
US4350986A Cited
US4107698A Cited
US4336544A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-11-21 1987-05-23 1987-11-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-11-21 1991-05-23 1991-11-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-11-21 1995-05-23 1995-11-22 $7700.00 Window Closed / Lapsed

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