(19)
(11) EP 0 749 834 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
23.07.1997 Bulletin 1997/30

(43) Date of publication A2:
27.12.1996 Bulletin 1996/52

(21) Application number: 96109564.3

(22) Date of filing: 14.06.1996
(51) International Patent Classification (IPC)6: B41J 2/05
(84) Designated Contracting States:
DE FR GB

(30) Priority: 22.06.1995 IT TO950521

(71) Applicant: OLIVETTI-CANON INDUSTRIALE S.p.A.
10015 Ivrea (TO) (IT)

(72) Inventors:
  • Scardovi, Alessandro
    10015 Ivrea (TO) (IT)
  • Sandri, Tazio
    10015 Ivrea (TO) (IT)

(74) Representative: Casuccio, Carlo et al
Olivetti S.p.A. Via G. Jervis 77
10015 Ivrea (Torino)
10015 Ivrea (Torino) (IT)

   


(54) Ink-jet print head with integrated driving components


(57) In an ink jet printhead (100) comprising ejection resistors (Ri) and MOS transistors (TRi) for supplying the resistors the energy for ejecting droplets of ink, integrated on the same semiconductor substrate, a given range of values is defined for the ratio of the channel resistance (Rc) during conduction of the MOS transistor to the resistance (R) of the ejection resistor so that the energetic operating point (El) of the ejection resistor is automatically compensated for variations in temperature (Ts) of the substrate, thereby assuring quality of printing and preventing ejection resistor conditions of operation liable to damage the resistor itself.






Search report