Patent EA-004492-B1 (EA)
Title: Liquid dispensing apparatus
IPC: B41J/
Filed: 1999-03-02
Abstract: 1. Device for dispensing liquids, comprising a liquid tank (5), a dispensing nozzle (7), and an elongated tubular liquid conduit (3) with an end connected to the liquid tank (5) for supplying liquid (6) from the liquid tank (5) to the dispensing nozzle (7), and vibrator means for inducing a vibrating action of the dispensing nozzle across the liquid conduit (3), characterized in that vibrator means is connected with the liquid conduit (3) through a resonator (2), made in form of flat metallic plate, wherein the vibrator means is made with the possibility of exciting the transversal vibrations resulting in an acceleration of the nozzle (7) sufficient to cause detachment of the liquid from the nozzle (7) in direction, substantially normal to the conduit (3). 2. The device according to claim 1, characterized by that the liquid conduit (3) is integral with the dispensing nozzle (7). 3. The device according to claim 2, characterized by that a free end of the liquid conduit (3) is cut at an angle, and the cut free end functions as the dispensing nozzle (7). 4. The device according to any one of the claims 1 to 3, characterized by that the vibrator means comprises a piezo-electric transducer (4). 5. The device according to any one of the claims 1 to 4, characterized by that the liquid conduit (3) is a hollow metal tube. 6. The device according to any one of the claims 3 to 5, characterized by that the transducer (4) is attached to the liquid conduit (3) through a resonator (2). 7. The device according to any one of the claims 3 to 6, characterized by that the transducer (4), the resonator (2) and the conduit (3) constitute a resonating unit. 8. The device according to the claims 1-7, characterized by that the resonator (2) is drop-shaped with a circular part (2a) having a triangular extension (2b) integral with the circular part (2a). 9. The device according to any one of the claims 6 to 8, characterized by comprising means for varying the hydrostatic pressure of the liquid (6) in the liquid tank (5) and/or in the liquid conduit (3). 10. The device according to any one of the claims 3 to 9, characterized by that the transducer (4) is a circular disk-shaped piezoelectric transducer, and the steel plate is substantially drop-shaped with a circular part having a triangular extension integral with the circular part, the transducer (4) being attached to parallel to the circular part in a concentric position and the apex of the triangular extension being attached to the liquid conduit (3). 11. The device according to any one of the claims 3 to 10, characterized by further comprising externally controlled driver means for driving the transducer (4) at predetermined variable frequencies. 12. A printing head comprising multiple liquid dispensing means for dispensing dye in controlled amounts in predetermined, controlled locations of a printing medium, wherein the liquid dispensing means comprises liquid dispensing device according to claims 1 to11. 13. The printing head according to claim 12, characterized by comprising parallel slots (20) for receiving the liquid dispensing devices (1). 14. The printing head according to claim 13, characterized by further comprising contact springs (19) for fastening the liquid dispensing devices (1) to the wall of the slots (20). 15. The printing head according to any one of the claims 12 to 14, characterized by comprising multiple dispensing devices (1) arranged in a line (L), and further comprising moving means for translating movement of at least the nozzles (7) of the dispensing devices in a direction parallel to the line (L). 16. The printing head according to any one of the claims 12 to 15, characterized by comprising adjustment means for an additional translating movement of the nozzles (7) of the dispensing devices (1) in a direction perpendicular to the line (L), simultaneously or individually for each nozzle (7). 17. Printing system with a printing medium (M) feeding mechanism (G, EM, D, R) and at least one printing head (10) for dispensing dye in controlled amounts in predetermined, controlled locations of the printing medium (M), characterized by comprising a printing head (10) according to any one of the claims 12 to 16. 18. The printing system according to claim 17, characterized by comprising multiple printing heads, with each printing head dedicated to a predetermined colour. 19. Device for dispensing liquids, comprising a dispensing nozzle (7), and an elongated tubular liquid conduit (3) connected to the dispensing nozzle (7) and vibrator means for inducing a vibrating action of the dispensing nozzle across the liquid conduit (3), characterized in that the vibrator means is connected with the liquid conduit (3) through a resonator (2), made in form of flat metallic plate, wherein the vibrator means is made with the possibility of exciting the transversal vibrations resulting in an acceleration of the nozzle (7) sufficient to cause detachment of the liquid from the nozzle (7) in direction, substantially normal to the conduit (3). 20. Device according to claim 19, characterized by further comprising means for connection to a liquid tank (5). 21. Device according to claim 19 or 20, characterized by further comprising a protective casing (21) with an opening (23) to allow the dispensing of the liquid. 22. Device according to any of claim 19 to 21, characterized in that the vibrator means comprises a piezo-electric transducer (4). 23. The device according to any one of the claims 19 to 22, characterized by that the transducer (4), resonator (2), and liquid conduit (3) forms resonating module. 24. The device according to any of claims 19-23, characterized by that the resonator (2) is drop-shaped with a circular part (2a) having a triangular extension (2b) integral with the circular part (2a).