초록 ▼

An ink jet print head (10) has a supply channel (14, 24, 52) connecting an ink source with an upper manifold (60U) and a lower manifold (60L). Each manifold has a tapered structure. From each manifold multiple inlet channels (36, 34, 44, 54) each lead to a respective pressure chamber (28) from which

An ink jet print head (10) has a supply channel (14, 24, 52) connecting an ink source with an upper manifold (60U) and a lower manifold (60L). Each manifold has a tapered structure. From each manifold multiple inlet channels (36, 34, 44, 54) each lead to a respective pressure chamber (28) from which an outlet channel (40, 38, 46, 56, 62, 76, 82) leads to nozzles (88) from which droplets of liquid ink are expelled as a result of the action of a pressure transducer on the pressure chamber. Each manifold is separated from the supply channel by a baffle structure (92) that includes three baffles (94) formed by alternating plates (64, 78) having an open manifold with plates (58, 72) having a blocked manifold. The baffle structure reduces jetting nonuniformity by damping pressure displacement waves in the ink caused by the expulsion of ink droplets. The baffle structure also promotes effective heat transfer from the print head to ink being drawn in to the print head from the ink source. The print head is operated by drawing ink from the supply channel through the baffle structure to replace ink drawn from the manifold as a result of expulsion of ink from the nozzles.

대표청구항 ▼

[ We claim:] [1.] An ink jet print head having multiple printing nozzles in fluid connection with a supply channel for transporting liquid ink to the print head, comprising:at least one group of inlet channels connected to the supply channel;at least one group of pressure chambers, each in fluid con

[ We claim:] [1.] An ink jet print head having multiple printing nozzles in fluid connection with a supply channel for transporting liquid ink to the print head, comprising:at least one group of inlet channels connected to the supply channel;at least one group of pressure chambers, each in fluid connection with a respective one of the inlet channels and operable by action of transducers to cause discharge of liquid ink through one of the nozzles and by the action of transducers to cause the liquid ink to refill the pressure chambers;at least one manifold in fluid connection between the supply channel and the group of inlet channels, the group of inlet channels opening on the manifold; andat least one damping structure located between the supply channel and the manifold and defining plural fluid passageways between the supply channel and the manifold, the fluid passageways having a fluid aspect ratio w/h.sub.i greater than about 5 so that h.sub.i is sufficiently small such that bubbles entrained in the ink passing through the passageways between the supply channel and the manifold are reduced in size to thereby readily diffuse into the ink to improve purging performance of the print head wherein the damping structure comprises a baffle structure and w represents a width of the baffle structure transverse to a direction of flow of the liquid ink and h.sub.i represents a height of a baffle flow passage.