Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
104 words
An ink jet printing head comprising at least one tubular printing element having a capillary nozzle at one end and communicating at the other end directly with a reservoir for the ink, the printing element being associated with a piezoelectric transducer for varying the volume of the printing element, the printing element and transducer being disposed in a single block, characterised in that the reservoir is closed at the top by a first arched wall at the level of the said other end of the printing element, so as to facilitate expulsion by way of the nozzle of any bubbles present in the reservoir.
Claim 2
Dependent Claim
104 words
An ink jet printing head comprising at least one tubular printing element having a capillary nozzle at one end and communicating at the other end directly with a reservoir for the ink, the printing element being associated with a piezoelectric transducer for varying the volume of the printing element, the printing element and transducer being disposed in a single block, characterised in that the reservoir is closed at the top by a first arched wall at the level of the said other end of the printing element, so as to facilitate expulsion by way of the nozzle of any bubbles present in the reservoir.
Claim 3
Dependent Claim
41 words
A printing head according to claim 1, wherein the reservoir comprises a second wall of porous material through which the ink passes by capillary action, the porous wall hydraulically separating the reservoir from a source for the supply of the ink.
Claim 4
Dependent Claim
17 words
A printing head according to claim 2, wherein the second wall is opposite the first arched wall.
Claim 5
Dependent Claim
29 words
A printing head according to claim 2, wherein the second wall is adjacent to the first arched wall and opposite to the said second end of the printing element.
Claim 6
Dependent Claim
45 words
A printing head according to claim 1, wherein the reservoir comprises a tubular conduit communicating at a first end with the printing element and having a second end a porous filter element hydraulically separating the tubular conduit from a source for supply of the ink.
Claim 7
Dependent Claim
33 words
A printing head according to claim 5, wherein the tubular conduit is of synthetic rubber which is impermeable with respect to gases and vapours, with a hardness of between 30 and 75 Shore-A.
Claim 8
Dependent Claim
36 words
A printing head according to claim 5, wherein the tubular conduit is of synthetic rubber which is permeable with respect to gases and vapours and is arranged in an ink-filled container fixed to the printing head.
Claim 9
Dependent Claim
69 words
A printing head according to claim 1, comprising a plurality of tubular printing elements wherein the reservoir comprises a plurality of divider baffles and a filter element of porous material co-operating with the baffles to divide the reservoir into a plurality of cells, each cell corresponding to a printing element, whereby a cell is hydraulically separated from the others and from a common source for the supply of ink.
Claim 10
Dependent Claim
20 words
A printing head according to claim 8, wherein each cell has a volume between 15 and 3 mm 3 .
Claim 11
Dependent Claim
39 words
A printing head according to claim 8 or 9, wherein the cells are defined by walls of elastic material which is impermeable with respect to the ink and which is of a hardness of between 25 and 40 Shore-A.