Method and apparatus for replenishing an ink-jet head with ink

Claim 2

Apparatus for replenishing an ink-jet print head with ink according to claim 1, characterised in that the connection element (2) comprises a plurality of capillary ducts parallel to a longitudinal axis of the element each duct having an average diameter of between 50 and 500 µm.

Claim 3

Apparatus for replenishing an ink-jet print head with ink according to claim 1 or 2, characterised in that the connection element consists of expanded polymer material.

Claim 4

Apparatus for replenishing an ink-jet print head with ink according to claim 3, characterised in that the polymer material is a polyether urethane resin.

Claim 5

Apparatus for replenishing an ink-jet print head with ink according to claim 3, characterised in that the polymer material is a melamine resin.

Claim 6

Apparatus for replenishing an ink-jet print head with ink according to claim 3, characterised in that the polymer material is based on a polyvinyl alcohol.

Claim 7

Apparatus for replenishing an ink-jet print head with ink according to claim 1 or 2, characterised in that the connection element consists of a fibrous material.

Claim 8

Apparatus for replenishing an ink-jet print head with ink according to claim 7, characterised in that the fibrous material comprises fibre of a polyurethane-coated polyester.

Claim 9

Apparatus for replenishing an ink-jet print head with ink according to claim 7, characterised in that the fibrous material comprises polyamide fibres.

Claim 10

Apparatus for replenishing an ink-jet print head with ink according to claim 1 or 2, characterised in that the connection element is composed of an open-cell porous ceramic material.

Claim 11

Apparatus for replenishing an ink-jet print head with ink according to claim 2 to 11, characterised in that the connection element has a substantially cylindrical shape, having a transverse dimension of at least one order of magnitude greater than the diameter of each of the capillary ducts.

Claim 12

Apparatus for replenishing an ink-jet print head with ink according to any one of the preceding claims, characterised in that the supply reservoir (10) includes an annular compression element (14) fixed in the opening (12) and projecting inside the reservoir so as to compress the spongy body (1) locally, the compression element comprising a through-hole for exposing the portion of the spongy body and for receiving the connection element (2).

Claim 13

Apparatus for replenishing an ink-jet print head with ink according to any one of claims 1 to 12, characterised in that the connection element (20) has a rigidity greater than the rigidity of the first spongy body and in that the connection element is introduced partially into the opening (12) so as to compress locally the spongy body (1), so that hyraulic continuity is rapidly achieved between the main container and the spongy body.

Claim 14

Apparatus for replenishing an ink-jet print head with ink according to any one of claims 1 to 12, characterised in that the supply reservoir (10) includes a separator element (20) located between the spongy body (1) and the opening (12), the separator element being composed of a rigid porous material having a capillarity greater than the capillarity of the spongy body, so that when the connection element is brought up to the separator element, hydraulic continuity between said main container and the supply reservoir is achieved in a rapid and reliable manner.

Claim 15

Apparatus for replenishing an ink-jet print head with ink according to any preceding claim, characterised in that the main container (4) contains ink up to a level such as to create, with respect to the print head, a pressure head (H) with an absolute value less than the characteristic negative pressure of the spongy body.

Claim 16

Apparatus for replenishing an ink-jet print head with ink according to one of claims 1 to 12, characterised in that the head is mounted on a support structure (44) comprising a chamber (45) for supplying the head, kept full of ink, and in that the ink reservoir (55) can be removably inserted into the support so as to allow replacement thereof when the ink is used up, connecting means (58) being provided on the support for transferring the ink from the reservoir to said head.

Claim 17

Apparatus for replenishing an ink-jet print head with ink according to claim 16, characterised in that the connecting means (58) comprise a porous element with one end immersed in the supply chamber (45) and with another end projecting with respect to the support, the reservoir having an opening in the region of the porous element for bringing the spongy body into contact with the porous element when the reservoir (55) is inserted into the support.

Claim 18

Ink-jet printer comprising a print head (61) movable between two end positions and connected to a supply reservoir (10) containing a spongy body (1) adapted to be soaked with ink for supplying the head, a main ink container (74, 90)) arranged adjacent to one of the end positions and means (70, 87) for connecting hydraulically said container to the supply reservoir, characterised in that the connecting means comprise a connecting element (70, 87) made of porous material partially immersed in the container (74, 90) and designed to be brought up to the spongy body (1) through an opening (82) in the reservoir (10) for exposing a zone of the spongy body, when the head is located in said one end position in order to establish hydraulic continuity between the main container and the supply reservoir, so that the spongy body is replenished with ink sucked from the container as a result of capillarity.

Claim 19

Printer according to claim 18, characterised in that the opening (82) is formed through a bottom wall of the supply reservoir and that the main container (74, 90) is movable vertically from a rest position to a replenishing position occupied when thehead is located in one end position in order to bring the connecting element (87) up to the spongy body via the opening.

Claim 20

Printer according to claim 19,, characterised in that the main container is moved by a lever (94) actuated by the head when it reaches the end position.

Claim 21

Method for replenishing with ink an ink-jet print head comprising a supply reservoir connected to the head and containing a spongy body (1) adapted to be soaked with ink, the method comprising the following steps: a) providing the reservoir with an opening (12) communicating with the exterior so as to expose a zone (3) of the spongy body; b) arranging a container (4) full of ink in the vicinity of the supply reservoir with the free surface of the ink forming a hydraulic head (11), with respect to said print head, having an absolute value less than the characteristic negative pressure exerted by the spongy body; c) arranging a porous element (2) with capillary ducts so as to be partially immersed in the container; d) bringing a non-immersed part of the porous element (2) projecting from the container up to the zone (3) via the opening (12) in order to establish hydraulic continuity between the porous element and the spoongy body (1), so that the supply reservoir is replenished with ink sucked from the container (4) as a result of capillarity.