US 12,233,646 B2
Continuous ink jet printer and print head assembly therefor
Stephen John Cooke, St. Ives (GB)
Assigned to Linx Printing Technologies Limited, St Ives (GB)
Appl. No. 17/629,504
Filed by Linx Printing Technologies Limited, St. Ives (GB)
PCT Filed Jul. 22, 2020, PCT No. PCT/GB2020/051745
§ 371(c)(1), (2) Date Jan. 24, 2022,
PCT Pub. No. WO2021/014148, PCT Pub. Date Jan. 28, 2021.
Claims priority of application No. 1910570 (GB), filed on Jul. 24, 2019.
Prior Publication US 2022/0242117 A1, Aug. 4, 2022
Int. Cl. B41J 2/085 (2006.01); B41J 2/02 (2006.01); B41J 2/08 (2006.01); B41J 2/095 (2006.01); B41J 2/14 (2006.01); B41J 2/41 (2006.01); B41J 29/38 (2006.01)
CPC B41J 2/085 (2013.01) [B41J 2/02 (2013.01); B41J 2/08 (2013.01); B41J 2/095 (2013.01); B41J 2/14072 (2013.01); B41J 2/41 (2013.01); B41J 29/38 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An electrostatic deflection continuous ink jet printer comprising:
a printer body, a print head and a flexible conduit extending between the printer body and the print head,
the print head comprising (a) an ink gun for forming a continuous ink jet, (b) an arrangement of electrodes to trap electric charges on ink drops of the ink jet and to create an electrostatic field to deflect ink drops carrying trapped electric charges, (c) a gutter for receiving ink drops of the ink jet that are not used for printing and (d) a print head cover that extends over at least a part of a volume in which the ink drops travel in operation of the printer, the print head cover having an exit hole to enable ink drops that are used for printing to exit the said volume, wherein the print head cover is made entirely or mostly from a mouldable polymeric material,
the printer comprising (e) a cover earth line extending from the print head cover,
at least a part of the print head cover having an electrical surface resistivity of no more than 1012 ohms per square or an electrical volume resistivity of no more than 109 ohm.metres, the said at least a part of the print head cover surrounding the exit hole and being electrically connected to the cover earth line.
 
13. A print head assembly for an electrostatic deflection continuous ink jet printer, the print head assembly comprising:
a print head and a flexible conduit attached to and extending away from the print head,
the print head comprising (a) an ink gun for forming a continuous ink jet, (b) an arrangement of electrodes to trap electric charges on ink drops of the ink jet and to create an electrostatic field to deflect ink drops carrying trapped electric charges, (c) a gutter for receiving ink drops of the ink jet that are not used for printing and (d) a print head cover that extends over at least a part of a volume in which the ink drops travel in operation of the printer, the print head cover having an exit hole to enable ink drops that are used for printing to exit the said volume, wherein the print head cover is made entirely or mostly from a mouldable polymeric material,
the print head assembly comprising (e) a cover earth line extending from the print head cover,
at least a part of the print head cover having an electrical surface resistivity of no more than 1012 ohms per square or an electrical volume resistivity of no more than 109 ohm.metres, the said at least a part of the print head cover surrounding the exit hole and being electrically connected to the cover earth line.