Capping a printhead against a transfer roller

• US 6,334,664 B1
• Filed: 12/11/1999
• Issued: 01/01/2002
• Est. Priority Date: 12/16/1998
• Status: Expired due to Term

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Silverbrook, Kia
• Primary Examiner(s): Vo, Anh T. N.
• Application Number:
  US09/459,412
• Time in Patent Office: 752 Days
• Field of Search: 347/29-30, 347/103, 101/350.1, 101/350.5, 101/350.6, 101/351.1, 101/351.2, 101/351.4, 346/21, 346/32
• US Class Current: 347/32
• CPC Class Codes: B41J 11/0095 Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end
• CPC Class Codes: B41J 11/42 Controlling printing material conveyance for accurate alignment of the printing material with the printhead; Print registering
• CPC Class Codes: B41J 13/076 Construction of rollers; Bearings therefor
• CPC Class Codes: B41J 13/103 for the sheet feeding section
• CPC Class Codes: B41J 2/00 Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed mounting, arrangement or disposition of types or dies B41J1/00
• CPC Class Codes: B41J 2/155 for line printing
• CPC Class Codes: B41J 2/165 Preventing or detecting of nozzle clogging, e.g. cleaning, capping or moistening for nozzles
• CPC Class Codes: B41J 2/16508 connected with the printer frame
• CPC Class Codes: B41J 2/16588 Print heads movable towards the cleaning unit
• CPC Class Codes: B41J 29/023 with reduced dimensions
• CPC Class Codes: B41J 29/17 Cleaning arrangements
• CPC Class Codes: B41J 29/38 Drives, motors, controls or automatic cut-off devices for the entire printing mechanism
• CPC Class Codes: B41J 3/445 Printers integrated in other types of apparatus, e.g. printers integrated in cameras
• CPC Class Codes: B41J 3/60 for printing on both faces of the printing material
• CPC Class Codes: G06K 15/16 Means for paper feeding or form feeding

Abstract

A print engine for a printer includes a page width printhead. The printhead includes an ink-ejecting device and a seal surrounding the ink-ejecting device. A transfer roller is arranged adjacent the printhead. Ink ejected by the printhead is received on the transfer roller to be transferred to a sheet of paper. A displacement unit displaces the printhead so that its seal is urged into abutment of the surface of the transfer roller when the printhead is inoperative to inhibit evaporation of ink from the ink-ejecting device. The displacement unit is further operable to draw the printhead into spaced relationship relative to the transfer roller when printing is to be effected.

Claims

1. A print engine for a printer, the print engine including:

a page width printhead, the printhead including an ink-ejecting means comprising a semi-conductor device defining an array of inkjet nozzles which provides photographic-quality and magazine-quality printing and a sealing means surrounding the ink-ejecting means;

a smooth-surfaced transfer means having a discontinuity-free peripheral wall onto which ink ejected by the printhead is received to be transferred to a sheet of print media, the transfer means being arranged adjacent to the printhead; and

a displacement means for displacing the printhead so that its sealing means is urged into abutment with a surface of the transfer means when the printhead is inoperative to inhibit evaporation of ink from the ink-ejecting means, the displacement means further being operable to draw the printhead into spaced relationship relative to the transfer means when printing is to be effected.

2. The print engine as claimed in claim 1 in which the ink-ejecting means of the printhead is a microelectromechanical device having a plurality of inkjet nozzles.

3. The print engine as claimed in claim 1 in which the sealing means is an elastomeric seal surrounding the ink-ejecting means.

4. The print engine as claimed in claim 1 in which the transfer means includes a transfer roller rotatably mounted adjacent to the printhead so that ink ejected by the printhead is deposited on a surface of the transfer roller.

5. The print engine as claimed in claim 1 in which the displacement means includes an electromagnetically operable device.

6. The print engine as claimed in claim 5 in which the electromagnetically operable device is a solenoid which, to draw the printhead away from the transfer means, requires a first, higher current and to hold the printhead in spaced relationship relative to the transfer means requires a second, lower current.

7. The print engine as claimed in claim 1 which includes an urging means for urging a sheet of print media into contact with the surface of the transfer means.

8. The print engine as claimed in claim 7 in which the urging means is a pinch roller.

9. The print engine as claimed in claim 7 in which the urging means is a transfer means of an opposed, aligned print engine.

10. The print engine as claimed in claim 7 which includes a cleaning station for cleaning the surface of the transfer means, the cleaning station being arranged intermediate the urging means and the printhead.

11. The print engine as claimed in claim 10 in which the cleaning station includes a cleaning element of an absorbent, resiliently flexible material and a wiper of a resiliently flexible material, the wiper being arranged intermediate the cleaning element and the printhead.