Reliable contact pad arrangement on plastic print cartridge

• US 6,174,046 B1
• Filed: 01/06/1998
• Issued: 01/16/2001
• Est. Priority Date: 10/06/1994
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Wilson, Arthur K., Harris, Donald G., Hamlin, Mindy A., Reid, W. Bruce, Azmoon, Majid
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): JACKSON, JUANITA DIONNE
• Application Number:
  US09/003,411
• Time in Patent Office: 1,106 Days
• Field of Search: 347/20, 347/50, 347/84, 347/85, 347/86, 347/87, 347/37
• US Class Current: 347/50
• CPC Class Codes: B41J 2/14072 Electrical connections, e.g. details on electrodes, connecting the chip to the outside...
• CPC Class Codes: B41J 2/1433 Structure of nozzle plates
• CPC Class Codes: B41J 2/1603 of the front shooter type
• CPC Class Codes: B41J 2/1623 bonding and adhesion
• CPC Class Codes: B41J 2/1626 etching
• CPC Class Codes: B41J 2/1631 photolithography
• CPC Class Codes: B41J 2/1632 machining
• CPC Class Codes: B41J 2/1634 laser machining
• CPC Class Codes: B41J 2/1643 thin film formation by plating
• CPC Class Codes: B41J 2/1752 Mounting within the printer
• CPC Class Codes: B41J 2/1753 Details of contacts on the cartridge, e.g. protection of contacts
• CPC Class Codes: B41J 2/17559 Cartridge manufacturing
• CPC Class Codes: B41J 25/34 Bodily-changeable print heads or carriages
• CPC Class Codes: H05K 1/118 specially for flexible printed circuits, e.g. using folded portions

Abstract

The contact pads of a print cartridge are formed on a flexible tape. Each of the uniformly spaced contact pads is preferably a square separated from an adjacent square by a minimum distance to provide each contact pad with a maximum area. Conductive traces run along the flexible tape and between the contact pads to allow for a minimum separation between contact pads, thus allowing the contact pads to be made relatively large. This improves the reliability of the interconnection between the pads and the printer electrodes.

Claims

1. A print cartridge comprising:

a print cartridge body having a first side; and

a flexible circuit secured on at least said first side of said print cartridge body, said flexible circuit comprising;

an insulating flexible tape having a length and a width;

a first set of contact pads formed on said flexible tape for contacting corresponding electrodes in an ink printer, said first set of contact pads being arranged in rows and columns along a first edge portion of said flexible tape and having a first width;

a second set of contact pads formed on said flexible tape for contacting corresponding electrodes in an ink printer, said second set of contact pads being arranged in rows and columns along a second edge portion of said flexible tape and having a second width;

conductive traces formed on said flexible tape, said traces running between a printhead electrode contact area and said contact pads, said traces running in a lengthwise direction from said printhead electrode contact area along a middle portion of said flexible tape such that there are no traces running between columns of said first set of contact pads and between columns of said second set of contact pads; and

a region on said flexible tape between said first set of contact pads and said second set of contact pads that does not contain any contact pads, said region having a width at least as wide as said first width and at least as wide as said second width, and a length at least as long as said columns in said first and second sets of contact pads.

2. The cartridge of claim 1 wherein said traces run between rows of contact pads in a direction perpendicular to a lengthwise centerline of said flexible tape when contacting contact pads along outer edges of said flexible tape to minimize a gap between said contact pads in adjacent columns and adjacent rows of said contact pads.

3. The cartridge of claim 2 wherein said contact pads in a row along said outer edges of said flexible tape are staggered to provide space between contact pads in adjacent rows for said traces to run to contact said contact pads.

4. A printing system comprising:

a scanning carriage for scanning across a print zone in an inkjet printer, said scanning carriage having at least one receptacle for receiving a print cartridge, said scanning carriage including electrodes for contacting contact pads on a print cartridge;

a print cartridge installed in said at least one receptacle, said print cartridge comprising;

a print cartridge body having a first side; and

a flexible circuit secured on at least said first side of said print cartridge body, said flexible circuit comprising;

an insulating flexible tape having a length and a width;

a first set of contact pads formed on said flexible tape for contacting corresponding electrodes in an ink printer, said first set of contact pads being arranged in rows and columns along a first edge portion of said flexible tape and having a first width;

a second set of contact pads formed on said flexible tape for contacting corresponding electrodes in an ink printer, said second set of contact pads being arranged in rows and columns along a second edge portion of said flexible tape and having a second width;

conductive traces formed on said flexible tape, said traces running between a printhead electrode contact area and said contact pads, said traces running in a lengthwise direction from said printhead electrode contact area along a middle portion of said flexible tape such that there are no traces running between columns of said first set of contact pads and between columns of said second set of contact pads; and

a region on said flexible tape between said first set of contact pads and said second set of contact pads that does not contain any contact pads, said region having a width at least as wide as said first width and at least as wide as said second width, and a length at least as long as said columns in said first and second sets of contact pads.

5. The system of claim 4 wherein said traces run between rows of contact pads in a direction perpendicular to a lengthwise centerline of said flexible tape when contacting contact pads along outer edges of said flexible tape to minimize a gap between said contact pads in adjacent columns and adjacent rows of said contact pads.

6. The system of claim 5 wherein said contact pads in a row along said outer edges of said flexible tape are staggered to provide space between contact pads in adjacent rows for said traces to run to contact said contact pads.

7. The system of claim 4 wherein said at least one receptacle comprises a plurality of receptacles, and wherein said print cartridge is a first print cartridge, installed in one of said receptacles, printing at an ink drop resolution of 300 dots per inch, said system also comprising:

a second print cartridge, installed in another of said receptacles, printing at an ink drop resolution of 600 dots per inch, said second print cartridge comprising;

a second print cartridge body having a first side;

a flexible circuit secured on at least said first side of said second print cartridge body, said flexible circuit comprising;

an insulating flexible tape having a length and a width;

a first set of contact pads formed on said flexible tape for contacting corresponding electrodes in an ink printer, said first set of contact pads being arranged in rows and columns along a first edge portion of said flexible tape and having a first width;

a second set of contact pads formed on said flexible tape for contacting corresponding electrodes in an ink printer, said second set of contact pads being arranged in rows and columns along a second edge portion of said flexible tape and having a second width;

conductive traces formed on said flexible tape, said traces running between a printhead electrode contact area and said contact pads, said traces running in a lengthwise direction from said printhead electrode contact area along a middle portion of said flexible tape such that there are no traces running between columns of said first set of contact pads and between columns of said second set of contact pads; and

a region on said flexible tape between said first set of contact pads and said second set of contact pads that does not contain any contact pads, said region having a width at least as wide as said first width and at least as wide as said second width, and a length at least as long as said columns in said first and second sets of contact pads.

8. A printing system comprising:

a scanning carriage for scanning across a print zone in an inkjet printer, said scanning carriage having at least one receptacle for receiving a print cartridge, said scanning carriage including electrodes for contacting contact pads on a print cartridge; and

a print cartridge installed in said at least one receptacle, said print cartridge comprising;

a print cartridge body including a first side having a depressed valley along a middle portion of said first side running along a length of said first side; and

a flexible circuit secured on at least said first side of said print cartridge body, said flexible circuit having contact pads formed thereon for contacting corresponding electrodes in an ink printer, said flexible circuit having conductive traces terminating in said contact pads for connection to a printhead, said flexible circuit having a width larger than a width of said valley and so that a middle portion of said flexible circuit running a length of said flexible circuit secured to said first side overlies said valley, none of said contact pads on said flexible circuit being formed in said middle portion of said flexible circuit where said flexible circuit overlies said valley.

9. The system of claim 8 wherein said traces run between rows of contact pads in a direction perpendicular to a lengthwise centerline of said flexible circuit when contacting contact pads along outer edges of said flexible circuit.

10. The system of claim 9 wherein said contact pads formed in a row along said outer edges of said flexible circuit are staggered to provide space between contact pads in adjacent rows for said traces to run to contact said contact pads formed in a row along said outer edges.

11. The system of claim 8 wherein said at least one receptacle comprises a plurality of receptacles, and wherein said print cartridge is a first print cartridge, installed in one of said receptacles, said system also comprising:

a second print cartridge, installed in another of said receptacles, said second print cartridge comprising;

a second print cartridge body including a first side having a depressed valley along a middle portion of said first side running along a length of said first side; and

a flexible circuit secured on at least said first side of said second print cartridge body, said flexible circuit having contact pads formed thereon for contacting corresponding electrodes in an ink printer, said flexible circuit having conductive traces terminating in said contact pads for connection to a printhead, said flexible circuit having a width larger than a width of said valley and so that a middle portion of said flexible circuit running a length of said flexible circuit secured to said first side overlies said valley, none of said contact pads on said flexible circuit being formed in said middle portion of said flexible circuit where said flexible circuit overlies said valley.