Remaining ink detecting device and ink jet head cartridge

An ink jet head cartridge comprising:

• a recording head portion composed of a substrate on which ink emission energy generating elements are disposed;
• an ink tank portion for storing an ink to be supplied to said recording head portion;
• an ink supply passage through which the ink is supplied from said ink tank portion to said recording head portion;
• and
• a residual ink detecting means, part of which is provided in said ink supply passage for detecting the amount of remaining ink,
• wherein said residual ink detecting means includes first and second electrodes and a detecting means for detecting a resistance between said electrodes, wherein said second of said electrodes is provided in said ink supply passage in an area relatively close to said recording head portion, whereas said first of said electrodes is provided in said ink supply passage in an area relatively far from said recording head with said second of said electrodes therebetween, and wherein said second of said electrodes is maintained at a same potential as that of said substrate, whereas said first of said electrodes is maintained at a potential different from that of said of said second electrodes.

An ink jet recording apparatus comprising:

• an ink jet head cartridge including a recording head portion composed of a substrate on which ink emission energy generating elements are disposed, an ink tank portion for storing an ink to be supplied to said recording head portion, an ink supply passage through which the ink is supplied from said ink tank portion to said recording head portion, and first and second electrodes provided in said ink supply passage for detecting the amount of remaining ink, said second of said electrodes being provided in said ink supply passage in an area relatively close to said recording head portion, whereas said first of said electrodes being provided in said ink supply passage in an area relatively far from said recording head with said second of said electrodes therebetween, and said second of said electrodes being maintained at a same potential as that of said substrate, whereas said first of said electrodes being maintained at a potential different from that of said second of said electrodes;
• a means for detecting a resistance between said first and second electrodes;
• and
• a carriage provided in such a manner as to be movable with said ink jet head cartridge mounted thereon.

A device for detecting a quantity of remaining ink, comprising:

• first and second electrodes provided in an ink supply passage which connects an ink tank for storing an ink to a recording head for emitting the ink;
• and
• a detection means for detecting a resistance between said first and second electrodes,
• wherein said first and second electrodes are disposed such that a resistance R.sub.1-3 between said first of said electrodes having a potential different from that of a substrate which constitutes said recording head and said substrate is sufficiently larger than an ink resistance R.sub.1-2 between said first and second electrodes which is obtained when the ink is filled therebetween, and that the resistances R.sub.1-3 and R.sub.1-2 have a relation expressed by R.sub.1-3 /R.sub.1-2 >5, so as to allow the amount of remaining ink to be detected by a measurement of only changes in the resistance between said first and second electrodes.

A device for detecting a quantity of remaining ink, comprising:

• first and second electrodes provided in an ink supply passage which connects an ink tank for storing an ink to a recording head for emitting the ink;
• and
• a detection means for detecting a resistance between said first and second electrodes,
• wherein said first and second electrodes are disposed in said ink supply passage such that a resistance R.sub.1-3 between said first of said electrodes having a potential different from that of a substrate which constitutes said recording head and said substrate is sufficiently larger than an ink resistance R.sub.1-2 between said first and second electrodes which is obtained when the ink is filled therebetween, and that the resistances R.sub.1-3 and R.sub.1-2 have a relation expressed by R.sub.1-3 /R.sub.1-2 >5, so as to allow the amount of remaining ink to be detected by a measurement of only changes in the resistance between said first and second electrodes.

A device for detecting a quantity of remaining ink, comprising:

• first and second electrodes provided at a region for storing ink to be supplied to a recording head for ink emission;
• and
• measurement means for measuring an electric property change between said first and second electrodes obtained as a result of applying a predetermined electric signal between said first and second electrodes,
• wherein one of said first and second electrodes is said recording head and is maintained at substantially a same potential as a supporting member supporting an energy generating element to be driven for ink emission, and the other of said first and second electrodes is maintained at a potential different from said one of said first and second electrodes.

An ink jet cartridge removably held on a recording device, comprising:

• a recording head section for ink emission;
• a tank section for storing ink to be supplied to said recording head;
• and
• first and second electrodes provided within a region in which ink exists between said tank section and said recording head section,
• wherein one of said first and second electrodes is said recording head section and is maintained at a same potential as a supporting member supporting an energy generating element to be driven for ink emission, and the other of said first and second electrodes is maintained at a potential different from said one of said first and second electrodes, and
• wherein said ink jet cartridge detects the quantity of the ink remaining within said tank section, based on measurement of an electric property between said first and second electrodes by said measurement means, responsive to applying an electric signal between said first and second electrodes when said cartridge is mounted on said recording device.