A liquid ejection apparatus includes a housing provided at least with an upper surface and side surfaces, and a liquid tank that is arranged in the housing and is refillable with a liquid from outside. A display unit that indicates a remaining liquid amount in the liquid tank is arranged at least at one of joining portions each joining the upper surface to one of the side surfaces.

A recording apparatus 101 includes a liquid storage portion 46 configured to store liquid, a recording head 22 that ejects liquid supplied from the liquid storage portion 46 onto the medium, and a light emitting unit 301 configured to emit light, wherein the liquid storage portion 46 has a float 48 configured to float on liquid in the liquid storage portion 46 and to move according to movement of liquid surface LS while maintaining a posture, and a front surface 43F in which the liquid in the liquid storage portion 46 is visually checkable from outside the liquid storage portion 46, wherein the float 48 has a front surface 48a that by receiving the light from the light emitting unit 301, appears luminous when viewed from a direction facing the front surface 43F.

A printing-fluid cartridge is inserted into a prescribed insertion space of a cartridge-attachment section in an insertion direction crossing a gravitational direction to be attached thereto in an attached posture. The printing-fluid cartridge includes: a housing including a storage chamber, a supply portion having a supply hole, an electrical interface disposed at an upper surface of the housing, and an interfering surface. The interfering surface is positioned upward of the storage chamber and extends in a widthwise direction of the housing. The interfering surface is positioned downward and frontward relative to the electrical interface and is configured to abut against a projection provided at another insertion space different from the prescribed insertion space of the cartridge-attachment section during an insertion of the printing-fluid cartridge into the another insertion space.

A printer includes an ink tank, a print head performing printing by using ink in the ink tank; a light source irradiating an inside of the ink tank with light; a sensor detecting light incident from the ink tank during a period in which the light source emits light; and a background plate facing the light source and the sensor in the ink tank.

An image recording apparatus includes a controller configured to: (a) when a remaining amount of ink at the time of receiving a recording start instruction to start image recording on one recording medium is equal to or less than a predetermined amount and a calculated ink remaining amount is less than a required ink amount, not to start the image recording; and (b) when the remaining amount of ink at the time of receiving the recording start instruction is more than the predetermined amount, start the image recording according to the recording start instruction and, during the image recording according to the recording start instruction, when the remaining amount of ink is equal to or less than the predetermined amount and the calculated ink remaining amount is equal to or less than a threshold, interrupt the image recording.

A tank set includes: tanks arranged in a predetermined direction, each of the tanks being composed of a casing including: a liquid storage chamber defined by mutually opposing two surfaces and configured to store liquid; an inlet provided to inject the liquid into the liquid storage chamber; and a liquid outflow port through which the liquid flows out from the liquid storage chamber to a liquid-consuming unit. Each of the two surfaces extends in a direction intersecting the predetermined direction, and is at least partially composed of a film.

An ink-jet printing apparatus includes an ink-cartridge mounting unit to which an ink cartridge having a first ink chamber containing ink is to be mounted, and a second ink chamber. The second ink chamber stores ink supplied from the first ink chamber. The ink-jet printing apparatus is configured such that, in a case where the ink cartridge is mounted to the ink-cartridge mounting unit, the second ink chamber can be viewed from outside of the ink-jet printing apparatus. An equation 0.5≤L≤d≤1.2 L is satisfied, where d is a length of the second ink chamber, and L is a length of the ink cartridge in a direction in which the ink cartridge is inserted into the ink-jet printing apparatus.

Aspects of a disclosure relates to a liquid discharge device enables previously disabled liquid discharge through a head after a cartridge including a first liquid chamber is replaced and before the liquid level in a second liquid chamber of a tank reaches a predetermined level or higher. Another aspects of the disclosure relates to a liquid discharge device that deactivates an alarm after a cartridge including a first liquid chamber is replaced and before the liquid level in a second liquid reaches a predetermined level or higher.

A detection method for a liquid level of a storage tank is provided. The detection method determines that an optical sensor is for a liquid level detection purpose when a sensing value to a tank object is consistent with a first threshold condition. The detection method further determines the optical sensor as valid on liquid level detection when sensing values respectively corresponding to statuses of print material and non-print-material are consistent with a second threshold condition. During printing, the detection method starts/stops pouring print material into a storage tank when the sensing value of the optical sensor is consistent with a third threshold condition correspondingly.

A liquid cartridge configured to be inserted in a frontward direction to a printer includes: a housing; a liquid supply portion; a circuit board; a plate; and a detection portion. The circuit board includes an electrode group facing upward in an upright posture of the liquid cartridge. The electrode group includes a first electrode, a second electrode, and a third electrode for grounding. The first to third electrodes are arrayed in a lateral direction crossing the frontward direction and a gravitational direction such that the third electrode is positioned between the first and second electrodes. In the upright posture of the liquid cartridge, the plate and the detection portion are respectively positioned upward and rearward relative to the circuit board. Each of the third electrode and an upper portion of the plate is positioned a datum plane extending in the frontward direction and in the gravitational direction.