Liquid discharge device

1. A liquid discharge device comprising:

a tank comprising a second liquid chamber, the second liquid chamber being connectable to a cartridge, the cartridge comprising a first liquid chamber storing a liquid;

a flow path, one side of the flow path communicated with the second liquid chamber, the other side of the flow path communicated with the first liquid chamber of the cartridge to be connected to the tank;

a head communicated with the flow path;

a liquid level sensor; and

a controller configured to:

discharge ink from the head based on a recording instruction;

receive a first signal from the liquid level sensor in a case a position of a liquid level in the second liquid chamber is equal to or more than a predetermined position;

receive a second signal from the liquid level sensor in a case the position of the liquid level in the second liquid chamber is less than the predetermined position after the ink is discharged from the head based on the recording instruction;

after the second signal is received from the liquid level sensor, determine whether the cartridge is installed in an installation case;

based on determining that the cartridge is installed in the installation case after receiving the second signal from the liquid level sensor, accept a maintenance process of discharging a liquid stored in the second liquid chamber from the head; and

based on receiving the first signal from the liquid level sensor, perform the accepted maintenance process.

2. The liquid discharge device according to claim 1 , wherein the controller is configured to:

in a case the second signal is received from the liquid level sensor during a period where the maintenance process is performed, stop the maintenance process; and

in a case the first signal is received from the liquid level sensor during a period where the performing of the maintenance process is stopped, resume the maintenance process.

3. The liquid discharge device according to claim 1 ; wherein the controller is configured to:

in a case a first elapsed time reaches a first time, not to perform the maintenance process, the first elapsed time being from a time when the cartridge is installed in the installation case until a time when the first signal is received from the liquid level sensor; and

in a case a second elapsed time reaches a second time, perform the maintenance process, the second elapsed time being elapsed time after receiving the first signal from the liquid level sensor.

4. The liquid discharge device according to claim 3 , further comprising:

an alarm,

wherein the controller is configured to, in a case a third elapsed time reaches a third time and the second signal is received from the liquid level sensor without receiving the first signal, activate the alarm, the third elapsed time being elapsed time after determining that the cartridge is installed in the installation case, the third time being longer than the first time.

5. The liquid discharge device according to claim 1 , further comprising:

a pump; and

a cap connected to the pump,

wherein the controller is configured to, in a case of performing the maintenance process, discharge a liquid from a nozzle of the head by driving the pump in a state where the cap covers the nozzle of the head.