Cassette detection device

1. A cassette mounting detection device comprising:

a cassette unit comprising a plurality of trays on which at least one cassette is mounted;

a connector unit configured to receive a first signal indicating that the at least one cassette has been mounted on at least one of the plurality of trays of the cassette unit or a second signal indicating that the at least one cassette has not been mounted on the plurality of trays of the cassette unit through a first transmission terminal of each tray of the plurality of trays; and

a main board unit configured to detect whether the at least one cassette has been mounted on at least one of the trays and on which tray of the plurality of trays of the cassette unit the at least one cassette has been mounted based on the first or second signal transmitted from the connector unit through a second transmission terminal,

wherein the first and second signals are static;

wherein either the first signal or the second signal is outputted as an output signal from each of the plurality of trays,

wherein each output signal is directly transferred to the main board unit through the connector unit,

wherein each of the at least one cassette comprises:

an input unit configured to receive a power supply voltage that varies the first and second signals according to whether the at least one cassette has been mounted on the plurality of trays; and

a switching unit configured to generate the first or second signal based on the power supply voltage,

wherein the switching unit comprises a plurality of open collectors (OC) corresponding to the trays on which the at least one cassette is mounted.

2. The cassette mounting detection device of claim 1 , wherein each of the trays is matched with the first transmission terminal.

3. The cassette mounting detection device of claim 1 , wherein when one cassette of the at least one cassette is mounted on one tray of the plurality of trays, the cassette is connected to a ground such that a first output signal of the OC corresponding to the tray on which the one cassette has been mounted becomes a low level, a second output signal of the OC corresponding to trays that no cassette has been mounted on becomes a high level, and the first signal generated through a logical operation between the first and second output signals becomes a low level and is transmitted to the connector unit through the first transmission terminal.

4. The cassette mounting detection device of claim 3 , wherein when the one cassette is mounted on the tray, the input unit is connected to the ground such that an output signal thereof becomes the low level, a first output signal of the OC corresponding to the trays that no cassette has been mounted on becomes the low level, a second output signal of the OC corresponding to the trays that no cassette has not been mounted on becomes the high level based on a pull-up resistor, and the first signal generated through a logical operation between the first and second output signals of the OCs becomes the low level and is transmitted to the connector unit through the first transmission terminal.

5. The cassette mounting detection device of claim 1 , wherein the main board unit further comprises:

a connector configured to receive the first or second signal through the second transmission terminal.

6. The cassette mounting detection device of claim 5 , wherein the main board unit detects whether the cassette has been mounted on a tray, when the first signal is received through the connector, and detects on which tray of the plurality of trays the cassette of the at least one cassette has been mounted according to the second transmission terminal which receives the first signal.

7. The cassette mounting detection device of claim 1 , wherein the connection unit comprises at least one connector corresponding to the at least one cassette, respectively.

8. The cassette mounting detection device of claim 1 , wherein the first transmission terminal and the second transmission terminal are electrically connected to each other.

9. The cassette mounting detection device of claim 1 , wherein the first signal comprises a low-level signal, and the second signal comprises a high-level signal.

10. A cassette mounting detection device comprising:

a main board unit comprising a first input unit configured to receive a power supply voltage for varying an output signal according to whether a cassette of at least one cassette is mounted on a tray and a first connector configured to receive an output signal based on whether the cassette is mounted on the tray; and

a cassette unit connected to the main board unit, and comprising a second input unit configured to receive a power supply voltage for varying the output signal according to whether the cassette is mounted on the tray, a plurality of switching units respectively corresponding to the at least one cassette and each switching unit of the plurality of switching units configured to output a signal that is determined according to a signal of a mounted cassette, and a second connector configured to receive the output signal of the switching unit through one transmission terminal,

wherein the cassette unit has the at least one cassette, the at least one cassette storing medium therein,

wherein the output signal is directly transferred to the main board unit through the first connector and the second connector,

wherein the output signal is static, and

wherein each of the plurality of switching units comprises a plurality of open collectors (OC) corresponding to the tray on which the at least one cassette is mounted.