Indoor unit for air-conditioning apparatus

1. An indoor unit for an air-conditioning apparatus, comprising:

a casing having an air inlet formed in an upper surface of the casing and an air outlet formed below the air inlet;

a plurality of axial-flow fans provided on a downstream side of the air inlet;

a heat exchanger provided at a position located on a downstream side of the plurality of axial-flow fans and on an upstream side of the air outlet;

a plurality of filters provided to the air inlet and configured to remove dust from air sucked into the casing by the plurality of axial-flow fans;

a cleaning mechanism provided on one end portion side of the plurality of filters in a right-and-left direction, or above the plurality of axial-flow fans and configured to clean the plurality of filters through relative movement to the plurality of filters, the cleaning mechanism includes a brush;

a dust box including a dust collecting portion configured to collect the dust removed by the cleaning mechanism, the dust box being provided on the upstream side of the plurality of axial-flow fans so as to be freely mountable and dismountable in a fore-and-aft direction,

the plurality of filters being arranged side by side in the right-and-left direction, and the plurality of axial-flow fans being arranged side by side in the right-and-left direction,

the dust box being arranged at a position (a) between at least two adjacent filters among the plurality of filters in plan view and (b) between at least two adjacent axial-flow fans among the plurality of axial-flow fans in plan view; and

a plurality of cartridges configured to respectively mountably and dismountably accommodate the plurality of filters, wherein

each of the plurality of cartridges has an opening port formed in an end portion of the each of the plurality of cartridges in the right-and-left direction on a side opposed to the dust box, the opening port is configured to expose each of the plurality of filters to the brush during cleaning of the each of the plurality of filters,

the each of the plurality of cartridges has a ventilation port formed in an upper surface of the each of the plurality of cartridges and a ventilation port formed in a lower surface of the each of the plurality of cartridges, the ventilation ports being formed at positions opposed to each of the plurality of axial-flow fans; and

the each of the plurality of cartridges is provided so as to be freely mountable into and dismountable from the casing in the fore-and-aft direction.

2. The indoor unit for an air-conditioning apparatus of claim 1 , further comprising:

a filter drive shaft configured to move each of the plurality of filters in the right-and-left direction; and

a filter drive motor configured to drive the filter drive shaft, wherein:

the dust box includes the cleaning mechanism; and

the cleaning mechanism further comprises:

a brush drive shaft, to which the brush is mounted, the brush drive shaft being configured to rotate or swing the brush.

3. The indoor unit for an air-conditioning apparatus of claim 2 , wherein the each of the plurality of filters is configured to be moved toward the end portion of the each of the plurality of cartridges on a side where the dust box is arranged and to be reversed at the end portion.

4. The indoor unit for an air-conditioning apparatus of claim 2 , wherein the filter drive motor is arranged behind the dust box.

5. The indoor unit for an air-conditioning apparatus of claim 2 , wherein

the each of the plurality of cartridges includes the filter drive shaft.

6. The indoor unit for an air-conditioning apparatus of claim 5 , wherein:

the each of the plurality of cartridges comprises:

an upper frame forming the upper surface of the each of the plurality of cartridges;

a lower frame forming the lower surface of the each of the plurality of cartridges; and

an intermediate frame provided between the upper frame and the lower frame; and

an upper traveling path for the each of the plurality of filters is formed between the upper frame and the intermediate frame, and a lower traveling path for the each of the plurality of filters is formed between the intermediate frame and the lower frame.

7. The indoor unit for an air-conditioning apparatus of claim 5 , wherein:

the casing comprises a placement portion on which the each of the plurality of cartridges is to be placed;

the each of the plurality of cartridges comprises:

an upper frame forming the upper surface of the each of the plurality of cartridges; and

a lower frame forming the lower surface of the each of the plurality of cartridges; and

an upper traveling path for the each of the plurality of filters is formed between the upper frame and the lower frame, and a lower traveling path for the each of the plurality of filters is formed between the lower frame and the placement portion.

8. The indoor unit for an air-conditioning apparatus of claim 6 , wherein the each of the plurality of filters is configured to be located in the upper traveling path in an operating state and to be moved, during cleaning, toward the end portion of the each of the plurality of cartridges on the side where the dust box is arranged and reversed at the end portion so as to be moved into the lower traveling path.

9. The indoor unit for an air-conditioning apparatus of claim 5 , wherein the each of the plurality of cartridges comprises a handle at least on a front surface of the each of the plurality of cartridges.

10. The indoor unit for an air-conditioning apparatus of claim 5 , wherein the each of the plurality of cartridges is formed into a fore-and-aft symmetrical shape.

11. The indoor unit for an air-conditioning apparatus of claim 1 , wherein an upper surface of the dust box forms a part of the upper surface of the casing.