Dust and allergen control for surface cleaning apparatus

1. A surface cleaning apparatus comprising:

a) an air flow path extending from a dirty air inlet to a clean air outlet and comprising a main air treatment member having a dirt collection region having an openable door; and,

b) a main suction motor provided in the air flow path,

wherein the dirt collection region is exposed to sub-atmospheric pressure when the openable door is in an open position, and

wherein the main suction motor is utilized to provide the sub-atmospheric pressure to the dirt collection region.

2. The surface cleaning apparatus of claim 1 wherein the dirt collection region is automatically exposed to sub-atmospheric pressure when the openable door is opened.

3. The surface cleaning apparatus of claim 1 wherein the dirt collection region is automatically exposed to sub-atmospheric pressure prior to the openable door opening.

4. The surface cleaning apparatus of claim 1 wherein the main suction motor is operable in a cleaning mode in which the main suction motor is used to draw air from the dirty air inlet, through the main air treatment member to the clean air outlet and an emptying mode in which the main suction motor is utilized to provide the sub-atmospheric pressure to the dirt collection region and the main suction motor is operated at a lower power level during the emptying mode.

5. The surface cleaning apparatus of claim 4 wherein the main suction motor creates an air flow of 0.1 Cubic Feet per Minute (CFM) to 1.5 CFM per square inch of opening area during the emptying mode.

6. The surface cleaning apparatus of claim 1 wherein the main suction motor is operable in a cleaning mode in which the main suction motor is used to draw air from the dirty air inlet, through the main air treatment member to the clean air outlet and an emptying mode in which the main suction motor is utilized to provide the sub-atmospheric pressure to the dirt collection region, wherein a first pre-motor filter is positioned in a main downstream portion of the air flow path from the main air treatment member to the main suction motor during the cleaning mode and an alternate air treatment member is provided in an alternate downstream air flow path from the main air treatment member to the main suction motor during the emptying mode.

7. The surface cleaning apparatus of claim 6 wherein the surface cleaning apparatus comprises a main closure member associated with the main downstream portion of the air flow path and an alternate closure member associated with the alternate downstream air flow path, each of the main closure member and the alternate closure member moveable between an open position and a closed position wherein, during the cleaning mode, the main closure member is open and the alternate closure member is closed whereby the main suction motor is in air flow communication with the main air treatment member via the main downstream portion of the air flow path and in the emptying mode the main closure member is closed and the alternate closure member is open whereby the main suction motor is in air flow communication with the main air treatment member via the alternate downstream air flow path.

8. The surface cleaning apparatus of claim 6 wherein the alternate air treatment member comprises a filter.

9. The surface cleaning apparatus of claim 1 wherein the main air treatment member comprises a cyclone.

10. The surface cleaning apparatus of claim 9 wherein the dirt collection region comprises a dirt collection chamber exterior to the cyclone.

11. A surface cleaning apparatus comprising:

a) an air flow path extending from a dirty air inlet to a clean air outlet and comprising a main air treatment member having a dirt collection region having an openable door wherein the dirt collection region has an opening when the openable door is in an open position;

b) a main suction motor provided in the air flow path; and,

c) an emptying mode suction motor which provides sub-atmospheric pressure to the dirt collection region when the openable door is in an open position,

wherein the emptying mode suction motor draws air from the dirt collection region other than through the opening when the openable door is in an open position.

12. The surface cleaning apparatus of claim 11 wherein the emptying mode suction motor produces a sub-atmospheric pressure less than a pressure in the main air treatment member during operation of the main suction motor.

13. The surface cleaning apparatus of claim 11 wherein the emptying mode suction motor creates an air flow of 0.1 CFM to 1.5 CFM per square inch of opening area during the emptying mode.

14. The surface cleaning apparatus of claim 11 wherein a portion of the air flow path connects the emptying mode suction motor in air flow communication with the dirt collection region during an emptying mode of the dirt collection region.

15. The surface cleaning apparatus of claim 14 wherein the portion of the air flow path is positioned upstream of the main air treatment member.

16. The surface cleaning apparatus of claim 15 wherein an emptying mode air treatment member is positioned in the portion of the air flow path.

17. The surface cleaning apparatus of claim 16 wherein the surface cleaning apparatus comprises a main closure member associated with the portion of the air flow path, the main closure member being moveable between an open position and a closed position wherein, during the cleaning mode, the main closure member is closed whereby air travels from the dirty air inlet to the main air treatment member without contacting the emptying mode air treatment member and, in the emptying mode the main closure member is opened whereby air travels from the main air treatment member and through the emptying mode air treatment member.

18. The surface cleaning apparatus of claim 16 wherein the emptying mode air treatment member comprises a filter.