Abstract: An cleaning brush for a pool cleaning apparatus, the cleaning brush that includes: a central portion that has a longitudinal axis; a right handed fin that surrounds a first section of the central portion; a left handed fin that surrounds a second section of the central portion; first protuberances that are oriented in relation to the right handed fin; and second protuberances that are oriented in relation to the left handed fin.

Abstract: A pool cleaning robot, that may include a filter; a first impeller; a driving unit arranged to move the pool cleaning robot; an external housing that comprises a first inlet and a first outlet; a first pump motor arranged to rotate the first impeller; wherein when the first pump motor rotates the first impeller rotates along a first rotational direction causes fluid to be drawn through the first inlet and causes a first portion of the fluid to be filtered by the filter to provide filtered fluid that exits through the first outlet of the housing; wherein when the first pump motor rotates the first impeller rotates along a second rotational direction that is opposite to the first rotational direction, thereby performing a backwash operation of the filter.

Abstract: A pool cleaning apparatus that may include a filter; a entrapment cell; a first impeller; a first pump motor arranged to rotate the first impeller; a driving unit arranged to move the pool cleaning robot; a structural element; and an external housing that comprises a first inlet and a first outlet; wherein the filter and the structural element define a first space that has a spiral portion; wherein the first impeller is arranged to rotate along a first rotational direction; wherein rotation of the first impeller along a first rotational direction causes fluid be drawn through the first inlet and to follow a spiral path within the first space during which a first portion of the fluid is filtered by the filter to provide filtered fluid that exits through the first outlet of the housing; and a second portion of the fluid follows the spiral path until entering the entrapment cell.

Abstract: A pool cleaning robot, that may include a filter; a first impeller; a driving unit arranged to move the pool cleaning robot; an external housing that comprises a first inlet and a first outlet; a first pump motor arranged to rotate the first impeller; wherein when the first pump motor rotates the first impeller rotates along a first rotational direction causes fluid to be drawn through the first inlet and causes a first portion of the fluid to be filtered by the filter to provide filtered fluid that exits through the first outlet of the housing; wherein when the first pump motor rotates the first impeller rotates along a second rotational direction that is opposite to the first rotational direction, thereby performing a backwash operation of the filter.

Abstract: An cleaning brush for a pool cleaning apparatus, the cleaning brush that includes: a central portion that has a longitudinal axis; a right handed fin that surrounds a first section of the central portion; a left handed fin that surrounds a second section of the central portion; first protuberances that are oriented in relation to the right handed fin; and second protuberances that are oriented in relation to the left handed fin.

Abstract: A pool cleaning apparatus that may include a filter; a entrapment cell; a first impeller; a first pump motor arranged to rotate the first impeller; a driving unit arranged to move the pool cleaning robot; a structural element; and an external housing that comprises a first inlet and a first outlet; wherein the filter and the structural element define a first space that has a spiral portion; wherein the first impeller is arranged to rotate along a first rotational direction; wherein rotation of the first impeller along a first rotational direction causes fluid be drawn through the first inlet and to follow a spiral path within the first space during which a first portion of the fluid is filtered by the filter to provide filtered fluid that exits through the first outlet of the housing; and a second portion of the fluid follows the spiral path until entering the entrapment cell.