Self cleaning rotary screen for the cooling air inlet of an engine enclosure

A self cleaning filter screen for filtering out large particulate matter from an air stream, said screen comprising:

• a filter screen arranged to intercept an air stream so that air to be filtered flows through the screen;
• a frame on which the screen is rotatably mounted by a bearing means, the frame comprises a pivotable door that is coupled to a larger structure, the door is provided with an opening having a smaller cross sectional area than the cross sectional area of the filter screen, the filter screen is adapted and constructed to fit over the opening to prevent unfiltered air from passing through the opening, the pivotable door defines a pivot axis adjacent an edge of the door;
• an endless belt operatively coupling the filter screen to transmit rotational motion to the screen and is provided with cross sectional centerpoint;
• and
• first and second freely rotatable sheaves are mounted to the door and are located on the door so that a tangent of the centerpoint of the endless belt when coupled to the outer periphery of both sheaves forms a tangent axis that is substantially aligned with the pivot axis.

A self-propelled agricultural combine for harvesting and threshing a crop on a field, the combine comprising:

• a chassis having a ground engaging assembly and a propulsion means for propelling the combine across a field;
• a harvesting means for collecting a crop from a field extends outwardly from the chassis and is powered by the propulsion means;
• a threshing and separating means for separating grain from chaff of a crop harvested from a field is located inside the chassis and is powered by the propulsion means;
• a planar filter screen is located adjacent to the propulsion means for filtering large particulate material from cooling air directed to the propulsion means, the filter screen is arranged to intercept a cooling air stream so that air to be filtered flow through the screen, the filter screen is provided with a circular flange having an internal surface and an external surface, the external surface being provided with a first external groove and the internal surface is provided with an internal groove, the filter screen is rotatably mounted to the chassis by a bearing means which engages the internal groove, and an endless belt extending about the circular flange in the first external groove and a propulsion sheave operatively coupled to the propulsion means thereby transmitting rotational motion to the screen.

A self-propelled agricultural combine for harvesting and threshing a crop on a field, the combine comprising:

• a chassis having a ground engaging assembly and a propulsion means for propelling the combine across a field, the propulsion means is also provided with a driving sheave;
• a harvesting means for collecting a crop from a field extends outwardly from the chassis and is powered by the propulsion means;
• a threshing and separating means for separating grain from chaff of a crop harvested from a field is located inside the chassis and is powered by the propulsion means;
• a filter screen is located adjacent to the propulsion means for filtering large particulate material from cooling air directed to the propulsion means, the filter screen is arranged to intercept a cooling air stream so that air to be filtered flows through the screen, the filter screen is mounted on a pivotable door that is pivotally coupled to the chassis and is rotatably mounted to the door by a bearing means, the door is provided with an opening having a smaller cross sectional area than the cross sectional area of the filter screen, the filter screen is adapted and constructed to fit over the opening to prevent unfiltered air from passing through the opening, the pivotable door defines a pivot axis adjacent an edge of the door where it is pivotally coupled to the chassis;
• an endless belt operatively couples the driving sheave to the filter screen for rotating the filter screen, the endless belt having a cross sectional centerpoint;
• and
• a means for arranging the endless belt so that the endless belt does not have to be operatively disengaged when the pivotable door is opened.