Shutter for a valve and corresponding valve for controlling an air flow and relative valve

A valve for controlling an air flow, comprising:

• a body defining an inlet opening for air flow, an outlet opening for air flow, and a pair of walls defining a valve seat between the inlet opening and the outlet opening;
• the inlet opening having an inlet mouth that opens into an interior of the body and the outlet opening having an outlet mouth that opens into the interior of the body;
• a cylindrically-shaped shutter positioned in the valve seat and selectively rotatable about an axis to control the air flow;
• the cylindrically-shaped shutter comprising an outer surface disposed about the axis and extending along an outer circumference of the shutter;
• and
• the outer surface of the shutter comprising a first curved portion shaped eccentrically relative to the axis and extending along the outer circumference of the shutter to define, together with the pair of walls defining the valve seat, at least one first passage for the air flow, the at least one first passage being fluidly connectable to the inlet opening;
• the outer surface of the shutter comprising a second curved portion shaped eccentrically relative to the axis and extending along the outer circumference of the shutter to define, together with the pair of walls defining the valve seat, a second passage for the air flow, the second passage being fluidly connectable to the outlet opening;
• a through hole passing through the shutter and having a longitudinal extent parallel to the axis, the through hole opening to the outer surface of the shutter at a first end of the through hole, the first end of the through hole including first and second diametrically opposite points as seen in a plane perpendicular to the axis and perpendicular to the longitudinal extent of the through hole;
• the through hole opening to the outer surface of the shutter at a second end of the through hole, the second end of the through hole including diametrically opposite third and fourth points as seen in the plane;
• the first curved portion of the outer surface that is shaped eccentrically relative to the axis including, in the following order in a circumferential direction as seen in the plane:
• i) a first stretch which extends at a gradually decreasing radial distance from the axis, the first stretch extending from the first point to the second point;
• ii) a first relative section extending at a minimum radial distance from the axis to define a minimum radial size of the first curved portion of the outer surface of the shutter;
• and iii) a second stretch which extends at a gradually increasing radial distance from the axis;
• and
• the second curved portion of the outer surface that is shaped eccentrically relative to the axis including, in the following order in a circumferential direction as seen in the plane:
• i) a third stretch which extends at a gradually decreasing radial distance from the axis, the third stretch extending from the third point to the fourth point;
• ii) a second relative section extending at a minimum radial distance from the axis to define a minimum radial size of the second curved portion of the outer surface of the shutter;
• and iii) a fourth stretch which extends at a gradually increasing radial distance from the axis.