Ball valve assembly

A ball valve assembly comprising:

• a ball element arranged to be rotated by rotation of a shaft in engagement with the ball element, the ball element including:
• first and second flow channels defined therethrough;
• a first inlet port at a first end of said first flow channel;
• a first outlet port at a second end of the first channel;
• a second inlet port at a first end of the second flow channel;
• and
• a second outlet port at a second end of the second channel;
• wherein each of the first and the second channels defines a bend within the ball element and wherein the first inlet port, the second inlet port, the first outlet port and the second outlet port are substantially evenly spaced around the ball element;
• wherein the ball element is driven by a cam shaft having a cammed external profile, the assembly further comprising switch means arranged to cooperate with the cam shaft to provide an indication of the rotational position of the cam shaft;
• wherein the switch means comprises a plurality of microswitches arranged around and in proximity to the cammed external profile of the cam shaft such that the cammed external profile contacts and activates said switches at predetermined rotational positions of the shaft;
• wherein the microswitches are arranged to switch in response to rotation of the cam shaft by 45 degrees;
• wherein the switch means comprises two sets of microswitches, each set of microswitches comprising two microswitches arranged substantially 90 degrees apart around the circumference of the shaft, wherein the sets of microswitches are separated axially from each other with respect to the axis of the cam shaft;
• and
• wherein the cammed external profile of the cam shaft comprises a first set of recesses arranged to cooperate with a first of the sets of microswitches, and a second set of recesses spaced axially from the first set and arranged to cooperate with a second of the sets of microswitches.