Shaft mounting assembly

A shaft mounting assembly comprising:

• an elongate shaft comprising an outer surface having a substantially circular cross-section;
• a cylinder having an inner surface defining a bore, the bore housing the shaft, wherein the inner diameter of the cylinder is larger than the outer diameter of the shaft such that a gap is defined between the outer surface of the shaft and the inner surface of the cylinder;
• and,
• a spring comprising a substantially circular discontinuous band having correspondingly shaped axially arcuate inner and outer surfaces, wherein an axial width of the band is less than a width of a groove in an energised state;
• wherein one of the outer surface of the shaft and the inner surface of the cylinder comprises the groove;
• and wherein the groove extends around the circumference of the outer surface of the shaft or the circumference of the inner surface of the cylinder respectively;
• wherein the spring is positioned in the groove such that both axial edges of the band are located within the groove;
• wherein the spring has a de-energised state in which the height of the band is greater than the depth of the groove, so that a portion of the band between the axial edges protrudes out of the groove, and the axial width of the band is less than the width of the groove;
• wherein the spring is compressed within the bore such that the height of the band is reduced in the energised state, and the axial width of the band is increased compared to the de-energised state;
• and
• wherein the shaft is a static piston housed in the cylinder, being non-reciprocating and non-rotatable relative to the cylinder.