MACHINE WITH REDUCED CYLINDER FRICTION

A machine having a cylinder (103), the configuration of the machine being such that a body portion (109) of a piston (107) of the machine periodically engages an inner surface (105) of the cylinder (103) during operation of the machine, this engagement defining a contact zone between the body portion (109) of the piston (107) and the inner surface (105) of the cylinder (103), the inner surface (105) of the cylinder (103) having an enhanced bearing region comprising one or more recesses (117) indented into the inner surface (105), the enhanced bearing region being smaller than the inner surface (105) of the cylinder (103) and being substantially centered on the contact zone.