<p>Provided is a cam motor which is easy to manufacture and maintain. The cam motor is provided with: a main shaft (2) which is arranged so as to be able to rotate around the shaft centre; a cam disc (3) which is arranged on the main shaft (2) so as to be concentric with said main shaft (2) and on the outer periphery of which a cam surface (3a) is formed; a cylinder block (4) which is ring shaped and which is arranged such that the cam disc (3) is positioned inside of the ring; and a plurality of freely reciprocating pistons (42) which are arranged on the inner peripheral side of the cylinder block (4) and the tip sections of which are in contact with the cam surface (3a). The shape of the cam surface (3a) is set such that the cam disc (3) rotates with the reciprocal motion of the pistons (42).</p>
