PURPOSE: To manufacture a pump and an internal combustion engine by alternately connecting curves being base lines in a symmetrical form to make a cylinder-like part while curves being twice the size of the base lines and being in a face-to-face relation are connected to each other in the cylinder line part to make a pistonlike part, thereby enabling extension/ contraction of space between projecting portions of the piston-like part to be made when the piston-like part is moved, and connecting upper and lower portions of the cylinder-like part and the piston-like part to each other, so that they can carry out infinite motion.

CONSTITUTION: A left circular wave type base line 3 is arranged in a left cylinder 1 by connecting circular curves to each other, and right circular wave type base line 4 is arranged in a right cylinder 2, so that both base lines 3, 4 are symmetrically formed. Circular curves which are formed by twice of the curve and positioned in a face-to-face relation are connected to each other in parallel on the left side of a piston 5 so as to form a left relative circular curve, a piston in which a half-shifted type of symmetrical right relative circular curve is arranged on a right side is inserted in the cylinder. The left circular wave type base line 3 and the piston projection part lefts 8, 9 are brought in contact with each other while the right circular wave type base line 4 is brought in contact with the piston projection part rights 10, 11, and then the piston is moved, whereby space between the piston projection part lefts 8, 9 is increased, and space between the piston projection rights 10, 11 is decreased.