To enable a regenerator to achieve predetermined required performance by adjusting the length of a wound-around resin-made film in accordance with its thickness and making a pressure loss caused by the regenerator constant.

A working medium is moved between a compression space and an expansion space by a piston and a displacer to heat a high temperature side heat transfer head and cool a low temperature side heat transfer head. This regenerator arranged between the compression space and the expansion space is composed of a resin-made film wound-around stacked body 73 constituted by winding the resin-made film 72 around by forming the predetermined distance between the films. A regenerator winding-around device 120 winds the resin-made film around by only the fixed length in a process for measuring the thickness of the resin-made film and a process for deciding the length of the resin-made film to be wound around based on the measured thickness of the resin-made film.