Mr. Richard Phillips Feynman, a famous genius scientist, introduced a Brownian ratchet in his book “The Feynman Lectures on Physics” (see Figure 1). The Brownian ratchet is also referred to as Feynman’s ratchet, Feynman’s thermal ratchet and the like.

The Brownian ratchet is a submicron-scale micromachine in which components move randomly by Brownian motion. The micromachine can be manufactured by using microfabrication technologies such as semiconductor fabrication technologies, nanotechnologies and molecular machine technologies.

The Brownian ratchet is a micromachine extracting useful work from Brownian motion. Details of the Brownian ratchet are omitted here. Please search the internet etc. for details of the Brownian ratchet.

As an important point, Mr. Feynman denies that the impeller and the ratchet rotate continuously in one direction. However, he and many other scientists have agreed the impeller and the ratchet rotate randomly. Naturally, the impeller and the ratchet rotate randomly because the Brownian motion is the random movement.

Figure 2 shows a micromachine of the present invention. The present invention provides the micromachine extracting useful energy from the Brownian motion. The present invention realizes Maxwell’s demon using the Brownian motion. The micromachine shown in Figure 2 comprises a first room and a second room. In the first room, an impeller, a permanent magnet and a coil are provided. The permanent magnet and the impeller are fixed to the same rotating shaft. The coil is disposed near the permanent magnet. Submicron-scale strong permanent magnets are being developed by scientists at the University of Tokyo Japan. A resistor is provided in the second room.

Molecules randomly collide with the impeller. As shown in Figures 3-5, the collision of molecules with the impeller causes the impeller to randomly rotate. The rotation of the impeller is transmitted to the permanent magnet via the rotating shaft, and the permanent magnet rotates with the impeller.

When the permanent magnet rotates, electric currents are generated in the coil by electromagnetic induction. The electric currents generated by the electromagnetic induction are supplied to the resistor of the second room through the wiring. As shown in Figures 6-8, the resistor which is supplied the electric currents generates heat and the temperature of the second room rises. For example, even if the temperatures of the first and second rooms are uniform at first, a temperature difference is generated between the first room and the second room. That is, the entropy can be reduced. Thereby, the Maxwell’s demon can be realized. The Maxwell’s demon actually exists. Of course, if the generated electric currents are output to the outside, the generated electric powers can be used by external devices. I will say once again. The Maxwell’s demon actually exists.