Abstract: A magnetic field measurement system including a pick-up coil is not moved but fixed. Strips of superconducting material are arranged in a plane with narrow slits between the strips. The strips are moved very near the pick-up coil along the plane. From output variations of a SQUID magnetometer during the movement, a magnitude of a static field perpendicular to the plane of the strips is obtained.
Type:
Grant
Filed:
September 19, 1991
Date of Patent:
February 2, 1993
Assignees:
Research Development Corporation, Junpei Yuyama, Qiquan Geng
Abstract: In a refrigerator having a compressor settled in a room temperature portion and an expander which is connected to the room temperature portion, a piston of the expander is settled in the room temperature portion and pressure variation at a low temperature portion is transferred to the piston through a gas column in a pipe connecting the room temperature portion and the low temperature portion.
Type:
Grant
Filed:
June 28, 1991
Date of Patent:
January 26, 1993
Assignees:
Research Development Corporation of Japan, Junpei Yuyama
Abstract: A head with a pick-up coil is attached to a supporter so that the head is freely movable along the direction perpendicular to the surface of a superconductor. Fluid spouted from the spout hole of the head maintains the height (gap space) of the head from the surface. The head is firmly fixed to the supporter in the direction along the surface. Since the relative position of the head in the direction along the surface of the superconductor is changable by drive means for moving the superconductor or the head, the distribution of the magnetic flux which is trapped in the superconductor is measured by scanning the surface of the superconductor with pick-up coil.
Type:
Grant
Filed:
March 16, 1990
Date of Patent:
October 1, 1991
Assignees:
Research Development Corporation of Japan, Junpei Yuyama, Humio Naruse