Damper device and turbomolecular pump with damper device
US6213737A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 16, 1998 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Apr 16, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16C2360/45
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A damper device has a magnet and at least two yokes facing the magnet across gaps. The magnet and the two yokes jointly provide a magnetic circuit such that a magnetic flux flowing from a first magnetic pole of the magnet is divided across one of the gaps into magnetic fluxes which flow into entrance sides of the yokes and back from exit sides of the yokes across another of the gaps into a second magnetic pole of the magnet. The two yokes are mechanically connected rigidly to each other, and a spring means elastically holds the one of the gaps between the first magnetic pole and the entrance sides of the yokes. One of the magnet and the yokes is adapted to be connected to a vibratable member. When the gaps are differentially varied in length by vibration of the vibratable member, the divided magnetic fluxes are changed to generate eddy currents in the yokes and the magnetic poles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.