Controllable brake
US5842547A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1996 |
| Grant date | Dec 1, 1998 |
| Priority date | — |
| Expiry date | Jul 2, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16D2121/20
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A controllable brake (20) including a rotor (28) supported by a shaft (30) which is rotatably supported by bushings (42) received in housing (22). A coil assembly (48) creates a magnetic field within a pole piece (32), which is preferably manufactured from a powdered metal material, which preferably has a density of between about 6.8 and 7.0 gm/cm. A magnetically-soft medium is contained within first and second gaps (86, 88) located between pole piece (32) and rotor (28). In one aspect, a magnetic saturation zone (25) reduces the propensity of magnetizing the shaft (30). In another, the pole halves (24, 26) are received in radially-spaced pole pockets (37) formed in the housing (22) and include an axial bias spring (70) to ensure intimate contact. In another aspect, a lip projection (76) traps fluid (23) between the lip projection (76) and shaft (30) and minimizes fluid exposure to the shaft seal (44). In another aspect, cooling fins (55) or a projection (53) restrains rotation of the housing (22). In another aspect, a spring (46) centers the rotor (28) relative to the housing (22).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.