Extended dwell shock sensing device
US4877927A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 6, 1989 |
| Grant date | Oct 31, 1989 |
| Priority date | — |
| Expiry date | Apr 6, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H35/147
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An extended dwell shock sensing device (10) is constructed to operate in two stages. A carriage (34) that includes a magnet (40) is slidably mounted between a first abutment (20) and a second abutment (22). The carriage (34) also includes a cradle (52) in which a non-magnetic mass (54) is slidably mounted between a first wall (53) and a second wall (55). At a rest position, the carriage (34) is biased away from the second abutment (22) by a spring (50) and the non-magnetic mass (54) is biased away from the second wall (55) by a spring (58). A reed switch (24) is mounted to be responsive to the position of the magnet (40). Upon application of an acceleration force, the shock sensing device (10) operates in two stages. In a first stage, the carriage (34) travels to a position where it approaches the second abutment (22), and activates the reed switch (24). In a second stage, the non-magnetic mass (54) travels toward the second wall (55). The inertia of the non-magnetic mass (54) resisting a rapid change in the return direction of the carriage (54), combined with the relatively long distance to travel back to the first stage position extends the time that the reed switch (24) stays ac…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.