Lift assembly including a reaction switch
US4407623A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 1980 |
| Grant date | Oct 4, 1983 |
| Priority date | — |
| Expiry date | Oct 24, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S414/134
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A lift system for a transit vehicle includes a stationary main frame secured within a door recess of the vehicle and a side frame that is movable relative to the main frame. An articulated platform including steps pivotally secured to the side frame and scissor linkage pivotally and slideably connected to the main frame is also included. The lift system also includes a reaction switch coupled to the main frame to sense torque imparted to the main frame upon engagement of the platform with an obstacle such as a curb or the ground. If sufficient torque is created due to contact of the platform with an obstruction, the reaction switch is actuated to terminate further downward movement of the platform thereby preventing destruction of the system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.