Personnel lift with automatic set-up transport wheel
US5875869A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1996 |
| Grant date | Mar 2, 1999 |
| Priority date | — |
| Expiry date | Oct 15, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66F11/04
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A personnel lift (20) including a three-wheeled transport in which a rear or transport wheel (30) is connected to a lever arm or handle (32) that is designed to raise and lower the transport wheel (30). Pulling the handle (32) downward drops the transport wheel (30) to ground level raising the support legs (34) off the ground. Raising the handle (32) lifts the transport wheel (30) off the ground, dropping the support legs (34) onto the ground. An electric interlock system is utilized to prevent the vertical lift assembly (24) of the personnel lift (20) from being used when the support legs (34) are not on the ground. The electric interlock system includes three switches (89, 104a, 104b), all of which must be closed in order for the aerial work platform (22) to be elevated. Two of the switches (104a, 104b) are operated by the support legs (34). The switches (104a, 104b) in the support legs (34) are closed when the support legs are in full contact with the ground. The third switch (89) is closed when the handle (32) is in a raised position. A mechanical handle locking mechanism (62) prevents a user from lowering the transport wheel (30) and moving the personnel lift (20) when the aer…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.