Proximity control system
US4947759A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 2, 1988 |
| Grant date | Aug 14, 1990 |
| Priority date | — |
| Expiry date | Dec 2, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB61L3/14
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A proximity switching system comrising a plurality of self-propelled vehicles mounted in tandem on a track and carrying magnetic proximity switches for controlling the vehicle propulsion. Each vehicle has a first magnet mounted on the front end at a first position, a second magnet mounted on the back end at a second position, a first magnetic reed switch mounted on the front end at a position congruent with the second position on the back end, and a second magnetic reed switch mounted on the back end at a position congruent with the first position on the front end. A pair of electric rails are mounted next to the track. Each vehicle includes contacts for receiving voltages on the rails. A DC motor drives the vehicles on the track in one of two directions dependent on the polarity of the voltages, and for not driving the vehicles in response to the closure of the first switch when the voltage has one polarity and in response to the closure of the second switch when the voltage has an opposite polarity. The magnet on a given vehicle has two functions: first, it will close the reed switch on an approaching vehicle if it comes within a predetermined distance from the given vehicle and …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.