Control for hopper loader for granular materials
US4066245A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 30, 1976 |
| Grant date | Jan 3, 1978 |
| Priority date | — |
| Expiry date | Apr 30, 1996 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C31/02
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A versatile control for a plural-material vacuum hopper loader comprising a blowback timer which generates a blowback enabling signal for a time interval T2, a blowback signal generator which develops a series of blowback pulse signals of adjustable duration, and blowback logic which actuates an air supply to apply pulses of air to the hopper loader during interval T2. A fill timer generates a fill enabling signal over a time interval T3, and a fill signal generator develops a repeating sequence of fill actuating signal pulses of adjustable relative duration; the fill enabling signal energizes an evacuation apparatus to evacuate the hopper continuously during interval T3 whereas fill logic actuates fill control valves (one for each material) in the repeating sequence of the fill actuating signal pulses throughout the same interval. Each timer effectively resets the other; for a hopper loader using a local blower as the evacuating apparatus, an additional coastdown (idle) timer is used to afford an idle time T1 between intervals T3 and T2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.