Sifting screen
US5819952A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 1997 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Jan 9, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB07B1/48
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A sifting screen is described comprising a rigid frame, a first woven cloth of hard wearing metal wire, stretched thereacross and secured thereto, and a second woven cloth having a coarser mesh than the first cloth and being woven from an elongate material of greater cross-section than the first, also stretched across the frame, and secured thereto, below the first cloth, to support the latter against sagging. In accordance with the invention, at least the wearing surface of the material from which the lower cloth is woven is selected to be significantly less hard wearing than that from which the upper cloth is woven, so that wear due to rubbing and vibration during use, occurs to a greater extent in the lower cloth than in the upper cloth. In one example the upper cloth is woven from stainless steel wire and the lower from phosphor bronze wire. In another example the lower cloth is of wire having a coating of an epoxy based material, or Teflon (TM), or Molybdenum Disulphide. In another example the lower cloth is formed from a plastics material or Kevlar (TM) or carbon fibre. The frame may be formed from glass reinforced gas blown polypropylene reinforced by elongate metal reinforc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.