Solid material comminution or disintegration – Apparatus – Cooperating comminuting surfaces
Patent
1980-03-05
1982-06-15
Rosenbaum, Mark
Solid material comminution or disintegration
Apparatus
Cooperating comminuting surfaces
241238, 241294, B02C 1818
Patent
active
043346502
DESCRIPTION:
BRIEF SUMMARY
This invention relates to cutters for a rotary shredding machine, and to rotary shredding machines of the kind (hereinafter referred to as a "machine of the kind hereinbefore specified") having a comminuting chamber, a pair of parallel cutter shafts arranged for simultaneous contra-rotation in the comminuting chamber, and a plurality of said cutters carried by the shafts, at least one of the shafts having more than one said cutter secured thereon and the cutters of one shaft being interleaved with the cutter or cutters of the other, so as to co-operate in comminuting material fed into the chamber. The cutters to which the invention relates are of the kind comprising a generally disc-like body having at least one radially-projecting peripheral tooth provided with a cutting edge along a leading edge thereof, and the body defining a coaxial shaft aperture therethrough to accommodate a said shaft and defining a cutter axis. Such a cutter will be called a "cutter of the kind hereinbefore specified".
Although machines of the above kind are normally referred to as shredding machines or shredders, their comminuting action takes a form or forms which depend largely on the nature of the material being comminuted, and on the design of the cutters. The latter may in practice perform very little cutting as such; for example, glass will tend to be crushed into small pieces, whilst other common materials, such as thin metal, will tend to be torn and/or deformed by crushing. The material to be comminuted is most usually scrap or waste material, though shredders can be used to break up solid materials as part of, or in preparation for, industrial processes of various kinds.
Various types of shredding machine of the kind hereinbefore specified are in commercial use or have been proposed. British patent specification No. 1,315,347, for example, describes various forms of such a machine in all of which the single tooth of each cutter has a pronounced rake of at least 45.degree. and is undercut to give a cutting angle of not less than 45.degree., so that the tooth has a leading point at one end of its cutting edge whereby it performs a piercing action and then a cutting action. British patent specification No. 1,310,057 describes a shredding machine of the same general kind, but with cutters each of which co-operates with one cutter on the other shaft to comminute the material by at least partly working it between the single side face of one cutter of this pair and the single side face of the other, these faces being in a continuously overlapping relationship in the region in which comminution takes place. Our British patent specification No. 1,454,288 describes yet another machine characterised partly by the fact that each cutter has two profiled cutting edges extending around nearly the whole periphery of the cutter, one at each end of the cutter.
British patent specification No. 1,491,611 describes a shredder cutter which consists of several identical segments, rigidly bolted together to clamp them on to a cylindrical shaft to which the cutter segments are splined. The provision of a split or multi-segment cutter, which can be disassembled and then removed in a radial direction from the shaft, obviates a disadvantage of the one-piece cutters described in the other above-mentioned specifications, viz. that the cutters have to be threaded on and off the shaft, thus entailing the major operation of exposing one end of the shaft and then removing the cutters and other components (if any) between that end and the affected cutter.
In all of the above-mentioned specifications, the cutter is rigidly secured on the shaft. Indeed, it has hitherto been thought that it was always desirable to secure it as firmly as possible so that shaft and cutters behave at all times as a rigid unit, the cutting edge or edges being rigidly orientated with respect to the shaft. Thus, when the machine is subjected to so-called "crash-stop" conditions, e.g. when so-called tramp material in the form of an intractable object is encountered by the cutters
REFERENCES:
patent: 1249020 (1917-12-01), Bullock
patent: 1798000 (1931-03-01), Schultz
patent: 1884316 (1932-10-01), Smith
Hardwick John P.
Pezet Michael J.
Sarvestany Asadollah A.
Satharasinghe Dayananda
LandOfFree
Shredding machines does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Shredding machines, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shredding machines will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1915664