Web crushing arrangement for a card web

Textiles: fiber preparation – Working – Crush rolls

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

19106R, 29116AD, D01G 1596

Patent

active

043522238

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The present invention relates to a web crushing arrangement for a card web having cooperating working rolls, with a support member extending along one of the rolls for taking up the pressing surface, which is pressable against the roll by pressure bodies, as used in staple fibre spinning, and more particularly, in processing natural fibres.
Crushing a very thin fibre web, such as it is taken off from the doffer cylinder of a card, has as its purpose reducing the impurities, mainly the harder seed particles, by crushing them in such a manner that they impair the subsequent processing stages to a lesser degree. They also can be eliminated from the fibre material more easily.
For achieving good results using a web crushing arrangement of this type, the uniformity of the crushing pressure generated along the full working width of the roll, which is of the order of about 1 m, is of decisive importance. If the pressure is too low, the impurities are not crushed, or are not crushed sufficiently, i.e. the crush roll arrangement does not achieve the desired effect; whereas too high pressures result in damage to the fibre material. For evenly loading the crush rolls many efforts have been undertaken already; however, these have resulted in proposed solutions which are still unsatisfactory.
According to a known web crushing arrangement of the aforementioned type (German Patent PS 904'150), a uniform pressure distribution with two working rolls supported along their length is achieved by each working roll being supported on its working surface by at least one pressure-loadable support member; the support member preferentially being designed as a member of uniform stiffness.
In a further development of this solution (German Patent PS 918'676), design of the pressure transmitting element arranged between the working roll and the support member as an elastic element is also known.
The disadvantage of this crush roll arrangement is that the rotating crush roll, with its cylindrical surface, is in frictional contact with the pressure loaded support member, or with the pressure transmitting element, respectively, under the full pressure force. This causes a corresponding energy loss and presents considerable danger of damage, or of excessive wear, respectively, to the very susceptible roll surface, which, in turn, causes increased danger of lap-up formation on the working roll.
Also, maintenance and operating work on such web crushing arrangements are increased due to excessive danger of lap-formation.


SUMMARY AND OBJECTS OF THE INVENTION

It thus is an object of the present invention to propose a web crushing arrangement, which overcomes the abovementioned disadvantages of the known arrangement, and which permits generation of a uniform and easily adjustable pressure over the full width of the rolls. In particular, the proposed arrangement also eliminates any danger of lap-up formation on the working rolls and thus is provides high reliability.
This and other objects are achieved by a web crushing arrangement for a card web of the type mentioned initially by an arrangement supplying compressed air to the facing complementary pressing surface. The compressed air emerging from the compressed air supply arrangement forms an airfilm between the pressing surface and the roll, which transmits the load from the pressing surface to the roll.
In a preferred embodiment of the invention, the pressing surface is formed by a substantially rigid pressing slat, which is guided to be radially movable with respect to the surface of the working roll in the support member. The pressing slat is pressed aginst the working roll by elastic loading means.
In a further embodiment of the invention the elastic loading means are formed by a plurality of pressure springs, whereas in a further alternative design example, they consist of a pressurized chamber, known as such, arranged between the support member and the pressing slat.
According to an alternative design example the pressurized chamber is connected via bores,

REFERENCES:
patent: 3310244 (1967-03-01), Ramo
patent: 3802044 (1974-04-01), Spillmann et al.
patent: 4091517 (1978-05-01), Lehmann et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Web crushing arrangement for a card web does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Web crushing arrangement for a card web, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Web crushing arrangement for a card web will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-418546

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.