Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
The present invention relates to apparatus for cutting
continuous elongated material, such as ~ilamentary material, into
predetermined shorter lengths.
Such apparatus when used to cut fibres, is commonly
termed a staple cutter and one such known form of commercially
used staple cutter is disclosed in British Patent Specification
No. 1,204,363 (Eastman Kodak Company). This apparatus comprises
a cutting assembly in the form of a wheel having a number of
spaced apart knives located in the region of its periphery,
the knife edges~projecting radially outwardly with respect to
the wheel. In use, the wheel is rotated by a motor and a tow
of the fibres to be cut is wound around the wheel on top of the
knife edges. When a number of layers have been wound onto the
wheel a pressure wheel engages the outermost layer thus pressing
the innermost layer against the knife edges and cutting the
fibres in this layer. The cut fibres pass between the knives
inwardly of the wheel and are conveyed away from the central
region of the wheel to a storage zone, preferably by the use of
air currents, The main use of such apparatus is in the cutting 20 of crimped fibres, the fibres passing from a crimping machine
to the apparatus and being tensioned as they are wound onto the
cutter wheel, so that the crimp is removed or virtually removed
; be~ore the fibres are cut. As soon as the fibres are cut the
i crimp reduces the length of the cut fibres, :Eacilitating the
passage of the fibres between the knives.
Such known staple cutters cut a number of fibres at any
' one time and operate at a relatively slow peripheral speed,
" ~urther, if such a staple cutter is used to cut uncrimped fibre
i.e. flock, there is a tendency for the spaces between adjacent
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- knives to become clogged, requiring the cutting assembly to be
stopped and cleared.
An aim of the presen~ invention is to provide a staple
cutter which can operate at considerably ~igher peripheral speeds
than the above described known form of staple cutter and is able
to produce floc without clogging.
According to the present invention there is provided
an apparatus for cutting elongate material into predetermined
lengths comprising a spool body around which the elongate
material can be~wound to provide a layer of elongate material,
an annular member located around the spool body and arranged to
` perform a pivotal motion, whereby radialiy inwardly directed
fingers of the annular member, which fingers engage in slots
- which extend axially in the spool body, advance the layer of
elongate material along the spool body as it is wound onto the
spool body, and at least one cutter provided in the path of the
advancing layer.
In the preferred embodiment of the present invention
the spool body is a cylindrical member~ a winding assembly
being arranged to rotate around the spool body to deposit a
single layer of fibre i.e. elongate material, on the spool body.
In an alternative embodiment the spool body may be rotatable
relative to the winding assembly. Further, the spool body may
alternatively have a square or rectanguIar transverse cross-
section, or any other desired transverse cross-section.
In the preferred embodiment of the present invention
the means for advancing the layer of fibre take the form of an
annular member which has radially inwardly directed fingers which
engage in slots in the spool body, the slots extending axially
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of the spool body. The annular member is arranged to execute
a pivotal movement as the winding assembly moves around the
spool body, thus moving the fibres along the spool body
- towards spaced apart cutters provided on the spool body.
The number and spacing of the cutters depends upon the
desired length of the staple to be cut and preferably the cutters
are arranged so thàt the fibre layer is advanced into a V-shaped
groove defined on one-side by the spool body and on the other
side by the cutting edges of the cutters. Alternatively the
cutters may be arranged with their cutting edges angled away
from the spool body in the direction of advancing movement of
the ibre layer. If desired the cutters may be arranged to
execute a reciprocating motion to aid cutting of the tow or
single filament.
To retain the fibre wound onto the spool body, as a
single layer, and to retain the fibre as it is being cut, retain-
ing means are preferably provided and may take the form of a
housing which can be fixed wi~h respect to the spool body, the
housing being dimensioned to leave only a small, gap i.e. equi-
` valent to one fibre layer between the spool body and the housing.
The whole apparatus is preferably located within anouter housing and the cut fibres can be entrained towards a
collectionzone by air currents. Further, to drive the winding
assembly or the spool body, dependent upon the embodiment under
consi~leration, a torque motor may be used to advantage to main-
taln a substantia~ly constant tension for the fibre wound onto
the spool body.
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The apparatus of the present invention may satisfactor-
ily be operated to cut a single fibre, crimped or not, at speeds
considerably in excess of the operational speed of the above
described kno~n staple cu~ter. The operational speeds of
- apparatus according to the present invention may be of the order
of 4000 to 6000 revolutions~minute. Slower speeds may be
selected if cu~ting a tow of fibres.
The present invention will now be further described,
by way of example, with reference to the accompanying drawing,
in which -`
Figure 1 shows a cross-sectional vlew of an embodiment
of the present invention.
In the accompanying drawing one embodiment of apparatus
according to the present invention is illustrated. This apparatus
includes an elongate spool body 1 of circular cross-section which
is fixedly mounted within a stationary housing body 2, the housing
body 2 having an extension 3 part ~ of which is located over the
end 5 of spool body 1 to form retaining means which, when the
apparatus is in use, retains a layer of fibre on the spool body.
Cutter blades 6 are mounted on the end 5 of spool body 1 with
-their cutting edges lying in planes which include the longitudinal
axis of spool body l. Mounted for rotation about the spool body
~,~ in the space between the housing body and the spool body, is a
winding assembly in the form of a cylindrical member 7 which in-
cludes a guideway 8 for the fibre to be cut. The plane of the
end 9 o~ the cylindrical member 8 is angled to the longitudinal
.is o~ the cylindrical member 8 and carries a bearing 10 which
s~lpports aduancing means in the form of an annular member 11.
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The annular member 11 has radially inwardly extending fingers
12 which engage in slots 13 in the spool body 1, the slots 13
extending axially of the spool body.
In use, the fibre is passed along guideway 8 and wound
around the spool body 1 in region 14 thereof. The cylindrical
member 7 is then rotated drawing further fibre along guideway 8
and winding it onto the spool body 1. As the cylindrical member
7 rotates relative to the spool body 1, so the annular member 11
pivots causing the layer of fibres on the spool body 1 to be ad-
vanced towards the cutters 6. Continued operation causes the
fibre to be pressed against the cutters 6 and to be cut, the
number and spacing of the cutters 6 determining the'length of
the cut fibres and the part 4 of extension 3 maintaining the
single layer configuration of fibres on the spool body 1. The
cut fibres are then entrained away, preferably by air currents,
to a collection zone.
The cylindrical member 7 is driven by a motor (not
shown) whlch is geared to edge 15 of the cylindrical member.
Alternatively, part 16 of the spool body and the cylindrical
member 7, can be constructed as the stator and rotor of an
electric motor. Preferably, the cylindrical member 7 is driven
by or forms part of a torque motor9 this being advantageous as
it will maintain a substantially constant tension for the fibre
as it is wound onto the spool body at a constant rate.
A possible modification within the scope of the present
invention is the provision of the cutters on the inside surface
oE part ~ of extension 3 in Fig. 1. In this case the cutters
preferably extend into mating slots in the surface of the spool
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body.
It is envisaged that the spool body 1 or the part 4
may be replaced i.e. to change the cutter spacing, to enable
` different length fibres to be produced. Further, as the cutters
are preferably parallel to each other there is no danger of
clogging when floc is produced.
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