Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1312474
Sheath for use in the drying of s~ins.
The invention relates to a sheath or covering
case to be applied in the type of s~in dryins, where
the fresh s~ins or furs are arranged on a generally
slightly tapered board fitting to the actual skins and
adapted to pass through channels and cut-outs provided
therein a supplied conditioned air current into contact
with the inside of the s~ins, the sheath having the
form of an elongated bag made from a fat absorbing,
air-permeable material.
Such sheaths fulfill various purposes, firstly,
because they protect the board against dirt from the
inside of the individual s~ins and, secondly, because
they contribute to drying the s~in by absorbing its
fat.
Prior sheaths are made from comparatively coarse
paper and are most frequently shaped as slightly coni-
cal tubes surrounding the central portion of the board
but not the extreme portion thereof. Said design is an
indispensable consequence of the fact that paper having
the necessary strength and absobing properties is not
porous or air-permeable to such a degree that the air
current supplied through the board can penetrate the
sheath and get into contact with the inside of the
skin. The cover should therefore be made shorter than
the board proper with a view to laying bare some of the
vent holes of the board. Air is then flown between the
inside of the s~in and the outer surface of the sheath.
In order to provide reasonable venting conditions,
prior sheaths typically terminate on the level of the
tail head of the mounted s~in, meaning that in order to
protect also the part of the board located opposite the
ripped-up tail it is necessary to apply at this place a
' separate piece of "tail paper". Said piece of paper has
to be ~astened separately, thereby impeding and pro-
tracting the mounting procedure.
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As mentioned above, one of the purposes of the
sheath is to protect the board against getting smudged
by flesh remains, blood etc. from the inside of the
s~in. The necessary baring of the board counteracts
said aim, and such baring actually causes direct con-
tact between the inside of the s~in and the board. This
means, on one hand, that the board gets smudged and, on
the other hand, that it is necessary to clean the board
after every use and this is both time consuming and
more expensive.
In order to solve the problem with respect to
the incomplete wrapping it is an object of internation-
al patent application No. PCT/FI85~00049 (publiqhed
patent specification No. W086~00091) to provide a pro-
tecting bag fitting to the drying board or shapingitself therearound. This prior bag consists of two
strips of paper glued together at its longitudinal
sides by adhesive seam.s. With respect to the adaptation
to the tapered end of the drying board the bag is
further provided either with a number of secondary
adhesive seams parallel to the long sides and which on
inserting the drying board are over a length indivi-
dually torn, corresponding to the edges of the tapered
end or with an adhesive seam substantially similar to
the tapered end.
Besides the productional complications impli-
cated by providing secondary or shape-adapted adhesive
seams, it is a drawbac~ of this design that there are
flaps around the tapered end of the drying board which
due to the natural stiffness of the paper have to be
bent in over the tapered end prior to pulling the un-
processed s~in on to the drying board. In this case
where the fittiny to the drying board is effected by
tearing parallel secondary adhesive seams, difficulties
in pulling off the bag will moreover often occur
because the bag partially adheres to the board due to
adhesive remains thereon.
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According to the above suggested design of bag
t is possible to provide single-bags by unwinding from
a roller on which bags of the same length and having
the mentioned adhesive seams are separated by trans-
verse perforations.
Inspite of the possibility of adaptat~on aimedat, the above outlined design of the bag does not glve
a solution to another drawback of known sheaths con-
sisting in that the sheaths are not resilient or
flexible and therefore cannot easily be adapted to dif-
ferent board si~es, i.e. such boards used for example
for s~ins from male and female min~s. It is therefore
necessary to purchase and stoc~ as many sizes of
sheaths as there are sizes of boards, and every time a
sheath shall be pulled on to a board it must be ensured
to choose the correct size of sheath.
The sheath according to the invention differs
from prior art sheaths in that the sheath is designed
as a hose of uniform width and made from a soft cling-
able, resilient material of substantially homogenousair--permeability and having a certain natural resi-
liency, e.g. non-woven fibres of polypropylene.
Analogous to the above suggested design it is
obtained that the sheath is capable of covering the
entire board, due to the fact that the sheath is air-
permeable per se, thereby protecting the board against
getting ~mudged and ma~ing any cleaning of the board
superfluous after use or at least reducing the
necessity of a possible cleaning. As the sheath is
actually now in contact with the entire inside of the
s~in an efficient absorption of fat from the s~in is
concurrently obtained. Moreover, a favourable con-
sequence is that it also becomes much easier to pull
off the s~in from the board after completed drying
because the s~in is not in a position to adhere ~irmly
to the board. By virtue of the homogeneous air-perme-
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ability of the sheath and unlike the type of paper material
used in conventional sheaths as well as for the above
suggested design, an improved air dispersion during the
drying process is moreover obtained and thus a more uniform
drying of the skins. However, the present invention
entails particularly the advantage that within certain
limits it is possible to make use of sheaths of only one
size since the clingable, resilient and flexible sheath
easily adapts to boards of varying sizes. If the width of
the board is a little larger than the width of the sheath
in its flaccid condition, the sheath enlarges a little
while, conversely, the bag-shaped sheath forms soft folds
around the board, thereby clinging closely thereto.
The clingability and the resiliency of the sheath and
its hose-like form of a uniform width there is obtained the
additional advantage of rationalization that the sheaths
may be offered as "endless" hoses on rollers instead of
either as individual sheaths or on rollers with
perforations for tearing off at predetermined lengths.
In an embodiment of the sheath according to the
invention single sheaths are thus obtained by cutting from
a hose roller at a desired length, following which the cut-
off length is closed by transverse sealing at one end. In
use a suitable length of hose is unwound which is then cut
off and sealed, following which it is ready for use. The
closing and cutting-off may be effected in any suitable
manner, and e.g. tape, staples or hot welding may be used
for the sealing.
In a broad aspect, therefore, the present invention
relates to a method of drying skins by mounting a fresh
skin on a tapered board having gas-distribution means
therein and covered by a sheath of fat-absorbing, gas-
permeable material in the form of an elongate bag and
passing a conditioned gas current through said means to
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contact the inside of the skin, wherein the sheath is of
uniform width, is made from a soft, clingable, resilient
material of substantially homogenous gas-permeability and
covers the entire length of the board.
In another broad aspect, the present invention relates
to a skin-drying board comprising a tapered board having
gas-distribution means therein and covered by a sheath of
fat-absorbing air permeable material in the form of an
elongate bag, wherein the sheath is of uniform width, is
made from a soft, clingable, resilient material of
substantially homogenous gas-permeability and covers the
entire length of the board.
The invention will now be explained in more detail
with reference to the somewhat schematical drawing
illustrating a board on which a sheath according to the
invention is mounted and a skin, but for the sake of
clarity the skin is not shown on the right half of the
drawing.
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As it will appear a skin 1 to be dried is
pulled on to a slightly wedge-shaped or tapered board
2 which, prior to arranging the skin on it, is at
first covered with an elongated sheath 3 according to
the invention. Board 2 made from wood has a central,
continuous slit or slot 4 which from a point close to
the tapered end of the board extends substantially
throughout the length of the skin. Sllt 4 is in com-
munication with approximately semi-c~rcular notches or
cut-outs 5 provided in the narrow lateral edges of
the board and extending parallel to the plane of the
board. The air current is supplied as illustrated by
the arrow 6 through a central tube 7 inserted
through the mouth opening of the s~in and the sheath
and discharges opposite slit 4. The air will then be
dispersed along the board through cut-outs 5 and slit
4 proper.
Sheath 3 having the form of an elongated
bag or soc~ is pulled in over the narrow end of the
board and fastened after stretching close to the wide
end of the board by means of pins 8 or in any other
advantageous way. The -sheath is made from non-woven
fibres of polypropylene and by virtue of its natural
resiliency it is adaptable to the size of the actual
board.
For the sake of clarity the skin is illustrated
on the drawing as fittir,g loosely around the board. In
practice, the s~in fits, however, tightly to board 2
and sheath 3 ir. order to obtain, on one hand, the
contact with the inside of the skin that is necessary
, for the sheath to effect the fat absorption and, on the
other hand, because board 2 is intended to serve as
stretching board. S~in 1 is in a conventional manner,
not shown, secured to board 2.
; 35 The sheath according to the invention does not
need to be ~ade from non-~oven fibres of polypropylene,
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other materials having similar properties, such as air-
permeability, clingable resiliency and natural st1ff
ness, being applicable as well.
