Technical Field
[0001] The present invention relates to a method of drying a tarpaulin - after cleaning
in a tarpaulin cleaning machine - in a drying tunnel, in which the tarpaulin transferred
therethrough is exposed to hot air. It also relates to a drying device at a tarpaulin
cleaning machine, having a drying tunnel, in which a tarpaulin transferred therethrough
is exposed to hot air, and a table, on which the tarpaulin is folded after having
left the drying tunnel.
Background of the Invention
[0002] An example of a tarpaulin cleaning machine is disclosed in
EP-B-1 247 889. In this machine, where water is used for washing, drying is performed in a drying
tunnel, through which the tarpaulin is transferred in a flat condition. Hot air is
used for the drying. By the term tarpaulin is throughout this document meant not only
a tarpaulin per se but any large piece of cloth, such as a tent cloth.
[0003] Under certain circumstances it has appeared that an improved drying is desired. A
requirement that 90-95 % of the humidity is removed from the tarpaulin can be difficult
to reach for all parts of the tarpaulin, especially for cord wetlings at side edges
of the tarpaulin.
The Invention
[0004] A required drying of a tarpaulin can according to the invention be attained in that
the tarpaulin is exposed to hot air not only in the drying tunnel but also after having
left it, the hot air in both cases being especially directed to areas for cord wetlings
on the tarpaulin.
[0005] A device for attaining the desired drying result has according to the invention means
at the drying tunnel as well as at the table for blowing hot air especially on portions
of the tarpaulin containing cord weltings.
[0006] Preferably, air inlet ducts are provided on the drying tunnel and air conduits are
provided at the table, both at locations for blowing hot air on portions of the tarpaulin
containing cord weltings.
[0007] The air inlet ducts as well as the air conduits may be connected to an air supply
tubing system, which contains at least one blower and at least one air heating battery.
[0008] The table preferably has an endless belt, which may be imparted a movement back and
forth for folding a tarpaulin leaving the drying tunnel and may transfer the folded
tarpaulin on the table to a drying station with the air conduits and further from
the table to a transport wagon or the like.
Brief Description of the Drawings
[0009] The invention will be described in further detail below under reference to the accompanying
drawings, in which
Fig 1 is an isometric view of a drying device according to the invention and
Fig 2 is a side view of the same device.
Description of Embodiments
[0010] A drying device according to the invention is intended to be a part of or be connected
to a tarpaulin cleaning machine, such as the one disclosed in
EP-B-1 247 889. In this machine the cleaned tarpaulin is fed by gravity through a drying channel,
where it is exposed to hot air supplied through tubes therein.
[0011] The drying effect obtained by this arrangement may be satisfactory in many instances,
but it has appeared that tarpaulins provided with corded weltings, i e weltings containing
cords, may not always be dried to a desirable degree. The purpose of the invention
is thus to improve the drying of tarpaulins in or for a tarpaulin cleaning machine,
especially if the tarpaulin has corded weltings.
[0012] A drying device for a tarpaulin cleaning machine is shown in Figs 1 and 2. The device
has a drying tunnel 1, through which a cleaned and comparatively wet tarpaulin 2 can
be fed by gravity. The drying tunnel 1 may have a width of more than 6 m in order
to accommodate for example one tarpaulin with a width of 5 m or two tarpaulins side
by side with a width of 3 m each. The length of the drying tunnel 1, which may be
mounted at an angle with the vertical as shown, may be some 3 m. The feeding speed
of the tarpaulin may be 3 m/min, which means that the tarpaulin 1 will be treated
for 1 min in the drying tunnel 1.
[0013] The drying tunnel 1 may have a bottom, on which the tarpaulin 2 moves, consisting
of longitudinally corrugated plastic panels for providing access of air to both sides
of the tarpaulin. Also the cover of the drying tunnel 1 may consist of longitudinally
corrugated plastic panels.
[0014] Air at a temperature of 60-90°C may be blown into the drying tunnel 1 in the movement
direction of the tarpaulin 2. For this purpose the drying tunnel 1 is provided with
a number of air inlet ducts 3. Such inlet ducts 3 may for example as shown be provided
at two levels of the drying tunnel 1, namely one not too far from the inlet to the
tunnel and another one towards its outlet. At each level, for example three inlet
ducts 3 may be provided, one centrally located and one towards each side edge of the
tunnel 1. The locations of the inlet ducts 3 are aimed at especially blowing the hot
air on the cord weltings of the tarpaulin or of the parallel tarpaulins, said weltings
being especially difficult to dry, as mentioned above. A requirement may be that after
the drying process the tarpaulin, including its cord weltings, must be 90 % or even
95 % dry.
[0015] The inlet ducts 3 are to be connected to an air supply tubing system 4. Only certain
portions of this system 4 are depicted, but it contains one or more blowers and one
or more air heating batteries for the supply of hot air at a desirable volume and
speed.
[0016] The tarpaulin 2 leaving the drying tunnel 1 is to be folded on a table 5. This table
preferably has a width corresponding to that of the drying tunnel and is provided
with an endless belt 6 for transferring the tarpaulin 2 in relation to the drying
tunnel 1. In a first stage the endless belt 6 is imparted a movement back and forth
during the feeding out of the tarpaulin from the drying tunnel 1, so that the tarpaulin
2 is nicely folded on the table 5. In a second stage the endless belt 6 moves forward
(to the left in the drawings), so that the tarpaulin 2 arrives in a drying station
on the table. In a third stage the endless belt 6 moves further forward for unloading
the now dried tarpaulin on a transport wagon 7 or the like.
[0017] In the drying station mentioned at the second stage above, hot air from the air supply
tubing system 4 is supplied to the tarpaulin 2 lying folded on the transport belt
6 through fixed air conduits 8. As shown, air conduits 8, connected to the air supply
tubing system 4, may be provided centrally over the tarpaulin 2 as well as at each
side edge, i e where there may be cord weltings on the tarpaulin.
[0018] Modifications are possible within the scope of the appended claims. It is especially
to be noted that the drying device according to the invention can be used in conjunction
with other machines than a tarpaulin cleaning machine of the kind disclosed in
EP-B-1 247 889.
1. A method of drying a tarpaulin (2) - after cleaning in a tarpaulin cleaning machine
- in a drying tunnel (1), in which the tarpaulin transferred therethrough is exposed
to hot air, characterized in that the tarpaulin (2) is exposed to hot air not only in the drying tunnel (1) but also
after having left it, the hot air in both cases being especially directed to areas
for cord wetlings on the tarpaulin.
2. A drying device at a tarpaulin cleaning machine, having a drying tunnel (1), in which
a tarpaulin (2) transferred therethrough is exposed to hot air, and a table (5), on
which the tarpaulin is folded after having left the drying tunnel, characterized by means (3, 8) at the drying tunnel (2) as well as at the table (5) for blowing hot
air especially on portions of the tarpaulin containing cord weltings.
3. A drying device according to claim 2, wherein air inlet ducts (3) are provided on
the drying tunnel (1) and that air conduits (8) are provided at the table (5), both
at locations for blowing hot air on portions of the tarpaulin (2) containing cord
weltings.
4. A drying device according to claim 3, wherein the air inlet ducts (3) and the air
conduits (8) are connected to an air supply tubing system (4).
5. A drying device according to claim 4, wherein the air supply tubing system (4) contains
at least one blower and at least one air heating battery.
6. A drying device according to claim 3, wherein the table (5) has an endless belt (6),
which may be imparted a movement back and forth for folding a tarpaulin (2) leaving
the drying tunnel (1) and may transfer the folded tarpaulin on the table to a drying
station with the air conduits (8) and further from the table to a transport wagon
(7) or the like.