Note: Descriptions are shown in the official language in which they were submitted.
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1 "HEATING SYSTEM FOR OUTDOOR CONVEYORS IN A CARWASH"
2
3 FIELD OF THE INVENTION
4 Embodiments of the invention related to systems for heating
surfaces and more specifically to heating the sliding surfaces of a carwash
6 conveyor in a wet and potentially freezing environment.
7
8 BACKGROUND OF THE INVENTION
9 It is known to provide one or more conveyors for movement of
objects from one place to another. There are many different types and
11 configurations of conveyors which have been known for decades. The
conveyors
12 may be a single endless belt type conveyors or side by side synchronous
13 endless belts which engage the object at opposing points or in some cases
are
14 synchronous sections of conveyors, single or dual belt type, which feed
from one
to another.
16 Conveyors are used in a wide variety of contexts including, but not
17 limited to, manufacturing, transport and loading of objects. In most cases,
18 conventional conveyors operate indoors in a relatively controlled
environment
19 and thus are not exposed to ambient temperatures which may be below
freezing
temperatures in combination with high levels of moisture.
21 In the case of a carwash, it is known to provide means for moving a
22 vehicle through a wash tunnel. Typically, the vehicle enters an entrance of
the
23 tunnel where the vehicle is engaged by a below ground conveyor and guide
24 track having means for engaging at least a single wheel of the vehicle, the
vehicle being advanced through the wash by the conveyor, the entirety of the
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1 conveying system being enclosed in the wash tunnel where water used to wash
2 the vehicles and heated air prevents the conveying mechanism from freezing
3 during the winter.
4 US Patent 1,484,071 to Memmen teaches a dual belt conveyor for
forming runways for the wheels of an automobile to be washed. The conveyor
6 assists in lowering the vehicle into a tank or vat and further assists in
agitating
7 the water to wash the undercarriage as the endless belts of the conveyors
and
8 the wheels of the vehicle are caused to move.
9 Recently, published US patent application 200601918773 to Horn
describes one or more conventional dual-synchronous belt type conveyors for
11 use in a carwash. The conveyors each have a pair of spaced apart belts such
as
12 is well know in the art and the belts support the wheels of the vehicle. A
first
13 conveyor is stopped to accept the vehicle and can be sped up to a speed
14 synchronous with the main conveyor which, when the vehicle is transferred
from
the first conveyor to the main conveyor, moves the vehicle through the wash
16 tunnel. Synchronizing of conveyor belts, single or dual belt types, is well
known
17 in a variety of industries. Horn is silent regarding use of the conveyors
outside
18 the carwash and at low ambient temperatures.
19 Ideally, in order to fully automate a carwash system and to ensure
correct positioning of the vehicle on the conveyor at the entrance, in the
tunnel
21 and possible at the exit, conveyor systems capable of being exposed to the
22 environment outside the wash tunnel while maintaining operability in very
low
23 ambient temperatures are desired.
24
2
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I BRIEF DESCRIPTION OF THE DRAWINGS
2 Figure 1 is a plan view of a conveyor system according to an
3 embodiment of the invention and having an entrance conveyor positioned
4 outside the entrance to a wash tunnel and optionaily having an exit conveyor
positioned at the exit and outside the wash tunnel, the conveyor system
6 incorporating heated concrete pads at the entrance and optional exit
conveyors;
7 Figure 2 is a plan view of the entrance conveyor according to Fig.
8 1;
9 Figures 3a and 3b are partial longitudinal sectional views according
to Fig. 1;
11 Figure 4 is a cross-sectional schematic view of a heated concrete
12 slab and a conveyor belt installed thereabout;
13 Figure 5 is a perspective view of a frame and heating system
14 according to an embodiment of the invention;
Figure 6 is a plan view of a frame and heating system for a heated
16 concrete slab for use according to Fig. 4;
17 Figure 7a is a perspective view according to Fig. 5;
18 Figure 7b is and end view according to Fig. 5;
19 Figure 7c is a sectional view along section lines C-C according to
Fig. 6b;
21 Figure 8 is a detailed partial sectional view of a connection to a
22 fluid supply in an embodiment of the heated slab using a hydronic heating
23 system;
24 Figure 9 is a plan view of an electric heating system according to
an embodiment of the invention.
3
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1 Figure 10 is a photograph of concrete being added to the frame
2 and tubing as shown in Fig. 6 for forming the heated slabs;
3 Figure 11 is a photograph of a plurality of heated slabs installed for
4 use under an entrance conveyor of a carwash according to an embodiment of
the invention; and
6 Figures 12-21 illustrate details of a support system for suspending
7 he heated and non-heated concrete slabs and gratings over the floor of the
8 trench.
9
4
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1 SUMMARY OF THE INVENTION
2 Embodiments of the invention disclosed herein utilize a conveyor
3 for moving a vehicle through a carwash tunnel. The use of the term
"conveyor" is
4 intended to describe any suitable type conveyance system for moving the
vehicles therethrough and is not intended to be limited only to the embodiment
of
6 conveyor discussed herein.
7 Embodiments of the invention teach a carwash for use in all
8 seasons and particularly suited for installation in cold weather climates
wherein
9 the carwash provides at least one conveyance system which extends outside a
wash tunnel for loading vehicles outside the wash tunnel, the conveyance
11 system being heated for preventing freezing in extreme cold weather
conditions.
12 More particularly embodiments of the invention teach a heating
13 system for a carwash conveyance system comprising a plurality of heated
14 concrete slabs which are installed in proximity to the conveyance system
for
preventing freezing during extreme cold weather conditions.
16 As shown in Fig. 1 and in an embodiment of the invention, a
17 carwash 1 comprises a wash tunnel 2 having at least one conveyance system 3
18 extending through the wash tunnel 2 and outside the wash tunnel 2 at an
19 entrance 4 for loading vehicles outside the wash tunnel 2. More preferably,
the
car wash I comprises a main endless belt conveyor 5 installed therein and at
21 least one additional conveyor 6 which is at least partially exposed to the
22 environment outside the wash tunnel 2. One form of endless belt conveyor is
the
23 dual belt conveyor taught by SafeTveyr in US published application
24 200601918773.
5
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1 In the embodiment shown, the additional conveyor 6 is an entrance
2 conveyor 6 which extends outwardly from the wash tunnel entrance 4, a first
end
3 7 being adjacent to the main conveyor 5 and a second end 8 being outside the
4 entrance 4 to a carwash tunnel 2. At least a portion of the entrance
conveyor 6 is
fully exposed to the elements. The entrance conveyor 6 operates to load a
6 vehicle and transfer the vehicle to the main conveyor 5. The entrance
conveyor 5
7 is stopped at the time of loading and a vehicle is driven onto the entrance
8 conveyor 6 and placed in park. Once the vehicle is positioned on the
entrance
9 conveyor 6, the entrance conveyor 6 is operated to achieve a speed
synchronous with the speed of the inside main conveyor 5 and the vehicle is
11 transferred to the inside main conveyor 5 for washing inside the wash
tunnel 2.
12 Optionally, a third endless belt conveyor or exit conveyor 9 is
13 positioned at an exit 10 end of the main conveyor 5 and at least a portion
of the
14 exit conveyor 9 extends outside the wash tunnel 2 at an exit 11 from the
wash
tunnel 2. When the wash cycle is completed, the vehicle is transferred from
the
16 main conveyor 5 to the exit conveyor 9, at synchronized speed. The exit
17 conveyor 9 is caused to come to a stop and the vehicle can be driven off.
18 In one embodiment, and to install at least the main conveyor 5, the
19 entrance conveyor 6 and the optional exit conveyor 9, a trench 12 (Figs. 3a
and
3b) extends through the wash tunnel 2 and outside therefrom. The conveyors 5,
21 6 and 9 are installed inside the trench 12 using support legs 13 and a grid
22 structure 14, which elevates the conveyors 5,6,9 sufficiently above a floor
15 of
23 the trench 12 to permit operation of endless belts 16 of the conveyors
5,6,9. As
24 shown in Fig. 4, structural pads or slabs 20, typically concrete, are
installed
between upper and lower portions 21,22 of the endless belts 16, the upper
6
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1 portion 21 operating in sliding contact with an upper surface 23 of the
structural
2 pads 20 when a vehicle is loaded on the conveyors 5,6,9. Steel plates may be
3 used on the top surface of the slabs to reduce friction between the upper
portion
4 21 and the slabs 20. Further, water is typically sprayed between the upper
surface 23 of the slabs 20 or the steel plates and conveyor belts 21,22 to
ensure
6 adequate lubrication therebetween.
7 Details of an embodiment of a supporting structure for the concrete
8 slabs 20, heated 25 and not heated are shown in Fig, 12-21. In one
embodiment,
9 as shown in Figs. 3a and 3b, the floor 15 of the trench 12 is slanted so as
to
cause liquids therein to flow to a drain or plurality of drains, typically
located
11 inside the wash tunnel 2. In one embodiment the floor of the trench is
slanted
12 about 0.02m/m.
13 Having reference to Figs. 1-11, and in the case of the entrance
14 conveyor 6, the entrance conveyor 6 is installed in a portion 24 of the
trench 12
which extends outwards from the wash tunnel entrance 4. Structural slabs 25,
16 similar to those used in the wash tunnel 2, are provided with heating means
26
17 to prevent water, snow and the like from freezing and hindering operation
of the
18 entrance conveyor 6. The heated slabs 25 are similarly supported over the
floor
19 15 of the entrance trench 12 and between the upper and lower portions 21,22
of
the endless belts 16 of the entrance conveyor 6. In one embodiment, the heated
21 slabs 25 are suspended using a plurality of support members extending
between
22 the slabs 25 and the trench 12. Other such suitable support members which
23 engage and suspend the slabs 25 may be used.
24 Similarly, the optional exit conveyor 9, which may be installed in a
portion 27 of the trench 12 extending outwardly from the exit 11 of the wash
7
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1 tunnel 2, is also freeze-protected using heated concrete slabs 25 which are
2 installed in the trench 12 as for the entrance conveyor 6.
3 In one embodiment, best seen in Figs. 1 and 2, additional heated
4 concrete slabs 25 are installed inside the wash tunnel 2 adjacent the
entrance 4
and the exit 11 and contiguous with the entrance and exit conveyors 6.9 to
6 ensure the conveyors 6,9 are protected from freezing inside the wash tunnel
2
7 when exposed to freezing temperatures adjacent the entrance and the exit
4,11
8 of the wash tunnel 2. In this embodiment, motors and apparatus used to drive
9 the entrance conveyor 5 and the main conveyor 6 are typically positioned
within
the wash tunnel 2 adjacent the entrance and exit 4,11 of the wash tunnel 2 to
11 limit exposure to extreme ambient temperatures.
12 Having reference to Figs. 5-8 and Figs. 10-11, and in one
13 embodiment, a hydronic system 30 is used as the means for heating the
heated
14 concrete slabs 25. The heated concrete slabs 25 comprise a frame 31 in
which a
support grid 32 is formed. In one embodiment, the frame 31 comprises end and
16 side channels 33,34, inside which a grid structure 35 of transverse and
17 longitudinal members 36,37 is supported. In one embodiment the longitudinal
18 members 37 are epoxy rebar and the transverse members 36 are stainless
steel
19 rebar. Loops of tubing 38, such as'/2' cross-linked polyethylene tubing
(PEX), for
example AQUAPEX available from Wirsbo Company of 4925 W 148th Street,
21 Apple Valley MN, 55124, USA, are laid in the frame 31 and supported by the
grid
22 structure 35. Alternately, the loops 38 can be formed using fittings 39
such as
23 tees and elbows to create a fluidly connected grid of tubing in the frame
31. An
24 inlet 40 and an outlet 41 are connected to opposing ends of the fluidly
connected
8
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1 tubing 38 and are supported in the frame 31. Concrete is poured into the
frame
2 31 and is allowed to set.
3 In one embodiment, the heated concrete slabs 25 are about 4
4 inches thick. The hydronic tubing 38 is positioned at about 1%2 inches from
the
surface 23 of the slab 25 and the tubing 38 is tied to the grid structure 35
using
6 plastic wire ties. The concrete used is 35 MPa Class Cl with 3/8" aggregate
mix
7 designed to withstand both high and low temperatures and chloride attack
from
8 commonly used deicing chemicals. In this embodiment, the hydronic tubing 38
is
9 installed in a reverse-return loop system so as to obtain an even
distribution of
heat over substantially the entire surface of the heated concrete slab 25.
11 Once installed, best seen in Fig. 2, the inlets 40 of the heated
12 concrete slabs 25 are connected to a supply of heated fluid, such as hot
water or
13 glycol. The outlets 41 are connected to a return line which returns the
fluid to the
14 heater system for repeated recycling through the heated slabs 25. In one
embodiment, each of the outlets 41 are fit with an air vent 43 used to bleed
air
16 out of the tubing lines 38 when the fluid, such as glycol, is introduced.
17 Heat from the fluid flowing through the tubes 38 is transferred to
18 the concrete, a thermally conductive material, which acts as a thermal mass
to
19 radiate heat for preventing freezing of water between the heated slabs 25,
the
conveyor belts 16 and in the area of the trench 12.
21 In one embodiment, as shown in Fig. 9, the means for heating the
22 concrete slabs 25 is an electric heating system 50. A heating pad or mat 51
of
23 heating wire is embedded in the heated concrete slab 25 and is connected to
a
24 240 V supply. One such heating system is the Easy-Heat Sno"Melter Mat
#GO10X36-240-50 series available from Easy Heat Inc. of 20 East New Carlisle,
9
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1 Indiana, 46552, USA. The mat 51 is fit to the dimensions of the slab 25, is
placed
2 in the frame 31 and tied to the grid structure 35 after which the concrete
is
3 poured into the frame 31, embedding the mat 51 in the concrete. A hot-cold
joint
4 52 is installed between a heating lead 53 and a cold lead 54 connected to
the
mat 51. The cold lead 54 extends through a fiberglass composite conduit 55 and
6 extends about 6 inches beyond the slab 25 for connection to the electrical
7 supply. One suitable fiberglass composite conduit 55 is a 1/2 inch diameter
8 conduit available from Fre Composites, 75 Wales Street, St. Andre-
d'Argenteuil,
9 Quebec, Canada.
