FIELD OF THE INVENTION
[0001] The present invention relates to a coating machine and a coating method thereof.
More particularly, the invention relates to a coating machine and method for use in
the manufacture of cardboard boxes to coat heat-insulating cardboard with wax.
BACKGROUND OF THE INVENTION
[0002] Nowadays, marine products such as seafood are typically transported in cardboard
boxes. As liquids are sure to be found on the surface of seafood, it is required that
cardboard boxes for storing marine products be water-resistant to some extent so that
boxed marine products can be transported over long distances.
[0003] To waterproof a cardboard box, it is common practice to coat each of its cardboard
components with liquid wax, which forms a wax layer capable of isolating the surface
liquids of marine products from the cardboard itself. However, the existing coating
machines can effectively coat only the surface, but not the edges, of cardboard with
wax. The resulting cardboard boxes, therefore, are flawed in that they are permeable
to water and hence prone to break when wet.
[0004] To overcome the foregoing drawback, a novel coating machine for forming a wax layer
on cardboard is needed.
BRIEF SUMMARY OF THE INVENTION
[0005] One objective of the present invention is to provide a coating machine that is structurally
simple, highly automated, and capable of waxing not only the surface, but also the
edges, of cardboard so that waterproofness of the entire cardboard is ensured.
[0006] Another objective of the present invention is to provide a coating method that is
easy to perform, highly automated, and capable of waxing not only the surface, but
also the edges, of cardboard so that waterproofness of the entire cardboard is ensured.
[0007] The above objectives can be achieved by the following technical solutions:
[0008] The present invention provides a coating machine that includes a cardboard conveying
mechanism and a wax dispenser.
[0009] The cardboard conveying mechanism has a front end and a back end, wherein the front
end is lower than the back end.
[0010] The wax dispenser is provided above the back end and is provided with a wax dispensing
roller on each of two lateral sides of the wax dispenser.
[0011] Preferably, each of the wax dispensing rollers includes a roller body and a felt
sleeve.
[0012] Each roller body has a hollow chamber in communication with the wax dispenser through
a connecting tube and is provided with a plurality of through holes in communication
with the hollow chamber.
[0013] Each felt sleeve is mounted around the corresponding roller body.
[0014] Preferably, the cardboard conveying mechanism includes a conveyor body and a plurality
of pressure rollers.
[0015] The conveyor body has a front-end conveying wheel, a back-end conveying wheel, and
a conveyor belt looped around the front-end conveying wheel and the back-end conveying
wheel. Cardboard can be placed on the conveyor belt in order to be coated.
[0016] The pressure rollers are provided above the conveyor body such that cardboard can
be held between the conveyor belt and the pressure rollers.
[0017] Preferably, the coating machine further includes a wax trough below the wax dispenser
and the two wax dispensing rollers.
[0018] Preferably, the front end of the cardboard conveying mechanism is provided with a
cardboard holder, and the cardboard holder has an inclined cardboard-supporting table.
[0019] Preferably, the back end of the cardboard conveying mechanism is provided with a
transport mechanism that includes a front-end transport wheel, a middle transport
wheel, and a rear-end transport wheel. Both the front-end transport wheel and the
rear-end transport wheel are lower than the middle transport wheel. A first transport
belt is looped around the front-end transport wheel and the middle transport wheel
while a second transport belt is looped around the middle transport wheel and the
rear-end transport wheel.
[0020] Preferably, the rear-end transport wheel is lower than the front-end transport wheel.
[0021] Preferably, a cardboard collector is provided near the rear-end transport wheel.
[0022] Preferably, the coating machine further includes a wax reservoir for storing liquid
wax. The wax reservoir is connected to the wax dispenser through a pump and is below
the wax trough.
[0023] The present invention also provides the coating method of the foregoing coating machine,
wherein the coating method includes the steps of:
- a) placing cardboard on the cardboard conveying mechanism such that the wax dispenser
is vertically aligned with a forward edge of the cardboard;
- b) turning on the wax dispenser and the cardboard conveying mechanism in order for
the wax dispenser to dispense wax to the forward edge and an upper surface of the
cardboard; and
- c) coating two lateral edges of the cardboard with wax by the wax dispensing rollers
on the two lateral sides of the wax dispenser respectively while the cardboard is
moved from the front end of the cardboard conveying mechanism to the back end of the
cardboard conveying mechanism.
[0024] It is preferable that the cardboard is heat-insulating cardboard, that the heat-insulating
cardboard includes a cardboard body and a heat-insulating material adhesively bonded
to each other, and that an outer surface of the cardboard body as well as two lateral
edges and a forward edge of the heat-insulating cardboard is to be coated with wax.
[0025] It is preferable that the cardboard body is 0.3 mm∼9 mm thick.
[0026] It is preferable that the heat-insulating material is 1 mm∼6 mm thick.
[0027] The coating machine and coating method of the present invention have the following
features and advantages: The two wax dispensing rollers can wax two lateral edges
of a sheet of cardboard respectively while the wax dispenser dispenses wax evenly
over the upper surface and forward edge of the cardboard, and this effectively ensures
that the coated cardboard is waterproofed as a whole. Aside from being able to wax
an entire sheet of cardboard, the invention is structurally simple, easy to perform,
and highly automated.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0028] To expound the technical solutions provided by embodiments of the present invention,
a brief description of the accompanying drawings, to which the following embodiments
refer, is given below. It is understood that the accompanying drawings show only some
embodiments of the invention, and that a person of ordinary skill in the art may derive
other drawings from the accompanying ones without creative labor.
FIG. 1 schematically shows the structure of a coating machine according to the present
invention.
FIG. 2 schematically shows the structure of a wax dispensing roller of the coating
machine in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0029] The technical solutions provided by embodiments of the present invention are detailed
below with reference to the accompanying drawings. It is understood that the embodiments
described herein are only some illustrative ones, and do not include all the possible
embodiments, of the invention. All other embodiments achievable by a person of ordinary
skill in the art without creative labor should fall within the scope of patent protection
sought by the present applicant.
Embodiment 1
[0030] As shown in FIG. 1, the present invention provides a coating machine that includes
a cardboard conveying mechanism 1 and a wax dispenser 2. The cardboard conveying mechanism
1 has a front end 11 and a back end 12, wherein the front end 11 is lower than the
back end 12. The wax dispenser 2 is provided above the back end 12, and a wax dispensing
roller 3 is provided on each of two lateral sides of the wax dispenser 2.
[0031] More specifically, the cardboard conveying mechanism 1 includes a conveyor body 4
and a plurality of pressure rollers 5. The conveyor body 4 has a front-end conveying
wheel 41, a back-end conveying wheel 42, and a conveyor belt 43 looped around the
front-end conveying wheel 41 and the back-end conveying wheel 42. Cardboard 10 can
be placed on the conveyor belt 43 in order to be coated. The cardboard 10 may be a
single- or multi-ply composite cardboard having a thickness ranging from 0.3 mm to
9 mm; the present invention has no limitation in this regard. The pressure rollers
5 are provided above the conveyor body 4 in such a way that the cardboard 10 can be
held between the conveyor belt 43 and the pressure rollers 5.
[0032] The wax dispenser 2 is located above the back end 12 of the cardboard conveying mechanism
1 and has a wax outlet 21 lying above the back-end conveying wheel 42 of the cardboard
conveying mechanism 1. The wax outlet 21 of the wax dispenser 2 is a slit whose length
corresponds to the width of the cardboard 10. When the cardboard 10 is conveyed to
the back-end conveying wheel 42 (i.e., when the forward edge of the cardboard 10 is
vertically aligned with the wax outlet 21 of the wax dispenser 2), the wax dispenser
2 is turned on, allowing the liquid wax in the wax dispenser 2 to curtain-coat the
cardboard 10 through the wax outlet 21. In the present invention, the wax dispenser
2 is connected to a wax reservoir 7 through a pump 6. The wax reservoir 7 contains
liquid wax, and the pump 6 can pump the liquid wax in the wax reservoir 7 into the
wax dispenser 2.
[0033] Once turned on, the front-end conveying wheel 41 and the back-end conveying wheel
42 of the cardboard conveying mechanism 1 are rotated and thereby move the cardboard
10 from the front end 11 to the back end 12 of the cardboard conveying mechanism 1
via the conveyor belt 43. As the front end 11 is lower than the back end 12 (i.e.,
the conveyor belt 43 is inclined at a certain angle), the cardboard 10 is conveyed
slantingly upward such that the liquid wax in the wax dispenser 2 above the back end
12 falls as a curtain on the forward edge of the cardboard 10. Meanwhile, constant-speed
movement of the cardboard 10 along the cardboard conveying mechanism 1 allows the
liquid wax falling from the wax dispenser 2 to curtain-coat the entire upper surface
of the cardboard 10. As a result, the upper surface as well as the forward edge of
the cardboard 10 is evenly coated with liquid wax. It is worth mentioning that, during
the conveying process, the pressure rollers 5 hold the cardboard 10 against the conveyor
belt 43 to prevent the cardboard 10 from sliding off the conveyor belt 43.
[0034] The two wax dispensing rollers 3, which are provided on the two lateral sides of
the wax dispenser 2 respectively, are spaced apart by a distance equivalent to the
width of the cardboard 10 so as to contact two lateral edges of the cardboard 10 respectively.
In the present invention, as shown in FIG. 2, each wax dispensing roller 3 includes
a roller body 31 and a felt sleeve 32. The roller body 31 has a hollow chamber in
communication with the wax dispenser 2 through a connecting tube 33. The roller body
31 is also provided with a plurality of through holes 311 in communication with the
hollow chamber. The felt sleeve 32 is mounted around the roller body 31.
[0035] More specifically, the wax dispensing roller 3 has a fixing frame 34. The roller
body 31 is rotatably connected to the fixing frame 34 via bearings provided respectively
at two ends of the roller body 31. The roller body 31 is generally cylindrical and
has its upper end connected to the wax dispenser 2 through the connecting tube 33
in order for the liquid wax in the wax dispenser 2 to flow through the connecting
tube 33 into the hollow chamber of the roller body 31. The through holes 311 are provided
in the peripheral wall of the roller body 31 and are in communication with the hollow
chamber so that the liquid wax flowing into the hollow chamber of the roller body
31 can flow through the through holes 311 to the outer surface of the roller body
31.
[0036] The felt sleeve 32 is generally cylindrical, has an inner diameter slightly larger
than the outer diameter of the roller body 31, and is mounted around the outer surface
of the roller body 31 so as to rotate along with the roller body 31. While the roller
body 31 is rotated, the felt sleeve 32 is in contact with the outer surface of the
roller body 31 and can also contact the corresponding lateral edge of the cardboard
10, thereby dispensing the liquid wax on the outer surface of the roller body 31 to
(i.e., waxing) the corresponding lateral edge of the cardboard 10.
[0037] The coating machine further includes a wax trough 8 below the wax dispenser 2 and
the two wax dispensing rollers 3 in order to collect excess liquid wax flowing out
of the wax dispenser 2 and the wax dispensing rollers 3. The wax trough 8 lies above
the wax reservoir 7, and the liquid wax in the wax trough 8 can flow into the wax
reservoir 7 through an outlet at the bottom of the wax trough 8.
[0038] In this embodiment of the present invention, the front end 11 of the cardboard conveying
mechanism 1 is provided with a cardboard holder 13. The cardboard holder 13 has an
inclined cardboard-supporting table 131 on which to place the cardboard 10 to be waxed
and that facilitates conveyance of the cardboard 10 by giving the cardboard 10 the
same inclination angle as the conveyor belt 43 before the cardboard 10 is fed into
the cardboard conveying mechanism 1.
[0039] Moreover, the back end 12 of the cardboard conveying mechanism 1 is provided with
a transport mechanism 9. The transport mechanism 9 includes a front-end transport
wheel 91, a middle transport wheel 92, and a rear-end transport wheel 93. Both the
front-end transport wheel 91 and the rear-end transport wheel 93 are lower than the
middle transport wheel 92. A first transport belt 94 is looped around the front-end
transport wheel 91 and the middle transport wheel 92 while a second transport belt
95 is looped around the middle transport wheel 92 and the rear-end transport wheel
93. In this embodiment, the rear-end transport wheel 93 is lower than the front-end
transport wheel 91.
[0040] Once turned on, the front-end transport wheel 91, the middle transport wheel 92,
and the rear-end transport wheel 93 of the transport mechanism 9 are rotated such
that the first transport belt 94 receives the curtain-coated cardboard 10 from the
cardboard conveying mechanism 1 and transports the cardboard 10 to the second transport
belt 95, which further transports the cardboard 10 to a cardboard collector 96 near
the rear-end transport wheel 93 to complete collection of the waxed cardboard 10.
[0041] The coating machine of the present invention is so designed that not only can the
wax dispenser 2 coat the upper surface and forward edge of the cardboard 10 evenly
with wax, but also the two wax dispensing rollers 3 can wax the two lateral edges
of the cardboard 10 respectively to ensure that the cardboard 10 is waterproofed as
a whole. In addition to the ability to wax the entire cardboard 10, the coating machine
features a simple structure and a high degree of automation.
Embodiment 2
[0042] With continued reference to FIG. 1 and FIG. 2, the present invention further provides
the coating method of a coating machine. The structures, working principle, and advantageous
effects of the coating machine in embodiment 2 are identical to those of the coating
machine in embodiment 1 and hence will be not be described repeatedly. The coating
method of the coating machine includes the following steps:
- a) Place the cardboard 10 on the cardboard conveying mechanism 1, with the wax dispenser
2 in vertical alignment with the forward edge of the cardboard 10;
- b) Turn on the wax dispenser 2 and the cardboard conveying mechanism 1 so that the
wax dispenser 2 dispenses wax to the forward edge and the upper surface of the cardboard
10; and
- c) Wax the two lateral edges of the cardboard 10 with the wax dispensing rollers 3
on the two lateral sides of the wax dispenser 2 respectively while the cardboard 10
is moved from the front end 11 of the cardboard conveying mechanism 1 to the back
end 12 of the cardboard conveying mechanism 1.
[0043] More specifically, the cardboard conveying mechanism 1 is inclined at a certain angle
such that the cardboard 10 placed thereon is inclined at the same angle.
[0044] Once turned on, the front-end conveying wheel 41 and the back-end conveying wheel
42 of the cardboard conveying mechanism 1 are rotated and thereby move the cardboard
10 from the front end 11 to the back end 12 of the cardboard conveying mechanism 1
via the conveyor belt 43. As the cardboard 10 is conveyed slantingly upward, the liquid
wax in the wax dispenser 2 above the back end 12 falls as a curtain on the forward
edge of the cardboard 10, and constant-speed movement of the cardboard 10 along the
cardboard conveying mechanism 1 allows the liquid wax falling from the wax dispenser
2 to also curtain-coat the entire upper surface of the cardboard 10. Consequently,
the upper surface as well as the forward edge of the cardboard 10 is evenly coated
with liquid wax. It is worth mentioning that, during the conveying process, the pressure
rollers 5 above the cardboard conveying mechanism 1 hold the cardboard 10 against
the conveyor belt 43 to prevent the cardboard 10 from sliding off the conveyor belt
43.
[0045] In the present invention, the cardboard 10 is heat-insulating cardboard that includes
a cardboard body and a heat-insulating material adhesively bonded to each other. The
liquid wax falling from the wax dispenser 2 can curtain-coat the outer surface of
the cardboard body and the forward edge of the heat-insulating cardboard, and each
of the two lateral edges of the heat-insulating cardboard can be coated by the wax
dispensing roller 3 on one of the two lateral sides of the wax dispenser 2. In the
present invention, the cardboard body has a thickness of 0.3 mm∼9 mm, and the heat-insulating
material has a thickness of 1 mm∼6 mm.
[0046] The coating method of the present invention not only dispenses wax to the upper surface
and forward edge of the cardboard 10, but also waxes the two lateral edges of the
cardboard 10 to effectively ensure waterproofness of the entire cardboard 10. Aside
from being capable of waxing the whole cardboard 10, the coating method is easy to
perform and features a high degree of automation.
[0047] The foregoing is only a couple of embodiments of the present invention. A person
skilled in the art may modify or change the disclosed embodiments in many ways according
to the disclosure of the present specification without departing from the scope of
the invention.
1. A coating machine,
characterized by comprising:
a cardboard conveying mechanism (1) having a front end (11) and a back end (12), wherein
the front end (11) is lower than the back end (12); and
a wax dispenser (2) provided above the back end (12) and provided with a wax dispensing
roller (3) on each of two lateral sides of the wax dispenser (2).
2. The coating machine of claim 1,
characterized in that each of the wax dispensing rollers (3) comprises:
a roller body (31) having a hollow chamber in communication with the wax dispenser
(2) through a connecting tube (33), the roller body (31) being provided with a plurality
of through holes(311) in communication with the hollow chamber; and
a felt sleeve (32) mounted around the roller body (31).
3. The coating machine of claim 1,
characterized in that the cardboard conveying mechanism (1) comprises:
a conveyor body (4) having a front-end conveying wheel (41), a back-end conveying
wheel (42), and a conveyor belt (43) looped around the front-end conveying wheel (41)
and the back-end conveying wheel (42) such that cardboard (10) is placeable on the
conveyor belt (43) in order to be coated; and
a plurality of pressure rollers (5) provided above the conveyor body (4) such that
the cardboard (10) is able to be held between the conveyor belt (43) and the pressure
rollers (5).
4. The coating machine of claim 1, characterized by further comprising a wax trough (8) below the wax dispenser (2) and the two wax dispensing
rollers (3).
5. The coating machine of claim 1, characterized in that the front end (11) of the cardboard conveying mechanism (1) is provided with a cardboard
holder (13), and that the cardboard holder r (13) has an inclined cardboard-supporting
table (131).
6. The coating machine of claim 1, characterized in that the back end (12) of the cardboard conveying mechanism (1) is provided with a transport
mechanism (9); that the transport mechanism (9) comprises a front-end transport wheel
(91), a middle transport wheel (92), and a rear-end transport wheel (93); that the
front-end transport wheel (91) and the rear-end transport wheel (93) are lower than
the middle transport wheel (92); and that there are a first transport belt (94) looped
around the front-end transport wheel (91) and the middle transport wheel (92) and
a second transport belt (95) looped around the middle transport wheel (92) and the
rear-end transport wheel (93).
7. The coating machine of claim 6, characterized in that the rear-end transport wheel (93) is lower than the front-end transport wheel (91).
8. The coating machine of claim 6, characterized in that a cardboard collector (96) is provided near the rear-end transport wheel (93).
9. The coating machine of claim 4, characterized by further comprising a wax reservoir (7) for storing liquid wax, wherein the wax reservoir
(7) is connected to the wax dispenser (2) through a pump (6) and is below the wax
trough (8).
10. A coating method of the coating machine of any of claims 1-9,
characterized by comprising the steps of:
a) placing the cardboard (10) on the cardboard conveying mechanism (1) such that the
wax dispenser (2) is vertically aligned with a forward edge of the cardboard (10);
b) turning on the wax dispenser (2) and the cardboard conveying mechanism (1) in order
for the wax dispenser (2) to dispense wax to the forward edge and an upper surface
of the cardboard (10); and
c) coating two lateral edges of the cardboard (10) with wax by the wax dispensing
rollers (3) on the two lateral sides of the wax dispenser (2) respectively while the
cardboard (10) is moved from the front end (11) of the cardboard conveying mechanism
(1) to the back end (12) of the cardboard conveying mechanism (1).
11. The coating method of claim 10, characterized in that the cardboard (10) is heat-insulating cardboard, that the heat-insulating cardboard
comprises a cardboard body and a heat-insulating material adhesively bonded to each
other, and that an outer surface of the cardboard body as well as two lateral edges
and a forward edge of the heat-insulating cardboard is to be coated with wax.
12. The coating method of claim 11, characterized in that the cardboard body has a thickness of 0.3 mm∼9 mm.
13. The coating method of claim 11, characterized in that the heat-insulating material has a thickness of 1 mm~6 mm.