Abstrict A desiccant pack 1 with a humidity sensor comprises a pack body
10 formed by sealing the three opened sides of a package film having
gas permeability and heat sealability, and a desiccant is filled
inside the pack body 10. Humidity sensor substances are applied
in a band or strip-shape to the surface of the pack body 10 by
which humidity sensors 21 22 and 23 are applied directly to the
pack.
Claims We claim:
1. A desiccant pack with a humidity sensor comprising:
a pack body having a set of sides and corresponding edges arranged
about a pack body inner surface and outer surface, each side formed
by a row of two or more side portions, with one side having a portion
being folded in upon itself along a lateral edge and with the other
remaining sides being heat sealed along their lateral edges;
a desiccant filled inside the inner surface on said pack body;
and
a humidity sensor substance being applied directly onto the outer
surface of said pack body, which substance manifests an observable
moisture sensitive reaction and changes its color according to a
varying ambient level of relative humidity.
2. A desiccant pack with a humidity sensor defined in claim 1
wherein said humidity sensor substance is applied in the shape of
a band parallel to said side portion of the pack body being folded.
3. A desiccant pack with a humidity sensor defined in claim 2
wherein said humidity sensor substance includes a plurality of substances
which react to different humidity levels respectively and change
their color accordingly, said plurality of substances being applied
in plural bands.
4. A manufacturing device of a desiccant pack with a humidity sensor
comprising:
a package film manufacturing device including a supply roll for
sending out a band-shaped package film base, and a humidity sensor
application device for applying a liquid-state humidity sensor substance
to the surface of a package film; and
a pack manufacturing device connected to said package film manufacturing
device, said pack manufacturing device including a center seal device
for folding the supplied package film at the center portion in the
width direction of said film and heat-sealing both side ends thereof,
a hopper for measuring a desiccant and filling the same in said
package film being center-sealed, an end seal device for heat-sealing
the front and back side ends of said package film, and a cutter
for separating said heat-sealed package film to individual packs.
5. A manufacturing device of a desiccant pack with a humidity sensor
defined in claim 4 wherein said humidity sensor application device
comprises a plurality of humidity sensor units, each unit comprising
a container storing said liquid-state humidity sensor substance,
an application roller to which said humidity sensor substance is
adhered, and a backup roller opposing to said application roller,
wherein said humidity sensor substance is applied onto the surface
of said package film being conveyed between said application roller
and said backup roller.
6. A manufacturing device of a desiccant pack with a humidity sensor
defined in claim 5 wherein said manufacturing device includes an
air cylinder for driving said application roller to contact to or
separate from said backup roller.
Description FIELD OF THE INVENTION
The present invention relates to a desiccant pack with a humidity
sensor, and the method of manufacturing the same.
DESCRIPTION OF THE PRIOR ART
Heretofore, it was common to enclose a pack having gas permeability
filled with a desiccant to a package enwrapping food and the like,
so as to reduce the humidity inside the package, and to prevent
the quality of the packed goods such as food from deteriorating.
Recently, it has become common to enclose a desiccant pack to a
plastic package having high sealability for conveying members such
as electronic parts and electronic appliances, which are adversely
affected by humidity.
It is necessary to control the humidity inside the package enwrapping
electronic parts and the like, and therefore, it is required that
the current humidity inside the package be detected.
In recent years, chemical substances are developed which change
their color according to the humidity in the air. By applying the
chemical substance onto a card and visually observing the change
of its color, one is able to know the humidity of the air. A variety
of chemical substances which react to different levels of humidity
may be prepared. If the variety of chemical substances are applied
in spots on one card, one is able to know the percentage of humidity
in the air according to the color of the spots.
Such card is known as a humidity indicator card. The humidity indicator
card may be enclosed together with the desiccant pack to a package
enwrapping electronic parts and the like, so as to check the humidity
of the air inside the package body.
SUMMARY OF THE INVENTION
According to the conventional method of enclosing the desiccant
pack and the humidity indicator card to a package body, the pack
and the card must be handled as a set, and it caused the rising
of cost.
Therefore, the present invention aims at providing a desiccant
pack with a humidity sensor integrated thereon and the corresponding
manufacturing device of the integrated desiccant pack humidity sensor
which solves the above-mentioned problems of the prior art.
The desiccant pack with a humidity sensor according to the present
invention comprises, as a basic means, a pack body with one side
portion being folded in upon itself along a lateral edge and other
three sides being heat sealed along their lateral edges, a desiccant
filled inside said pack body, and a humidity sensor substance being
applied directly onto the surface of said pack body, which changes
its color according to a varying ambient level of relative humidity.
Further, the humidity sensor substance is applied in the shape of
a band parallel to said side portion of the pack body being folded.
Moreover, the humidity sensor substance includes a plurality of
substances which react to different humidity levels respectively
and change their color accordingly, said plurality of substances
being applied in plural bands.
Next, the manufacturing device of the desiccant pack with a humidity
sensor according to the invention comprises a package film manufacturing
device including a supply roll for sending out a band-shaped package
film base, and a humidity sensor application device for applying
a liquid-state humidity sensor substance to the surface of a package
film, and a pack manufacturing device connected to said package
film manufacturing device, said pack manufacturing device including
a center seal device for folding the supplied package film at the
center portion in the width direction of said film and heat-sealing
both side ends thereof, a hopper for measuring a desiccant and filling
the same in said package film being center-sealed, an end seal device
for heat-sealing the front and back ends of said package film, and
a cutter for separating said heat-sealed package film to individual
packs. Further, the humidity sensor application device comprises
a plurality of humidity sensor units, each unit comprising a container
storing said liquid-phase humidity sensor substance, an application
roller to which said humidity sensor substance is adhered, and a
backup roller opposing to said application roller, wherein said
humidity sensor substance is applied onto the surface of said package
film being conveyed between said application roller and said backup
roller.
Moreover, the manufacturing device includes an air cylinder for
driving said application roller to contact to or separate from said
backup roller.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a perspective view of a desiccant pack with a humidity
sensor according to the present invention;
FIG. 2 is a front view of a manufacturing device of the desiccant
pack with a humidity sensor according to the present invention;
FIG. 3 is a left side view of the manufacturing device of the desiccant
pack with a humidity sensor according to the present invention;
and
FIG. 4 is a front view showing the main portion of the manufacturing
device of the desiccant pack with a humidity sensor according to
the present invention.
PREFERRED EMBODIMENT OF THE INVENTION
FIG. 1 is a perspective view showing the appearance of a desiccant
pack with a humidity sensor according to the present invention.
The desiccant pack with a humidity sensor shown as a whole by reference
number 1 is manufactured by a manufacturing device explained later.
A package film F having gas permeability is folded at its center
in the width direction, and the three other side ends of the film
are sealed by a heat seal HS, thereby forming a body 10.
A suitable desiccant (drying agent) is sealed inside the pack body
10. A generally used mineral such as a silica gel or a desicite
and the like is used as the desiccant.
On the surface of the pack body 10 is equipped a first sensor portion
21 which reacts to a humidity of, for example, 20% and changes its
color, a second sensor portion 22 which reacts to a humidity of
30%, and a third sensor portion 23 which reacts to a humidity of
40% and changes its color. Each sensor portion is formed by being
printed onto the surface of the package film F. Further, an indication
25 notifying the user that the package is equipped with a humidity
sensor is printed on the surface of the pack body 10.
A note indicating the type of the desiccant or a notice warning
that the desiccant is not edible is printed on the back surface
of the pack body 10.
Since a humidity sensor is directly printed on the surface of the
body 10 of the desiccant pack 1 by merely sealing the desiccant
pack in a package body for wrapping and protecting electronic parts
and the like, the dehumidification of the package in which electronic
parts are packed and the indication of the interior humidity of
the package may be achieved by a single desiccant pack. Accordingly,
the present invention provides a desiccant pack which is easy to
handle, and which contributes to cut down the cost of a package.
FIG. 2 is a front view of a manufacturing device of the desiccant
pack with a humidity sensor according to the present invention,
FIG. 3 is a left side view of FIG. 2 and FIG. 4 is a front view
of the main portion of FIG. 2.
The manufacturing device of the present invention is structured
by connecting in series a manufacturing device 100 of a package
film for forming a desiccant pack and a packaging device 300 of
a desiccant pack utilizing the package film.
The package film manufacturing device 100 comprises a power equipped
to the upper portion of a frame 110 and a control panel 105.
The frame 110 comprises a supply reel 120 of a base film, from
which the package film F is pulled out.
The package film F is a film having gas permeability and heat sealability
to which necessary letter patterns are printed in advance, which
is guided through various rollers equipped to the frame 110 to an
application device 130 for applying a humidity sensor substance.
FIG. 4 shows the details of the humidity sensor application device
130 comprising three containers 140 150 and 160 each storing a
liquid-state sensor substance.
Liquid-state humidity sensor substances which change color reacting
to humidity of different percentages respectively is stored in each
container. According to the present embodiment, a substance for
sensing a humidity of 40% is stored in the first container 140
a substance for sensing a humidity of 30% is stored in the second
container 150 and a substance for sensing a humidity of 20% is
stored in the third container 160.
The number of containers to be equipped to the device or the percentage
of humidity being sensed may be selected appropriately according
to need.
An application unit 143 for applying the sensor substance is mounted
to the first container 140. The unit 143 comprises a roller 144
which comes into contact with the sensor substance, and an application
roller 146. A package film F is sandwiched between the application
roller 146 and a backup roller 148. The application roller 146 is
moved by an air cylinder 142 to contact to or separate from the
backup roller 148. Application units 153 163 of the same kind for
applying the humidity sensor substances are each equipped to the
second container 150 and the third container 160 respectively.
As shown in FIG. 3 application rollers 146 156 and 166 of the
three sets of application units are placed so that their position
in the width direction of the package film F differ. The application
rollers apply the humidity sensor substances in a band or strip-shape
along a predetermined position in the width direction of the package
film F and in the direction that the package film F travels.
The package film F, to which the humidity sensor substances are
applied in a predetermined position, is sent to a drying chamber
174. A heated current of air which is generated in a heated air
generator 170 is blown out from a blowout opening 172. By the heated
air, the humidity sensor substances applied on the package film
F are dried.
A drive roll 180 operates to grip and transmit the package film
F. Since the dried humidity sensor substances have a unique color
tone, the application state and the dryness of the humidity sensor
substances are checked by a distinction sensor 200. The completed
package film F is sent to a packaging device 300.
The packaging device 300 comprises a power and a control panel
305 positioned inside a frame 310 and a motor 320 for driving each
mechanism.
The package film F supplied from the manufacturing device of the
package film is printed of necessary notes and marks in advance.
Therefore, a print position adjusting device 330 is used to adjust
the printed position in the longitudinal direction of the package
film F. The package film F completed of the positioning of the printing
is sent to a three-side sealing device.
The three-side sealing device is formed so as to fold the package
film at the width-direction center of the film, apply a center seal
thereto so as to form a cylinder-shaped film, fill a predetermined
amount of desiccant in the cylindrical film, and seal the opened
front and back side ends of the film (end-seal), thereby manufacturing
a pack.
The desiccant is placed inside a material tank 350 divided into
predetermined amounts by a measurement device 360 and filled through
a hopper 370 to the cylindrical package film. The package film,
provided of the center seal and the end seal between the heat roll
380 and the pull roll 390 is then separated to individual packs
by a rotary cutter 400 and discharged from a chute 410 as a desiccant
pack with a humidity sensor 1 explained with reference to FIG. 1.
The desiccant pack with a humidity sensor according to the present
invention is formed by directly printing a humidity sensor onto
the surface of a pack filled with a desiccant. Therefore, merely
by placing the desiccant pack alone into a package body, the internal
humidity of the package body may be indicated and the dehumidification
of the package body may be performed at the same time. Accordingly,
the electronic parts and the like which is packed inside the package
body is protected from humidity, and the quality of the packed goods
during distribution is secured.
Moreover, the manufacturing device of the desiccant pack with a
humidity sensor characterizes in preparing a base paper of a package
film of the desiccant pack in a roll-like shape, applying the liquid-type
humidity sensor substance automatically to the surface of the base
paper, drying the substance and then sending the film out to a three-side
seal device, sealing the three opened sides of the package film,
and then automatically filling a predetermined amount of desiccant
inside the film.
By using the device, the desiccant pack with a humidity sensor
according to the invention may be manufactured automatically.
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