Information
-
Patent Grant
-
6604340
-
Patent Number
6,604,340
-
Date Filed
Tuesday, May 1, 200123 years ago
-
Date Issued
Tuesday, August 12, 200320 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Rada; Rinaldi I.
- Desai; Hemant M.
Agents
-
CPC
-
US Classifications
Field of Search
US
- 053 3735
- 053 3737
- 053 3743
- 053 3746
- 053 3748
- 053 3756
- 053 562
- 053 568
-
International Classifications
-
Abstract
A packaging machine for packaging an article having a lateral side along which a sealing line is formed by heat sealing operation is disclosed. The packaging machine includes a machine frame having transversely-extending rails on which a conveyor for carrying the article and a package film for packaging the article is movably supported whereby the conveyor and thus the article and the package film are transversely position-adjustable. A side sealing device includes a film forwarding device for synchronously moving the package film with the article in a longitudinal direction. A position-adjusting device comprises a support structure attached to the conveyor to be transversely position-adjustable. A movable chassis is movably coupled to the support structure by means of a screw rod whereby rotation of the screw rod moves the chassis with respect to the support structure in a vertical direction. A heat sealing blade is supported on the chassis by an actuation device to be reciprocally movable between an extending position for performing heat sealing operation on an edge of the package film along the side of the article to form the sealing line and a retracted position. The heat sealing blade is movable with the chassis for adjusting the position with respect to the article in the vertical direction.
Description
FIELD OF THE INVENTION
The present invention generally relates to a packaging machine with heat sealing device for packaging articles with heat sealing film, and in particular to a packaging machine capable to accommodate different sizes of articles to be packaged.
BACKGROUND OF THE INVENTION
Package films made of plastics or other heat sealable materials are widely used in packaging a variety of products, such as foods, compact disks for computer software and music and books, to protect the products from being damaged or contaminated. In a packaging process, a package film is placed around an article to be packaged. Edges of the package film is then heated to seal along sides of the article. Thus, an important factor that influences the productivity of a packaging line is the heat sealing operation performed by a packaging machine.
A conventional packaging machine forms an L-shaped sealing line along two adjacent sides of an article to be packaged. In other words, it seals two sides simultaneously. However, the operation of the packaging machine is intermittent. The productivity is limited. Furthermore, articles to be packaged may have variable sizes and shapes. This causes deficiency in final package made by the conventional packaging machine. For example, as shown in
FIGS. 11 and 12
, due to different thickness (dimension in a vertical direction) of the article to be packaged, a sealing line A or A′ may not be located midway of the thickness of an article B. They may be below (sealing line A) or above (sealing line A′) the middle line. Such a situation may cause certain problems. For example, the sealing line may not be properly formed or the package film be damaged or undesired over-packaging be caused. Eventually, the quality of the products is negatively affected.
In a packaging line, articles to be packaged are usually transported by a conveyor system in a longitudinal direction. One way to accommodate articles of different thickness (vertical dimension) to a particular packaging machine is to change the vertical position of the conveyor belt with respect to the packaging machine. This is, however, difficult and ineffective. Modifying a conveyor system to suit for different articles is also very impractical because the packaging line may sometimes constitute only a part of a complete manufacturing line. Changing the conveyor system for the packaging line may cause serious problem to the other portions of the same manufacturing line.
Another disadvantage associated with the above-discussed conventional packaging machine is that the L-shaped sealing line formed by the packaging machine is subject to limitation of size of the particular packaging machine. For articles having elongate lateral side dimension, it is difficult to package the articles with regular packaging machines that forms L-shaped sealing lines.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a packaging machine comprising a sealing line adjusting device for adjusting the sealing line with respect to the size of an article to be packaged.
Another object of the present invention is to provide a packaging machine comprising a side sealing device for continuously forming sealing lines along sides of articles.
A further object of the present invention is to provide a packaging machine comprising a side sealing device for forming a side sealing line without causing damage to the package or the package film.
A still further object of the present invention is to provide a packaging machine comprising a side sealing device for forming a continuous side sealing line of unlimited length.
To achieve the above objects, in accordance with the present invention, there is provided a packaging machine for packaging an article having a lateral side along which a sealing line is formed by heat sealing operation. The packaging machine comprises a machine frame having transversely-extending rails on which a conveyor for carrying the article and a package film for packaging the article is movably supported whereby the conveyor and thus the article and the package film are transversely position-adjustable. A side sealing device comprises a film forwarding device for synchronously moving the package film with the article in a longitudinal direction. A position-adjusting device comprises a support structure attached to the conveyor to be transversely position-adjustable. A movable chassis is movably coupled to the support structure by means of a screw rod whereby rotation of the screw rod moves the chassis with respect to the support structure in a vertical direction. A heat sealing blade is supported on the chassis by an actuation device to be reciprocally movable between an extending position for performing heat sealing operation on an edge of the package film along the side of the article to form the sealing line and a retracted position. The heat sealing blade is movable with the chassis for adjusting the position with respect to the article in the vertical direction.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, in which:
FIG. 1
is a perspective view, partially broken, of a side sealing device of a packaging machine constructed in accordance with the present invention;
FIG. 2
is a side elevational view of the side sealing device, together with a conveyance device, of the packaging machine of the present invention;
FIG. 3
is a top view of the packaging machine of the present invention;
FIG. 4
is similar to
FIG. 3
, showing transverse movement of the conveyance device with respect to a machine frame of the packaging machine;
FIG. 5
is a perspective view of a portion of the side sealing device viewed from a different perspective;
FIG. 6
is a front side elevational view of
FIG. 1
;
FIG. 7
is a rear side elevational view of
FIG. 1
;
FIG. 8
is a schematic view showing a device for maintaining proper torque transmitted between the conveyance device and the film forwarding device of the packaging machine of the present invention;
FIG. 9
is a top view showing an article is packaged with a package film by the packaging machine of the present invention;
FIG. 10
is a schematic view showing the adjustment of the vertical position of the side sealing device of the present invention; and
FIGS. 11 and 12
are schematic views showing sealing lines formed by a conventional packaging machine located below and above middle line of the thickness of an article.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the drawings and in particular to
FIGS. 2-4
, a packaging machine in which a side sealing device in accordance with the present invention is incorporated is shown. The packaging machine comprises a machine frame
10
having a plurality of rails
11
extending in a transverse direction to support a conveyance system
20
. The conveyance system
20
may comprise conveyor of be any known type, such as belt or chain conveyor. In the embodiment illustrated, the conveyance system
20
is operated by a power driving device
21
, including for example an electrical motor having an output spindle (not labeled) mechanically coupled by a chain
211
to a shaft
22
for driving a conveyor belt
23
. The conveyor belt
23
carries and transports, in a longitudinal direction, an article
300
to be packaged and a package film
200
which will be wrapped around the article
300
. The conveyor
20
is movable along the rails
11
in the transverse direction for accommodating articles
300
of different sizes and package film
200
of different width.
Also referring to
FIG. 1
, the side sealing device constructed in accordance with the present invention, generally designated with reference numeral
100
, comprises a base plate
30
separated from and thus movable with respect to the conveyor
20
. A film forwarding device is attached to the base plate
30
, comprising two pairs of guide rollers
31
and a pair of driving rollers
32
mounted on a front surface (not labeled) of the base plate
30
. The guide rollers
31
are mechanically coupled to each other by belts
311
so that they are rotatable in unison with each other. A pair of mated gears
312
are arranged on a rear side (not labeled) of the base plate
30
and co-axially fixed to the guide rollers
31
so that the gears
312
are rotatable with the guide rollers
31
. A first pinion
313
is co-axially fixed to the shaft of one of the guide wheels
31
. The first pinion
313
is mechanically coupled to a second pinion (not labeled) mounted on the shaft
22
of the conveyor
20
by a timing belt
314
whereby the guide rollers
31
, the gears
312
and the pinions
313
are rotatable in synchronization with each other by being driven by the driving device
21
. The operation of the guide rollers
31
and the conveyor
20
is thus kept synchronous. Quite obviously, the pinion-timing belt pair may be replaced by sprocket-chain pair.
Also referring to
FIGS. 5 and 6
, gaps X and Y are formed between each pair of guide rollers
31
and the driving rollers
32
to allow an edge of the package film
200
to pass therethrough. The gaps X and Y are sized to frictionally engage the edge of the package film
200
for driving the package film
200
forward in the longitudinal direction whereby the package film
200
may move in synchronization with the conveyor belt
23
of the conveyor
20
.
A shielding member
33
in the form of a box is disposed between the guide roller pairs
31
. A slit
332
is defined in a side wall of the shielding member
33
and extends between the guide roller pairs
31
forming a passage for the package film
200
. An opening
331
is defined in a top side of the shielding member
33
, forming an entrance for a heat sealing blade
50
to allow the heat sealing blade
50
to approach, contact and heat-seal the edge of the package film
200
along one side of the article
300
. A sealing line is thus formed along the side of the article
300
.
Also referring to
FIGS. 7 and 8
, a position adjusting device
40
comprises a movable chassis
41
fixed to the rear face of the base plate
30
. Two blocks
411
,
412
are arranged on opposite sides of the chassis
41
and are fixed to the rear face of the base plate
30
. A support structure comprises upper and lower support plates
42
,
43
respectively arranged above and below the chassis
41
and the blocks
411
,
412
and two guide posts
45
,
46
extending between the support plates
42
,
43
. The lower support plate
43
are attached to the conveyor
20
. The guide posts
45
,
46
extend through bores (not labeled) defined in the blocks
411
,
412
for guiding movement of the blocks
411
,
412
, as well as the chassis
41
and the base plate
30
, with respect to the lower support plate
43
and thus the conveyor
20
in a vertical direction.
An operating device comprises a screw rod
44
extending from the upper support plate
42
to the lower support plate
43
and rotatably supported by the upper and lower support plates
42
,
43
. The screw rod
44
threadingly engages an inner-threaded hole (not labeled) defined in the chassis
41
whereby when the screw rod
44
is rotated, the chassis
41
is linearly moved in the vertical direction, by being guided by the posts
45
,
46
, with respect to the upper and lower support plates
42
,
43
and thus the conveyor
20
. Thus, the position of the side sealing device
100
with respect to an article
300
carried by the conveyor belt
23
is adjusted as indicated by arrows of
FIGS. 2 and 7
. This allows the vertical position of a side sealing line with respect to the thickness of the article
300
to be changed by moving the chassis
41
with respect to the conveyor
20
.
A hand wheel
441
is mounted to the screw rod
44
above the upper support plate
42
for manual rotation of the screw rod
44
. The hand wheel
441
can be replaced by other power driving devices, such as electrical motor and pneumatic or hydraulic device. At least a stop member
442
is attached to the screw rod
44
for limiting the linear movement of the chassis
41
with respect to the support plates
42
,
43
. In the embodiment illustrated, the stop member
442
comprises a nut threadingly engaging the screw rod
44
. It is understood that the nut can be replaced by other suitable means.
As best shown in
FIG. 8
, the position adjusting device
40
comprises means for preventing the chain
314
from loosening during the positional adjustment of the chassis
41
with respect to the conveyor
20
. A bar
47
is pivotally mounted to the block
411
having first and second ends on opposite sides of the pivot point. A third pinion or sprocket
472
is rotatably supported on the first end of the bar
47
and engaging the timing belt or chain
314
whereby the first, second and third pinions or sprockets
313
,
472
and the timing belt or chain
314
form a triangle with the pinions or sprockets located at the corners of the triangle. A biasing member
471
, such as a helical spring, is connected between the second end of the bar
47
and the block
411
for mechanically biasing the bar
47
in such a way to keep a desired tension on the timing belt or chain
314
. Maintaining the desired level of tension on the timing belt or chain
314
allows the rotational movement of the shaft
22
of the driving device
21
to be effectively and stably transmitted to the first pinion
313
and thus the guide wheels
31
for driving the package film
200
forward in synchronization with the conveyor
20
.
The heat sealing blade
50
can be of any type as long as it is capable to effectively heat sealing the package film
200
and forming a sealing line along the side of the article
300
. The heat sealing blade
50
is supported by an arm
51
(FIG.
1
). An actuation device
53
, such as a solenoid and a pneumatic cylinder, is mounted to the chassis
41
and has an elongate driving rod
531
that is capable to move with respect to the chassis
41
by being driven by the actuation device
53
between extended and retracted positions. The arm
51
is fixed to the driving rod
531
whereby the heat sealing blade
50
is movable with the chassis
41
when the driving rod
531
is kept fixed during the adjustment of the position of the chassis
41
with respect to the conveyor
20
. When the actuation device
53
is activated, the driving rod
531
moves the heat sealing blade
50
, via the arm
51
, into and out of the shielding member
33
for engaging and sealing the package film
200
. In the embodiment illustrated, when the driving rod
531
is moved to the retracted position, the heat sealing blade
50
is moved into the shielding member
33
to contact and thus heat-seal the edge of the package film
200
and when the driving rod
531
is moved to the extended position, the heat sealing blade
50
is moved out of the shielding member
33
and thus separated from the package film
200
.
Two guide rods
52
are provided on opposite sides of the driving rod
531
and extend through holes (not labeled) defined in the arm
51
for guiding the movement of the heat sealing blade
50
.
Also referring to
FIGS. 9 and 10
, when the article
300
is carried and moved by the conveyor
20
(not shown in FIGS.
9
and
10
), the package film
200
is synchronously driven by the guide rollers
31
and the driving rollers
32
of the side sealing device
100
. The heat sealing blade
50
is operated by the actuation device
53
to continuously form a sealing line along one side of the article
300
. By moving the conveyor
20
and the side sealing device
100
with respect to the machine frame
10
along the rails
11
, articles
300
of different width can be accommodated in the packaging machine and by operating the hand wheel
411
, the position of the side sealing device
100
with respect to the article
300
is adjusted, thus forming sealing line at proper position along one side of the article
300
. In other words, the position of the sealing line with respect to the article
300
is adjustable by operating the hand wheel
411
, such as lines C and C′ of FIG.
10
. Thus articles of different width and different thickness can be properly packaged by means of the packaging machine incorporating the side sealing device of the present invention.
Although the present invention has been described with reference to the preferred embodiment thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. For example, an independent driving device may be adapted to independently drive the guide wheels
31
. The shielding member
33
may be removed without substantially affecting the operation of the packaging machine. The hand wheel
441
may be replaced by an electrical motor. Furthermore, if desired, the guide rollers
31
and the driving rollers
32
may be omitted and the package film can be directly driven by a heat sealing mechanism that is different from the blade described herein.
Claims
- 1. A packaging machine comprising:a machine frame comprising rails; a conveyance device movable along the rails and comprising a transportation belt driven by a driving device having a rotatably driven shaft, the transportation belt being adapted to carry and move an article forward; and a side sealing device comprising: a film forwarding device comprising a plurality of roller pairs adapted to continuously pass an edge of a package film therebetween and drive the package film forward in synchronization with the transportation belt, a pair of meshingly engaged gears respectively coaxially coupled to one of the pair of rollers, and a first pinion gear coaxially mounted to one of the pair of gears and coupled to a second pinion gear coupled to the shaft of the driving means by a chain; a position adjusting device comprising a support structure attached to the conveyance device, a chassis coupled to an operating device to be selectively moved with respect to the support structure, the film forwarding device being mounted to and movable with the chassis for adjusting relative position of the film forwarding device with respect to the conveyance device, the position adjusting device including (a) a bar pivotally coupled to the film forwarding device, (b) a third pinion gear rotatably mounted to one end of the bar and engaged with the chain, and (c) a spring coupled to the bar to maintain the chain in tensioned engagement with the first, second, and third pinion gears through out the movement of the film forwarding device; and a heat sealing device comprising an actuation device mounted to the chassis, a heat sealing member attached to and selectively moved by the actuation device between a first position where the heat sealing member contacts and thus heat-seals the edge of the package film and a second position where the heat sealing member is moved away from the package film.
- 2. The packaging machine as claimed in claim 1, wherein the driving device comprises a motor.
- 3. The packaging machine as claimed in claim 1, wherein the roller pairs are mechanically coupled together by belts.
- 4. The packaging machine as claimed in claim 1, wherein the side sealing device comprises a shielding member defining an opening into which the heat sealing member is movable.
- 5. The packaging machine as claimed in claim 4, wherein the shielding member defines a slit through which the film passes.
- 6. The packaging machine as claimed in claim 1, wherein the actuation device comprises a driving rod to which an arm is fixed, the heat sealing member being attached to the arm to be movable therewith.
- 7. The packaging machine as claimed in claim 6, wherein guide rods are formed on the chassis and extend through holes defined in the arm for guiding the movement of the heat sealing member.
- 8. The packaging machine as claimed in claim 1, wherein the actuation device comprises a solenoid.
- 9. The packaging machine as claimed in claim 1, wherein the actuation device comprises a pneumatic cylinder.
- 10. A packaging machine comprising:a machine frame comprising rails; a conveyance device movable along the rails and comprising a transportation belt adapted to carry and move an article forward; and a side sealing device comprising: a film forwarding device comprising a plurality of roller pairs adapted to continuously pass an edge of a package film therebetween and drive the package film forward in synchronization with the transportation belt; a position adjusting device comprising a support structure attached to the conveyance device, a chassis coupled to an operating device to be selectively moved with respect to the support structure, the film forwarding device being mounted to and movable with the chassis for adjusting relative position of the film forwarding device with respect to the conveyance device, the operating device of the position adjusting device including (a) a screw rod rotatably supported on the support structure and threadingly engaging an inner-threaded hole defined in the chassis whereby rotating the screw rod causes the chassis to move with respect to the support structure, and (b) a stop member coupled to the screw rod to limit the movement of the chassis; and, a heat sealing device comprising an actuation device mounted to the chassis, a heat sealing member attached to and selectively moved by the actuation device between a first position where the heat sealing member contacts and thus heat-seals the edge of the package film and a second position where the heat sealing member is moved away from the package film.
- 11. The packaging machine as claimed in claim 10, wherein the stop member comprises a nut threadedly engaging the screw rod.
US Referenced Citations (9)