U.S. patent application number 10/481163 was filed with the patent office on 2005-01-20 for machine for vacuum packing products in plastic bags or rigid containers.
Invention is credited to Germano, Maina.
Application Number | 20050011166 10/481163 |
Document ID | / |
Family ID | 11446827 |
Filed Date | 2005-01-20 |
United States Patent
Application |
20050011166 |
Kind Code |
A1 |
Germano, Maina |
January 20, 2005 |
Machine for vacuum packing products in plastic bags or rigid
containers
Abstract
A machine (1) for vacuum packing in plastic bags and rigid
containers (37) comprising:--an airtight chamber (4), suited to
accommodate a plastic bag (26) with the relative product
(27),--means for sucking air from said chamber (4), so as to create
a vacuum in the chamber and in the bag (26) contained
therein,--means for sealing the edges (25) of the bag (6) after the
vacuum has been created therein,--air input means (13) for
introducing air into the chamber (4) to remove the vacuum,--a
suction device (35), connected to the suction means, for creating
vacuum in rigid containers (37) provided with a valve (39).
Inventors: |
Germano, Maina; (Vaprio
D'Adda, IT) |
Correspondence
Address: |
SHERIDAN ROSS PC
1560 BROADWAY
SUITE 1200
DENVER
CO
80202
|
Family ID: |
11446827 |
Appl. No.: |
10/481163 |
Filed: |
September 10, 2004 |
PCT Filed: |
October 9, 2001 |
PCT NO: |
PCT/EP01/11678 |
Current U.S.
Class: |
53/512 |
Current CPC
Class: |
B65B 31/024 20130101;
B65B 31/047 20130101 |
Class at
Publication: |
053/512 |
International
Class: |
B65B 031/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 9, 2001 |
IT |
MI2001A000270 |
Claims
1. A machine for vacuum packing products in plastic bags and rigid
containers comprising: an airtight chamber, suited to receive a
plastic bag with the relative product, sucking means for sucking
air from said chamber, so as to create a vacuum inside said chamber
and said bag contained therein; sealing means for sealing the edges
of the bag after a vacuum has been created therein, air input means
able to introduce air into said chamber to remove the vacuum, a
suction device connected to said suction means, for creation of a
vacuum in rigid containers provided with a valve.
2. A machine according to claim 1, characterized in that said
chamber is formed in a basic body or base of the machine and is
closed by a cover, sealing means able to ensure an airtight seal
being provided between the base and the cover.
3. A machine according to claim 2, characterized in that said
sealing means comprise a gasket made in a single piece, with a
lip-shaped cross-section to compensate for errors in planarity
between the cover and the base body.
4. A machine according to claim 1, characterized in that said
suction device is connected to said sucking means by a flexible
tube, to create a vacuum in said chamber.
5. A machine according to claim 4, characterized in that said
flexible tube is wound on a spring-loaded tube-winding device
disposed inside a housing separated from said chamber in which the
vacuum is created.
6. A machine according to claim 4, characterized in that said
suction device is housed in a seat of said machine in which a
connector communicating with said chamber is provided.
7. A machine according to claim 1, characterized in that said
sucking means for sucking air from said chamber comprise a pump,
operated by a motor, which pump by means of said suction device
sucks air from said chamber through at least one opening made in
said chamber.
8. A machine according to claim 7, characterized in that said pump
comprises two piston-cylinder assemblies working in push-pull
fashion.
9. A machine according to claim 7, characterized in that interposed
between the motor and the pump is a reduction unit comprising a
pinion splined to the shaft of the motor which meshes with a first
gear wheel mounted on a first shaft on which is mounted a second
gear wheel which meshes with a third gear wheel mounted on a second
shaft which carries two cams for movement of the connecting rods of
the pistons.
10. A machine according to claim 1, characterized in that said
means for sealing the free edge of the bag comprise a welding bar
extending in crosswise direction of the edge of the bag and means
for moving said welding bar able to move it with a reciprocating
movement to press the edges of said bag against a counter bar, so
as to achieve heat welding of the edges of the bag.
11. A machine according to claim 10, characterized in that said
welding bar comprises an electrical resistance and is mounted so as
to be able to slide vertically on the basic body by means of
vertical pins which engage in respective bushings formed in the
basic body, said pins providing the supply contacts of the
electrical resistance.
12. A machine according to claim 10, characterized in that said
counter bar is mounted on a bridge structure integral with the base
body.
13. A machine according to claim 10, characterized in that said
means for moving said welding bar comprise a geared motor which
rotates a cam comprising a vertical pin which engages in a
transverse recess of a slide which provides at least one horizontal
pin that engages in at least one cam slot formed on said welding
bar.
14. A machine according to claim 13, characterized in that said air
input means comprise an air valve operated by said means for moving
the welding bar and mounted in a wall of the basic body to
introduce air into said chamber from the outside.
15. A machine according to claim 1, characterized in that said
basic body and said cover are made of plastic material.
Description
[0001] The present invention refers to a machine for vacuum packing
products in plastic bags and rigid containers, particularly for
preserving foodstuffs and perishable materials in general under
vacuum.
[0002] As is known, almost all foodstuffs, whether they be solid,
semi-solid or liquid, tend to deteriorate rapidly when they are in
contact with air, following aggression of the components contained
therein, particularly oxygen.
[0003] "Oxidation" of foodstuffs can be avoided by resorting to
vacuum storage thereof.
[0004] Although suction devices for creating vacuum in containers
exist, this method of preserving foodstuffs is not very widespread
among domestic consumers because of the drawbacks of the suction
system, which will now be briefly illustrated.
[0005] First of all, known suction devices are very expensive,
bulky and heavy, so they must form fixed installations, at least
during use. These apparatus are in fact fixed to the wall or
disposed on a flat surface and are connected to the valve of the
container in which the vacuum is to be created by means of a
flexible tube. As far as the inside structure of said apparatus is
concerned, they have: either an electric motor, on the output shaft
of which is a cam which directly drives the piston of a suction
pump or types of rotary blade pumps. Both solutions require a
rather high power and therefore over-sizing of the entire
device.
[0006] These problems of size and cost are solved by known devices
for the creation of vacuum in rigid containers. Said devices
comprise a shell consisting of a portable handgrip inside which is
housed a suction pump driven by a motor through a reduction unit.
The extreme miniaturization of the motor and suction pump assembly
leads to unsatisfactory results and an excessively long time for
creation of vacuum.
[0007] The same type of device is used for the creation of a vacuum
in plastic bags. In this case, after having cut a plastic bag and
filled it with the material to be vacuum packed, the end edges of
the bag are closed in a special machine to which a device for
creating a vacuum is applied. Consequently this machine also gives
unsatisfactory results and takes a long time to create a
vacuum.
[0008] Moreover, the method for creating a vacuum in plastic bags
by suction, requires that at least one of the walls of the bag be
made with an embossed film, so that when the open edge of the bag
is closed in the suction chamber of the machine, between two
opposite gaskets, there is not a complete seal between the inner
surfaces of the bag walls, which would prevent air suction, but
rather channels are created though-which air can leave the bag.
[0009] Furthermore embossing is a process which, besides stiffening
the sheet material and thus making it less suitable for the
purpose, increases the final costs of packaging.
[0010] The object of the present invention is to provide a machine
for vacuum packing in plastic bags and rigid containers, which
ensures high performance and short times for creation of vacuum and
which at the same time occupies little space, is cheap, practical
and simple to make.
[0011] This object is achieved in accordance with the invention
with the characteristics listed in appended independent claim
1.
[0012] Advantageous embodiments of the invention are apparent from
the dependent claims.
[0013] The machine for vacuum packing in plastic bags and rigid
containers according to the invention has a box-type shell
consisting of a base and a cover forming a chamber in which a bag
in which a vacuum is to be created is placed. A seating to
accommodate a suction pump for creation of the vacuum, driven by a
motor, is provided in the walls of said box.
[0014] Said pump is connected by means of a flexible tube to a
device in the form of a handgrip, positioned in a seat on the
outside of the box-type shell. Said device has a suction nozzle
which can be inserted in a valve provided in the outer wall of the
box-type shell and communicating with the inner chamber
thereof.
[0015] In this manner, when the suction pump is operated, a vacuum
is created in said chamber and consequently also in the bag
contained therein. Once the air contained inside the chamber and
consequently inside the bag has been evacuated, that is when the
desired level of vacuum has been reached, a slide is operated by
means of a cam which pushes the resistance bar upward for heat
sealing of the edges of the bag.
[0016] Simultaneously with the movement of the slide, the cam
actuates opening of an air valve which introduces air from the
outside into the vacuum chamber. The chamber is thus brought to
atmospheric pressure to allow subsequent opening of the cover by
the user. The heat seal previously carried out on the edges of the
bag prevents the outside air from re-entering the bag, and thus the
pressure difference that has been created between the inside of the
bag and the outside atmosphere causes flattening or shrinkage of
the bag around its contents.
[0017] The handgrip device can be extracted from its seat and the
suction nozzle can be fitted into the valve of rigid containers in
which a vacuum must be created.
[0018] It must be considered that the entire structure of the
machine according to the invention is made of thermoplastic resin,
with the consequent advantage of being extremely light and
cheap.
[0019] Moreover, the fact that a special housing is provided for
the motor and the suction pump for creation of vacuum has enabled
the reduction units of the motor to be developed in an optimal
manner to exploit greater power, which makes it possible to achieve
satisfactory conditions and short times to reach a vacuum, without
thereby increasing wear on the structural parts of the suction
pump.
[0020] Moreover, the fact that the bag is housed in an inner
chamber of the machine in which vacuum is created, makes it
possible to use any type of bag, even without embossing. In fact
the bag which is contained inside the chamber of the machine is
emptied of air from its mouth, irrespective of the configuration of
the sheet material from which it is made.
[0021] Another advantage of the machine according to the invention
is that it can be used indifferently to create a vacuum both in
plastic bags and in rigid containers.
[0022] Further characteristics of the invention will be made
clearer by the detailed description that follows, referring to a
purely exemplary and therefore non-limiting embodiment, illustrated
in the appended drawings, in which:
[0023] FIG. 1 is an axonometric exploded view of the machine for
vacuum packing in plastic bags and rigid containers according to
the invention;
[0024] FIG. 2 is a longitudinal sectional view of the machine in
FIG. 1 assembled, showing a bag therein with material to be vacuum
packed;
[0025] FIG. 2a is an enlarged sectional view of the detail enclosed
in the circle a of FIG. 2;
[0026] FIG. 3 is a cross sectional view along sectional plane
III-III of FIG. 2;
[0027] FIG. 4 is an axonometric view of the machine according to
the invention shown assembled and open, during creation of a vacuum
in a rigid container;
[0028] FIG. 5 is an axonometric exploded view of the components
making up the heat sealing device for bags forming part of the
machine according to the invention;
[0029] FIG. 6 is a broken off sectional view taken in the
longitudinal direction of the machine and illustrating the heat
welding device of FIG. 5 assembled;
[0030] FIG. 7 is a cross sectional view of the heat welding device
along sectional plane VII-VII of FIG. 6;
[0031] FIG. 8 is an enlarged longitudinal sectional view of apart
of the machine according to the invention, schematically
illustrating the air flow during the work cycle of the machine;
[0032] FIG. 9 is an axonometric exploded view of a pump for
creating vacuum of the machine, according to the invention;
[0033] FIG. 10 is a sectional view of the pump for the creation of
vacuum shown in FIG. 9.
[0034] With reference to said figures, a machine according to the
invention has been indicated as a whole with reference numeral 1.
It essentially comprises a base body 2 and a cover 3 which can be
raised by rotation around a rear hinge axis.
[0035] As shown in FIGS. 1 and 2, an inner wall 2A of the base body
2 defines a chamber 4 wherein is housed a bag 26 having the
material 27 to be vacuum packed inside it.
[0036] The chamber 4 is tightly closed when the cover 3 is in the
lowered position. The cover 3 presses on a special gasket 5 housed
in a seat in the upper part of the base or basic body 2. As shown
in FIG. 2a, the gasket 5 is made in a loop with a lip-shaped
section to compensate for errors in planarity of the cover 3 and of
the upper part of the basic body 2, due to assembly tolerances.
[0037] A housing 7, separate from the chamber 4, is provided in the
front part of the basic body 2. The following elements are located
in the housing 7:
[0038] an electrical transformer 10 to transform the electrical
current coming from the power supply into an electrical current
able to supply the electrical devices of the machine;
[0039] a suction pump 33 operated by a relative drive motor M to
create vacuum;
[0040] a tube winding device 12 consisting of a spring-loaded reel
to wind a tube 36 connected respectively to the suction pump 33 and
to a device 35 in the form of a handgrip for creating the
vacuum;
[0041] a geared motor 8 to operate a device for heat sealing the
edges 25 of the bag 26 to be vacuum packed.
[0042] As shown in FIGS. 5-7, the geared motor 8 rotates a cam 16
positioned in a seat 2B in the upper part of the basic body 2. The
cam 16 is insulated from the chamber 4 by means of an airtight
gasket 6, mounted around the shaft of the geared motor 8.
[0043] The cam 16 has a vertical pin 11 that acts in a transverse
recess 9 (directed in the longitudinal direction of the machine) of
a slide 18. In this manner rotation of the cam 16 causes a
translation of the slide 18 with a reciprocating movement
obligatorily in the direction x of FIG. 5.
[0044] A resistance holding bar 19 free to slide vertically is
mounted on the slide 18. For this purpose the resistance holding
bar 19 has two vertical pins 17 which can slide vertically inside
respective bushings 20 formed in the seat 2B.
[0045] Two horizontally disposed pins 46 are mounted on the slide
18 and engage in respective slots 30, with a cam profile, formed in
the resistance holding bar 19. The slots 30 generate an obligatory
course for the horizontal pins 46 of the slide 18. In this manner
the horizontal translating movement of the pins 46 integral with
the slide 18 cause a vertical translating movement of the
resistance holding bar 19 in the direction z in FIG. 5.
[0046] An electrical resistance 28 kept taught by means of clips 31
disposed at the outer sides of the resistance holding bar is
mounted on the resistance holding bar 19. Springs 32 disposed in
special seats inside the resistance holding bar 19 press on the
clips 31.
[0047] The bushings 20, besides acting as guides, conduct
low-voltage current to the electrical resistance 28 which extends
for the entire length of the resistance holding bar 19. When the
electrical current passes through the electrical resistance 28, the
resistance overheats, reaching an optimal temperature to cause heat
sealing of the edges of bags made of heat-weldable plastic
material.
[0048] Rotation of the cam 16 causes horizontal translation of the
slide 18 and thus raising of the resistance holding bar 19, which
is pushed against a metal bar or counter-bar 22. The metal bar 22
is locked in a bridge structure 21 integral with the basic body 2.
The bridge structure 21 packs the entire heat welding system to the
basic body 2.
[0049] The metal bar 22 is situated at a short distance above the
resistance holding bar 19. The metal bar 22 is coated with a soft
coating 23, for example silicone rubber, which ensures an adequate
resistance at the high temperatures reached by the resistance 28 on
the resistance holding bar 19. Said coating 23 allows any errors of
planarity between the two edges 25 of the bag 26 which must be
welded to be compensated for.
[0050] As shown in FIGS. 6 and 8, the cam 16 situated in the seat
2B of the upper part of the base body 2 has the task, at the end of
the welding cycle, of operating an air valve 13 for input of air
from the outside into the chamber 4. The air valve shutter in fact
obstructs an opening communicating with the chamber 4. Moreover,
the air valve 13 operates a switch 15 (FIG. 7) which controls the
start and end of the work cycle of the machine.
[0051] As shown in FIGS. 1 and 4, in the upper part of the housing
7 a seat 34 is formed which receives a device 35, in the shape of a
handgrip, connected by means of a small tube 36 to a suction outlet
69 of the pump 33. The small tube 36 is wound by means of the tube
winding device 12.
[0052] As shown in FIG. 4 vacuum can be created in rigid or
substantially rigid containers 37 by means of the device 35' by
positioning the suction nozzle 38 thereof on the valve 39 of the
container lid 37.
[0053] As shown in FIG. 2, a connector 40 accessible from the
outside and communicating with the chamber 4 is provided in the
seat 34. To be precise, the connector 40 is connected to a tube 41
which passes through the housing 7 and ends in an opening 42 formed
in the seat 2B and communicating with the chamber 4. In this
manner, when the nozzle 38 of the device 35 is engaged in the
connector 40, a vacuum can be created in the chamber 4.
[0054] As an alternative to the connector 40, a flow deflector
which switches the suction output 69 of the pump 33 between the
tube 36 directed to the device 35 and the tube 41 directed to the
opening 42 of the chamber 4 can be provided. In this manner, to
create a vacuum in the chamber 4, use of the handgrip device 35 and
the tube winder 12 is avoided.
[0055] As shown in FIG. 4, in the front part of the basic body 2,
next to the seat 43, a multi-position selector switch 44 that can
be operated by the user to select the level of vacuum desired is
provided. The switch 44 acts on a manostat 45 (FIG. 1) able to
maintain the pressure, or rather the vacuum, in the chamber 4 at
the level selected by the user.
[0056] As shown in FIG. 2, downstream of heat welding, a stop 47 is
provided on the basic body which acts as a reference for correct
positioning of the end edges 25 of the bag 26.
[0057] As shown in FIG. 4, switches 29 sensitive to lowering of the
cover 3 are provided in the base body 2, below the cover 3. Said
switches send a control signal to enable start-up of the suction
pump 33.
[0058] In the case of use of the handgrip 35 to create a vacuum in
rigid containers 37, the suction pump start-up control is provided
with a switch 43 (FIGS. 2 and 4) situated beneath the seat 34. This
switch 43, when freed by the handgrip 35, gives out an electrical
signal toward the pump 33 to set it in operation. In this manner,
to control operation of the suction pump 33, it is not necessary to
act on the cover 3 to activate the pump start-up switches 29.
[0059] Operation of the machine 1 according to the invention will
now be described.
[0060] First of all, the bag 26 is filled with the material 27 to
be vacuum packed. The cover 3 is then opened and the bag 26 is
positioned in the chamber 4.
[0061] The end edges 25 of the bag 26 must be situated in the gap
between the resistance bar 19 and the coating 23 of the metal bar
22. To ensure correct positioning of the edges of the bag, these
edges are placed up against the stop 47.
[0062] The desired level of vacuum is selected by means of the
multi-position switch 44.
[0063] Ensuring that the nozzle 38 of the device 35 is situated in
the connector 40, the cover 30 is closed to operate the pump 33.
That is to say that by pressing the cover 3 for some seconds, the
switch 29 start-up suction of the pump 33. The air is sucked from
the chamber 4 and from the bag 26 and, following the arrows F1 and
F2 (FIG. 8), exits through the opening 42. Consequently a vacuum is
created in the chamber 4 and in the bag 26.
[0064] When a satisfactory level of vacuum has been reached, a
control signal is sent to the geared motor 8 which rotates the cam
16 which in turn makes the slide 18 to translate horizontally.
During the stroke of the slide 18, the two pins 17 thereof,
following the cam slots 30 of the resistance holding bar 19 cause
raising of the resistance holding bar 19.
[0065] The resistance holding bar 19 presses against the metal bar
22 and its coating 23, squeezing the two edges 25 of the bag 26.
The resistance 28 of the resistance bar 19 causes heating of the
edges 25 of the bag 26 and thus heat welding thereof.
[0066] Rotation of the cam 16 also causes shifting of the air valve
13. Following this shifting the air valve 13 opens the opening 48
formed in the seat 2B of the base body 2 which separates the
housing 7 from the chamber 4.
[0067] Consequently, air is let into the chamber 4 from the air
valve 13, in the direction of the arrows F3. This air let into the
chamber 4 causes pressure on the outer surface of the bag 26,
allowing the inner surfaces of the walls of the bag 26 to adhere to
each other. Moreover the air let into the chamber 4 by the air
valve 13 re-establishes the atmospheric pressure in the chamber 4
and thus allows the user to raise the cover 3 when the process of
sealing the edges of the bag has been completed.
[0068] Said process will be completed when the cam 16, on turning,
gives impulse to the switch 15, which causes the start and end of
the cycle.
[0069] At this point the user can open the cover 3 and remove the
package ready for storage.
[0070] With reference to FIGS. 9 and 10, a possible suction pump
for use in the machine 1 according to the invention will now be
described.
[0071] As can be seen in the figures, the pump 33 comprises two
pistons 51 and 52, sliding counter to each other in respective
cylindrical chambers 53, 54, so that while one sucks in air, the
other expels the air previously sucked in, thus allowing continuous
operation.
[0072] The two pistons 51 and 52 are carried by respective
connecting rods 55, 56, operated by respective cans 57 and 58,
disposed in a pull-push fashion on a first common shaft 59. The
shaft 59 carries a first gear wheel 60 meshing with a second gear
wheel 61 with a smaller diameter, carried by a second shaft 62. The
second shaft 62 carries a third gear wheel 63 with a larger
diameter than the second gear wheel 61. The third gear wheel 63
meshes with a pinion 64 splined to the drive shaft 65 of the motor
M.
[0073] The suction holes 67 and 68 of the two cylinders 53 and 54
communicate with a duct 69 which is put into communication with the
suction device 35 by means of the tube 36. The exhaust holes 70 and
71 of the two cylinders 53 and 54, on the other hand, are outwardly
open (FIG. 9).
[0074] Alternatively, the suction duct 69 can be connected directly
to the chamber 4 in which the vacuum has to be created. In this
case a flow switch which can divert the output of the suction duct
69 toward the tube 36 when the device 35 is to be used to create a
vacuum in rigid containers will be provided.
[0075] The inside and outside walls of the basic body 2 and of the
cover 3 of the machine 1 are preferably made of moulded
thermoplastic resins. Special studies on the structural
configuration of the parts of the machine 1 have made it possible
to use plastic as the material, despite the chamber 4 of the
machine 1 being subject to high vacuums during creation of the
vacuum.
[0076] The use of plastic has allowed a considerable saving on the
materials and on the production process of the parts of the machine
1. Moreover the machine 1 is extremely light and easy to transport,
therefore particularly suitable for domestic use.
[0077] Numerous changes and modifications of detail known to a
person skilled in the art can be made to the present embodiment of
the invention, without departing from the scope of the invention
set forth in the appended claims.
* * * * *