Title: Incremental seal wire activation
Abstract: A method and apparatus for incremental seal wire activation, in one embodiment, is a method of sealing a seam of a bag. The method includes sealing a first side of the seam utilizing a first configuration. The method farther includes vacuuming gases from the bag. The method also includes sensing a vacuum condition responsive to vacuuming the bag. The method further includes shifting to a second configuration. The method also includes sealing a second side of the seam utilizing the second configuration.
Patent Number: 6,933,470 Issued on 08/23/2005 to Baptista
| Inventors:
|
Baptista; Alexandre A. N. (Dublin, CA)
|
| Assignee:
|
Tilia International, Inc. (San Francisco, CA)
|
| Appl. No.:
|
628028 |
| Filed:
|
July 24, 2003 |
| Current U.S. Class: |
219/243; 219/221; 338/92; 338/97 |
| Intern'l Class: |
H05B 003/02 |
| Field of Search: |
219/243,221,541,477,480
156/499
200/500,501,82.R
377/12
338/200,154,155,157,92,96,97,202,DIG.1
|
References Cited [Referenced By]
U.S. Patent Documents
| 1143579 | Jun., 1915 | Denhard.
| |
| 2749686 | Jun., 1956 | Lorenz et al.
| |
| 2899786 | May., 1959 | Harker.
| |
| 3038283 | Jun., 1962 | Unger.
| |
| 3148269 | Sep., 1964 | Van Hartesveldt et al.
| |
| 4549387 | Oct., 1985 | Marshall et al.
| |
| 4631512 | Dec., 1986 | Hishiki et al.
| |
| 4641482 | Feb., 1987 | Metz.
| |
| 5352323 | Oct., 1994 | Chi.
| |
| 5712553 | Jan., 1998 | Hallberg.
| |
| 5825974 | Oct., 1998 | Hutton et al.
| |
| 6124558 | Sep., 2000 | Baumeister et al.
| |
Primary Examiner: Walberg; Teresa J.
Attorney, Agent or Firm: Perkins Coie LLP
Claims
1. An apparatus using a first voltage terminal and a second voltage terminal, comprising:
a first electrode coupled to the first voltage terminal;
a second electrode coupled to the second voltage terminal;
a heating strip having a first end and a second end, the first end coupled to
the first voltage terminal, the second end coupled to the second voltage terminal;
wherein the first electrode is selectively connectable to the heating strip at
a first intermediate contact, the first intermediate contact of the heating strip
disposed between the first end and the second end; and
wherein the second electrode is selectively connectable to the heating strip
at a second intermediate contact, the second intermediate contact of the heating
strip disposed between the first intermediate contact and the second end.
2. The apparatus of claim 1, further comprising:
a swing arm having a first end and a second end, the first end of the swing arm
connected to the first electrode, the second end of the swing arm connected to
the second electrode.
3. The apparatus of claim 2, further comprising:
a stepper motor coupled to a midpoint of the swing arm.
4. The apparatus of claim 2, further comprising:
a gear coupled to the swing arm at a midpoint of the swing arm.
5. The apparatus of claim 4, further comprising:
a plunger having a set of teeth on a first side of the plunger, teeth of the
set of teeth enmeshed with teeth of the gear.
6. The apparatus of claim 5, further comprising:
a housing surrounding a first end of the plunger, the housing having a first
opening and a second opening, the plunger extending out of the first opening, the
second opening coupled to a vacuum trough.
7. The apparatus of claim 6, further comprising:
a pinion connected to a center of the gear at a first end of the pinion, the
pinion further connected to the midpoint of the swing arm at a second end of the
pinion; and
a mounting arm having a hole, the pinion inserted in the whole, the mounting
arm disposed between the gear and the swing arm.
8. The apparatus of claim 7, further comprising:
a weight coupled to the swing arm at a point of the swing arm between the first
end of the swing arm and the midpoint of the swing arm.
9. The apparatus of claim 8, further comprising:
a spring disposed between the swing arm and the weight.
10. The apparatus of claim 7, further comprising:
a container housing having therein a chamber, the chamber including the gear,
the pinion, the plunger, the swing arm, the first electrode and the second electrode,
the container housing having a receptacle on an interior wall of the container
housing; and
a spring connected to the swing arm at a point of the swing arm between the first
end of the swing arm and the midpoint of the swing arm, the spring further connected
to the receptable of the container housing.
11. The apparatus of claim 10, wherein:
the first voltage terminal provides a zero volt potential and the second voltage
terminal provides a ten volt potential.
12. The apparatus of claim 1, wherein:
the first voltage terminal provides a zero volt potential and the second voltage
terminal provides a ten volt potential.
13. The apparatus of claim 1, further comprising:
a first switch connected to the first electrode and connected to the first intermediate
contact, the first switch disposed between the first electrode and the first intermediate
contact; and
a second switch connected to the second electrode and connected to the second
intermediate contact, the second switch disposed between the second electrode and
the second intermediate contact.
14. The apparatus of claim 13, further comprising:
a controller coupled to a control terminal of the first switch and coupled to
a control terminal of the second switch.
15. The apparatus of claim 14, further comprising:
a vacuum sensor coupled to the controller.
16. The apparatus of claim 10, further comprising:
a vacuum pump coupled to the vacuum trough;
a controller coupled to the vacuum pump; and
a thermistor coupled to the controller.
17. The apparatus of claim 10, further comprising:
a vacuum pump coupled to the vacuum trough; and
a timing circuit coupled to the vacuum pump.
18. The apparatus of claim 5, further comprising:
a manually operated control coupled to the plunger.
19. The apparatus of claim 10, further comprising:
a transformer coupled to the first voltage terminal and the second voltage terminal;
and
a manually operated control coupled to the transformer.
20. The apparatus of claim 15, further comprising:
a thermal sensor coupled to the controller and coupled to the heating strip.
21. The apparatus of claim 15, further comprising:
a timing circuit coupled to the controller.
22. The apparatus of claim 14, further comprising:
a manually operated activation component coupled to the controller.
23. The apparatus of claim 15, further comprising:
a timer embodied in the controller.
24. The apparatus of claim 23, further comprising:
an oscillator coupled to the controller.
25. A method of sealing a seam of a bag, comprising:
sealing a first side of the seam utilizing a first configuration;
vacuuming gases from the bag;
sensing a vacuum condition responsive to the vacuuming the bag;
shifting to a second configuration; and
sealing a second side of the seam utilizing the second configuration.
26. The method of claim 25, further comprising:
sensing a non-vacuum condition; and
shifting from the second configuration to the first configuration.
27. The method of claim 26, further comprising:
initializing in the first configuration.
28. The method of claim 26, wherein:
the first side is a left side; and the second side is a right side.
29. The method of claim 26, wherein:
shifting to the second configuration includes disconnecting a first electrode
from a seal wire and connecting a second electrode to the seal wire.
30. The method of claim 26, wherein:
shifting to the second configuration includes decoupling a first electrode from
a seal wire and coupling a second electrode to the seal wire.
31. The method of claim 30, wherein:
shifting to the first configuration includes coupling a first electrode to the
seal wire and decoupling a second electrode from the seal wire.
32. The method of claim 29, wherein:
shifting to the first configuration includes connecting a first electrode to
the seal wire and disconnecting a second electrode from the seal wire.
33. The method of claim 32, wherein:
shifting to the first configuration includes moving a plunger responsive to the
vacuum condition, and rotating a gear coupled to the plunger, the gear further
coupled to the first electrode and the second electrode.
34. The method of claim 33, wherein:
shifting to the second configuration includes rotating the gear responsive to
the non-vacuum condition and moving the plunger.
35. The method of claim 25, further comprising:
timing the sealing the first side, the vacuuming occuring responsive to the timing.
36. The method of claim 35, further comprising:
timing the sealing the second side; and
stopping the sealing the second side responsive to the timing.
37. The method of claim 25, further comprising:
sensing a temperature associated with sealing the first side; and
the vacuuming occuring responsive to the sensing.
38. The method of claim 25, further comprising:
sensing a temperature associated with sealing the first side.
39. The method of claim 25, wherein:
the method progresses responsive to manually generated control signals.
40. The method of claim 25, wherein:
shifting to the second configuration occurs responsive to a manually generated
control signal.
41. An apparatus, comprising:
means for sealing a first portion of a plastic bag and a second portion of a
plastic bag;
first means for activating the means for sealing for the first portion;
second means for activating the means for scaling for the second portion; and
means for switching between the first means for activating and the second means
for activating.
42. An apparatus for sealing a plastic bag, comprising:
a power source having a high voltage terminal and a low voltage terminal;
a container housing having therein a chamber, the power source disposed within
the chamber, the container housing further having a vacuum channel, the vacuum
channel having a first receptacle and a second receptable;
a vacuum pump disposed within the chamber;
a tube having a first end connected to the vacuum pump and a second end connected
to the first receptacle of the vacuum channel;
a first electrode coupled to the low voltage terminal;
a second electrode coupled to the high voltage terminal;
a heating strip mounted on a surface of the container housing, the heating strip
having a first end and a second end, the first end coupled to the low voltage terminal,
the second end coupled to the high voltage terminal;
wherein the first electrode is selectively connectable to the heating strip at
a first intermediate contact, the first intermediate contact of the heating strip
disposed between the first end and the second end; and
wherein the second electrode is selectively connectable to the heating strip
at a second intermediate contact, the second intermediate contact of the heating
strip disposed between the first intermediate contact and the second end.
43. The apparatus of claim 42, further comprising:
a swing arm having a first end and a second end, the first end of the swing arm
connected to the first electrode, the second end of the swing arm connected to
the second electrode.
44. The apparatus of claim 43, further comprising:
a gear coupled to the swing arm at a midpoint of the swing arm.
45. The apparatus of claim 44, further comprising:
a plunger having a set of teeth on a first side of the plunger, teeth of the
set of teeth enmeshed with teeth of the gear.
46. The apparatus of claim 45, further comprising:
a housing surrounding a first end of the plunger, the housing having a first
opening and a second opening, the plunger extending out of the first opening, the
second opening coupled to the second receptacle of the vacuum channel.
47. The apparatus of claim 46, further comprising:
a pinion connected to a center of the gear at a first end of the pinion, the
pinion further connected to the midpoint of the swing arm at a second end of the
pinion; and
a mounting arm having a hole, the pinion inserted in the whole, the mounting
arm disposed between the gear and the swing arm, the mounting arm mounted on an
inner surface of the chamber of the container housing.
48. The apparatus of claim 47, further comprising:
a spring connected to the swing arm at a point of the swing arm between the first
end of the swing arm and the midpoint of the swing arm, the spring further connected
to a receptable of the chamber.
49. The apparatus of claim 42, wherein:
the low voltage terminal provides a zero volt potential and the high voltage
terminal provides a ten volt potential.
50. The apparatus of claim 48, wherein:
the low voltage terminal provides a zero volt potential and the high voltage
terminal provides a ten volt potential.
51. The apparatus of claim 42, further comprising:
a first switch connected to the first electrode and connected to the first intermediate
contact, the first switch disposed between the first electrode and the first intermediate
contact; and
a second switch connected to the second electrode and connected to the second
intermediate contact, the second switch disposed between the second electrode and
the second intermediate contact.
52. The apparatus of claim 51, further comprising:
a controller coupled to a control terminal of the first switch and coupled to
a control terminal of the second switch.
53. The apparatus of claim 52, further comprising:
a vacuum sensor coupled to the controller, the vacuum sensor coupled to the second
receptacle of the vacuum channel.
54. The apparatus of claim 42, wherein:
the power source is a transformer.
55. The apparatus of claim 53, wherein:
the power source is a transformer.
56. The apparatus of claim 55, wherein:
the controller is coupled to the vacuum pump; and further comprising:
an oscillator coupled to the controller.
57. In a packaging machine, an apparatus for selective application of electric
voltage to a first voltage reception point and a second voltage reception point,
using a first voltage terminal and a second voltage terminal, comprising:
a first electrode coupled to the first voltage terminal;
a second electrode coupled to the second voltage terminal;
wherein the first electrode is selectively connectable to the first voltage reception
point; and
wherein the second electrode is selectively connectable to the second voltage
reception point.
58. The apparatus of claim 57, wherein:
the first voltage reception point and the second voltage reception point are
located at intermediate locations of a sealing strip.
59. The apparatus of claim 57, further comprising:
a swing arm having a first end and a second end, the first end of the swing arm
connected to the first electrode, the second end of the swing arm connected to
the second electrode.
60. The apparatus of claim 59, further comprising:
a gear coupled to the swing arm at a midpoint of the swing arm.
61. The apparatus of claim 60, further comprising:
a plunger having a set of teeth on a first side of the plunger, teeth of the
set of teeth enmeshed with teeth of the gear.
62. The apparatus of claim 61, further comprising:
a housing surrounding a first end of the plunger, the housing having a first
opening and a second opening, the plunger extending out of the first opening, the
second opening coupled to a vacuum trough.
63. The apparatus of claim 62, further comprising:
a pinion connected to a center of the gear at a first end of the pinion, the
pinion further connected to the midpoint of the swing arm at a second end of the
pinion; and
a mounting arm having a hole, the pinion inserted in the whole, the mounting
arm disposed between the gear and the swing arm.
64. The apparatus of claim 63, further comprising:
a container housing having therein a chamber, the chamber including the gear,
the pinion, the plunger, the swing arm, the first electrode and the second electrode,
the container housing having a receptacle on an interior wall of the container
housing; and
a spring connected to the swing arm at a point of the swing arm between the first
end of the swing arm and the midpoint of the swing arm, the spring further connected
to the receptable of the container housing.
65. The apparatus of claim 64, wherein:
the first voltage terminal provides a zero volt potential and the second voltage
terminal provides a ten volt potential.
66. The apparatus of claim 57, wherein:
the first voltage terminal provides a zero volt potential and the second voltage
terminal provides a ten volt potential.
67. The apparatus of claim 57, further comprising:
a first switch connected to the first electrode and connected to the first voltage
reception point, the first switch disposed between the first electrode and the
first voltage reception point; and
a second switch connected to the second electrode and connected to the second
voltage reception point, the second switch disposed between the second electrode
and the second voltage reception point.
68. The apparatus of claim 67, further comprising:
a controller coupled to a control terminal of the first switch and coupled to
a control terminal of the second switch.
69. A method of sealing a seam of a bag, comprising:
vacuuming gases from the bag;
sealing a first portion of the seam utilizing a first configuration after material
to be enclosed has been placed in the bag;
shifting to a second configuration; and
sealing a second portion of the seam utilizing the second configuration.
70. The method of claim 69, further comprising:
sensing a non-vacuum condition; and
shifting from the second configuration to the first configuration.
71. The method of claim 70, further comprising:
initializing in the first configuration.
72. The method of claim 71, wherein:
the first portion is a left side; and the second portion is a right side.
73. The method of claim 71, wherein:
shifting to the second configuration includes disconnecting a first electrode
from a seal wire and connecting a second electrode to the seal wire.
74. The method of claim 71, wherein:
shifting to the second configuration includes decoupling a first electrode from
a seal wire and coupling a second electrode to the seal wire.
75. The method of claim 74, wherein:
shifting to the first configuration includes coupling a first electrode to the
seal wire and decoupling a second electrode from the seal wire.
76. The method of claim 73, wherein:
shifting to the first configuration includes connecting a first electrode to
the seal wire and disconnecting a second electrode from the seal wire.
77. The method of claim 76, wherein:
shifting to the second configuration further includes timing the sealing the
first side until a first predetermined time limit is reached.
78. The method of claim 77, wherein:
shifting to the first configuration further includes timing the sealing the second
side until a second predetermined time limit is reached.
Description
FIELD
The present invention relates to the field of heating circuitry. More particularly,
the present invention relates to heat sealing of plastic for consumer and industrial applications.
BACKGROUND
Consumer products involving vacuuming and sealing plastic bags have grown
in popularity over the years. The basic model available includes a seal wire which
seals the length of the bag and a vacuum pump which pumps air out of the bag prior
to sealing. This model works well enough to have sold and inspired imitation.
Unfortunately, the model described requires use of expensive components
and still suffers from air bubbles in some vacuum-sealed packages. In particular,
the seal wire used to seal the plastic is heated throughout its entire length at
one time, requiring a high current for activation, and a correspondingly big and
expensive transformer. Moreover, the larger the area to be heated, the longer the
heating process is likely to take. Similarly, the vacuum must be maintained over
a wide physical area (the length of the bag) and may increase the time needed to
seal due to any cold air flowing over the area to be sealed.
Transformers in particular are well-known as expensive components, and
their cost increases in a nonlinear fashion, such that a first transformer with
twice the capacity of a second transformer may cost much more than twice the price
of the second transformer. Similarly, the bigger the cross-section through which
vacuum must be maintained, the larger (and more costly) the pump must be to maintain
that vacuum.
Accordingly, it may be preferable to implement a system in which relatively
low-cost components may be used to ease the requirements for a large transformer
and a large vacuum pump.
SUMMARY
An apparatus and method for incremental seal wire activation or incremental sealing
in a sealing unit is described and illustrated. In various embodiments, the invention
typically includes a method of vacuum-sealing an item such as a plastic bag by
sealing a first portion of the bag, vacuuming the bag, and sealing a second portion
of the bag under vacuum. The first portion and second portion may have some overlap,
such that a part of the bag sealed as part of the first portion may undergo further
sealing activity as part of the second portion. Moreover, the sizes and relative
locations of the first portion and second portion may be adjustable.
Alternately, the invention typically includes a first selective electrical
connection useful for electrifying a first portion of a heat-sealing strip, a second
selective electrical connection useful for electrifying a second portion of a heat-sealing
strip, a vacuum pump, and a controller which controls the other components. The
controller may be a simple mechanical controller or an integrated circuit for example.
In one embodiment, the invention is an apparatus using a first voltage terminal
and a second voltage terminal. The apparatus includes a first electrode coupled
to the first voltage terminal. The apparatus also includes a second electrode coupled
to the second voltage terminal. The apparatus further includes a heating strip
having a first end and a second end, the first end coupled to the first voltage
terminal, and the second end coupled to the second voltage terminal. The first
electrode is selectively connectable to the heating strip at a first intermediate
contact, with the first intermediate contact of the heating strip disposed between
the first end and the second end. The second electrode is selectively connectable
to the heating strip at a second intermediate contact, with the second intermediate
contact of the heating strip disposed between the first intermediate contact and
the second end.
In an alternate embodiment, the invention is a method of sealing a seam of a
bag.
The method includes sealing a first side of the seam utilizing a first configuration.
The method further includes vacuuming gases from the bag. The method also includes
sensing a vacuum condition responsive to vacuuming the bag. The method further
includes shifting to a second configuration. The method also includes sealing a
second side of the seam utilizing the second configuration.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates an embodiment of an apparatus for incremental sealing in
a first configuration.
FIG. 1B illustrates an embodiment of an apparatus for incremental sealing in
a second configuration.
FIG. 2 illustrates an embodiment of an apparatus for incremental sealing in
schematic form.
FIG. 3A illustrates an embodiment of a method of incremental sealing.
FIG. 3B illustrates an embodiment of one method of incremental sealing.
FIG. 3C illustrates an alternative embodiment of a method of incremental sealing.
FIG. 4 illustrates another alternative embodiment of a method of incremental sealing.
FIG. 5A illustrates an alternate embodiment of an apparatus for incremental sealing.
FIG. 5B illustrates the alternate embodiment of an apparatus for incremental
sealing in a first configuration.
FIG. 5C illustrates the alternate embodiment of an apparatus for incremental
sealing in a second configuration.
FIG. 6 illustrates an overall apparatus including an embodiment of an apparatus
for incremental sealing.
FIG. 7 illustrates yet another alternative embodiment of an apparatus for incremental sealing.
DETAILED DESCRIPTION
An apparatus and method for incremental seal wire activation or incremental sealing
in a sealing unit is described and illustrated. The apparatus and method may be
used to activate a first portion of a seal wire, then to activate a second portion
of a seal wire thereby allowing for fully sealing a plastic bag or other similar container.
In the following description, for purposes of explanation, numerous specific
details
are set forth in order to provide a thorough understanding of the invention. It
will be apparent, however, to one skilled in the art that the invention can be
practiced without these specific details. In other instances, structures and devices
are shown in block diagram form in order to avoid obscuring the invention.
In various embodiments, the invention typically includes a method of vacuum-sealing
an item such as a plastic bag by sealing a first portion of the bag, vacuuming
the bag, and sealing a second portion of the bag under vacuum. The first portion
and second portion may have some overlap, such that a part of the bag sealed as
part of the first portion may undergo further sealing activity as part of the second
portion. Moreover, the sizes and relative locations of the first portion and second
portion may be adjustable.
Alternately, the invention typically includes a first selective electrical
connection useful for electrifying a first portion of a heat-sealing strip, a second
selective electrical connection useful for electrifying a second portion of a heat-sealing
strip, a vacuum pump, and a controller which controls the other components. The
controller may be a simple mechanical controller or an integrated circuit for example.
In one embodiment, the invention is an apparatus using a first voltage terminal
and a second voltage terminal. The apparatus includes a first electrode coupled
to the first voltage terminal. The apparatus also includes a second electrode coupled
to the second voltage terminal. The apparatus further includes a heating strip
having a first end and a second end, the first end coupled to the first voltage
terminal, and the second end coupled to the second voltage terminal. The first
electrode is selectively connectable to the heating strip at a first intermediate
contact, with the first intermediate contact of the heating strip disposed between
the first end and the second end. The second electrode is selectively connectable
to the heating strip at a second intermediate contact, with the second intermediate
contact of the heating strip disposed between the first intermediate contact and
the second end.
In an alternate embodiment, the invention is a method of sealing a seam of a
bag.
The method includes sealing a first side of the seam utilizing a first configuration.
The method further includes vacuuming gases from the bag. The method also includes
sensing a vacuum condition responsive to vacuuming the bag. The method further
includes shifting to a second configuration. The method also includes sealing a
second side of the seam utilizing the second configuration.
In one embodiment the method of incremental sealing involves first activating
a first portion of a seal wire, then vacuuming ambient air out of an associated
plastic bag, then activating the second portion of the seal wire. In an alternate
embodiment an apparatus for incremental sealing includes a first electrode and
a second electrode both of which are selectively connected to a heating strip and
further includes the heating strip which is at one end coupled to a first voltage
terminal and at the second end coupled to a second voltage terminal. The first
electrode is selectively connectable to the heating strip at a first intermediate
contact. The first intermediate contact of the heating strip is disposed between
the first end and the second end. The second electrode is also selectively connectable
to the heating strip at a second intermediate contact. The second intermediate
contact of the heating strip is disposed between the first intermediate contact
and the second end. The present invention provides for the opportunity to seal
a first part of the bag, then vacuum out the atmosphere, thereby, potentially achieving
a more effective vacuum, and then seal the second part of the bag under vacuum.
The present invention potentially allows for use of a smaller or a less current
consuming transformer and for use of less maximum current to activate sealing of
the plastic bag that is typically used with these devices.
As is illustrated in FIGS. 1A and 1B, one embodiment of the apparatus may have
a first configuration and a second configuration. The first configuration is illustrated
in FIG.
1A. Sealing wire
100 has coupled at one end a 0 volt power
terminal at point
110 and at another end a 10 volt power terminal at point
120. The 0 volt and 10 volt power terminals may be two terminals of a single
power source or supply, for example, and the specific magnitudes of the voltages
are exemplary and illustrative of a specific design choice rather than a requirement
of the invention.
At an intermediate point
180 electrode
140 is selectively connected
to the sealing wire
100. Electrode
140 is set at 10 volts, through
coupling to the 10 volt power terminal. As a result, the portion of sealing wire
100 between point
110 and intermediate point
180 is hot whereas
the portion of sealing wire
100 between intermediate point
180 and
point
120 is left relatively unheated due to the lack of voltage differential
between those two points. Electrode
130 is set at 0 volts and is illustrated
as disconnected from sealing wire
100.
Turning to FIG. 1B, intermediate point
190 illustrates the connection
point where electrode
130 is selectively connected to sealing wire
100.
This generates a hot zone between intermediate point
190 and point
120
due to the voltage differential between those two points. The area between point
110 and intermediate point
190 is left unheated. Note that intermediate
points
180 and
190 may be referred to as voltage reception points,
where a predetermined voltage is applied to a component such as sealing wire
100.
The embodiment illustrated in FIGS. 1A and 1B may be implemented as part of a
larger embodiment illustrated in FIG.
2. The embodiment of an apparatus
for incremental sealing illustrated in FIG. 2 includes the two electrodes as described
and further includes a mechanism for switching from having one electrode connected
to having the electrode connected and a mechanism for sensing whether vacuum is
present in the associated vacuum trough of a typical sealing apparatus. Electrode
230 is coupled to swing arm
205 via fastener
210 at one end
(or a first end) of swing arm
205. At a second end of swing arm
205
is electrode
240, which is coupled to swing arm
205 through fastener
215. At the midpoint of swing arm
205 pinion
220 is inserted
in a through hole of swing arm
205. Pinion
220 passes through mounting
bracket
250 and on the other side is connected to gear
235, such
that when gear
235 turns, swing arm
205 rotates and each of electrodes
230 and
240 are moved.
Gear
235 meshes with the teeth of plunger
245. The first end of
plunger
245 includes rubber-sealing ring
265, both of which are inserted
into housing
260. Housing
260 may be an annular housing with a large
opening on a first end in which the first end of plunger
245 is inserted
and a narrow opening on a second end to which hose
270 is connected. Hose
270 is also connected to the vacuum trough of the associated apparatus.
Thus, when vacuum is present in the vacuum trough of the associated apparatus,
suction through hose
270 draws plunger
245 further into housing
260,
thus turning gear
235. Moreover, when air fills the vacuum of the associated
vacuum trough, this eases suction against plunger
245, allowing swing arm
205 to return to its normal position. At through hole
285, spring
255 is connected to swing arm
205 and spring
255 is also connected
to receptacle
275, which is an attachment on the housing of the associated
apparatus. The tension in spring
255 naturally will cause swing arm
205
to return to a position where electrode
240 is in contact with the associated
sealing wire absent an opposing force (such as the vacuum pulling plunger
245).
In some embodiments, it may be useful to control the amount of time during which
heating occurs. This can be achieved in a variety of ways. For example, a thermistor
or other heat sensing component may be employed to determine when a seal wire or
nearby component has reached a predetermined temperature. This determination may
either signal heating is complete or that a timer should be started to allow for
fusing at a predetermined temperature for a predetermined amount of time. In alternate
embodiments, a timer may be employed to cause heating of a sealing strip for a
predetermined amount of time without monitoring of an associated temperature. In
other alternate embodiments, a microcontroller may implement timing functions or
similar functions and processes for control of heating. Moreover, in yet other
alternate embodiments, user activation (such as by pushing or pushing and holding
a button for example) may be used to initiate and maintain heating.
While the apparatuses illustrated in FIGS. 1A,
1B and
2 can be
used for incremental sealing the method of sealing incrementally may also be utilized.
FIG. 3A illustrates one embodiment of a method of incremental sealing. At block
310 the process is initialized typically by using a first configuration
or first state in which a portion of the sealing may occur. At block
320
the first side of the object is sealed. At block
330 vacuum is induced,
pulling air out of whatever object is to be sealed. At block
340 this vacuum
is sensed. At block
350 responsive to sensing vacuum, a configuration switch
occurs such that a second configuration or state is used. At block
360 in
the second configuration the second side of the object to be sealed is sealed under
vacuum. At block
370 the absence of vacuum is sensed (after the vacuum is
filled) and at block
380 the apparatus in question switches back to its
original configuration or state.
This method may be further understood with reference to specific embodiments
of the method. For example the embodiment of FIG. 3B is related to utilization
of shifting electrodes. At block
310a the process is initialized
and a first configuration or first state of the apparatus in question is used,
with a first electrode connected and a second electrode disconnected. At block
320 the left side of the material to be sealed is sealed. At block
330
vacuum is induced. At block
340 the induced vacuum of block
330 is
sensed. At block
350a the electrodes are switched from the first
configuration to the second configuration, with the first electrode disconnected
and the second electrode connected. As a result at block
360 the right side
of the material to be sealed is sealed. At block
370 the absence of vacuum
is then sensed and at block
380a the configuration is switched back
to the original or first configuration.
Similarly, FIG. 3C illustrates a method related to use of switches. At
block
310b the method is initialized typically with a first switch
closed and a second switch open in what may be referred to as a first configuration.
At block
320 the left side is sealed utilizing current passing through the
first switch. At block
330 vacuum is switched on. At block
340 the
vacuum of block
330 is sensed. At block
350b a change in configurations
occurs, such that switch one is switched off and then switch two is switched on
in a break-before-make type of transition. At block
360 the right side is
then sealed. At block
370 the lack of vacuum is then sensed and at block
380b the method switches back to the first configuration where switch
two is off and switch one is on. As indicated with respect to FIG. 3C alternate
embodiments of the apparatus may be used.
Still another alternate embodiment of a method may be employed. FIG. 4 illustrates
an alternate embodiment of a method of incremental seal activation. In the method
illustrated, all sealing occurs under vacuum conditions, and the sealing processes
are timed based on predetermined time limits. At block
405, the process
is initialized, with associated sealing apparatus in a first configuration or state.
At block
415, vacuum is initiated or pumped down. At block
425, sealing
of a first side or first portion of an object to be sealed is commenced. At block
435, the sealing of block
425 is timed until a predetermined time
limit is reached. Block
435, in various alternate embodiments, may be replaced
with a sensing block wherein deactivation of a seal command (pushbutton for example)
from a user is sensed, or with a sensing block wherein a temperature is sensed,
resulting in either termination of the sealing or timing of the sealing to a predetermined
time limit.
At block
445, the method includes switching from the first configuration
or state to a second configuration or state. At block
455, sealing of the
second side or portion (using the second configuration or state) initiates. At
block
465, the sealing of block
455 is timed until a predetermined
time limit is reached. Block
465 is susceptible to alternative implementations
in a similar manner to block
435. At block
475, vacuum pumping stops,
after the heating process is expected to have achieved its goals. At block
485,
the method involves switching back to an original or first configuration or state.
In FIG. 5A, an alternate embodiment using power MOSFETS is illustrated. Seal
wire
500 has a 0 volt connection at endpoint
510 and at a second endpoint
520 a 10 volt connection. Switch
530 is a power MOSFET which is coupled
to a 0 volt potential, thereby allowing selective connection of that 0 volt potential
to an intermediate point of seal wire
500. Similarly, switch
540
is connected to a second intermediate point of seal wire
500 and is coupled
to a 10 volt potential terminal, thereby allowing for a selective connection of
that 10 volt potential to an intermediate point of seal wire
500.
FIG. 5B illustrates a first configuration of the alternate embodiment of an
apparatus such as that of FIG.
5A. In this instance, switch
540 is
closed thereby connecting or allowing the 10 volt potential to be present at the
first intermediate point of seal wire
500. Switch
530 is open, thereby
allowing for selective connection or disconnection with the 0 volt potential at
the second intermediate point of seal wire
500.
Similarly, FIG. 5C illustrates the second configuration of the alternate
embodiment in which switch
530 is closed and switch
540 is open thereby
allowing for connection of the 0 volt potential to seal wire
500 at the
second intermediate point and selective disconnection of the 10 volt potential.
Turning to FIG. 6, an overall system or apparatus in which various embodiments
of the invention may be used is illustrated. In particular, FIG. 6 illustrates
the original first apparatus embodiment in a larger system. Apparatus
600
includes the embodiment of FIG. 1 or a similar embodiment along with additional
components. Swing arm
605 is coupled at one end through pinion
610
to electrode
630 and at a second end through pinion
615 to electrode
640. A pinion at roughly the center point of swing arm
605, pinion
620, goes through a through hole and supports
650 to gear
635.
Support
650 is directly connected to the interior wall of a chamber within
device
600 in which all of this material is housed. Thus, gear
635,
swing arm
605 and electrodes
630 and
640 are all supported
from device
600. Moreover, when gear
635 rotates, swing arm
605
also rotates. Also connected to swing arm
605 at through hole
685
is spring
655, which is further connected to receptacle
675 of device
600. Spring
655 effectively causes tension to hold in place swing
arm
605 in a first configuration.
Meshed with teeth of gear
635 are teeth of plunger
645. Plunger
645 also has an annular disk
665 such as a rubber ring, both of which
are inserted into housing
660 thus providing a relatively sealed connection
thereto. Housing
660 has a first end into which plunger
645 is inserted
and a second end around which tube
670 is affixed. Tube
670 is further
affixed to a first receptacle of vacuum trough
687. Vacuum trough
687
has a second receptacle to which is affixed a second tube
690 which goes
to a vacuum pump. Thus, when the pump pumps down to vacuum through tube
690,
vacuum trough
687 then effectively pumps air out of tube
670 and
plunger
645 is pulled toward the interior of housing
660 thus, causing
gear
635 to rotate. When the vacuum is filled in vacuum trough
687,
plunger
645 then is naturally moved away by the tension in spring
655
and the resulting rotation of swing arm
605 and gear
635 resets to
the first configuration. All of this results in at most one of electrodes
630
and
640 connecting to seal wire
650 at any given time. One end of
seal wire
650 is connected to a ground potential, as is electrode
630.
The second end of seal wire
650 is connected to a 10 volt potential, as
is electrode
640.
Turning to FIG. 7, yet another alternate embodiment of an incremental seal
wire apparatus is illustrated. Swing arm
700 is coupled at one end to electrode
730 through a pinion and at another end to electrode
740 through
another pinion. At a middle point swing arm
700 is coupled through yet another
pinion or axle to stepper motor
705. Stepper motor
705 may then be
activated to turn swing arm
700 the appropriate fractional number of steps
to switch from a first configuration with electrode
730 connected to a seal
wire, to a second configuration with electrode
740 connected to the seal wire.
From the foregoing, it will be appreciated that specific embodiments of the
invention have been described herein for purposes of illustration, but that various
modifications may be made without deviating from the spirit and scope of the invention.
In some instances, reference has been made to characteristics likely to be present
in various or some embodiments, but these characteristics are also not necessarily
limiting on the spirit and scope of the invention. In the illustrations and description,
structures have been provided which may be formed or assembled in other ways within
the spirit and scope of the invention. Similarly, methods have been illustrated
and described as linear processes, but such methods may have operations reordered
or implemented in parallel within the spirit and scope of the invention. Accordingly,
the invention is not limited except as by the appended claims.
*
