Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02383430 2002-04-24
1
METHOD AND APPARATUS FOR MAKING A KNOT WITH
FLEXIBLE MATERIAL WRAPPED AROUND AN ARTICLE
FIELD OF THE INVENTION
The present invention is concerned with a method and an apparatus
for making a knot with two end portions of flexible material wrapped around
an article.
BACKGROUND OF THE INVENTION
It is well known in the art that articles or products are wrapped with
stretched film and that nothing else is required other than a brush to wipe
the last tail. When stretched film is used, the static generated as it is
stretched and the tacky material added to one side of the film make the tail
stick to the layer previously applied. This method is appropriate when the
article is shipped in a closed trailer or container but is inadequate when the
product is shipped on an open trailer or stored outside because the tails are
prone to getting loose as they are exposed to wind or bad weather.
In other applications, the articles are wrapped and then the tails are
heat-sealed to previously applied layers of film. This well known technology
is very popular. The seal is achieved by heating a heat pad which is
brought in contact with the tail and previously applied layers of film. The
film
then melts in order to bond layers together. However, this method has
some limitations. When the heat is applied to the film layers to create
melting, holes can be created through all layers which rei-nove the water
proof protection of the product and/or can damage the product.
CA 02383430 2002-04-24
2
Known in the art, there is the U.S. patent no. 4 223,516, naming as
inventor Marc G. VANSTEELANT, wherein there is described a knotter
primarily for use with a crop baling machine. This knotter includes a
rotatable twine holder for gripping the primary and secondary portions of
twine and holding them in a side-by-side relationship extending along a
predetermined path. A rotatable billhook is mounted adjacent to the twine
holder and positioned to intersect the predetermined path. Drive means
interconnecting the twine holder and billhook rotate the two elements in
timed relation such that during a first cycle of the billhook the twine
portions
are positioned thereabout, and during a second cycle of the billhook a knot
is tied therein.
Also known in the art, there is the U.S. patent no. 5,240,295 naming
as inventor Donald R. SPENCER, wherein there is described a device
which facilitates tying knots, particularly blood knots joining sections of a
leader for a fishing line. The device includes a flexible frame having a base
and left and right legs which project away from the base, there being a gap
between the two legs. The frame carries a post which projects from the
base into the gap intermediate the two legs and may be extended or
retracted and even withdrawn. The legs carry winders which rotate about a
common axis. Each winder has a hollow interior, a winding arm located at
the gap, and a gripping sleeve remote from the gap. Lines or lengths of
leader are inserted through the hollow interior of each winder and engaged
with the winder arm of the other winder. When the winders are rotated, their
arms twist the lines around each other, but the post forms a separation or
opening in the wound region of the lines. The tag ends of the lines are
inserted through the separation to produce a blood knot which is pulled
tight.
CA 02383430 2002-04-24
3
Also known in the art, there is the U.S. patent 5,088,270 naming as
inventor Werner K. DlEHL, wherein there is described a heat seal assembly
and method for securing stretch-film wrapped about a package, which
assembly grasps and aligns two strips of roped film wraps, heats adjacent
faces of the roped film sections and thereafter compresses these heated
faces to weld them to each other and secure the film wrap about the
package.
Also known in the art, there is the U.S. patent no. 6,195,968 naming
Yanick MAROIS et a!. as inventors, wherein there is described an apparatus
for wrapping a load with a flexible wrapping material which prevents the
flexible material from unwrapping itself after the load has been wrapped.
The apparatus includes a first finger and a gripper for positioning a portion
of a first rope supplied by the supplying means at a predetermined location.
Once the load has been wrapped, a second finger and a guide wheel are
provided to position a portion of a second rope supplied by the supply
means at the predetermined position. The first and second ropes are
fastened together at the predetermined position, and a portion of the second
rope is cut downstream of the predetermined position.
Also known in the art, there are the following U.S. patents which
describe different apparatuses and methods for making a knot: 3,570,553;
3,752,517; 3,915,483; 4,420,177; 4,765,082; 4,795,201; 4,872,240;
5,197,217; 5,236,232; 5,728,109; 5,787,691; 5,802,810; 5,878,555;
5,971,447; and 6,143,006.
A drawback with systems or methods of the prior art is that none of
them is concerned with a method of making a knot with two end portions of
flexible material wrapped around an article in a simple and efficient manner.
CA 02383430 2002-04-24
4
An object of the present invention is to provide a method and an
apparatus for making a knot with two end portions of flexible material
wrapped around an article in a manner that is simpler and more efficient
than those provided in prior art.
It is also an object of the present invention to provide an apparatus
and a method for making a knot with two end portions of f1exible material
wrapped around an article in an automated manner so that the apparatus
and method can be applied to successive articles without any manual
intervention of an operator.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a method of
making a knot with first and second rope-shaped end portions of flexible
material wrapped around an article, comprising steps of: (a) guiding the end
portions along a predetermined path; (b) (i) nipping the first end portion at
a
first point of the predetermined path, (ii) nipping the second end portion at
a
second point of the predetermined path, and (iii) nipping the second end
portion at a third point of the predetermined path; (c) cutting the second end
portion between the second and third points to obtain a free end thereof; (d)
moving the end portions to obtain a loop; (e) releasing the first end portion
from the guiding of step (a) to obtain a free end thereof; and (f) inserting
the
free ends into the loop to form and tighten the knot.
According to the present invention, there is also provided an
apparatus for making a knot with first and second rope-shaped end portions
of flexible material wrapped around an article, comprising: a controllable
holder for holding a free end of the first end portion; controllable guides
for
guiding the end portions along a predetermined path; first controllable
CA 02383430 2002-04-24
nippers for nipping the first end portion at a first point of the
predetermined
path; second controllable nippers for nipping the second end portion at a
second point of the predetermined path; third controllable nippers for
nipping the second end portion at a third point of the predetermined path; a
5 controllable cutter for cutting the second end portion between the second
and third points to obtain a free end thereof; first controllable moving means
for moving the end portions to obtain a loop; and second controllable
moving means for moving the free ends into the loop to form and tighten the
knot.
The objects, advantages and other features of the present invention
will become more apparent upon reading of the following non-restrictive
description of preferred embodiments thereof, given for the purpose of
exemplification only with reference to the accompanying drawings,
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view of a wrapping machine provided with a
first preferred embodiment of the present invention;
figure 2 is a partial perspective view of the wrapping machine
provided with the first preferred embodiment according to the present
invention in a first operating position;
figure 3 is a partial perspective view of the wrapping machine
provided with the first preferred embodiment according to the present
invention in a second operating position;
CA 02383430 2002-04-24
6
figure 4 is a partial perspective view of the wrapping machine
provided with the first preferred embodiment according to the present
invention in a third operating position;
figure 5 is a perspective view of an element of the first preferred
embodiment in a first operating position;
figure 6 is a perspective view of the element shown in figure 5 in a
second operating position, in relation with the wrapped article;
figure 7 is a perspective view of the element shown in figures 5 an 6
in a third operating position, in relation with the wrapped article;
figure 8 is a general perspective view of another element of the first
preferred embodiment ;
figure 9 is a perspective view of the element shown in figure 8 in an
operating position, in relation with the rope-shaped end portions of flexible
material;
figure 10 is a perspective view of the element shown in figure 9 in a
different operating position;
figure 11 is a perspective view of the element shown in figures 9 and
10 in a different operating position;
figure 12 is a perspective view of the element shown in figures 9 to
11 in a different operating position;
figure 13 is an enlarged view of a detail of figure 12;
CA 02383430 2002-04-24
..
7
figure 14 is a perspective view of the element shown in figures 9 to
13 in a different operating position;
figure 15 is a perspective view of the element shown in figures 9 to
14 in a different operating position;
figure 16 is a perspective view of the element shown in figures 9 to
in a different operating position;
figure 17 is a perspective view of the element shown in figures 9 to
16 in a different operating position;
figure 18 is a perspective view of the element shown in figures 9 to
17 in a different operating position;
figure 19 is a perspective view of the element shown in figures 9 to
18 in a different operating position;
figure 20 is a perspective view of the element shown in figures 9 to
19 in a different operating position;
figure 21 is a perspective view of the element shown in figures 9 to
20 in a different operating position;
figure 22 is a perspective view of the element shown in figures 9 to
21 in a different operating position;
figure 23 is a perspective view of the element shown in figures 9 to
22 in a different operating position;
CA 02383430 2002-04-24
8
figure 24 is a perspective view of a second preferred embodiment of
the present invention;
figure 25 is a schematic representation of a first step of a method
according to the first and second preferred embodiments;
figure 26 is a schematic representation of a second step of the
method initiated in figure 25;
figure 27 is a schematic representation of a third step of the method
initiated in figures 25 and 26;
figure 28 is a schematic representation of a fourth step of the method
initiated in figures 25 to 27;
figure 29 is a perspective view of a wrapping machine provided with a
third preferred embodiment of the present invention;
figure 30 is a top view of the wrapping machine with the third
preferred embodiment without the article, in an operating position;
figure 31 is a top view of the wrapping machine with the third
preferred embodiment with the article, in a different operating position;
figure 32 is a top view of the wrapping machine with the third
preferred embodiment, with the article, in a different operating position;
figure 33 is a top view of the wrapping machine with the third
preferred embodiment, with the article, in a different operating position;
CA 02383430 2002-04-24
.
9
figure 34 is a partial top view of the third preferred embodiment, with
the article, in a different operating position;
figure 35 is a partial top view of the third preferred embodiment, with
the article, in a different operating position;
figure 36 is a partial top view of the third preferred embodiment, with
the article, in a different operating position;
figure 37 is a partial top view of the third preferred enibodiment, with
the article, in a different operating position;
figure 38 is a partial top view of the third preferred embodiment, with
the article, in a different operation position;
figure 39 is a perspective view of the third preferred embodiment;
figure 40 is a partial perspective view of the third preferred
embodiment where certain elements thereof have been removed;
figure 41 is a top view of the third preferred embodiment;
figure 42 is a side view of the third preferred embodiment where
certain elements thereof have been removed;
figure 43 is a front view of the third preferred embodiment;
figure 44 is a perspective view of the third preferred embodiment in a
first operating position;
CA 02383430 2002-04-24
figure 45 is a perspective of the third preferred embodiment in a
second operating position;
5 figure 46 is a perspective view of the third preferred embodiment in a
third operating position;
figure 47 is a perspective view of the third preferred embodiment in a
fourth operating position;
figure 48 is a perspective view of third preferred embodiment in a fifth
operating position;
figure 49 is a perspective view of the third preferred embodiment in a
sixth operating position;
figure 50 is a schematic view of the rope-shaped end portions to be
knotted according to the third preferred embodiment, in a first operating
position;
figure 51 is a schematic view of the rope-shaped end portions to be
knotted according to the third preferred embodiment, in a second operating
position;
figure 52 is a schematic view of the rope-shaped end portions to be
knotted according to the third preferred embodiment, in a third operating
position;
CA 02383430 2002-04-24
11
figure 53 is a schematic view of the rope-shaped end portions to be
knotted according to the third preferred embodiment, in a fourth operating
position;
figure 54 is a schematic view of the rope-shaped end portions to be
knotted according to the third preferred embodiment, in a fifth operating
position; and
figure 55 is a schematic view of the remaining rope-shaped end
portion once the knot has been completed according to the third preferred
embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to figures 1 to 23, there is shown a first preferred
embodiment of an apparatus according to the present invention within the
environment in which it operates. Please find hereunder the numeral list of
the components illustrated in figures 1 to 23:
1. Vertical boom 15. Actuator
2. Film delivering carriage 16. Right groove-shaped stop
3. Roping assembly 17. Tilt arm right
4. Knotter assembly 18. Pivot plate
6. Conveyor 19. Idler sprocket
7. Rotary arm 20. Main plate
8. Frame 21. Linear guide
9. Article 22. Actuator
10. Film roll 23. Crowder jib
11. First end portion 24. Tilt arm left
12. Second end portion 25. Cam follower
CA 02383430 2002-04-24
12
26. Chain 64. Swivel arm
27. Left groove-shaped stop 65. Shouldered sleeve
28. Chain connector 66. Tapered sleeve
29. Tension screw 67. Fixed jaw
30. Left linear bearing 68. Movable jaw
31. Right linear bearing 69. Finger
32. Cam follower 70. Roller
33. Idler sprocket 71. Main table
50. Motor 72. Movable jaw
51. Rotary actuator 73. Tail gripper mounting base
53. Cut wire fork 75. Proximity sensor
54. Wire tension spring 76. Bias shoulder
55. Wire holder 77. Fixed jaw
56. Top clamp jaw 78. Mounting plate
57. Bottom clamp jaw 80. Conveyor mounting angle member
58. Clamp assembly plate 81. Tail gripper actuator
59. Cut wire 85. Tail puller actuator
60. Actuator 88. Second rope
61. Clamp actuator 90. Pinion bevel gear
62. Cut wire actuator 92. Tail gripper actuator
63. Leveling leg 94. Home proximity sensor
The apparatus is for making a knot with first and second rope-shaped
end portions 11 and 12 of flexible material 10 wrapped around an article 9.
The first preferred embodiment comprises a controllable holder for holding
the free end of the first end portion. Preferably, the holder consists of a
gripper comprising first and second jaws 57 and 56. The second jaw 56 is
movable with respect to the first jaw 57 between a first position where the
second jaw 56 operatively rests against the first jaw 57 as shown for
example in figure 9 and a second position where the second jaw 56 is away
CA 02383430 2002-04-24
.
13
from the first jaw 57 as shown for example in figure 14. The gripper also
comprises an actuating element which is a top clamp jaw actuator 60
connected to the second jaw 56 for moving it between its first and second
positions.
The apparatus also comprises controllable guides for guiding the end
portions 11 and 12 along a predetermined path as shown for example in
figure 3. Preferably, the controllable guides comprise a groove-shaped
element formed by the first and second jaws 57 and 56 when said second
jaw 56 is in its first position to, on the one hand, grip the free end of the
first
end portion 11 and, on the other hand, guide the second end portion 12
extending between the article 9 and the film delivering carriage 2 as shown
for example in figure 3. Preferably, the controllable guides also comprise
two groove-shaped stops 16 and 27 movable between a first position where
the stops are distal from each other as shown in figure 5 and a second
position where the stops 16 and 27 are adjacent as shown in figure 7 to
guide the end portions 11 and 12 extending between jaws 57 and 56 and
the article 9 as shown in figures 3 and 7, thereby defining the predetermined
path between the jaws 57 and 56 and the stops 16 and 27. The groove-
shaped stops 16 and 27 are mounted on a conveyor side 6 as shown in
figure 1.
The apparatus also comprises first controllable nippers for nipping
the first end portion at a point of the predetermined path, and second
controllable nippers for nipping the second end portion at a second point of
the predetermined path. Preferably, the first and second nippers are made
of an assembly. The assembly comprises first and second jaws. The first
jaw is a cylindrical element made of a tapered sleeve 66. The second jaw is
a finger 69 movable between a first position where an end thereof
operatively rests against the tapered sleeve 66 as shown for example in
CA 02383430 2002-04-24
14
figures 12 and 13 and a second position where the end thereof is away from
the tapered sleeve 66 as shown for example in figure 8.
The assembly also comprises moving means for moving the finger 69
between its first and second positions. The moving means comprise first
and second cooperating members. The first member is a main table 71
having a cavity with a peripheral wall. The second member is at least
partially mounted within the peripheral wall of the cavity and rotatable
thereabout. The second member is a shouldered sleeve 65 having a guiding
groove for guiding the finger 69 along a radial direction with respect to the
tapered sleeve 66. The shouldered sleeve 65 includes a pin connected to
the finger 69, a roller 70 connected to the pin and a resilient element for
urging the finger 69 towards its second position. The finger 69 is pushed
away from its second position towards its first position against the resilient
member by a rotational movement of the shouldered sleeve 65 with respect
to the main table 71 upon a pressure exerted by the peripheral wall on the
finger 69 via the pin and the roller 70.
The apparatus according to the first preferred embodiment also
comprises third controllable nippers for nipping the second end portion at a
third point of the predetermined path. Preferably, these third nippers are
embodied by the gripper which is made of the jaws 57 and 56.
The apparatus according to the first preferred embodiment also
comprises a controllable cutter for cutting the second end portion 12
between the second and third points of the predetermined path to obtain a
free end thereof. Preferably, the controllable cutter is a heated wire cutter.
An actuator 62 is connected to the controllable cutter for moving the cut wire
59 of the cutter between a first position where the cut wire 59 is in position
for cutting the second end portion 12 and a second position where the cut
CA 02383430 2002-04-24
wire 59 is in a position remote from the second end portion. The cut wire 59
is a heated cut wire. Heat wire is a well known technology.
The shouldered sleeve 65 and the main table 71 are provided with a
5 central opening as shown for example in figure 9. The tapered sleeve is
mounted within the central opening of the shouldered sleeve 65 and the
main table 71. The tapered sleeve 66 further comprise an actuator 85 for
moving the tapered sleeve 66 between a first position where the tapered
sleeve 66 projects from the central opening in position for cooperating with
10 the finger 69 and a second position where the tapered sleeve 66 is
retracted
from the central opening as shown for example in figures 9 and 10.
Further more, the shouldered sleeve 65 has an upper surface
provided with a straight off center groove that crosses said upper surface
15 from one side thereof to the other via a peripheral portion of the central
opening. The off-center groove is sized for receiving the rope-shaped end
portions. The off-center groove is provided, along a portion thereof
extending from the central opening to the periphery of the upper surface,
with a bias shoulder 76. The assembly further comprises an actuator 15 for
moving the shouldered sleeve 65, main table 71 and the tapered sleeve 66
between a first position where the off-center groove of the shouldered
sleeve 65 is lower than pre-determined path of the rope-shaped end 11 and
12 and a second position where the off-center groove of the shouldered
sleeve 65 is adjacent to the pre-determined path of the rope-shaped end 11
and 12 as shown for example in figure 10 and 11.
The apparatus according to the first preferred embodiment also
comprises controllable moving means for moving the rope-shaped end
portions to obtain a loop. Preferably, these first moving means are
embodied by the assembly. The loop is obtained by rotating the shouldered
CA 02383430 2002-04-24
. = .
16
sleeve 65 with respect to tapered sleeve 66 when the shouldered sleeve 65
and the main table 71 are in their first position as shown in figure 16
thereby
looping the free ends around the tapered sleeve 66. Preferably, the tapered
sleeve 66 is hollow with an open end.
The apparatus according to the first preferred embodiment also
comprises moving means for moving the free ends of the end portions 11
and 12 into the loop to form and tighten the knot. Preferably, these moving
means comprise pair of jaws 72 and 71 movable between a first position
where it is in position to grip the free ends of the rope-shaped end portions
11 and 12 once the looping thereof around the tapered sleeve 66 has been
performed to a second position where a part of the free ends faces the open
end of the tapered sleeve 66 as shown for example in figure 18. Preferably,
these moving means also comprise pair of jaws 67 and 68. The jaw 68 is
movable between a first position where the jaws 67 and 68 are in position to
receive the free ends 11 and 12 facing the open end of the tapered sleeve
66 and a second position where the free end are griped with jaws 67 and 68
as shown in figures 18 and 19. The jaws 67 and 68 further comprise an
actuator 85 for moving the jaws 67 and 68 to a first position where the jaws
project from the central opening of the tapered sleeve 66 and a second
position where the jaws are retracted from the 'central opening of the
tapered sleeve 66 in order to insert the free ends into the loop as shown for
example in figures 19, 20 and 21.
Once form, the knot is tightened using the movement of the
shouldered sleeve 65, the main table 71 and the tapered sleeve 66
previously described.
We will now describe a method for making a knot with the first and
second rope-shaped end portions 11 and 12 of flexible material wrapped
CA 02383430 2002-04-24
17
around the article 9 in reference to figures 3 and 12 to 21. The method
comprises the steps of (a) guiding the end portions 11 and 12 along a
predetermined path as shown in figure 3; (b) (i) nipping the first end portion
11 at a first point of the predetermined path as shown in figures 12 and 13,
(ii) nipping the second end portion 12 at a second point of the
predetermined path as shown in figures 12 and 13, and (iii) nipping the
second end portion 12 at a third point of the predetermined path as shown
in figures 14 and 15; (c) cutting the second end portion 12 between the
second and third points to obtain a free end thereof as shown in figure 15;
(d) moving the end portions 11 and 12 to obtain a loop as shown in figure
16; (e) releasing the first end portion 11 from the guiding of step (a) to
obtain a free end thereof as shown in figure 14; and (f) inserting the free
ends into the loop to form and tighten the knot as shown in figures 17 to 21.
Preferably, according to the first preferred embodiment, step (e) is
performed after sub-steps (i) and (ii) and before sub-steps (iii). Also
preferably, step (d) is performed after step (c) and comprises steps of
rotating the free ends around a hollow shaft having an end opening to obtain
the loop as shown in figure 16. Step (f) comprises (iv) gripping and moving
the free ends to place portions thereof over the end opening as shown in
figures 17 and 18, and (v) gripping and inserting said portions of the free
ends into the hollow shaft thereby inserting the free ends into the loop as
shown in figures 19 to 21. Also preferably, in step (a) the end portions are
guided in parallel along the predetermined path as shown in figure 3. Also
preferably, step (c) includes steps of heating a heat wire, and moving the
heat wire transversally with respect to the second end portion 12 as shown
in figure 15.
We will now describe with more details the operation of the first
preferred embodiment. At the beginning of a wrapping procedure, the first
CA 02383430 2002-04-24
18
end portion 11 of flexible material 10 is already placed within jaws 56 and
57, and the film delivering carriage 2 is in roping configuration. The
wrapping cycle is started by rotating the film delivering carriage 2 around
the
article 9 and after the first quarter of revolution of the wrapping arm 7, the
film delivering carriage 2 is brought back to full web configuration to fully
wrap the article with a web by moving the carriage 2 according to a
conventional up and down spiral motion. During its last half revolution, the
film delivering carriage 2 is once more brought into rope configuration to
form the second rope-shaped end portion 12. The arm 7 is then stopped at
its home position.
The two ropes are guided by activating the guide actuator 22. The
clamp actuator 61 is also activated in order to raise the clamp assembiy.
The arm 7 is rotated backward to position the rope 12 in relation to the
clamp jaws 56 and 57
Then the shouldered sleeve 65 with the main table 71 are brought up
to position the two end portions 11 and 12 between the tapered sleeve 66
and the finger 69, within the groove of the shouldered sleeve 65 as shown in
figure 11. The shouldered sleeve 65 is then rotated with a motor 50 and
gear 90 until the end portions 11 and 12 are locked between the tapered
sleeve 66 and the finger 69 as shown in figures 12 and 13. This operation is
controlled by counting a predetermined number of teeth on the gear 90
which is a pinion bevel gear and by means of proximity sensor 75. The
upper jaw 56 is lifted by means of actuator 60 to release the first end
portion
11 as shown in figure 14. The second end portion 12 placed between the
jaws 56 and 57 is grasped when the jaw 56 is moved down as shown in
figure 15.
CA 02383430 2002-04-24
19
The cut wire 59 is heated and the heat wire actuator 62 moves the
cut wire 59 up to cut the second end portion 12. The actuator 62 then brings
back the cut wire 59 to its down position. Another end portion 88 is then
obtained. This end portion 88 extends between the jaws 57 and 56 to the
film delivering carriage 2 and will be used as the first end portion of the
next
wrapping cycle,
The shouldered sleeve 65 is then rotated according to a
predetermined number of teeth with the motor 50 and gear 90 so as to bring
the end portions 11 and 12 in position to be gripped with the jaws 72 and 77
which are opened by means of actuator 83, as shown in figure 16. Once in
place, the actuator 83 closes the jaws 72 onto 77 to hold the end portions
11 and 12 as shown in figure 17. The rotary actuator 51 is then activated to
rotate the jaws 72 and 77 and bring the end portion 11 and 12 between the
jaws 67 and 68, as shown in figure 18. The jaws 67 and 68 are then closed
on the end portions 11 and 12 by means of the actuator 92, as shown in
figure 19. The jaws 72 and 77 are then opened by means of the actuator 83
to free the end portions 11 and 12. The end portions 11 and 12 are then
drawn downwardly by means of the actuator 85 to form the knot as shown in
figure 20. The actuator 15 is activated to lower the shouldered sleeve 65
and the main table 71 in order to tighten the knot as shown in figure 21.The
rotary actuator 51 is brought back to its home position. The jaws 67 and 68
are then opened by means of actuator 81 as shown in figure 22. The stops
16 and 27 are moved back to their standby position as shown in figure 5 by
means of actuator 22. Then the knot rests on the side of the wrapped article
9.
The shouldered sleeve 65 is rotated back to its home position as
shown in figure 23 by means of motor 50 and the home proximity sensor 94
shown in figure 19. The clamp actuator 61 is retracted to home position as
CA 02383430 2002-04-24
shown in figure 23. The product is conveyed out of the wrapping area by
activating conveyor 6. The next wrapping cycle is ready to start.
Referring now to figure 24, there is shown a second preferred
5 embodiment of the invention. A first tail of the film is placed in the
initial
clamp 111. The wrapping cycle is started with the film delivering carriage
(not shown) in roping configuration. After the first half revolution of the
delivering carriage (not shown), it is brought back to full web configuration
to
fully wrap the article. During the last half revolution of the delivering
carriage
10 around the article, the film delivering carriage is brought back into rope
configuration to make a second tail.
A gathering mechanism 105, 106 and 113 gathers the two tails and
clamps them at a predetermined position between the knotter head of the
15 apparatus and the wrapped articie. The knotter head is brought up by
means of actuator 112 to position the two tails between a knotting sleeve
107 and the cam clamp 108 within the guide 104. The knotting sleeve 107 is
then rotated with the motor and gear 102 until the two tails are locked
against the knotting sleeve 107 and the cam clamp 108 and then stopped.
The first tail which is still in the initial clamp 111, is released from it.
The second tail, which extends from the knotting sleeve 107 to the film
delivering carriage is then clamped by means of initial clamp 111. The last
tail is then cut between the initial clamp 111 and the knotting sleeve 107.
The initial clamp 111 now holds the first tail of the next cycle. The knotting
sleeve 107 performs a full revolution under the control of the motor and gear
102 to wrap a portion of the tails around the knotting sleeve 107. When the
revolution is completed, the two ends of the tails are gripped by means of
tail gripper 109. Once gripped, the rotary actuator 101 brings the tail end
portions over the wrapped knotting sleeve 107 into the jaws 103 of the tail
0
CA 02383430 2002-04-24
21
puller 110. Once the tail ends are in the tail puller jaws, the tail puller
110 is
retracting to pull the two tail ends into the core of the knotting sleeve 107.
The knotting sleeve - 107 is then pulled downward in order to release the
portion wrapped around it. The gathering clamps 105, 106 and 113 release
the rope portions. The knot is now formed between the article and the tail
puller. The tail puller releases the two tail ends and the knot is freed. All
the
mechanism then returns to the initial position and the next cycle is ready to
start.
Referring now to figures 25 and 28, there are shown the steps of the
method for forming a knot by means of first preferred embodiment shown in
figures 1 to 23, and second embodiment shown in figure 24. In figure 25, the
tails are guided along a predetermined path. Then, in figures 26 and 27, a
loop is formed. In figure 28, the free ends of the tails are pulled into the
loop
to form and tighten the knot.
Referring now to figures 29 to 54, there is shown a third preferred
embodiment of the present invention. Please find hereunder the numeral list
of the components illustrated in figures 29 to 48:
201 Tower 212 Transfer arm
202 Carriage 213 Transfer arm link
203 Film roll 214 Clamp jaw trigger
204 Article 215 Clamp push arm
205 Machine base 216 Spring cage
206 Rotary table 217 Rack
207 Table clamp 218 Transfer arm base
208 Knotter base 219 Clamp jaw
209 Knotter head 220 Pinion
211 Frame plate 221 Clamp lifter arm
CA 02383430 2002-04-24
22
222 Transfer arm trigger 255 Drive sprocket
223 Rotation head drive shaft 256 Idler sprocket
224 Clamp lifter cam 257 Drive pulley
225 Clamp rotation cam 258 Idler pulley
226 Trigger base 230 Sprocket
227 Linear bearing 231 Chain
228 Guide shaft 232 Gear motor support
229 Proximity sensor 233 Forward/reverse gear motor
234 Bracket 259 Belt
235 Cam rotation gear motor 260 Rotation head guide
236 Rotation head gear motor 261 Transfer arm pinion
237 Transfer clamp jaw 262 Heat wire
238 Clamp roller guide 263 Table clamp trigger
239 Clamp solenoid 264 First rope
240 Solenoid rod 265 Last rope
241 Transfer clamp 266 Knot
242 Rotation head 311 Frame plate
243 Movable jaw 314 Clamp jaw trigger
244 Rack pushpin guide 315 Clamp push arm
245 Rack pushpin 317 Rack
246 Cam drive shaft 320 Pinion
247 Movable jaw shaft 321 Clamp lifter arm
251 Heat wire holder 324 Clamp lifter cam
252 Transfer arm lever 325 Clamp rotation cam
253 Transfer arm cam follower 346 Cam drive shaft
254 Chain 355 Sprocket
To start a new cycle, the operator places the rope 264 delivered by
the carriage 202 into the table clamp 207 as shown in figure 30. An article
CA 02383430 2002-04-24
23
204 to be wrapped is brought up unto the rotary table 206 as shown in
figure 31. The cycle is started and the article 204 is wrapped by means of a
conventional method. During the last revolution of the table 206, the film of
the film roll 203 is turned from a web into a rope 265 by means of the
carriage 202. The table 206 is then stopped at approximately 1/8 of a turn
from its home position as shown in figures 32 to 34.
The knotter head is brought from its home position to its knotting
position, as shown for example in figure 33, by means of gear motor 233,
the linear bearing 227 and guide shaft 228 shown in figure 39. As the
knotter head is moved to its knotting position, the two ropes 264 and 265
are automatically guided in the rotation head 242, the rope 264 in the
bottom slot and the rope 265 in the top slot. The rope 264 is then clamped
by means of gear motor 235 that drives a shaft 246 on which a cam 224
produces a lifting movement via the clamp jaw 219 by means of a lifter arm
221. As the clamp jaw 219 is moved upwardly, the movable jaw 243 grips
the rope 264 as it hits clamp jaw trigger 214. The clamp motion for clamping
the rope 264 is from a down position to an up position. The rope 265 is also
clamped by means of a gear motor 235 that activates a shaft on which a
cam 324 produces a lifting movement via a clamp jaw by means of lifter
321. As the clamp jaw is moved downwardly, a movable jaw grips the rope
265 as it hits the clamp jaw trigger 314. The motion for clamping the rope
265 is from a top position to a down position. Both motions are symmetrical
and linked with a chain 254 and sprockets 255 and 355 as shown in figure
42.
The rope 265 is simultaneously clamped a second time by means of
clamp jaw 237 mounted on the transfer arm 212 by activating clamp
solenoid 239. After being clamped, the heat wire 262 is activated to cut the
rope 265 between the transfer clamp frame 241 and the clamp jaw. Then
CA 02383430 2002-04-24
24
gear motor 236 is activated to rotate the rotation head 242, After a full turn
thereof, a loop is obtained. The gear motor 235 is activated again to drive
the shafts 246 and 346 on which cams 225 and 325 are respectively
mounted. As the cams 225 and 325 are turning, a pushing motion is
produced by means of rack pushpin 245 and another rack pushpin. The
linear motion of rack pushpin 245 and the other rack pushpin is transformed
into a rotary motion by means of racks 217 and 317 and pinions 220 and
320. The rotary motion induces a rotation of push arms 215 and 315 with
clamp jaw 219 and another clamp jaw. The push arms 215 and 315 push
the two ends of the ropes 264 and 265 into the loop previously produced by
the rotation head 242.
When the rope tails are in the loop, the action of the cams 225 and
325 brings push arms 215 and 315 to their initial position leaving the tails
of
the ropes 264 and 265 into the loop. Simultaneously, the action of the cams
224 and 324 brings the clamp jaw 219 and the other clamp jaw back to their
initial position. As clamp jaw 219 and the other clamp jaw are moved back,
the ropes 264 and 265 are released from movable jaw 243 and another
movable jaw by means of springs. The knot 266 is now made and is freed
from the knotter head. All the movements are accomplished during a single
revolution of the shafts 246 and 346 and cams 224, 324, 225 and 325.
The knotter head then moves backward by means of gear motor 233.
As it is moving backward, the transfer arm cam follower 253 mounted on the
transfer arm lever 252 hits the transfer arm trigger 222. The transfer arm
trigger 222 is spring loaded to activate the transfer arm lever 252 only upon
the backward movement of the knotter head and not when it moves forward.
As it hits the transfer arm trigger 222, the transfer arm cam follower 253
follows a path that makes the transfer arm 212 move to the other side of the
knotter head as shown in figure 36. The rope 265 which is clamped by the
CA 02383430 2002-04-24
transfer clamp 241 is now pulled to the other side of the knotter head. As
the knotter head keeps moving backwards, the transfer clamp 241 extends
over the table clamp 207 and the table clamp trigger 263 opens a table
clamp movable jaw that is spring loaded. The rope 265 is simultaneously
5 engaged in the table clamp 207 and released from the transfer clamp 241
as shown in figure 37. As the backward movement of the knotter head is
completed, the transfer arm cam follower 253 leaves the transfer arm trigger
path and is brought back to its home position. The rotary table can now
complete the last 1/8 of revolution to its home position and the wrapped
10 article 204 can be removed. The rope 265 becomes the rope 264 for the
next cycle.
Referring now to figures 50 to 55, we will describe the method for
making a knot according to the third preferred embodiment. Figure 50
15 illustrates the first step where at the end of the wrapping cycle, the
first rope
264 is held by a table clamp and the second rope 265 extends between the
article and the carriage. The ropes 264 and 265 are placed in parallel to
each other. The first rope 264 is on the bottom. The knotter head is brought
forward in position and the two ropes 264 and 265 slide in their appropriate
20 slots in a rotating head.
Referring now to figure 51, there is shown step 2, where once in
position, the knotter head clamps the two ropes 264 and 265 one on each
side of the head. The second rope 265 is simultaneously clamped by the
25 transfer arm clamp and is cut between rotation head clamp and the transfer
arm.
Referring now to figure 52, there is shown step 3 where the rotation
head performs a complete revolution which produces a loop between the
two ropes 264 and 265.
CA 02383430 2002-04-24
26
Referring now to figure 53, there is shown step 4 where the clamp
push arm pushes the two free ends of the ropes 264 and 265 into the loop
as it rotates.
Referring now to figure 54, there is shown step 5 where the knotter
head clamp releases the ropes and the knotter head moves backward to its
home position.
Referring now to figure 55, there is shown step 6 where as the
knotter head moves back, the transfer arm brings the remaining rope 265
into the table clamp jaw and releases it to finish its movement to its home
position.
Although preferred embodiments of the invention have been
described in details herein and illustrated in the accompanying drawings, it
is to be understood that the invention is not limited to these precise
embodiments and that various changes and modifications may be effected
therein without departing from the scope or spirit of the invention.
