TECHNICAL FIELD
[0001] The invention relates to a method and cap feeding device for applying a cap to a
neck of a container. This type of devices comprises a conveyor, a package transport
system, a chute or cap dispenser and a gripper or cap holder for attaching or rotating
the cap on a neck of the container. Threaded caps are rotated on a threaded neck of
the container while so called push-on caps are pressed onto a non-threaded neck of
the container.
[0002] Packages of this type are generally used in connection with packages for liquid chemicals,
motor oil, hygiene products, pharmaceuticals or foodstuff, such as milk, juice, water,
yoghurt and similar, but can be used for other types of packages with or without a
threaded neck. One common type of packages of this type is plastic packages having
a neck and a cap of plastic materials.
PRIOR ART
[0003] There is a plurality of different types of devices for applying a threaded cap to
a threaded neck of a package by means of machines having grippers, in a turret or
a machine that stops movement of packages while caps are tightened. Caps are supplied
via a star wheel or from a chute. Another type of device comprises a conveyor and
a pair of package supporting belts for transporting packages in a travel direction,
wherein a cap is supplied to the top of the neck when the package passes a cap dispenser.
Then, the cap is tightened by means of a cap tightening device. For example, a line
of packages is transported on a continuously operating conveyor, wherein the continuously
conveyed packages at short intervals pass the cap dispenser and wherein caps at short
intervals are tightened by means of the cap tightening belts. The arrangements used
for obtaining caps from a dispenser or a chute and for moving caps to containers need
improvements to increase efficiency and durability.
SUMMARY OF THE INVENTION
[0004] An object of the invention is to improve prior art methods and devices for applying
a cap to a neck of a package. The invention relates to a method and cap feeding device
for applying a cap to a neck of a package or container. In various embodiments the
invention improves prior art methods and devices for applying a threaded cap to a
threaded neck of a package. A cap feeder is provided with at least one carrier to
catch the caps and feed them to a predetermined position, where grippers or cap holders
can grip or fix the caps. The number of carriers is the same as the number of caps
per process, normally one to four. The carrier is catching the caps from a chute or
a dispenser in a predetermined inclined position. The caps are fixed in the chute/dispenser
so when cap feeder is moving forward under the chute/dispenser, one cap at the time
is caught by each carrier from a predetermined inclined position.
[0005] The cap feeder then moves to a position where grippers or cap holders can grip or
hold the caps. This position is above a conveyor with packages. Packages may be provided
with threaded necks. In this position the caps are put on the packages in a handover
process. After the handover the cap feeder is returned in a parallel move to its position
behind the chute/dispenser, prepared to catch new caps.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] In order that the manner in which the above recited and other advantages and objects
of the invention are obtained will be readily understood, a more particular description
of the invention briefly described above will be rendered by reference to specific
embodiments thereof which are illustrated in the appended drawings.
[0007] Understanding that these drawings depict only typical embodiments of the invention
and are not therefore to be considered to be limiting of its scope, the invention
will be described and explained with additional specificity and detail through the
use of the accompanying drawings in which:
- Fig. 1
- is a schematic perspective view of a first embodiment of a cap feeding device in accordance
with the invention,
- Fig. 2
- is schematic top view showing a motion pattern of a cap feeder of a cap feeding device
in accordance with the invention,
- Fig. 3
- is schematic top view showing a cap feeder of a cap feeding device in accordance with
the invention in different positions during a process of catching caps and moving
them on the cap feeder,
- Fig. 4
- is schematic top view showing a cap feeder of a cap feeding device as shown in Fig.
3 in further positions during a process of moving the caps to a position where the
caps are put on packages,
- Fig. 5
- is a schematic perspective view of another embodiment of a cap feeding device in accordance
with the invention, and
- Fig. 6
- is a schematic side elevation view of the cap feeding device shown in Fig. 5.
DETAILED DESCRIPTION
[0008] In a basic embodiment of a cap feeding device 10 for applying a cap 12 to a neck
14 of a container or package 16 comprises a movable cap feeder 24 with carriers 22
as shown in Fig. 1 to Fig. 6. In various embodiments, cap feeder 24 has a flat upper
side from which at least one carrier 22 extends. Carrier 22 is circular and an outer
diameter of carrier 22 is adapted to and smaller than an inner diameter of cap 12.
As shown in Fig. 1 and Fig. 2, cap feeder 24 is rectangular and is provided with two
carriers 22 arranged along a longer side of cap feeder 24. Caps 12 and necks 14 of
container 16 can be threaded.
[0009] A chute 18 extending in an inclined direction in relation to a horizontal plane holds
a plurality of caps 12 and is provided at a lowermost end section with a cap dispenser
20 holding the lowest cap 12 in the chute 18 in an inclined position in relation to
a plane in which the cap feeder 24 is moving. In various embodiments chute is replaced
by or combined with a dispenser. Chute is used to cover different embodiments including
chute, dispenser or a combination of a chute and a dispenser. Containers 16 are transported
by a conveyor 26 moving in a substantially linear transport direction T.
[0010] Cap feeder 24 moves in a cap feeding process along a path P as indicated in Fig.
2 starting in a first position A below chute 18. During movement to a second position
B, cap feeder 24 catches a first cap 12 that is held by cap dispenser 20 in an inclined
position in relation to a horizontal plane, c.f. Fig. 6. First cap 12 is drawn from
the position in the chute 18 by a first carrier 22. After some further movement a
second cap 12 that now is lowermost is caught by a second carrier 22 on the cap feeder
24. In various embodiments, cap feeder 24 is provided with three or more carriers
22, each capable of catching one cap 12 from chute 18 at the time.
[0011] In position B, cap feeder 24 supports two caps 12. In a further movement, cap feeder
24 moves to a third position C which is over conveyor 26 with containers 16 in upright
positions with a neck in an uppermost section. In this position, or during movement
in transport direction T, a lift mechanism comprising two grippers or cap holders
32 is lowered to pick up the caps 12 on cap feeder 24. Grippers or cap holders 32
can be rotated, so as to screw caps 12 onto containers 16, or pushed down into engagement
with neck of containers 16 if caps are push-on caps. In various embodiments, lift
mechanism with grippers or cap holders 32 will move along with conveyor 26 during
this process as indicated by arrow M in Fig. 4. During movement as indicated by arrow
M grippers or cap holders 32 will be lowered until caps engage necks 14 of packages
16. Grippers or cap holders 32 can also rotate during this movement if caps 12 and
necks of containers 16 are threaded.
[0012] When grippers or cap holders 32 have removed caps 12 from cap feeder 24 it will leave
the position over conveyor 26, so as to allow grippers or cap holders 32 to be lowered
to containers 16 and move to a fourth position D. Cap feeder 24 then will move in
a direction parallel to transport direction T but displaced a first distance X in
transverse direction. First distance X of displacement is sufficient to allow grippers
or cap holders 32 to be lowered to containers 16. Cap feeder 24 then will return to
first position A to start cap feeding process over again. Cap feeder 24 is provided
with an inclined section 25 at one end. Inclined section 25 is in front when cap feeder
moves in directions parallel to transport direction T. Inclined section 25 will ensure
that cap feeder 24 does not capture a bottom most cap 12 when moving back to position
A.
[0013] Cap feeder 24 is supported by a drive mechanism 30, c.f. Fig. 5, that is arranged
to move cap feeder 24 along path P. In various embodiments, drive mechanism 30 comprises
a first linear motor 34 operating along a first bar 36 extending in a direction in
parallel with transport direction T. First linear motor 34 and first bar 36 has an
operation length sufficient to cover movement of cap feeder 24 from first position
A to second position B. First linear motor 34 is connected to a support plate 44.
Drive mechanism 30 comprises also a second linear motor 38 that will move a second
bar 40 a second distance Y in a linear movement in a direction perpendicular to transport
direction T. Second linear motor 38 is supported by support plate 44. Second bar 40
is connected to a support bar 42 of cap feeder 24. In various embodiments, cap feeder
24 is connected to second bar 40 to allow a tilting movement of cap feeder 24 in relation
to a horizontal plane as indicated by arrow R in Fig. 5.
[0014] Cap feeder 24 is connected also to two extending through bushings in two bushing
blocks 48. Support rods 46 will ensure that cap feeder 24 will move in a horizontal
plane when second linear motor 38 moves cap feeder 24. Chute 18 holds a plurality
of caps 12, a bottom most sticking out partly from chute 18 at angle a in relation
to horizontal plane. Caps 12 are all placed in chute 18 with an open end downwards
to allow carrier 22 to catch one cap when cap feeder 24 passes by. In various embodiments,
angle a is about 30 degrees or in interval 25-45 degrees.
[0015] While certain illustrative embodiments of the invention have been described in particularity,
it will be understood that various other modifications will be readily apparent to
those skilled in the art without departing from the scope and spirit of the invention.
Accordingly, it is not intended that the scope of the claims appended hereto be limited
to the description set forth herein but rather that the claims be construed as encompassing
all equivalents of the present invention which are apparent to those skilled in the
art to which the invention pertains.
1. A method of applying a cap (12) to a neck (14) of a container (16), comprising the
steps of
a) retaining a cap (12) in a position inclined in relation to a horizontal plane,
b) catching said cap (12) on a carrier (22) extending vertically from a cap feeder
(24) by moving said cap feeder (24) from a first position (A) to a second position
(B) in a horizontal plane while catching said inclined cap (12),
c) moving said cap feeder (24) supporting said cap (12) to a third position (C) over
a conveyor (26) moving in a horizontal plane in a travel direction (T) while supporting
containers (16),
d) lifting said cap (12) from cap feeder (24),
e) moving said cap feeder (24) away from the position over conveyor (26) to allow
said cap (12) to be lowered to a position engaging said neck (14) of container (16),
f) while moving along in said travel direction (T) attaching said cap (12) on said
neck (14) of container (16),
g) moving said cap feeder (24) back to said first position (A).
2. A method as claimed in claim 1, wherein caps (12) and necks (14) are threaded and
step of attaching threaded cap (12) to threaded neck (14) of container (16) comprises
rotating said threaded cap (12) on said threaded neck (14) of container (16).
3. A method as claimed in claim 1, comprising moving said cap feeder (24) in a horizontal
plane.
4. A method as claimed in claim 1 or claim 2, wherein positioning in said third position
(C) said cap (12) vertically straight over said neck (14) of container (16).
5. A method as claimed in claim 1 or claim 2, comprising moving said cap feeder (24)
away from the position over conveyor (26) in a direction perpendicular to said travel
direction (T) and further on back to said position (A) in a direction in parallel
with travel direction (T).
6. A cap feeding device (10) for applying a cap (12) to a neck (14) of a container (16),
comprising
a chute (18) supporting a plurality of caps (12), said chute (18) being arranged to
hold an extending cap (12) in an inclined position in relation to a horizontal plane
with at least a portion of said cap (12) extending outside the chute (18),
a cap feeder (24) comprising at least one carrier (22) extending from an upper surface
(28) of said cap feeder (24),
a drive mechanism (30) supporting cap feeder (24) and arranged to move cap feeder
(24) between a first position (A) and a second position (B) catching said extending
cap (12) on one carrier (22), to move cap feeder (24) further to a third position
(C) above a conveyor (26) arranged to move in a horizontal plane in a travel direction
(T) while supporting containers (16), and back to said first position (A),
at least one gripper or cap holder (32) arranged to lift said at least one cap (12)
from said cap feeder (24) in position (C) and to attach said at least one cap (12)
on a container (16).
7. A cap feeding device (10) as claimed in claim 6, wherein said chute (18) extends in
an inclined position in relation to a horizontal plane.
8. A cap feeding device (10) as claimed in claim 6, wherein said chute (18) is provided
with a cap dispenser (20) at a bottom most section.
9. A cap feeding device (10) as claimed in claim 6, wherein cap feeder (24) is provided
with an inclined section (25) at one end, wherein said inclined section (25) is in
front when cap feeder (24) moves in directions parallel to transport direction (T).
10. A cap feeding device (10) as claimed in claim 6, comprising
a first linear motor (34) operating on a fixed first bar (36) along a line in parallel
with transport direction (T),
a second linear motor (38) fixedly connected to said first linear motor (34) and driving
a second bar (40) in a direction perpendicular to transport direction (T), wherein
cap feeder (24) is connected to second bar (40) to be moved together with second bar
(40).
11. A cap feeding device (10) as claimed in claim 10, wherein first linear motor (34)
supports at least one bushing block (48) slidably supporting a support rod (46) for
movement in parallel with second bar (40), and wherein support rod (46) is connected
to cap feeder (24).