Container capping apparatus

A capping machine comprises a rotating carriage positioned above a conveyor delivering open neck containers to a work station position, the carriage including circumferentially positioned sockets that receive snap-lock caps in a fixed orientation from a second conveyor. The carriage rotates about an axis transverse to the direction of conveyance of the first conveyor so that the proximate carriage position closest to the first conveyor has a velocity in the same direction as the direction of conveyance of the container. As the tangential position of the cap on the carriage changes as the cap approaches the proximate carriage position, the cap is progressively engaged against the open neck of the container. At the proximate carriage position, the cap is positioned for sealing engagement with the neck of the container. In the preferred embodiment, the first conveyor is a linear conveyor, and as the leading edge of the cap engages the neck of the container, the velocity component of the cap in the direction of conveyance of the first conveyor exceeds the velocity of the conveyor, whereby the speed of the container through the work station is controlled wholly by the speed of the carriage to assure proper engagement of the cap with the container. The second conveyor means also includes means for feeding the caps to the carriage in a predetermined alignment, and the carriage includes cap receiving heads adapted to maintain the alignment of the caps as they are displaced about the axis of the carriage.

BACKGROUND OF THE INVENTION 
I. Field of the Present Invention 
The present invention relates generally to apparatus for automaticaly 
installing caps on necked containers, and more particularly to apparatus 
for installing particularly configured caps adapted to snap-lock with the 
neck of the container. 
II. Description of the Prior Art 
It has been previously been known to automate the installation of caps on 
necked containers for simple cap structures. For example, an internally 
threaded cap can be applied to an externally threaded neck by holding the 
cap in the chuck or the like and then rotating the chuck as it descends in 
registration with the container neck. Typically, the containers are moved 
along the conveyor line, and the chuck must therefore be linearly 
displaced at the same speed as the container while the cap remains in the 
chuck and in engagement with the container neck. While such devices are 
advantageous for use in packaging containers of the simple cap structure, 
the previously known apparatus are not well adapted for use in installing 
specially configured caps. 
A particularly advantageous form of cap which has become available includes 
a pour spout for controlling the flow of contents from the container as 
the container is tilted. One particular type of pour spout cap includes a 
raised spout extending upwardly beyond a rim and supported by an inclined 
base disposed below the rim. The base has an opening at its lowermost end 
communicating with an elongated slot in the pour spout. The rim includes a 
depending lip having means for engaging a peripheral projection on the 
neck of the container so that the cap can be snap-locked in position on 
the neck. The inner peripheral wall of the rim is threaded to receive a 
closure cap which completely covers the open spout, and thus the open neck 
of the container. When the closure cap is removed, the closure cap is 
designed to measure a predetermined amount of the contents of the 
container being poured into the closure cap through the spout. A 
particular advantage of such packaging enclosures is that any residue 
contained within the closure cap is returned to the container when the 
closure cap is remounted to the rim of the pour cap since the residue 
drains along the inclined base of the pour cap into the container. Since 
the pour cap has a spout extending upwardly above the rim, and a base 
inclined downwardly from the rim, the previously known capping apparatus 
are not well adapted for installing such caps. 
Moreover, when the peripheral projection on the neck of the container is 
continuous around the entire neck, a substantial amount of force would be 
necessary to concentrically depress the cap upon the neck of the 
container. Moreover, displacement of the means for depressing the cap 
along a moving conveyor line must be timed accurately to correspond with 
the movement of the container along the line. The application of a 
depressive force when the cap is misaligned with respect to the neck, or 
application of an excessive force, can cause damage to the cap or the 
container neck and prevent tight sealing engagement between the cap and 
the container. 
SUMMARY OF THE PRESENT INVENTION 
The present invention overcomes the above-mentioned disadvantages by 
providing a capping apparatus in which the caps are circumferentially 
arranged on a carriage rotating above a main conveyor which passes 
containers through a work station position. The carriage rotates about an 
axis perpendicular to the direction of conveyance of the main conveyor and 
perpendicular to the axis of the neck of the container as the container is 
supported by the conveyor at the work station position. As the carriage 
rotates to displace a cap toward the proximate carriage position closest 
to the conveyor at the work station, a container is positioned by the main 
conveyor for receipt of the cap upon the neck of the container. The 
tangential position of the cap on the carriage at a first predetermined 
position along the direction of conveyance causes a leading edge of the 
cap to become engaged with the neck of the container. As the leading edge 
of the cap reaches the proximate carriage position, the leading edge of 
the rim of the cap is seated upon the neck, and further movement of the 
cap through the proximate carriage position progressively engages the cap 
on the neck to its fully seated position. A synchronizing means times the 
arrival of a cap at the work station simultaneously with the arrival of a 
container at the work station. 
In the preferred embodiment, the main conveyor linearly displaces the 
containers through the work station position. Moreover, as the carriage 
rotates, the velocity of the cap in the direction of conveyance of the 
main conveyor progressively increases as the cap approaches the proximate 
carriage position. Thus, the rotational speed of the carriage is selected 
so that the velocity of the cap in the direction of conveyance exceeds the 
speed of the first conveyor, whereby the engagement of the leading edge of 
the cap with the container neck causes displacement of the container along 
the main conveyor. Consequently, the carriage controls the speed of the 
container through the work station to assure proper alignment between the 
cap and the container neck. 
The carriage of the preferred embodiment includes means for receiving the 
cap in the form of at least one head defining a socket adapted to receive 
the pour spout section of a pouring cap. In addition, the head includes 
means for maintaining the alignment of the cap within the socket. Such 
means is in the form of a shoulder adapted to engage the peripheral edges 
of a slotted opening in the pour spout, and includes means for adjusting 
the width of the shoulder. A means for retaining the cap within the socket 
as the carriage rotates about its axis comprises a resiliently biased 
plunger adapted to be received within the open end of the pour spout. The 
head also includes means for deflecting the trailing edge of the container 
neck to ease engagement of the trailing edge of the cap with the neck of 
the container. Preferably, the means for deflecting comprises a 
resiliently biased lever mounted adjacent to trailing edge of the socket. 
In the preferred embodiment, a second conveyor delivers the caps to the 
carriage in a fixed orientation and includes means for individually 
feeding the caps into the sockets in the carriage. The feeding means 
comprises a plunger aligned in registration with a cap retaining station 
adjacent the end of the second conveyor at a distal carriage position 
opposite to the proximate carriage position. As a plunger actuating 
mechanism reciprocates the plunger, a setter retracts the penultimate cap 
away from the endmost cap at the retaining station. In addition the setter 
assures proper orientation of the cap before it reaches the receiving 
station for insertion into the socket. The actuating mechanism for the 
plunger is also timed to coincide with the arrival of a cap at the end 
station of the second conveyor and the arrival of a carriage socket at the 
receiving station. Moreover, a timing means in the plunger actuating 
mechanism assures that the setter retracts the penultimate cap prior to 
actuation of the plunger. 
Thus, the present invention provides a novel capping apparatus in which a 
rotating carriage tangentially aligns a cap for progressive engagement 
with the open neck of a container. Moreover, the apparatus is particularly 
well adapted for use in installing particularly configured caps having 
pour spouts extending above a cap rim and an inclined base extending below 
the cap rim, and assures that such caps are in proper alignment engaged 
with the open neck of a container. Furthermore, the capping apparatus 
eliminates the risk of damaging the cap or the container neck during 
installation of a snap lock cap on the container neck. These and other 
advantages will become apparent as the invention is discussed in greater 
detail in the following detailed description.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring first to FIG. 1, a capping apparatus 10 for installing caps 12 on 
an open necked container 14 comprises a rotatable carriage 16 fixedly 
positioned above a first conveyor 18. Each cap 12 has a rim 20 with a 
depending lip having means for lockingly engaging an annular projection on 
the open neck 22 of the container 14. The pour spout extends upwardly 
above the rim 20 from an inclined base extending below the rim 20. The 
inner peripheral wall of the rim surrounding the pour spout is threaded to 
receive a correspondingly threaded closure cap (not shown). Although the 
apparatus is particularly well adapted for installation of the 
particularly configured cap 12 described above, it will be understood that 
the apparatus can also be used to apply other known caps adapted to 
lockingly engage an open neck of a container. 
The containers 14 in the preferred embodiment have flat bottoms 15, and 
circular necks 22, whereby a linear conveyor track 26 of the conveyor 18 
in the preferred embodiment supports the containers 14 in an upright 
position. However, the apparatus of the present invention is not limited 
to such cap and neck configurations, for example, it will be understood 
that correspondingly configured caps and necks of elliptical or 
rectangular shape can be installed, whereby the axis 21 can be defined as 
the central line extending perpendicular to a transverse cross sectional 
plane through the opening in the neck 22. Moreover, the central axis of 
the neck can be angled with respect to the base of the container so long 
as the conveyor 18 or work station frame 25 stably supports the container 
at the work station position 24 as the cap 12 is installed on the neck 22. 
In addition, although the bottoms 15 of the containers 14 are referred to 
as flat 15, it is to be understood that the term refers only to the fact 
the container can be stably supported upon a flat surface, and it is not 
to be understood as a limitation of the type of container for which the 
capping apparatus of the present invention can be used. Moreover, the 
limitation includes containers which have configured bottoms such as the 
concave central portion 17 shown in hidden line in FIG. 1, but which can 
be stably supported on a flat surface. 
The carriage 16 is mounted at a work station position 24 generally defined 
by a frame 25 along the route of the conveyor 18. The track 26 of the 
conveyor 18 includes a plurality of spaced apart projections 28 adapted to 
engage the containers 14 for controlled displacement in the direction of 
conveyance as shown by the arrow 30 in FIG. 1. The carriage 16 is 
rotatably mounted to the frame 25 at the work station position 24. The 
axis of rotation 32 of the carriage 16 is spaced apart from the track 26, 
perpendicular to the direction of the conveyance 30 and perpendicular to 
the central axis 21 of the neck 22 of the container 14. 
As indicated generally at 34 in FIG. 2, means for rotatably driving the 
carriage 16 rotatably drives the carriage in the direction of arrow 36 
shown in FIG. 1. The carriage 16 includes at least one, and preferably a 
plurality of, cap receiving means 38 at circumferential positions of the 
carriage 16, and the axis of rotation of the carriage is positioned so 
that the proximate position of the carriage 16 closest to the track 26 
positions a cap 12 in its locking engagement position with the neck 22 of 
a container 14 supported on the track 26. As shown in FIG. 2, the carriage 
16 is constructed of two side plates 80 adapted to support three cap 
receiving means 38 therebetween and fixed for rotation with a shaft 81 
rotatably mounted to the frame 25 by appropriate bearings. Guide bars 27 
are supported by the frame 25 to align the containers 14 beneath the 
carriage 16. Preferably, the means 34 for rotatably driving the carriage 
synchronizes rotation of the carriage with the speed of the conveyor track 
26 as indicated diagrammatically by the coupling belt 35. 
Still referring to FIGS. 1 and 2, the capping apparatus 10 also includes a 
second conveyor 40 for delivering caps to the carriage 16. In the 
preferred embodiment, the conveyor 40 includes a conveyor track 42 which 
transfers a row of caps 12 from an alignment mechanism indicated 
diagrammatically at 44. The alignment mechanism assures that the caps 12 
are aligned with the pour spout positioned for insertion within a 
receiving means 38 on the carriage 16. The alignment mechanism 44 can also 
include heating means for softening a pliable seal member inserted in the 
rim of the cap for tightly sealing the cap 12 to the container neck 22 
when the cap 12 is installed. The apparatus of the preferred embodiment 
also includes a feeder 46 for individually inserting the aligned caps 12 
in the receiving means 38 of the carriage 16. 
The feeder 46 comprises a plunger 48 disposed above a retaining station 50 
adjacent the end of the conveyor track 42. The plunger 48 is reciprocated 
by an actuating means 52 to displace the endmost cap 12 from the retaining 
station 50 into the receiving means 38 on the carriage 16. The actuating 
means 52 comprises a rotatable cam 54 whose rotation is timed in 
coordination with rotation of the carriage 16, for example, by a chain and 
sprocket connection 56 as shown in FIGS. 1 and 2, so that depression of 
the plunger occurs when a receiving means 38 of the carriage 16 is 
positioned beneath the retaining station 50 for receipt of the cap 12. A 
cam follower 58 on the pivoted lever arm 60 follows the peripheral surface 
of the cam 54 to control the reciprocating action of the plunger 48. 
The feeder 46 also includes a setter 62 positioned upstream of the 
retaining station 50. The setter includes a plunger 64 which is aligned 
for extension into the opening in the bottom of a cap 12 on the conveyor 
track 42 to restrict displacement towards the retaining station 50. A 
setter actuating means 66, preferably in the form of a pneumatic cylinder, 
is synchronized by appropriate means such as the photo-electric cell 
switch 68, which monitors displacement of the detent in the cam 54, and 
causes extension of the plunger 64 a short time before actuation of the 
plunger 48. Thus, the setter prevents displacement of the penultimate cap 
toward the receiving station 50 which would interfere with insertion of 
the end cap 12 in the receiving means 38. Preferably, the plunger 64 
includes a tapered head 70 so that the cap into which it extends actually 
retracts away from the retaining station 50 a small distance to assure 
that interference with insertion of the endmost cap is avoided. In the 
preferred embodiment, the tapered head 70 is conical to conform with a 
concave depression 71 in the cap 12. Engagement of the conical head 70 in 
the concave depression prepositions the cap 12 in proper alignment before 
it enters the retaining station 50 for insertion in the receiving means 
38. 
Referring now to FIGS. 3-5, each receiving means 38 comprises a head 74 
having a base 76 and a socket body 78. The base 78 is rigidly secured 
between the side plates 80 of the carriage 16. The socket body 78 is 
supported in a substantially fixed position with respect to the base 76 by 
pivot pin 82 extending through a bore in the socket body and registering 
apertures in the side plates 80. The side plates 80 include bushings 84 
mounted in the registering apertures so that the socket body 78 can pivot 
about the axis of the mounting pin 82. In addition, as is best shown in 
FIG. 4, a spring 86 resiliently urges the socket body 78 to a fixed 
position with respect to the base 76, and provides a floating support for 
the socket body. As a result, slight deviations in the height of the 
container or the neck size can be accommodated by the head 74 without 
causing distortion or destruction of the cap 12, the neck 22 or the socket 
body 78. 
The socket body 78 defines a socket 88 adapted to receive the pour spout 
portion of the cap 12, and includes a peripheral ledge 90 upon which the 
rim 20 of the cap 12 can be seated. A guide block 92 is mounted within the 
socket by a mounting bolt 94. The guide block 92 includes face surfaces 98 
and a projection extending outwardly from the face having lateral guide 
surfaces 96. The face and lateral guide surfaces abut against the 
peripheral edges of the slotted opening in the pour spout of the cap 12. 
The guide block is split, each half being joined by a threaded adjustment 
screw so that the width between the lateral surface portions is 
adjustable. The guide surfaces on the guide block 92 fixedly retain the 
cap in a fixed orientation within the socket 88. 
In addition, a plunger 102 extending upwardly through an aperture in the 
bottom of the cap socket 88 is resiliently biased upwardly into the socket 
88 by a spring 104 entrained within a spring socket in the base 76. While 
the plunger 102 is easily depressed when the cap 12 is pushed into or 
pulled from the socket 88, the rounded end of the plunger 102 abuts 
against the interior of the spout wall so that the cap cannot 
inadvertantly slip out of the socket during rotation of the carriage 16. 
In particular, the plunger 102 prevents lateral displacement along the 
inclined face surfaces 98. 
Direct outward displacement of the cap 12 from the socket 88 is prevented 
by the lip 106 of a lever 108. The lever 108 is pivotally secured by a 
pivot pin 110 within a slot in the socket body 78. A spring 112 
resiliently urges the lever toward the position shown in solid line in 
FIG. 4 and is retained within a spring socket in the base 76. Thus, the 
lever 108 is normally retained in a position where the rounded lip 106 is 
positioned at the edge of the rim 20 of the cap 12. However, the lip 
includes a cutout 114 which enables a portion of the lip 106 to slide past 
the edge of the rim for a purpose to be described in greater detail 
hereinafter. 
Referring now to FIG. 6, it can be seen that as the head 74 approaches the 
proximate carriage position closest to the conveyor track 26, the cap is 
aligned so that the inclined base of the cap 12 fits within the open neck 
22, and a leading edge of the rim 20 is positioned for engagement with a 
leading portion of the neck 22. As the leading edge of the cap reaches the 
proximate carriage position, the leading edge of the rim 20 becomes fully 
engaged with the neck 22. As the head 74 moves toward the proximate 
carriage position shown in FIG. 7, the cap 12 is progressively forced into 
engagement with the neck 22 of the container 14. At the same time, while 
the curved surface of the lip 106 permits the container neck to slip into 
the trailing portion of the cap 12, the spring tension on the lever 108 
from the spring 112 causes a slight deflection of the neck which minimizes 
the force necessary to fully engage the cap on the neck in its fully 
seated and interlocked position. 
At the first predetermined position at which the leading edge of the cap 12 
engages the neck 22, the velocity component of the cap 12 in the direction 
of conveyance 30 approaches and exceeds the speed at which the projection 
28 moves the container 14 in the direction of conveyance 30. Thus, as 
shown in FIG. 7, the container 70 slides along the track 26 of the first 
conveyor and becomes displaced from the projection 28. As a result, the 
speed of the container 14 is controlled wholly by the carriage 16 at the 
work station position to assure proper alignment between the cap 12 and 
the container neck 22. Thus, it will be understood that the projections 28 
are utilized to synchronize the arrival of the container 14 at the work 
station simultaneously with the arrival of the head 74 at the work 
station, but the speed of the container during engagement of the cap 12 on 
the container 14 is controlled wholly by the velocity of the carriage 16 
at the work station position. 
As shown in FIG. 8, once the cap 12 is tightly engaged on the neck of the 
container 14, displacement of the head 74 upwardly from the cap permits 
the cap to be retracted from the socket 88 as the container continues 
along the conveyor track 26 at the speed of the conveyor track 26. 
Moreover, while the change in tangential position of the cap with respect 
to the neck 22 as the cap approaches the proximate carriage position 
permits progressive engagement of the cap upon the neck from the first 
predetermined position along the direction of conveyance 30, the 
tangential alignment of the head 74 permits release of the cap from the 
head 74 downstream of the proximate carriage position. Moreover, the 
present invention eliminates the risk of damaging the caps or containers 
which can occur when snap-lock caps are not properly aligned with the neck 
when forceably applied to the container neck. 
Thus, it will be understood that the present invention provides a capping 
apparatus which is well adapted for applying particularly configured pour 
caps adapted to lockingly engage a container neck. Moreover, the apparatus 
can install a wide variety of caps in a manner which avoids damage to the 
cap, the neck of the container, and the installing apparatus. 
Nevertheless, the apparatus provides a tight sealing engagement between 
the cap and the container. Moreover, the capping apparatus of the present 
invention prevents misalignment of the cap with respect to the container 
which can occur in other known automated capping apparatus. 
Having thus described the present invention, many modifications thereto 
will become apparent to those skilled in the art to which it pertains 
without departing from the scope and spirit of the present invention as 
defined in the appending claims. For example, the main conveyor need not 
be a linear conveyor but can be a curved conveyor or even a rotating 
carriage similar to the carriage 16 so that the velocity of the container 
carriage in the direction of conveyance 30 matches the velocity of the cap 
carriage in that direction through the work station position.