Note: Descriptions are shown in the official language in which they were submitted.
11338~6
CONVEYORS AND CTechnical Field and Back round of the Invention
g
Conveyors in a wide range of types have
been used heretofore for handling materials of a
wide range of types. Certain conveyors, and more
5 particularly conveyors used with packages such as
bottles, cans, and other similar generally cylindri-
cal, somewhat fragile containers normally conveyed
in an upright position, have employed chain in various
forms.
- Particularly in thé field of conveyors
employed with packages such as containers of the
type described, difficulties have been encountered
as the industry handling such materials has gone
toward one or both of more fragile packages and higher
operating speeds. By way of example only, the bottling
industry has had occasion to adopt non-returnable
bottles which, in order to reduce costs, are more
readil~ breakable than more traditional returnable
bottles. Additionally, development of packaging
machinery used in bottling and canning plants and
-the like has achieved higher production rates, neces-
sitating handling of packages in greater volumes
per unit of time. Efficient handling of increasing ~ - .
~lumes of packages per unit of time has begun to
a5 reguire more positive control over the flow and
11338~6
-2-
movement of such packages or objects.
Persons working in the field of conveyors
using chains thus are presented with a range of pro~lems.
These problems include a need for handling packages
at higher speed, a need for avoiding excessive contact
pressure between relatively fragile packages, and
a need for expanding the usefulness of conveyor chains
while maintaining strength needed for accomplishing
the operating functions required.
i~338~6
Brief Summary of the Invention
With the above discussion in mind, it is an object of
the present invention to provide a conveyor chain of broadened
usefulness and which is readily adaptable to a wide range of
applications. In realizing this object of the present invention,
a conveyor chain having tensile strength characteristics at least
comparable to those of previously used roller chain is constructed
and used in such a way as to permit accomplishing a range of
desired functions. Strength is obtained by the cooperation of
a plurality of elongate links and a plurality of pins, with the
links and pins being chained together in such a way as to bear and
transmit all tensile stress imposed on the chain.
More particularly, the invention provides a conveyor
chain comprising
a plurality of elongate, stamped metallic plate links,
a plurality of metallic pins each penetrating terminal
end portions of two pairs of said links for chaining said links
into first and second spaced apart side length portions,
said links and said pins cooperating for transmitting
tensile stress imposed on said chain, and
a plurality of carrier means, each penetrated by no
more than two of said pins, each having a portion for enclosing
a pin and cooperating with said pin and links penetrated thereby,
and each having a carrier portion projecting laterally from said
chain intermediate said side length portions for engaging an
object to be moved with said chain.
It is desirable to move fragile packages such as glass
containers by means of a chain conveyor while avoiding high
--3--
11338 ~
pressure contact between such packages. In realizing this, a
conveyor chain as herein described cooperates with a plurality
of rollers to define a horizontal supporting surface for packages
which moves in such a manner as to normally convey packages resting
upon the surface while accommodating movement of the conveying
surface beneath and relative to obstructed packages. By means
of relatively free movement of the conveying surface beneath
obstructed packages, the levels of pressure imposed between
engaging obstructed packages is relatively low so as to avoid
package damage.
It is also desirable to accomplish positive positioning
and movement of packages being conveyed. In realizing this,
as herein described, a chain cooperates with associated guides in
such a manner as to positively grip packages being conveyed
between adjacent pairs of grippers or carriers, thereby permitting
the package to be moved at a relatively high rate of speed with
the conveyor chain.
1133846
--s--
Brief Description of Drawings
Some of the objects of the invention having
been stated, other objects will appear as the descrip-
tion proceeds, when taken in connection with the
accompanying drawings, in which--
Figure 1 is an elevation view of a lowpressure conveyor embodying the conveyor chain of
the present invention as used in a first application;
. Figure 2 is a plan view of the conveyor
of Figure l;
Figure 3 is an elevation view, in section,
of a portion of the conveyor of Figures 1 and 2;
Figure 4 is a side elevation view, partially
broken away and partially in section, of a conveyor
1~ chain of the present invention as incorporated into
the conveyor of Figures 1 through 3;
Figure 5 is an exploded perspective view
of certain components of the chain of Figure 4;
Figure 6 is an elevation view, in section,
of portions of the chain of Figure 4, taken generally
along the line 6-6 in Figure 4;
Figure 7 is a partially schematic, partially
broken away view similar to Figure 2;
Figure 8 is an elevation view, partially
in section, of a poxtion of the arrangement of Figure
7, taken generally along the line 8-8 in that Figure;
Figure 9 is a view similar to Figure 7,
showing an alternative arrangement for certain structure
of a low pressure conveyor in accordance with the
present invention;
Figure 10 is a view similar to Figures
9 and 7, showing a further alternative arrangement
for a low pressure conveyor in accordance with the
present invention;
.
11338~6 .
Figures 11, 12, 13 and 14 are a series
of views similar to Figures 4 through 6 and showing
an alternative form of conveyor chain of the present
invention;
Figures 15, 16 and 17 are a series of views
similar to Figures 12, 13 and 14 and showing a modified
form of the conveyor chain of those views;
Figure 18 is a plan view, partially broken
away, of a positive control conveyor incorporating
the conveyor chain of the present invention; and
Figure 19 is a perspective view of a component
of the conveyor chain used in the conveyor of Figure
18.
~338~6
--7--
Detailed Description of the Invention
While the present invention will be described
hereinafter with more particular reference to the
accompanying drawings, it is to be understood at
S the outset of the ollowing description that the
present invention may be modified by persons skilled
in the applicable arts while still achieving operating
characteristics consistent with those to be described.
Accordingly, the following description is to be read
broadly as enabling persons skilled in the applicable
arts to fully utilize the present invention, and
is not to be read as restricting the scope of the
present invention.
Referring now more particularly to Figures
1 through 10, a conveyor chain in accordance with
the present invention is there shown as incorporated
in a low pressure conveyor for packages such as bottles
and t~e like. In the low pressure conveyor of Figures
1 through 10, which is generally indicated at 15,
packages normally move from one apparatus to another
in a bottling or canning plant along a main conveyor
line 16, in a direction indicated by arrows. Normally,
movement of packages along the main conveyor line
16 is unimpeded, in order to move packages from one
apparatus to another along the line. However, in
the event that it is necessary to accumulate any
number of packages at an intermediate location at
which the low pressure conveyor 15 is positioned,
a pair of diversion gates 18A and 18E may be pivoted
into position across the main conveyor 16. An upstream
diversion gate 18A then causes packages moving along
the main conveyor 16 to be diverted onto a horizontal
~onveying surface provided by the low pressure conveyor
15.
~1338~6
-8-
ln accordance with the present invention,
the conveying surface provided by the low pressure
conveyor 1~ is provided, at least in part, by the
particular cooperation of a conveyor chain of a type
5 contemplated by the present invention and sho~n parti-
cularly in Figures 4 through 6. As there shown,
the conveyor chain comprises a plurality of elongate
links 19 and a plurality of pins 20. Preferably,
the links 19 are stamped from metallic plate or sheet
10 material, such as stainless steel. Similarly, the
pins 20 are formed of a suitable metallic material,
~uch as stainless steel. The pins 20 each penetrate
terminal end portions of two pairs of links (Figures-
4 and 6) for chaining the links into first and second
spaced apart side length portions 21A, 21B (Figure
6). The links 19 and pins 20 cooperate or transmitting
tensile stress imposed on the chain. That is, the
strength of the chain in bearing, taking up or transmitting
tension or pulling force is derived from the links
anA pins and the chaining together of those elements.
As will be noted, when such a chain is tensioned
or pulled taut, a straight line through the centers
~ the pins 20 defines a pitch line. The distance
between the centers of adjacent pins 20 is the chain
pitch. The distance between the links, in the direction
of a pin 20, is the chain width and is a measure
of the distance between the first and second spaced
apart side length portions.
In accordance with the present invention,
3~ the chain of Figures 4 through 6 incorporates a plurality
of spacer means generally indicated at 21 and, in
the ~orm now referred to, most clearly shown in Figure
~. Preferably the spacer means 21 is an injection
lded plastic, but it may be made of sintered or
compressed metal or the like. Each spacer means 21
3846
_g
is penetrated by no more than two of the pins 20.
Each of the spacer means 21 has a sleeve portion
for enclosing a pin and for cooperating with the
pin and links which are penetrated by that pin for
spacing the side portions. Each of the spacer means
21 has a carrier portion which projects laterally,
with respect to the pitch length, from the chain
for engaging an object to be moved with the chain.
In the form particularly shown in Figures 1 through
10 and now being described, the carrier portion defines
clip means having a spaced pair o clip slots 24
for receiving rod-like axles 25. Preferably, each
spacer means 21 has a pair of sleeve portions 22
each penetrated by corresponding pin 20. The sleeve
portions 22 have sprocket engaging surfaces for transfer
of driving force to the chain and functioning in
a manner generally similar to the rollers of a conventional
roller chain.
It is noted that a conventional roller
chain (Figure 11) is made up of two kinds of links,
namely roller links and pin links, which are alternately
spaced throughout the length of the chain. In a
conventional chain, a roller link consist~ of two
sets of rollers and bushings, with the bushings being
press fitted into a pair of link plates. A pin link
has two link plates into which are press fitted two
pins. When assembled, the two pins fit in the bushings
of the two adjacent roller links. In the chain of
~igures 4 through 6, alternate links 19 span the
two sleeve portions 22 of a single spacer means 21,
and thus would seemingl~ at least approach the structure
~f a xoller link. Adjacent alternate links 19 span
sleeve portions 22 of adjacent pairs of spacer means
21, chaining together the links and spacer means
.
11338~6
--10--
and ~unctioning somewhat similarly to the pin links
o~ a conventional roller chain.
The conveyor 15 to which the present descrip-
tion is directed comprises sprocket means for mounting
pairs of chains as described hereinabove. More particu-
larly, and as made more clear in Figures 3 through
10, two pairs of chains constructed as described
to this point are mounted on respective sets of sprockets
for movement about corresponding endless paths of
travel, each including a generally horizontal upper
run in which a package supporting horizontal surface
is defined. Two such surfaces are provided, one
in which package movement is away from the main conveyor
16 and another in which package movement is toward
the main conveyor 16, as indicated by arrows in Figure
2. Referring now more particularly to the package
supporting surface mo~ing away from the main conveyor
line 16, a cross shaft 30 extending parallel to the
main conveyor 16 mounts a spaced pair of inlet end
sprockets 31A, 31B about which respective chains
pass. The shaft 30 additionally mounts a control
mechanism roller 32, for purposes to be described
more fully hereinafter. A second cross shaft 34,
spaced some distance from the main conveyor 16, mounts
a cooperating set of sprockets (not visible in the
accompanying drawings) and is driven in rotation
by an appropriate motive power means 35 such as an
electrical motor. The electrical motor 35, driving
the shaft 34, drives the chains entrained about the
entry end sprockets 31A, 31B in movement away from
the main conveyor 16.
The rod-like axles 25 held within the clip
means o~ the spacer means 21 span the distance between
the spaced apart pair of chains which move along
,
~338~6
the closed path of travel defined by the sprockets
mounted on the shafts 30, 34. Due to coordinated
drive of the.two chains from the shaft 34, the axles
25 are maintained in a paxallel array as they move
with the chains. Each axle 25 mounts a plurality
of rollers 28 which are freely rotatable on the axles
25.
Due to the freely rotatable characteristic
. of the roller means 28 mounted on the axles 25, the
1~ conveyor of Figures 1 through 10 accomplishes low
pressure engagement of any obstructed packages moving
therewith. More particularly, the weight of a package
resting upon the roller means 28 and the axles 25
normally is sufficient to prevent rotation of the
roller means 28 relative to the axles.25. In the
absence of such rotation, ana with the axles 25 moving
with the chains in which they are clipped, packaqes
resting upon the horizontal conveying sur~ace are
moved with movement of the chains, as briefly described
20 above. However, in the event that movement of the
packages is obstructed in any manner, such as by
a backing up of packages on the horizontal conveying
~urfaces of the conveyor 15, relatively little force
of engagement against the package is re~uired to
overcome the restraint against rotation existing
between the roller means 28 and the axle 25. With
ro~ation of roller means 28 relative to the axles
25, the conveyor structure moves easily under any
--obstructed package, without imposing drag force on
that package which would give rise to pressure between
the obstructed package and any obstruction such as
a~other package.
1~338~6
The free rotatability of the roller means
28 about the axles 25 opens still other possibilities
for controlling rates of packages movement while
accommodating low obstruction pressures. In forms
S ~f the conveyor here illustrated, advantage is taken
of these characteristics to define an acceleration
zone generally indicated at AZ in Figure ~ in which
packages coming onto the conveyor 15 are accelerated
in movement away from the main conveyor line 16.
More particularly, an auxiliary belt 36 is mounted
within the closed path of travel of the chains described
hereinabove and spans substantially the distance
spanned by the axles 25. The auxiliary belt encircles
the roll 32 and a spaced secondary roll 38 mounted
on a cross shaft 39. As more particularly illustrated
in F~.gures 7 and 8, roller means 28 passing about
the sprockets mounted on the shaft 30 most closely
adjacent the main conveyor line 16 and then moving
away from the main conveyor line 16 are brought into
engagement with the belt 36, and may be rotated relative
to the shafts 25 by any difference in speed between
the speed of the chains by which the axles 25 are
carried and the belt 36. As indicated by arrows
in Figure 8, where the belt 36 remains stationary,
movement of the chains away from the main conveyor
line 16 causes the roller means 28 to be driven in
xotation in such a direction as to accelerate package
m~vement. Alternatives to this arrangement will
be pointed out more fully hereinafter.
Packages moving away from the main conveyor
line 16 onto the low pressure conveyor 15 are guided
between outside guide rails 40 and inside guide rails
41. Near an exit end of the conveyor moving away
1133846
~rom the main conveyor line 16, the outer guide rails
40 are turned to divert packages onto a conveying
~urface moving back toward the main conveyor line
16 (Figure 2). The conveying surface moving back
toward the main conveying line 16 is formed in a
~anner similar to the conveying surface moving away
from the main conveyor line 16, namely by the use
o~ a pair of chains as described hereinabove mounting
a series of axles in parallel array and with roller
means provided on the axles. Sprockets for mounting
the second set of chains and associated components
are mounted on the shafts 30, 34 as described herein-
above and motive power is provided by suitable means
such as an electrical motor 42.
In order to provide a range of possibilities
~or controlling package movement in a zone such as
the accelera~ion zone AZ described hereinabove, it
is contemplated that various provisions may be made
for fixing or driving a surface such as the belt
36 which engages the roller means 28 of a conveyor
section in accordance with the present invention.
Two such variations are illustrated in Figures 9
and 10, and the possibilities for selecting drive
arrangements will become more clear from the following
2~ discussion of Figures 7, 9 and 10.
More particularly, in Figure 7, an auxiliary
drive chain 44 i5 provided for selectively connecting
a shaft 39 by which the belt 36 may be driven with
the shaft 30 which is driven in rotation by the second
~rive motor 42. An electromagnetically operated
clutch 4~ is provided which may selectively connect
the drive chain 44 and shaft 39 with the shaft 30
driven by the second motor 42. Should the electromagnetic
1133846
clutch 45 be energized to couple together those compo-
nents, then the belt 36 would be driven in a direction
opposite to the direction of movement of the chains
passing thereabout, providing an increased speed
of rotation for the roller means 28 as they move
through the acceleration zone AZ. Such an increased
speed of rotation for the roller means 28 would thus
further accelerate movement of packages away from
the main conveyor line 16. Alternatively, and as
illustrated in Figure 9 where comparable reference
characters of a 100 order series have been used,
the clutch 145 may be effective to couple the drive
chain 144 to the sprocket 131A, causing the belt
136 to move in the same direction and at the same
speed as the chains carrying the axles 125 and the
rollers 128 mounted thereon. In such event, a greater
resistance wauld be imposed to relative rotation
of the roller means 128 about their corresponding
axles 125, opening the possibility of exerting a
greater pressure of engagement between an obstructed
package and any obstruction. Further, and as illustrated
in ~igure 10 where reference characters of a 200
order series have been applied, an independent motor
246 operating if desired through an appropriate variable
speed transmission or other speed control unit 248
may drive the shaft 239 in whatever rotational direction
and at whatever rotational speed is desired, in order
to provide either a retardation zone or an acceleration
~one by controlling rotation o~ the rollers 228.
The present invention contemplates that
the carrier means, such as are shown in Figures 4
through 6 and are described above as spacer means,
may take other forms. In particular, two such forms
1133846
are illustrated in Figures 11 through 17, in which ~-
reference characters consistent with those applied
in Figures 4 through 6 are used with the addition
of a postscript B for one form in Figures ll through
14 and a postscript C for the form of Figures 15
through 17. The distinction between the forms of
Figures 11 through 17 and those of Figures 4 through
6 resides in the pin enclosing portions of the carrier
means of Figures 11 through 17 being formed as parallel,
spaced apart leg portions 27B, 27C for receiving
and for gripping therebetween the side ~ength portions
of a substantially conventionally roller chain. That
is, the depending leg portions 27B, 27C (Figures
12 and 15) straddle or extend downwardly beside the
lengths of the chain. Holes (Figure 14) or recesses
(Figure 17) are provided or a snap lock engagement
with the ends of the link penetrating pins. The
distinction between the form of Figures 11 through
14 and that of Figures 15 through 17 is that the
outer surface of the second form (Figures 15 through
17) is smooth and unbroken by any opening aligned
with the pins. Stated differently, the recesses
which receive the pins are "blind" or closed at the
outer surfaces thereof. This may be deemed desirable
for some circumstances where cleanliness or protection
of pins in a roller chain is deemed to be of significance.
The conveyor chain of the present invention,
as described he~einabove, is contemplated as having
utility beyond the low pressure conveyor 15 of Figures
1 through 10. One such further use of the~onveyor
c~ain described is illustrated in Figures ~ and
, where comparable reference characters of a 300
~rder series have been applied. As there shown,
the carrier portion of the spacer means 321 defines
11338~6
-16-
gripper means having gripping surfaces. Packages,
~uch as bottles B are guided by appropriate guide
means such as guide rods 340 to be inserted between
the carrier portions of adjacent spacer means in
a conveyor chain, as the conveyor chain is passed
about a sprocket. At such position, the carrier
portions of adjacent spacer means are separated,
so that objects to be carried with the conveyor may
be inserted there into. As the conveyor chain completes
its turn about the sprocket and goes forward into
a straight line run, the carrier portions of adjacent
spacer means are moved closer together, gripping
a package such as the bottle B firmly between a pair
of carrier portions. Such positive engagement with
a package permits handling of the package at elevated
speeds, by providing more accurate positioning and
contîol over the package. In the particular form
B illustrated, the conveyor of Figures ~ and ~ has
8procket means arranged so that the chain moves in
a horizontal plane and bottles moving to the conveyor
chain and transported thereby may be supported by
underlying conveying surfaces where appropriate.
In the drawings and specification, there
has been set forth a preferred embodiment of the
invention, and although specific terms are employed,
they are used in a generic and descriptive sense
only and not for purposes of limitation.
~, . . .
