Note: Descriptions are shown in the official language in which they were submitted.
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SPACING MECHANISM FO~ CONVEYOR LINES
DESC~IPT-tON
TECHNICAL FIEL~
This invention relates generally to a conveying
means useable or effective for transporting articles
of like shape and dimensions from an in-feed or
receiving station to an out-feed or discharge
station. More particularly, this invention relates
to conveyors of the type aforesaid wherein the
articles being fed are required to be in predeter-
mined, spaced relationship to one another at the
discharge s-tation, in order to permit further handl-
ing -thereof automatically without the necessity of
human control or intervention.
This invention has particular utility with
conveyors employed in high-speed automated packaging
lines wherein containers, such as a bottle or a jar,
are carried from one processing station, such as, --
for example, a high-speed filler and capper to a
case packing station wherein the containers are
automatically removed from the conveyor and inserted
into packing cases for shipment. Conveyors utilized
for this purpose may comprise an endless belt or
flat top chain continuously driven and suitably
supported for horizontal travel from the in-feed to
the discharge station of the system. The containers
may be maintained in substantial longitudinal reg-
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istration with the belt by opposed side guides
extending in the direction of belt travel. In
co~ventional eq-uipment of this type, the conveyor
belt or chain is ordinarily driven at a velocity
slightly greater than that of the mechanism, such as
a case packer, operating at the discharge end of the
conveyor in order to assure the availability of
containers at the precise time required for proper
operation of the case packer. The slightly greater
velocity of the conveyor be~t necessarily results in
a longitudinal bunching or compacting of containers,
one against the other, starting at the discharge end
of the conveyor belt. The containers are in
frictional engagement with the belt so that when
compacted at the discharge end of the belt they slip
relative thereto, with the same frictional force of
the belt on each container being transferred from
one container to the next in a cumulative manner so
as to impart to the lead container of the compacted
group the total force frictionally applied by the
belt to the trailing containers of the group. -Thus,
the amount of force applied to any one container in
the compacted group is directly proportional to the
number of containers trailing within the group.
In conventional equipment, when containers having
a generally oval configuration in horizontal cross
section are being processed in equipment of this
type, assuming that said containers are oriented
with their major a~es substantially parallel to
the direction of belt travel, the forces transmitted
to the ends of the containers by the compacting
action as aforesaid tend to skew each container s~
that its major axiS deviates substantiall~ from
parallel relation to the direction of belt travel.
This causes a given container to either skew the
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preceding container i.n the opposite direction or to
partially overtake the immediately preceding con-
tainer and become wedged between said preceding
container and an associated guide rai.L. When thus
wedged, the force applied to such container is
-transmitted to the preceding container in a
magnified manner due to the camming effect caused ~y
its wedged orientation resulting in an overstrain
not tolerable by the system or the containers and
manifested by either a feed jam or dis-figurement of
one or more of the containers. Under such circum- ::.
stances the containers, if made of a brittle
ma-terial such as glass, would likely shatter and if
made of a flexible material, such as lightweight or
thin plas-tic, would become deformed or possibly
burst under the forces applied thereto under such
circumstances.
BA~KGROUN~ ART
The above-mentioned problems arising on con-
veyor lines from -the use of containers which are
generally oval in horizontal cross sectlon are also
pointed out in prior U.S. Patent No. 3,321,096
issued May 23, 1967 to Carl G. Hebel, and is the
subject matter to which said prior patent is
: 25 addressed. Said prior patent was concerned with
oval containers made of glass or other bri-ttle
ma-terial, and in accordance with the disclosure of
said prior patent the problem was met by slightly
- modifying the oval contour of ~he containers them-
selves so as to provide small flat surfaces on the
container at locations where they can abut one
another or contact the guide rails for the conveyor,
so as to transmit compacting forces from one con-
tainer to the next longitudinally rather than
rotatably or -torque-wise which flat surfaces were
not of a size which could be readi.ly discernible or
substantially affect -the generally oval appearance
and overall con:Eiguration of the container.
Another factor which contributes to the problem
of iarnming on the conveyor line by oval co-n-tainers
made of plastic material, especially a thermoplastic
material, is the temperature to which said containers
are sub~jected. In instances where the conveyor is
utilized to convey containers from the Eiller sta-
tion of the production line to the case packer, such
as in the example herein disclosed, the temperature "~
of the product affects the handling characteristics
of the container. In many instances the product
must be in a heated condition for filling purposes,
and in such circumstances the container, if made ofthermoplastic material, especially lightweight or
-thin-walled construction, becomes much more yielding
and readily deformable when subjected to compacting
forces on a conveyor line. Thus, the same forces
which could cause breakage in the case of glass or
other brittle materials can3 in the case of con-
-tainers made of lightweight or thermoplastic
material, result in substantial deformation or even
rupture of the container structures.
Another prior art disclosure which relates
generally to mechanisms for spacing successive
articles being fed in line on continuously operable
conveyor is ~.S. Patent to Darrus O. Riggs et al.
No. 4,096,939 and issued June 27, 197~. This prior
discl.osure relates to means for spacing successively
conveyed bottles for introduction to a tes-~ing device
wherein the leading container or bottle is always in
motion and the stop member consists of a single
lever pivotally mounted and operating under the
influence of a bias spring to return the lever to
unblocking or unrestraining position. The present
apparatus is distinguished therefrom in that the spacing
means comprising a pair of pivotal levers operating as a
pair, neither of which is under spring bias and both of
which are rocked from and to restraining position with
respect to a trailing container by the camming action of
containers passing therebetween.
Another prior art reference of interest is U.S.
Patent 3,263,794, issued August 2, 1966, (R.H. Burton et al).
In this reference, there is a series of article spacing
elements each pivoted about a horizontal axis transverse
to a longitudinal endless conveyor. As an article loaded
on the conveyor engages the leading end of a lever pivoted
about the transverse axis, the rear end protrudes upwardly
to form an engagement part of a subse~uent article. The
drawback of this arrangement is seen particularly in that
it requires su~ficient space to be left in the conveyor
surface for the lifting of the spacing elements. Thus,
the arrangement, while probably suitable for specially
designed conveyors, is totally unsuitable in the art of
conveyor belts utilizing an ordinary rubber belt or the
like which, of course, is preferred in many applications
due to its simplicity in maintenance, use and a relatively
low cost.
The art of spacing elements has been considerably
advanced by the provision proposed in British Patent
1,090,070 published November 8, 1967 ~Jagenberg-Werke A.G.)
wherein *wo armed detent levers are pivo~ed around a
stationary pivot project and the free ends thereof project
alternately into the part of movement of the articles. The
pivot axis of detents are generally vertical and are disposed
to both sides of a conveyor path. Accordingly, the use of
rubber or the like conveyor belt is possible as there is
no need for any operative elements to protrude through the
plane of movement of the conveyor belt. When a production
line is to be changed from one container to another, it is
necessary to replace the two armed detent levers such as
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to correspond to the desired spacing of the containers
depending on the shape and overall configuration oE the
container. In the quoted British Patent Specification,
such exchange is a relatively lengthy and expensive matter
due to the fact that in all embodiments, the sole means for
providing the spacing between the containers are the two
armed detent levers. Accordingly, if a container is conical,
two different sets of detent levers have to be provided
in the first place. If the production program is switched
to another shape, both rows of the detent levers have to
be replaced and substituted by another set of two sets of
levers, one for the upper row of detents, unless the
containers are purely cylindric in which case the shape
and size of the levers would be the same both for the
upper and the lower row of detents on each side of the conveyor.
DISCL~SU~E OF 7$1~ IN~NTI~N
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It is, therefore, an object of this invention to
improve the operation of conveyors of the type herein
disclosed by maintaining a succession of containers in
properly spaced relationship one to the other.
It is a further object of this invention to
enable the use on high-speed conveyor lines of containers
having an oval or other curvilinear configuration in
horizontal cross section without the risk of conveyor
jamming when the container travel is halted by means
other than stoppage of the conveyor itself~
It is a still further object oE the invention
to enable the use of containers having an oval or other
curvilinear configuration in cross section on high-speed
conveyor lines even when filled with a liquid product in
a hea~ed condition.
A still another object of the present invention
is in simplifying the arrangement of the mechanism to be
used in conveyor lines such as to reduce the cost of
maintenance, the initial cost of the overall device and
also to simplify and reduce the time required for a
changeover of a conveyor line from one type of a product
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or container to ano-ther, which would present a substantial
improvement and savings over the arrangement as described
in British Patent 1,090,070 referred to above.
Further objects of the invention together with
the features contributing thereto and advantages accruing
therefrom will be apparent from the following description
when read in conjunction with the drawings wherein:
In general terms, the present invention provides,
in a conveyor mechanism adapted for the transporting
seriatim of articles having curvilinear sur~aces rom an
infeed station to a terminal s1:ation: a pair of opposed
side guides extending along a conveyor belt path with one
of said guides being disposed at each side of a belt
conveyor path, the side guides being stationary and being
spaced apart such as to provide therebetween a spacing
adapted to allow only a single file of the respective
articles to be passed by the conveyor therebetween; stop
member disposed between the side guides and a ~orward
portion thereof and adapted to engage a leading article
of the respective single file`to hold same generally
stationary even if the belt of the conveyor continues to
advance; spacing means for spacing said articles one from
the other during said transport by said mechanism, said
spacing means being formed by levers pivotally mounted on
the respective guides for engagement with each said article
in pairs; each said lever including an arm en~ageable by
a respective article a~d rockable thereby about a
generally vertical axis thereby to move another arm into
position to rsstrain the forward transport of the next
succeeding article being transported by the conveyor
mechanism by engaging the next succeediny article; said
levers being aLl located within a single plane generally
parallel with the plane of movement of the conveyor belt
and spaced from said plane a distance less than that of
the spacing of a top portion of each of the side guides
from the said plane.
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BRIEF DESCRIPTION OF DRAWINGS
Fig. 1 i5 a view in side elevation of the
discharge end of a horizontal conveyor adapted by means
of the wlthin invention to handle containers having an
oval configuration in horizontal cross section.
Fig. 2 is a plan view, partly in section, of
the structure shown in Fig. 1~
Fig. 3 is a sectional view of said structure
taken along the line 3-3 of Fig. 1.
Fig. 4 is a view similar to Fig. 2 but
illustrating the inventive features hereof for use
with containers having a round configuration in
horizontal cross section.
Referring now to Figs. l, 2 and 3, there are
shown three oval containers 10 a-c at the discharge
end or terminal station of a horizontal conveyor
which operates to transport the bottles from right
to left as shown by the directional arrow of Fig. 2.
The conveyor, which may be of any well-known type,
is herein shown as comprising an endless b~lt 12
drawn about a drive pulley 13 by which it is normally
continuously driven. The upper horizontal reach of
the belt supports the containers and may in turn be
supported in horizontal alignment by one or more
support rails 14. Side guides 15a, b in the form of
bars or the like, extending along and above the
horizontal reach of belt 12, prevent lateral dis-
placement of the containers from the belt and act to
maintain the feeding containers generally in longi-
tudinal registration. It of course will be appreci-
ated that the spacing of ~he guide rails 15a, b must
allow for a limited amount of clearance in order to
prevent binding and to allow for free uninterrupted
or unimpeded travel of each container to its intended
destination.
As shown, the leading container lOa has been
carried up to a stop bar 16 disposed across the path
of the containers and holding the leading container
lOa in a predetermined limit position which is
required for the proper operation of associated
handling mechanism, which in this case could be a
case packer or the like disposed alongside the
terminal end of the conveyor and effective for
transferring a plurality of conveyors when in proper
alignment and registration at the discharge end of
the conveyor into a shipping carton or case, also
not shown. Proper operation of the associated case
packi~g mechanism requires that a plurality of
containers be precisely registered or indexed at the
terminal end of thè conveyor so that for each cyclic
operation of the case packer said plurality, for
example four containers, may be removed from the
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conveyor simultaneously. This in turn means that
the leading container lOa must await the arrival of
the next three following containers in preparation
for each said cyclic operation. During ~his time it
will be understood that unless other ~eans are
o-therwise provided, the successive containers will
exert compressive or compacting forces on each con-
tainer before it until they are removed by a cyclic
operation of the case packer. Thus, it will be seen
that in the normal operati~n of all components of
the packaging line, there is always a period during
which -the bottles tend -to become compacted at the
end of the line while awaiting the next cyclic
operatîon of the case packer, and the number of
bottles involved in each cyclic operation of the
case packer determines the amount of compressive
force applied to the leading bottles on the con-
veyor. However, in cases where for one reason or
another the case packer malfunctions or fails to
opera-te while the conveyor is nevertheless still
operating, the pile-up or compacting will progress
at a rapid rate to accumulatively apply increasing
compressive force on the leading containers. Under
such circumstances, unless means were provided for
avoiding the problem, the containers at -the head of
the line would be unable to wi-thstand the continually -
increasing compacting forces and would become wedged
between an abutting container and the side rail
guides and eventually either break, in the case of
glass containers or burst in a case of thermo-
plastic containers, or somehow create a jam and
misoperation requiring shutdown of the entire line
until the condition can be corrected.
In accordance wi-th the present invention the
means for preventing the cumulative application of
compacting forces on the leading containers include
container stops 20a, b in the form of levers arranged
in pairs and p:ivotally secured or attached to the
bottom of the side rail guides 15a J 15b by any
suitable means such as shouldered pivot bolts 21.
Each stop 20a, 20b of a pair have a configwration
which is a mirror image of the other one of the pair
and comprises essentially, with respect to its
pivotal axis 3 a forwardly extending arm and a rearward-
ly extend:ing arm, the ends of which are disposed forcontact with successive containers 10 supported by
the belt 12 of the conveyor. The successive pairs
of stops 20a, b, are spaced along the respective
guide rail at a pitch distallce which is at least
equal to the length of the greatest longitudinal
dimension of the associated containers. The precise
shape and length of the stops depend in part upon
the particular configuration of the containers and
the desired spacing, if any, between successive
containers when brough-t to a halt at the discharge
end of the conveyor. In the present example the
containers are intended to be maintained in just
barely touching relationship -to one another for
proper registration with the associated case packing
mechanism. The levers are freely rotatable in a
hori~ontal plane under the the influence of the ;:-
containers 10, when able to move relative thereto,
between limit positions determined by a limit pin 22
projecting from the bottom of each side guide rail
for engagement by the forwardly extending arm of
each of the stops, and also by a limit pin 23
similarly located with respect -to the rearwardly
extending arm of each s-top member 20.
In operation, with particular reference to Fig.
2, it will be seen that the leading bottle lOa when
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limited by the conveyor stop 16 has its greatest
width dimension at the point of contact with the
.Eorwardly extenting arms of stops 20a, 20b so as to
in affect maintain said arms spread apart in which
position the rearwardly extending arms of said stops
project into the line of or path of travel of the
next container 10b so as to restrain its travel at
a position in which it is just barely touching the
leading container 10a. Likewise container 10b
assumes the same relative positioning wi-th respect
to the next pair of stops 20a, 20b the rearwardly .~.
extending arms of which are rocked into position
to limit the forward travel of the next container
10c when it reaches said stops so positioned under
the influence of container 10b. Thus, the forces
which otherwise would prevail in the absence of
such stops are removed from the leading container
10a and are resisted by the stops as is clearly
evident. As container 10c continues to -travel
forwardly it first engages the forwardly extending
arms of the adjacent stops 20a, 20b so as to rock
the rearwardly extending arms thereof in-to position
for stopping the next container, not shown, until
container 10c arrives and is stopped in turn by the
stops under the influence of container 10b. Thus,
the entire line may be provided with stops so that i-
no container on the line is able to exert a compact-
ing force on the container preceding it.
When a sufficient number of containers ha~e
arrived at the transfer or terminal end of the
conveyor line to synchronize with the operation of
the associated handling mechanism, i.e., a case
packer or the like, said containers may be removed
vertically from the-conveyor at which time all the
succeeding containers will be allowed to progress
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and in turn engage the stops between which the
removed containers were alined and proceed in a sort
of stepwise fashion continuously in turn camming
apart the next succeeding pair of stops until the
first container of the ne~t group arrives and is
limited by the conveyor stop 16. Thus, all backed-
up containers on the line will proceed in turn
simultaneously engaging the next pair of stops in a
serial type of operation until the nex-t cyclic
operation of the case packer mechanism removes the
leading group of containers, and -the operation
repeats and continues in the same manner.
While the invention as above described and
shown has particular utility in cases where bottles
of oval configuration in cross section are involved,
it also has utility in cases where bottles of round
configuration in cross section are involved and an
illustration of the invention in association with
containers of this type is shown in Fig. 4. In
cases where the containers are round in horizontal
cross section, the problem to be addressed is not so
much a jamming of the conveyors as a result of
skewing action but more of relieving pressure of
compac-ting forces so as to enable the use of thinner
walled containers or lighter weight plastic then
otherwise would be the case, since there are no ~
compacting pressures to contend with. As shown in
Fig. 4 the paired stops 35a, 35b are of slightly
different configuration due to the different con-
figuration of the containers themselves, but they
operate in the same manner as described above in
reference to Figs. 1 and 2. It will be understood
that the containers 30a, 30b shown in Fig. 4 are or
a round configuration in cross section at their
greatest horizontal dimension. If it were desired
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to have some space between successive bottles when
stopped at the terminal end, in preparation for case
packing or even when traveling along the conveyor,
this could readily be accomplished by lengthening
the rearwardly extending arm o~ the stops 35a, 35b in
the case of Fig. 4 or the stops 20a, 20b in the case
of oval containers shown in Figs. 1 and 2, the
operation thereof otherwise being the same except
for the amount of space between successive con-
tainers.
Thus, it will be seen that the invention is -
highly effective in cases of any shape container
wherein the cross sectional dimension of greatest
magnitude is either oval, round or any other form of
curvilinear surface which in all cases leads to
cumulative compacting forces, and in the case of
oval containers to skewing and jamming, in each case
the leading containers being relieved of cumulative
deforming or possibly shattering torces which are
readily by this means easily avoided.
It will be understood that the invention has
been illustrated in connection with a single lane
conveyor mechanism for purposes of simplicity of
disclosure. In practice, the invention could be
applied to conveyors of multiple lanes side-by-side
in which case one row of stops for the adjacent lane '``
could be mounted on the same pivots as for the
alined row of the first lane, and if desired special
brackets could be provided so as to enable both
stops on the same pivot point to have rotatable
limit positions, through appropriate configuration
of the mounting bracket or the like, to permit the
function of the stops to be achieved in the same
manner in all lanes of the apparatus.
While there has been shown and described what
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is considered to be a preferred embodiMent of the
invention, it will of course be understood that
changes in form and detail cowld be readily
accomplished and made without departing from the
spirit of the invention and the general principles
disclosed. It is, therefore, intended that the
invention be not limited to the exact form and
details herein shown, for :illustrative purposes, and
to nothing less than the whole of the invention
hereinabove described as hereinafter claimed.
