CA1164395A - Spacing mechanism for conveyor lines - Google Patents

Abstract

ABSTRACT

A continuously operable conveyor of the belt type, or the like, for transporting articles such as jars, bottles, or the like, having curvilinear surfaces is provided with stop levers pivotally mounted on the conveyor side guides for engagement with or by said containers to maintain them in proper spaced relationship one from the next both while being transported and when while being held at the terminal station of the mechanism thus preventing compacting forces from being cumulatively transmitted to the leading containers by the trailing containers when the leading containers are restrained from further transport while the conveyor continues to operate.

Description

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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---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 .. . .

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 . .

-5a-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 ~!..~'' r~
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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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-6a-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 ~4 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 9s 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 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 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.

Claims (4)

1. In a conveyor mechanism adapted for the transporting seriatim of articles having curvilinear surfaces from an infeed station to a terminal station:
a) 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 there-between a spacing adapted to allow only a single file, of the respective articles to be passed by the belt conveyor there-between;
b) a stop member disposed between the side guides at a forward portion thereof and adapted to engage a leading article the respective single file to hold same generally stationary even if the belt of the conveyor continues to advance;
c) spacing means for spacing said articles one from the other during their 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;
d) each said lever including an arm engageable by a respective article and rockable thereby about a generally vertical axis thereby to move another arm into position to restrain the forward transport of the next succeeding article being transported by the conveyor mechanism by engaging the next succeeding article;
e) 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.

2. The invention according to claim 1, wherein the side guides are generally vertically placed board-shaped horizontally elongate members disposed one on each side of the conveyor belt.

3. The invention according to claim 2, wherein the levers are pivotally secured to lower edge portions of the board-shaped members.

4. The invention according to claim 1, 2 or 3, including limit means associated with each of said levers for restricting the rotatable movement of each said lever in both directions of rotation.