Abstract:
An adjustable guide rail system for guiding containers transported on a conveyor in a container processing production line that allows adjustment of the distance between the opposing guide rails to accommodate containers of different dimensions and configurations. The adjustable guide rail system comprises sections of guide rail, a reversible motorized actuator and a motion converter driven by said reversible motorized actuator which is coupled to the sections of guide rail to automatically adjust the width of the path of the containers being transported on the conveyor.

Description:
FILED OF THE INVENTION 
     The invention relates to guide rail systems for guiding containers transported on a conveyor in a packaging line or container processing production line and more particularly to guide rail systems that allow adjustment of the distance between the opposing guide rails to accommodate containers of different dimensions and configurations. 
     BACKGROUND OF THE INVENTION 
     In the container industry, conveyor systems are used to transport containers between various processing stations. Guide rails are typically provided on the sides of the conveyor to ensure that containers will remain in line along the path of travel established by the conveyor belt. The guide rails that are commonly used in the industry can be adjusted to accommodate different container sizes by using simple manual knobs. To perform the adjustment procedure, the operator releases the knobs, positions the guide rail manually at the desired position and then tightens the knobs to lock the guide rails in place. Conventional guide rail systems, however, fail to provide a quick means of adjusting the distance between opposing guide rails. An operator must physically go to each guide rail sections and manually adjust the distance between the guide rail and the center of the conveyor belt or between opposing guide rails. An operator must repeat this procedure for each section of guide rails and on both sides of the conveyor belt. Considering that production lines may have numerous sections to adjust, it may represent an enormous amount of set up time during which the production line is inactive. If a production line is subject to multiple changes of container sizes due to the nature of the industry, the loss of production time is compounded making the production line less efficient. 
     Thus there is a need in the industry to provide a guide rail adjustment system for conveyor belt that can rapidly be adjusted to accommodate containers of various sizes. 
     OBJECTS AND STATEMENT OF THE INVENTION 
     It is an object of the invention to provide an adjustable guide rail system for conveyor belt that can rapidly be adjusted to accommodate containers of various sizes. 
     As embodied and broadly described herein, the invention provides a selfpowered adjustable guide rail system for guiding containers transported on a conveyor in a container processing production line. The adjustable guide rail system usually comprises at least two sections of guide rail, one on each side of the conveyor for guiding containers, the sections of guide rail are mounted to the conveyor in a generally parallel, facing and coextensive relationship, and are adjustably movable toward the longitudinal centerline of the conveyor or away therefrom. It also comprises a reversible motorized actuator; a motion converter driven by the reversible motorized actuator and coupled to the sections of guide rail for moving same toward the centerline when the actuator operates in a first direction, and for moving the sections of guide rail away from the centerline when the actuator operates in a second direction, thereby adjusting the width of the path of the containers being transported on the conveyor. 
     Advantageously, the self-powered adjustable guide rail system further comprises control means generating an output signal representative of the required motion of the sections of guide rail, the output signal being applied to the motorized actuator and causing same to move to a predetermined setting relative to the centerline. 
     Preferably, the motion converter comprises a cam member movable longitudinally and having a pair of diverging grooves having the same angular deviation relative to the longitudinal centerline. The cam member is connected to the sections of guide rail through inwardly directed sliding members supporting at one end the sections of guide rail and at the other end having cam followers slidably engaging the diverging grooves, thereby transmitting motion of the cam member to each section of guide rail. 
     As embodied and broadly described herein, the invention also provides a self-powered adjustable double guide rails system for guiding containers transported on a conveyor in a container processing production line, the adjustable guide rails system comprising at least two sections of guide rails, one on each side of said conveyor for guiding containers. The sections of guide rails are mounted to the conveyor in a generally parallel, facing and coextensive relationship, and are adjustably movable toward the longitudinal centerline of the conveyor or away therefrom. Each sections of guide rails further comprises at least two generally parallel, side by side rails. The sections of guide rails define two paths for containers being transported; one section of guide rails define a right side of each path, the other section of guide rails define a left side of each path; It also comprises a reversible motorized actuator; a motion converter driven by the reversible motorized actuator and coupled to the sections of guide rails for moving same toward each other when the actuator operates in a first direction, and for moving the sections of guide rails away from each other when the actuator operates in a second direction, thereby adjusting the width of the path of the containers being transported on the conveyor. 
     As embodied and broadly described herein, the invention also provides a conveyor system for a container processing production line, having a supporting structure, a conveyor belt mounted to, and supported by the structure and movable along the longitudinal axis of the structure and at least two sections of guide rail disposed above the conveyor belt for guiding containers thereon. The sections of guide rail are supported by the structure in a generally parallel, facing and coextensive relationship, and are adjustably movable toward a longitudinal centerline of the conveyor or away therefrom. The conveyor also comprises a reversible motorized actuator, a motion converter driven by the reversible motorized actuator and coupled to the sections of guide rail for moving the sections of guide rail toward the centerline when the actuator operates in a first direction, and for moving the sections of guide rail away from the centerline when said actuator operates in a second direction, thereby adjusting the width of the path of the containers being transported on the conveyor. 
     As embodied and broadly described herein, the invention also provides a self-powered adjustable guide rail system for guiding containers transported on a conveyor in a container processing production line comprising at least one movable guide rail disposed above the conveyor for guiding containers thereon. The guide rail is adjustably movable transversely of the conveyor to accommodate containers of different configurations or sizes. It also comprises a reversible motorized actuator and a motion converter driven by the reversible motorized actuator and coupled to the guide rail for moving same in one direction when the actuator operates in a first direction, and for moving the guide rail in the opposite direction when the actuator operates in a second direction, thereby adjusting the path of the containers being transported on the conveyor. 
    
    
     Other objects and features of the invention will become apparent by reference to the following description and the drawings. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A detailed description of preferred embodiments of the present invention is provided herein below, by way of example only, with reference to the accompanying drawings, in which: 
     FIG. 1 is a perspective view of a single lane conveyor with a guide rail system according to the invention; 
     FIG. 2 is a top plan view of the conveyor system of FIG. 1 with containers on the conveyor; 
     FIG. 3 is a side elevational view of the conveyor system of FIG. 2; 
     FIG. 4 is a sectional view taken along line  4 — 4  of the conveyor system of FIG. 2; 
     FIG. 5 is a bottom view of a cam member as used in a guide rail system according to the invention; 
     FIG. 6 is a bottom view of a portion of the guide rail system of FIG. 1; 
     FIG. 7 is a bottom view of another portion of the guide rail system of FIG. 1; 
     FIG. 8 is a perspective view of a dual lane conveyor with a guide rail system according to the invention; 
     FIG. 9 is a top plan view of the guide rail system of FIG. 8 with containers on the conveyor; 
     FIG. 10 is a side elevational view of the guide rail system of FIG. 8; 
     FIG. 11 is a sectional view taken along line  11 — 11  of the guide rail system of FIG.  9 ; 
    
    
     In the drawings, preferred embodiments of the invention are illustrated by way of examples. It is to be expressly understood that the description and drawings are only for the purpose of illustration and are an aid for understanding. They are not intended to be a definition of the limits of the invention. 
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIGS. 1,  2  and  3  show a section of a single lane conveyor  220  adapted to transport containers  30  to and from a processing station(not shown) in a packaging line such as used in the pharmaceutical or cosmetic industry. Conveyor  220  has a conveyor belt  22  of any suitable design mounted to a supporting structure  26  and movable along the longitudinal axis of supporting structure  26 . The supporting structure  26  also features legs (not shown) resting on the floor and stabilizing the structure. Guide rail sections  20  are located one on each side of conveyor belt  22  and each guide rail  20  has a pair of parallel rails  21   a  and  21   b  each having a contacting surface  23  facing inwardly toward longitudinal centerline  28 . Rails  21   a  and  21   b  guide and prevent containers  30  from falling off conveyor  22 . Only two guide rail sections  20  are shown in FIG. 1 to simplify the illustration. However, in a normal packaging line, a succession of guide rail sections will be used almost the entire length of conveyor  220  to insure proper guiding of containers  30  between processing stations. 
     Guide rail sections  20  are secured to uprights  24  by holders  25  which maintain the guide rail sections  20  at a predetermined height above conveyor  220 . 
     Uprights  24  are retained to supporting structure  26  by sliding arms  34 . Guide rail sections  20  are movable toward or away from longitudinal centerline  28  and provide adjustment for the various sizes and configurations of containers  30 . Arrows  32  indicate the general direction of motion of each guide rail section  20 . 
     An actuating mechanism which will be described in detail further down, is located underneath an inverted U-shaped shroud  46  which is part of supporting structure  26  and protects the mechanism from any spillage that may occur on conveyor  220 . Sliding arms  34  extend through shroud  46  and are linked to the actuating mechanism and to uprights  24 . Sliding arms  34  transfer the necessary motion to guide rail sections  20  in order to adjust the distance therebetween. 
     Referring now to FIG. 4 which is a cross-sectional view of the self-powered adjustable guide rail of FIG. 1, rails  21   a  and  21   b  each have rigid frame  81  wedged in a receptacle  82  by an angular peg  83  which is maintained in place by a screw  84  which extends through spacer  25  into a threaded hole in upright  24 . Uprights  24  are rigidly connected to a pair of sliding arms  34 . As shown in FIG. 4, sliding arms  34  have threaded ends  222  which extend into threaded bores in uprights  24  which have closely conforming sunk sockets  224  for the outer end portions  226  of the sliding arms  34 . Sliding arms  34  are slidably supported and guided by bushings  36 . This paired arrangement of bushings  36  and sliding arms  34  provides a stable supporting structure for uprights  24  and guide rail sections  20 . A cam follower  38  interconnects sliding arms  34  at their inner ends so that both sliding arms  34  move together. Cam follower  38  engages a cam plate  40 . FIG. 5 illustrates a cam plate  40  in isolation viewed from above. Cam plate  40  comprises a pair of diverging grooves  60 , one for each uprights  24  and a pair of longitudinal grooves  62 . It should be noted that diverging grooves  60  have the same angular deviation relative to the longitudinal axis defined by longitudinal grooves  62 , although in opposite directions. This arrangement ensures equal lateral displacement of both cam followers  38  and of the guide rail sections  20  that they control. 
     As shown in FIG. 4, cam follower  38  engages cam plate  40  through one of the two diverging grooves  60 . Cam plate  40  is maintained in a substantially parallel orientation relative to conveyor  220  by a passageway  42  cut out in bushings supporting members  44 . Cam plate  40  is supported by the lower portion of passageway  42  to maintain cam plate  40  aligned with the central portion of cam follower  38 . The assembly of cam follower  38  and cam plate  40  is positioned under conveyor belt  22  and is protected from possible spillage of containers  30  by shroud  46  surrounding the assembly yet providing access to it from opening  48 . Shroud  46  can be made of any suitable material including, in particular, stainless steel metal. 
     Referring now to FIG. 6 which illustrate the self-powered adjustable guide rail system viewed through opening  48  of FIG. 4, an actuator  49 , in the form of an stepping motor  50  having a threaded shaft  52 , is rigidly mounted to supporting structure  26  and is connected to two cam plates  40  located at spaced apart location at opposite sides of actuator  49  via connecting bars  54 . It can be seen that each cam followers  38  is confined to the adjacent one of the two diverging grooves  60  of cam plate  40 . Longitudinal grooves  62  receive guide posts  56  which cause cam plates  40  to move in a straight line. Posts  56  can also serve to stop cam plates  40  when they reach the end of grooves  62 . 
     When stepping motor  50  is activated, its rotational motion is transmitted to threaded shaft  52  which advances longitudinally thereby transforming the rotational motion of stepping motor  50  into a translatory motion along the longitudinal axis of conveyor  22 . Threaded shaft  52 , linked to cam plates  40  by connecting bars  54 , imparts a linear translatory movement in the longitudinal direction, to cam plates  40 . As cam plates  40  move longitudinally, diverging grooves  60  impart a lateral motion to cam followers  38 . Cam plates  40  thereby act as motion converters transforming a movement in the longitudinal direction into a lateral movement. Cam followers  38  are pushed or pulled transversely by the motion of diverging grooves  60 , sliding arms  34  transfer that transverse displacement to uprights  24  and to guide rail section  20  to adjust the position of each guide rail section relative to longitudinal centerline  28 . 
     FIG. 6 illustrates the self-powered adjustable guide rail system in the position where each cam plate  40  reaches the end of its path in the direction of arrow  90 . Each cam follower  38  is at, or near the end of a diverging groove  60  and the uprights  24  has been moved to the outermost position in the direction of arrows  100 . From this position, the actuator system may be moved in the direction of arrow  91  to adjust guide rail sections  20  inwardly in the direction of arrows  101 . 
     FIG. 7 illustrates another portion of the self-powered adjustable guide rail system which is normally linked to either end of the portion shown in FIG.  6 . It should be noted that actuator  49  is absent and is replaced by a single connecting bar  54  linking each cam plate  40 . It must be understood that a motorized actuator  49  is not required between each pair of cam plates  40 . Connecting bars  54  link cam plates  40  together to form chains of cam plates  40  which are connected to both sides of an actuator  49 . The number of cam plates  40  connected to a single actuator  49  is a function of the power of actuator  49  and of other design consideration. Hence, actuator  49  provides (((motivity))) to a chain of cam plates  40 . Preferably, a chain of cam plates  40  operated by a single actuator  49  will be adapted to move independently of another chain of cam plates  40  operated by second actuator  49 . 
     In FIG. 7, each cam plate  40  is at the end of its path in the direction of arrow  93 , each cam follower  38  has been moved to the other extremity of a diverging grooves  60  and each upright  24  has been moved in the direction of arrows  105  to its innermost position. The self-powered adjustable guide rail system is in the position wherein each section of guide rail is at the closest distance from longitudinal centerline  28 . From this position, the system may be moved in the direction of arrow  92  to adjust guide rail sections  20  outwardly in the direction of arrows  106 . 
     In operation, actuator  49  receives an electrical signal and moves accordingly. The longitudinal motion of actuator  49  is transferred to connecting bars  54  which move each cam plate  40  of a chain of cam plates in one direction. The longitudinal displacement of cam plates  40  imparts a lateral motion to each cam follower  38  engaged in a diverging groove  60 . Cam followers  38  push or pull sliding arms  34  which in turn move uprights  24  thereby moving guide rail sections  20  toward or away from longitudinal centerline  28 . 
     A control system generates an electrical signal applied to actuator  49  in order to move guide rail sections  20  to the desired position relative to longitudinal centerline  28 . The control system may be a simple manually operated push button or switch which sends an electrical signal to actuator  49  to move it in either direction or it may be a computer which has in memory data pertaining to various container sizes so that simply entering the code of the container will send an appropriate signal to the actuator  49  to move guide rail sections  20  to a pre-determined position relative to longitudinal centerline  28 . The control system may be anything in between these two systems; the degree of sophistication of the control system being a matter of preference and necessity. 
     Stepping motor  50  is activated in one direction or in the other direction by pulse signals. Each pulse corresponds to a set incremental displacement of threaded shaft  52 . For example: 1 pulse=1 mm. A preset number of pulses will provide the required movement of guide rail section  20 . With a manually operated switch or a push button, the duration of the signal will determine the number of pulse whereas a more sophisticated control system will generate the exact number of pulses required to reach the desired position of guide rail sections  20 . 
     In a more sophisticated control system, two types of encoders are available. An incremental encoder requires guide rail sections  20  to return to a Home or Zero position, normally the outermost position from longitudinal centerline  28  shown in FIG. 6, before sending a pre-determined number of pulses to actuator  40 . An absolute encoder uses a feedback signal which determines the position of guide rail sections  20  so that pulses are sent to actuator  49  according to the difference between the initial position and the target position. Both types of encoder work well however, the absolute encoder is preferred as it moves guide rail section  20  directly to the target position and is therefore faster. 
     A variety of actuators  49  available on the market can readily achieve what stepping motor  50  in combination with threaded shaft  52  accomplishes. For example, a motorized linear actuator known as a motorized ball screw with feedback potentiometer provides a reliable actuator allowing the position of its internal threaded shaft to be determined remotely. The signal of the potentiometer can be used to position guide rail sections  20  so that a signal corresponding to the difference between the initial position and the target position is sent to actuator  49 . A servo motor may also be used which provides its own feedback signal and allows quick positioning of guide rail sections  20 . The cost of servo motor however can be prohibitive in this application. An ordinary DC motor may also be used for this application although not with as much precision. The duration of the electrical signal sent to the ordinary DC motor determines the distance of travel in a given direction. The motor however will tend to coast slightly beyond the electrical signal cut off and this coasting has to be accounted for in the duration of the signal sent so that the target position of guide rail sections  20  will not be overshot. 
     As a variant of the self-powered adjustable guide rail system, it is possible to maintain one guide rail section  20  fixed relative to longitudinal centerline  28  and provide adjustment of the distance with the opposing guide rail section  20  by moving only one guide rail section. This may be particularly useful when a specific processing station has one side of the conveyor as a reference point and requires that containers enter the processing station with one of its sides always in the same position as opposed to a processing station that requires containers to enter with the center of the containers in the same position. To achieve this side alignment of containers, only one of the two guide rail section  20  has movable uprights, sliding arms and a cam follower in a groove  60  of a cam plate  40 . The fixed guide rail section  20  may be mounted rigidly to the supporting structure  26  by any conventional means. 
     FIGS. 8,  9 ,  10  and  11  illustrate a second embodiment of a self-powered adjustable guide rail system. In this embodiment, the conveyor  230  has two lanes on each sides of centerline  28 . The actuating mechanism located underneath the inverted U-shaped shroud  46  is identical to the previously described embodiment of the invention. Each guide rail section comprises a first and second guide rail. The right hand guide rail section comprises a first guide rail  251  located near the right outer edge of conveyor belt  225  and a second guide rail  253  located on the left hand side of centerline  28 . Guide rails  251  and  253  are connected together and to uprights  261  and  262  by bridges  257  and  258 . The left hand guide rail section comprises a first guide rail  254  located near the left outer edge of conveyor belt  225  and a second guide rail  252  located on the right hand side of centerline  28 . Guide rails  254  and  252  are connected together and to uprights  261  and  262  by bridges  259  and  260 . Bridges  257 ,  258  and  259 ,  260  extends upwardly from uprights  261 ,  262 ,  263 ,  264  to a point over and above conveyor belt  225 , then laterally across conveyor belt  225  to a point beyond longitudinal centerline  28  of conveyor  230 , and downwardly to a point near the surface of conveyor belt  225  where second guide rails  252  and  253  are attached. Second guide rail  253  is oriented in the same general direction as first guide rail  251  and second guide rail  252  is oriented in the same general direction as first guide rail  254 . Each second guide rail  252  and  253  are retained and secured to the extremities of bridges  257 ,  258  and  259 ,  260  by a screw  280  located between the pair of rails defining second guide rails  252  and  253 . 
     This dual lane arrangement defines two paths  241  and  242  for containers  30  being transported by conveyor belt  225 . The right hand side of each path  241  and  242  is defined by guide rails  251  and  253  while the left hand side of each path  241  and  242  is defined by guide rails  252  and  254 . Path  241  is thereby defined by guide rails  251  and  252  and path  242  is defined by guide rails  253  and  254 . Guide rails  251  and  253  move in the opposite direction of guide rails  252  and  254 . When the system is actuated, both guide rails  251  and  253  move in the same direction while both guide rails  252  and  254  move in the opposite direction thereby adjusting the width of both path  241  and  242  simultaneously. 
     FIG. 11 show a cross-sectional view of the dual lane system. It can be seen that cam follower  38  engages cam plate  40  in the same manner as previously described and sliding arms  34  are connected to both ends of cam follower  38  on one side and to uprights  262  and  264  on the other side. The same assembly as previously described imparts motion to each uprights. Arrows  77  illustrate that first guide rail  251  and second guide rail  253  move in the one direction and arrows  78  illustrate that the opposing first guide rail  254  and second guide rail  252  move in the opposite direction. 
     All figures represent guide rail sections mounted on two uprights as a way of illustrating the invention. It is understood that each sections of guide rail may be longer and have more than two uprights without departing from the spirit of the invention. 
     The above description of preferred embodiments should not be interpreted in a limiting manner since other variations, modifications and refinements are possible within the spirit and scope of the present invention. The scope of the invention is defined in the appended claims and their equivalents.