This disclosure relates generally to the conveying arts and, more particularly, to a conveyor disabler and related methods.
Modular link conveyors have typically been driven by a plurality of laterally spaced, gang driven sprocket, typically located at the transition of the conveyor from the forward to the return run. Recently, another manner of driving such a conveyor has been introduced, namely driving via one or more sprockets positioned alongside a lateral side of the conveyor, as described in PCT Patent Application Serial No. PCT/US2011/036397, the disclosure of which is incorporated herein by reference. Such a side-driven conveyor offers many advantages, including the potential elimination of discontinuous conveyors wherein objects must be transferred from the trailing end of one conveyor to the leading end of another, the elimination of catenaries adjacent a sprocket, and improving the transfer of items along a curved, spiral, or helical path.
While these drive arrangements offer many advantages, they are not without limits. In any of the above drive arrangements, a break in the conveying chain or an irregularity such as a foreign object can cause the drive to improperly interact with the chain. This can result in the drive damaging significant portions of the chain itself, or damage to the drive sprocket.
Accordingly, there is a need for an improvement to the drive arrangement which accounts for the above potential results of an irregularity between the drive and the conveying chain.
An apparatus for use with a driven conveyor comprising a modular link belt including a plurality of outer links along a lateral side of the conveyor comprises a disabler for disabling the driving of the conveyor upon detecting an irregularity in connection with the outer side links.
In one embodiment, the disabler may comprise a follower adapted for engaging the outer side links of the conveyor belt. The follower includes a first position and a second position. The follower is arranged for disabling the drive in the second position.
In some embodiments, the follower comprises a sprocket having a lateral face oriented generally parallel to a plane of a conveying surface of the conveyor belt. The follower may be pivotally mounted for movement between the first and second positions. For example, the follower may be pivotally mounted to a shaft. The follower may also be arranged for contacting an interior surface of the outer side links.
In some embodiments, a switch is provided for disabling the driving of the conveyor in response to the second position of the follower. A guard may also be provided for guarding the follower. The guard may substantially surround the follower.
The apparatus may further include a drive for driving the conveyor. The drive may support the follower, and may include a first sprocket and the follower includes a second sprocket. The first and second sprockets may rotate about generally parallel axes of rotation (e.g., vertical axes).
An apparatus may also comprise a modular link conveyor including a drive for driving the conveyor in a conveying direction, said drive including a drive sprocket for engaging a surface of the links of the conveyor. A follower may be adapted for engaging the surface of the links, said follower capable of moving from a normal position to a disabling position in a direction generally transverse to the conveying direction. A switch may be provided for disabling the driving of the conveyor when the follower moves to the disabling position. In one embodiment, an interior of one of the links includes the surface.
Additionally, an apparatus be provided for use with a modular link conveyor adapted for conveying articles in a conveying direction. The apparatus may comprise a drive contacting at least one link of the conveyor, and a follower contacting the at least one link immediately before the link engaging the driver. The follower is adapted for moving from a normal position to a disabling position. A switch may be provided for disabling the drive when the follower is in the disabling position.
In one embodiment, the follower may be positioned from the drive a distance less than or equal to a length of two links of the conveyor in the conveying direction. In another embodiment, the follower is positioned from the drive a distance less than or equal to a length of five links of the conveyor in the conveying direction.
The follower may be supported by the drive. The drive may include a drive sprocket and an idler sprocket. The follower may engage an interior surface of the link.
An apparatus may also be provided for use with a conveyor adapted for conveying articles in a conveying direction, and including a drive for driving the conveyor in an endless loop including a forward run and a return run. The apparatus includes a first follower for engaging the conveyor along the forward run, the first follower having a normal position to a disabling position, and a second follower for engaging the conveyor along the return run, the second follower having a normal position to a disabling position. The drive may be disabled in the disabling position of the first or second follower.
In some embodiments, the first follower is positioned for rotation in plane above the first follower. The first follower may be rotatable about a first axis and the second follower rotatable about a second axis, wherein the first axis and second axis are spaced apart in the conveying direction. A switch may also be provided for disabling the drive when the first or second follower is in the disabling position.
A spiral conveyor may include any apparatus described above. For example, a further apparatus for conveying objects may include a conveyor adapted for moving along a spiral path, a drive for driving the conveyor along the spiral path, and a follower for engaging an outer surface of the conveyor along the spiral path. The follower may be adapted for moving from a normal position to a disabling position, and further including a switch for disabling the drive when the first or second follower moves to the disabling position.
A further apparatus may be provided for use with a modular link conveyor including a plurality of outer side links and driven by a drive. The apparatus comprises drive sprocket for rotating about a first, generally vertical axis of rotation, and a follower sprocket for rotating about a second axis generally parallel to the first axis of rotation.
In some embodiments, the drive sprocket is arranged for engaging the outer side links. In some embodiments, the follower sprocket is arranged for engaging the outer side links. The follower sprocket may be positioned downstream of the drive sprocket in the conveying direction.
The apparatus may include a plurality of drive sprockets for rotating about a first, generally vertical axis of rotation and a plurality of follower sprockets for rotating about a second axis generally parallel to the first axis of rotation. The follower sprocket may include a normal position and a disabling position, and further a switch may be provided for disabling the drive in the disabling position of the follower. The switch may comprise a proximity switch.
A method for conveying objects using a conveyor belt comprising outer side links and driven by a drive. The method comprises engaging a follower with the outer side links of the conveyor belt, said follower including a normal position and a disabling position. The method further comprises disabling the drive in the disabling position.
The engaging step may comprise engaging an interior surface of the outer side links. The disabling step may comprise actuating a switch controlling the driving of the drive. The method may further include the step of driving the conveyor belt along a linear path, or along a spiral path, or both simultaneously at different locations. The engaging step may comprise engaging the outer side links along a forward run of the conveyor belt, engaging the outer side links along a return run of the conveyor belt, or both. The method may further include a first sprocket for engaging the forward run and a second sprocket for engaging the return run.
A method of operating a driven conveyor including a drive surface, comprising adjusting the driving of the conveyor upon detecting an abnormal condition in a drive surface of the conveyor. The method may further include the step of engaging a drive surface of the conveyor with a follower capable of assuming a disabling condition corresponding to the abnormal condition, and then adjusting the driving of the conveyor in the disabling condition. The adjusting step may comprise halting the driving of the conveyor. The method may further include the step of engaging the drive surface with a drive sprocket.
An apparatus, comprises a conveyor including a drive surface and means for adjusting the driving of the conveyor upon detecting an abnormal condition in a drive surface of the conveyor. The means for adjusting comprises a follower for engaging the drive surface positioned upstream of a driver for engaging the drive surface, and a switch for halting the driving of the conveyor by the driver based on the position of the follower.
With reference to
In such case, the follower 14 may be adapted to provide for the disabling of the conveyor 12 in the disabling condition. For example, the follower 14 may actuate a switch 16, which in turn associates with a drive 18, as illustrated in the schematic diagram of
An optional biasing means (not pictured) may be present to urge the follower 14 into contact with the conveyor under normal operating conditions, while allowing movement to the disabling condition in the event of a conveyor irregularity. The biasing means may be in the form of a spring, hydraulic cylinder, resilient flexible material, or any other structure for urging contact between the follower and the conveyor.
Reference is now made to
A drive 18 is also provided for driving the conveyor 12. In this embodiment, the drive 18 includes a drive sprocket 18a for driving the conveyor 12 along a forward run U. The drive sprocket 18a as shown is mounted with its major plane generally parallel to the conveying surface. In other words, the drive sprocket 18a rotates about a generally vertical axis A when the direction of travel and thus the conveying surface are aligned with a horizontal or otherwise non-vertical plane.
In this arrangement, a follower 14 is also arranged to contact the conveyor 12 as it is driven by the drive 18. This contact may also be with the outer side links 12a of the conveyor 12. The follower 14 may comprise a sprocket 14a mounted for rotation about a vertical axis B generally parallel to the axis A of the drive sprocket 16a. In any case, the follower 14 may be mounted for moving from a first position close to the conveyor 12 to a second position farther away from the conveyor. In the embodiment using the sprocket 14a, this may be achieved by pivotally mounting a support, such as a vertically extending idler shaft, to a stationary support structure (such as the drive 16). A biasing means, such as a spring, may urge the follower 14 to the first position (see
A switch 16 may be associated with the follower 14 and, as noted above, also the drive 18. The switch 16 may be arranged for responding to movement of the follower 14 from the first position to the second position, and disabling the drive 16 as a consequence. This detection may be achieved by detecting the position of the follower 14 relative to a fixed location, such as by using a proximity switch (magnetic, optical, etc.) or the like. A limit as to the relative movement may be provided to determine whether the second position has been reached, and may be pre-determined as desired based on the particular arrangement (including to take into account any chatter or vibrations that may result during the normal course of the follower 14 engaging the chain of the conveyor 12).
As can be appreciated, if the conveyor 12 thus has a significant defect (such as, for example, a broken side link 12a) that would cause the follower 14 to move to the second position, such would trigger the disabling of the drive 18. This would advantageously prevent the defect from harming the drive 18 or otherwise allowing the operation of the conveyor 12 to continue in a compromised condition. Consequently, a potentially catastrophic failure may be avoided.
Movement of the follower 14 to the second, disabling condition thus has the potential to disable the conveyor operation. For this reason, it is preferable to protect against any undesired external influence that would cause accidental triggering. In one embodiment, as shown in
In an alternative embodiment, a trigger 34 may be used to activate the switch 16 for disabling the drive, as perhaps best illustrated in
As noted above, these arrangements can be used on linear conveyors, but may also be used on other arrangements. Thus, for example,
A particular embodiment is shown in
While it may be possible to form the follower 14 (or 20) and drive 18 as a unit, it is possible to form the follower as a separate device that simply communicates with the switch 16 in an indirect fashion. This would advantageously allow for easy and inexpensive retrofitting onto existing drive arrangements. The communication may be direct, as by way of mechanical or electrical link, but could also be through indirect means, such as a wireless radiofrequency signal generated when the movement of the follower 14 is such that an undesired condition is detected.
The conveyor 12 may be side-flexing, and arranged such that the links of adjacent rows may move toward or away from each other as the result of longitudinal compression. In this case, the use of a sprocket 14a as the follower 14 in advance of the drive sprocket 18a has the advantage of regulating the spacing of the links to a generally uniform condition. This helps to ensure that the engagement faces of the links of the conveyor are presented in a generally uniform manner to the drive sprocket 18a, and thus helps to enhance the efficiency and reduce stress and wear on the links as the result of continuous engagement in a sub-optimal manner. However, it is also possible for the follower to take the form of a wheel having a smooth outer surface for engaging the conveyor 12, or even for the follower to take the form of a non-rotating body, such as a pivoting arm, for contacting the conveyor. The disabling position may be closer to or father away from the conveying path relative to the home position.
As noted previously, the follower 14 should be mounted upstream of the drive 18. In the case of a modular link conveyor 12, the follower 14 may be positioned an upstream distance less than a length of five links of the conveyor, as measured in the conveying direction (that is, in the direction of arrow U). However, the follower 14 could be positioned as close as two links away, especially if the links are particularly large or the rate of travel is relatively slow. Likewise, the spacing could be greater or different if dictated by the particular circumstances of the conveying operation.
The foregoing descriptions of various embodiments provide illustration of the inventive concepts. The descriptions are not intended to be exhaustive or to limit the disclosed invention to the precise form disclosed. Modifications or variations are also possible in light of the above teachings. As should be appreciated, any effort to halt the driving of the conveyor may result, at least initially, in a reduction in the driving speed, since the conveyor may continue to travel in the conveying direction even with the drive disabled. The embodiments described above were chosen to provide the best application to thereby enable one of ordinary skill in the art to utilize the inventions in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention.
The disclosures of U.S. Provisional Patent App. Ser. Nos. 61/569,414 and 61/559,814 are incorporated herein by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US12/65234 | 11/15/2012 | WO | 00 | 5/15/2014 |
Number | Date | Country | |
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61559814 | Nov 2011 | US | |
61569414 | Dec 2011 | US |