Freewheel flow track systems

This application is a continuation of co-pending U.S. Nonprovisional application Ser. No. 10/857,184 entitled “Freewheel Flow Track Systems,” filed May 28, 2004, which is a divisional of U.S. Nonprovisional application Ser. No. 09/956,253 entitled “Freewheel Flow Track Systems,” filed Sep. 20, 2001, now abandoned, which claims the benefit of U.S. Provisional Application No. 60/234,568 entitled “Pallet Conveying System,” filed Sep. 22, 2000, each of which is hereby incorporated by reference.

The steel wheel track system, or skate wheel track system, is one of the most commonly used flow track systems in the material handling industry. The steel wheel track system comprises a track assembly including one or more parallel track frames. Each track frame includes a pair of parallel steel frame members, also known as “profiles”, and multiple wheel assemblies mounted between the profiles. Each wheel assembly includes a steel wheel rotatably mounted on an axle that extends between the profiles transverse to the track flow direction. The wheels are typically 1.9 inches in diameter and 0.50 inches to 0.56 inches in width. The wheels comprise steel outer shells having thicknesses between 22 gage and 13 gage, depending upon the particular application in which the wheels are used. Additionally, a number of ball bearings are used in the wheels to increase the load capacity of the wheels and to enable the wheels to roll. Each wheel will typically have between six and twelve ball bearings. The load capacity of a skate wheel can vary between twenty-five pounds to one hundred-fifty pounds, depending on the thickness of the shell and the number of bearings the wheel contains.

Steel wheel track systems are predominantly used in picking applications. Picking applications are applications in which a loaded wooden pallet is placed on the track assembly at an entrance end of the track assembly, rolled forward to an exit end of the track assembly and then presented to a picker that takes cartons off the pallet for order picking and shipping to stores or other locations. Steel wheel track systems are also used in applications in which cartons are placed directly on the track assembly and rolled from an entrance end of the track assembly to an exit end of the track assembly.

There are several problems that occur with existing steel wheel track systems. One problem occurs because the pallets used in picking operations are sometimes low quality pallets that have broken bottom boards and/or soft, damaged wood. Due to the narrowness of the steel wheels presently used (only 0.50 inches to 0.56 inches wide), the wheels tend to get caught by broken boards or embed themselves in soft wood. Likewise, when damaged cartons are transported directly on a track assembly, the wheels tend to embed themselves in damaged sections of the cartons. In such situations, a picking operator must pull the pallet or carton towards the exit end of the track assembly using a tool called a shepherd\'s hook. In doing so, the operator must often exert high forces to keep the pallet moving towards the exit end of the track assembly. As a result, operators have slipped, fallen and sustained injuries while using shepherd\'s tools to move pallets.

Another problem occurs when low quality pallets are used. When a skate wheel track is designed, consideration is given to the loads that the skate wheels must support. The load that each wheel supports is a factor of the load being carried by the pallets, the length of the pallets used and the number of wheels on the track assembly for a given length (thus, the number of wheels supporting the pallet). Based on the load, the length of the pallets and the number of wheels for a given length, the required load capacity for each wheel can be calculated. A particular wheel design (i.e., outer shell thickness and number of bearings) can be selected. However, the wheels are subjected to unusually high loads when a pallet is used that is missing a front or a back board, or that is otherwise shorter than the pallets the tracking system is designed to carry. This is due to the fact that a fewer number of wheels support the shorter pallet. The wheels may not be capable of supporting the elevated loads and may break, requiring the picking operator to use a shepherd\'s tool to move the pallets forward along the track assembly. As stated before, this can result in injury to the picking operator.

Yet another problem exists with present steel wheel track systems. Many flow systems, such as those in environments that are subject to FDA cleanliness requirements, require washdowns. However, the steel wheels used in present flow track systems are susceptible to corrosion. Thus, frequent washdowns can damage steel wheels and cap eventually render them inoperable.

It is an object of the present invention to provide a flow track system that will allow pallets and cartons to flow reliably, efficiently, and in a way that is safe for picking operators. It is a further object of the invention to provide a flow track system that can be used in environments that require washdowns.

The present invention discloses Freewheel Flow Track Systems for transporting pallets and/or cartons in heavy-duty pallet and carton flow applications. According to certain embodiments of the invention, a flow track system comprising multiple, longitudinally extending, parallel track sub-assemblies is disclosed. Each track sub-assembly includes a track frame comprising a pair of parallel profiles, and multiple wheel assemblies connected to the pair of profiles and arranged in a row extending from an entrance end of the track assembly to an exit end of the track assembly. The wheel assemblies each comprise an axle extending between the pair of profiles and a polycarbonate resin wheel rotatably mounted on the axle.

A lubricant coating is fixed to and bonded with the axle. The polycarbonate resin wheels are constructed from a polycarbonate-based resin that is impregnated with a lubricant for providing lifetime lubrication to the wheels. The lubricant in the wheels and the lubricant coating of the axles give the wheel assemblies a low coefficient of friction, high rollability and high durability. The wheels each include a hub, a rim that is concentric with the hub, a web that connects the hub to the rim and ribs that connect the hub to the rim through the web. The wheel assemblies are self-lubricating and are of high strength for transporting heavy pallets and cartons.

According to other embodiments of the invention, a flow track system including a single track assembly suitable for directly supporting cartons is disclosed. The track assembly includes a wide track frame. The track frame includes a pair of parallel profiles and multiple wheel assemblies connected to the profiles and arranged in a row extending from an entrance end of the track assembly to an exit end of the track assembly. In this embodiment, each wheel assembly includes an axle extending between the profiles and a multiple wheels rotatably mounted on the axle in a row extending transverse to the track flow direction.

The freewheel flow track systems disclosed by the invention provide reliable, efficient and safe pallet and carton flow. The flow track assemblies disclosed by the present invention are more durable and require less maintenance than existing flow track systems. In particular, the wheel assemblies of the present invention are self-lubricating, and the polycarbonate wheels are stronger and wider than conventional track wheels to avoid overloading problems and flow problems typically caused by damaged or irregular pallets and cartons. Other features and advantages of the present invention will be apparent to those of skill in the art upon reading and understanding the following detailed description of the invention, drawings and claims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a cut-away top view of a freewheel flow track system according to one embodiment of the invention.

FIG. 2 shows a cut-away side view of the freewheel flow track system of FIG. 1.

FIG. 3 shows a view of a track subassembly of FIG. 2 taken along section B-B.

Continue reading about Freewheel flow track systems...
Full patent description for Freewheel flow track systems

Brief Patent Description - Full Patent Description - Patent Application Claims

Click on the above for other options relating to this Freewheel flow track systems patent application.
###


How KEYWORD MONITOR works... a FREE service from FreshPatents
1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored.
3. Each week you receive an email with patent applications related to your keywords.  
Start now! - Receive info on patent apps like Freewheel flow track systems or other areas of interest.
###


Previous Patent Application:
Holder for a sensor body for a position sensor
Next Patent Application:
Steerable wheel for an agricultural conveyor
Industry Class:
Conveyors, chutes, skids, guides, and ways

###

Design/code © 2009 FreshContext LLC/Freshpatents.com. Website Terms and Conditions - Also read: About this Page
Patent data source: patents published by the United States Patent and Trademark Office (USPTO)
Information published here is for research/educational purposes only (and in conjunction with our Keyword Monitor) and is not meant to be used in place of the full USPTO patent document/images or a comprehensive patent archive search. Complete official applications are on file at the USPTO and often contain additional data/images (Freshpatents is currently text-only). FreshPatents.com is not affiliated with or endorsed by the USPTO or firms/individuals or products/designs/ideas related to listed patents.

FreshPatents.com Support
Thank you for viewing the Freewheel flow track systems patent info.
IP-related news and info


Results in 3.96876 seconds


Other interesting Feshpatents.com categories:
Tyco , Unilever , Warner-lambert , 3m paws