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, NPI issued a new utility patent: Chain slack adjustment mechanism for parcel sortation systems


NPI was issued a new utility patent on Dec 5th, 2023 for an innovation in reducing the time it takes to restore the chain tension for the parcel sortation systems.

The Importance of Correct Tension Within Chain Driven Sortation Systems:

Conventional chain driven sortation systems use two chains spanning between a motor driven axle with chain sprockets on one end of the machine, and a second non-powered idler axle also with chain sprockets. These axels are usually solid and span across the full width of the transport. The chains must remain in tension between the driven and idler axles for the sorter to safely carry the parcel transport slats and otherwise function properly. The solid drive axle to solid idler axle arrangement used in parallel chain driven systems, such as used in parcel sorting systems, significantly contributes to chain wear. This type of wear is due to typical uneven parcel weight loading on the chain driven slats, which causes a diagonal torqueing action of the chains against the sprockets. This twisting motion of the chains against the sprockets aggravates chain wear, which in turn accelerates the need for chain length adjustment.

The Purpose:

Due to such wear, along with normal wear and tear, the chains increase in length such that the chains must be manually shortened to eliminate excessive chain slack by removing slats and chain links from the chains on both sides of the sorter. Manually shortening these chains is a very time consuming process, which causes a loss of the sorter’s production time and the associated loss of considerable item processing profits. Although great strides have been made in the area of chain driven sortation systems, significant shortcomings remained.

NPI’s Patented Solution:

NPI’s chain slack adjustment mechanism makes it quick and easy to adjust the excessive slack on the chain caused from wear and tear and normal use of a parcel sorting system. With the patented mechanism, technicians can restore the chain to the correct length and tension quickly, solving the issue of extended periods of system downtime during maintenance. Without NPI’s patented chain slack adjustment mechanism, similar parcel sorting systems require more time and labor to manually adjust the chain, and restore the sorting system to it’s fullest potential.

All new NPI Xstream Shoe Sorting systems include the patented chain slack adjustment mechanism. Click here for more information about the Xstream.