Custom Motorized Cart in the Packaging Industry
Electro Kinetics Technologies recently completed a custom project for the 5th largest corrugated packaging company in the U.S. and the world’s largest, privately-held 100% recycled paper and packaging company. In addition to containerboard mills, corrugating facilities and sheet conversion operations in more than 25 states and Mexico, the company’s Retail Specialties Division produces cushioning, void fill, and other packaging accessories.
One of the customer’s Retail Specialties facilities produces “bubble-wrap” commonly used as cushioning material in packaging operations. In the final step of the production process, the bubble-wrap sheet is wound into large 48” diameter by 60” high rolls, each weighing 75 lbs. The cumbersome and heavy rolls are manually removed from the winding machine by two employees and stacked on pallets for storage and transport. The rolls are stacked two-high, requiring the second roll to be lifted over 5-feet to be placed on top of the first roll. The customer asked Electro Kinetics Technologies to develop a custom motorized cart solution for handling and transporting the bubble-wrap rolls that would reduce employee fatigue and minimize the risk of back and other musculoskeletal injuries.
Working with the customer’s operations group, a motorized cart was designed to mechanically remove the bubble-wrap rolls from the winding machine, transport them to a storage area, and stack them on pallets. The cart has a built-in scissor-lift for vertical travel, plus a rotating cradle assembly for holding and maneuvering the rolls.
With the scissor-lift in its lowered position and the cradle positioned horizontally, the cart is driven under a finished roll on the winding machine’s mandrel and a “cradle lip mechanism” is raised at the end of the cradle. The cart is then backed away from the winding machine, with the raised lip pulling the roll off the mandrel and onto the cart’s cradle. Both the raised lip and a clamp mechanism hold the roll securely on the cradle.
After transporting the roll to the storage area, and with the scissor-lift still in its lowest position, a built-in actuator is used to raise the cart’s cradle to a vertical position (the raised lip and clamp hold the roll on the cradle). The cart is then driven forward positioning the roll over a pallet where the lip is lowered, depositing the first roll onto the pallet in an upright position. The motorized cart then returns to the winding machine to unload the next roll.
After returning to the storage area with the second roll, the cart’s scissor-lift is raised to its highest position. The cradle is then raised to a vertical position with the cradle lip and clamp holding the roll upright on the cradle. The cart is driven forward until the second roll is directly over the first roll and the lift-table is lowered slightly. The cradle clamp is released allowing the cart to be backed away with the second roll left standing on top of the first roll.
In addition to the scissor-lift and rotating cradle assembly, the motorized cart included a transaxle drive system, onboard maintenance-free batteries and charger, and a thumb-wheel style user-interface control with dual speed range. Safety features incorporated into the design included:
- A requirement for simultaneous operation of two switches located 8” apart on the cart’s handle when raising or lowering the cradle assembly – keeps the operator’s hands away from potential pinch-points.
- Safety skirting around the scissor-lift mechanism.
- An emergency stop “belly” button located on the user-interface control.
- A limit switch that restricts the cart’s speed when the scissor-lift is raised.
- An electro-mechanical parking brake
- A warning horn
For more information on custom motorized solutions, and Electro Kinetic Technologies’ engineering services, visit our contact page and consult with one of our experts.