Defense wins games
On Nov. 21, the Tyson Fresh Meats corporate offices played host to an event celebrating the commitment to worker safety in its processing plants. The ceremony saw plaques awarded to all maintenance superintendents – and a plaque for their teams to recognize those who worked on a special project for the development, operation, training, installation and continued research and development of a new band saw that pushes worker safety to a new level.
Hollymatic’s Defender bandsaw represents an important part of the culture shift and investment that has recently taken place, and continues to evolve, throughout the entire company. The saw uses proprietary technology to effectively stop the blade in milliseconds. Not only is the operator protected, but the machine and blade incur no damage.
The saw uses a vision system coupled with color detection gloves to stop the blade when the gloves get too close. The current products in the market for this type of vision system process at roughly 50 to 100 milliseconds.
“What I found was at that speed, when you move a hand in quickly toward the blade, it may or may not catch it,” says Victor Guynn, director of engineering and development at Hollymatic. “So, what I had to do was find a manufacturer that would actually have a high-speed camera fast enough to take an image, process it, and output within 3 milliseconds or less.”
Guynn found his high-speed camera and Hollymatic’s system on the Defender saw will capture an image, decipher and process that image, output to the controls and stop the saw within 3 milliseconds. But the bigger challenge for Guynn was overcoming the wheels’ inertia to stop the blade from moving.
The typical bandsaw uses either cast iron or steel wheels to move the blade. Guynn says the wheels are about 17 lbs. to 20 lbs. each and spin at roughly 1100 RPM. “So, you have to find a big enough motor to stop that inertia once it starts spinning,” he adds. “We were able to find a proprietary motor that we had made for us. Then we also had to couple it with a gearbox to gain more torque.”
Guynn began to test the system with Hollymatic saws equipped with its standard wheels, but they weren’t stopping the blade fast enough. The braking mechanism applies to the lower wheel and allowed the upper wheel to continue moving. After the bottom wheel stopped, the blade would still travel about ten feet due to the upper wheel.
Guynn consulted Chris Rupp, vice president of beef operations at Tyson Foods, about the different possibilities available for faster wheel stoppage.
They found a way to lighten the wheels. “It lowered the inertia by three times,” Guynn says.
The special motor, the gear box and the lighter wheels came together to give Guynn the stop time and consistency he and Tyson Foods wanted to put the saw into action across Tyson fresh meat plants and push momentum in creating a new safety culture.
It was an important addition to the movement in the new direction. “The reason why bandsaws have such a great focus is because the consequences are so quick and severe,” Stouffer says.
