NO MORE HAMMERING!
Getting to be that time of the year, you know, when it is too cold to get out of the cab and hammer the hopper bottoms to loosen the material. Hook up a vibrator to the hopper bottom and control the air flow through the solenoid valve. Connect the solenoid to a control box in your cab and eliminate the need to step outside and hammer the hopper bottom.
http://solutionsinmotion.clevelandvibrator.com/