A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
VIBRATING SCREED
A vibrating screed including a screed member, a brushless direct-current motor, a power switching network coupled between a power source and the brushless direct-current motor, and an exciter assembly that vibrates the screed member when torque is received from the motor, and an electric processor. The electric processor is electrically coupled to the motor and the power switching network and is configured to operate the brushless direct-current motor at a selected speed by providing pulse-width modulated signals to the power switching network, the pulse-width modulated signals having a duty ratio, determine a current speed of the brushless direct-current motor, determine whether a difference between the selected speed and the current speed is above a threshold amount, and modify the duty ratio by a predetermined amount when the difference between the selected speed and the current speed is above the threshold amount to continue operating the motor at the selected speed.
VIBRATING SCREED
A vibrating screed including a screed member, a brushless direct-current motor, a power switching network coupled between a power source and the brushless direct-current motor, and an exciter assembly that vibrates the screed member when torque is received from the motor, and an electric processor. The electric processor is electrically coupled to the motor and the power switching network and is configured to operate the brushless direct-current motor at a selected speed by providing pulse-width modulated signals to the power switching network, the pulse-width modulated signals having a duty ratio, determine a current speed of the brushless direct-current motor, determine whether a difference between the selected speed and the current speed is above a threshold amount, and modify the duty ratio by a predetermined amount when the difference between the selected speed and the current speed is above the threshold amount to continue operating the motor at the selected speed.
VIBRATING SCREED
REITER JOSEPH C (author) / RICHARDS DARYL S (author) / HENDRYX CALEB (author)
2024-12-12
Patent
Electronic Resource
English