Lift truck attachment with smart clamp

A method for an electrical controller of a smart clamp load handler of a lift truck with first and second clamp arms configured to be moved by first and second actuators, each of the actuators comprising a rod-side chamber configured for closing of the clamp arms when hydraulic fluid is applied to the rod-side chamber, comprising the steps of:

• (1) reading measurements from sensors, including a base-side pressure sensor providing a series of base-side pressure measurements, a first actuator position sensor providing a series of first actuator position measurements, a second actuator position sensor providing a series of second actuator position measurements;
• (2) recording the measurements in a series of data points, each data point comprising one of the series of first actuator position measurements, one of the series of second actuator position measurements, one of the series of base-side pressure measurements, and an associated one of a series of a time stamps;
• and
• (3) determining when to stop the closing of the clamp arms based on the series of first and second actuator position measurements, and the series of base-side pressure measurements, then signaling an actuator control valve to stop the closing of the clamp arms.

A smart clamp load handler system comprising:

• a first clamp arm and a second clamp arm;
• a first actuator and a second actuator, each of the actuators comprising a rod-side chamber configured for closing of the clamp arms when hydraulic fluid is applied to the rod-side chamber, each of the actuators comprising a base-side chamber configured for opening of the clamp arms when hydraulic fluid is applied to the base-side chamber;
• a distance sensor configured to measure a distance between the first and second clamp arms and provide a series of distance measurements;
• a rod-side pressure sensor configured to provide a series of rod-side pressure measurements;
• a base-side pressure sensor configured to provide a series of base-side pressure measurements;
• an actuator control valve configured to control flow of hydraulic fluid to the actuators;
• and
• an electrical controller configured for determining when to stop the closing of the clamp arms based on the series of distance measurements, and the series of base-side and rod-side pressure measurements, then signaling the actuator control valve to stop the closing of the clamp arms.