A load weight measuring device for a multi-stage mast forklift truck

摘要

A load weight measuring device for a multi-stage mast forklift truck has a mast assembly (3), an oil passage, a flow regulator valve, a pressure sensor, a detecting device (28), a memory, a selector, and a calculator. The mast assembly (3) has a lift bracket (6) for receiving a load weight, a multi-stage mast unit having masts (3A,3B), and a multi-stage lift cylinder unit having lift cylinders (4A,4B,7) each having an oil chamber for raising the lift bracket (6) along the masts (3A,3B). Hydraulic oil flows in the oil passage. The pressure sensor detects a pressure of hydraulic oil and outputs a pressure signal. The detecting device (28) detects a state which stage of the lift cylinder (4A,4B) raises the lift bracket (6) and outputs a detection signals. The memory stores predetermined parameters from which the selector selects the parameter based on the detection signal. The calculator calculates the load weight based on the selected parameter and the pressure signal.