US Patent 10422109 Shovel and method of controlling shovel

A shovel includes a turning hydraulic motor, a hydraulic cylinder, a pilot circuit, a hydraulic control valve, a variable throttle, and a controller. The turning hydraulic motor is driven with hydraulic oil supplied from the hydraulic pump to drive a turning body of the shovel to turn. The hydraulic cylinder is driven with the hydraulic oil supplied from the hydraulic pump. The pilot circuit controls a pilot pressure in accordance with the operation of an operation lever. The hydraulic control valve controls the hydraulic oil supplied from the hydraulic pump to the hydraulic cylinder in accordance with the pilot pressure supplied from the pilot circuit. The opening of the variable throttle varies in accordance with the operating state of the operation lever. The controller changes the opening of the variable throttle.