Hitachi has launched two new rigid frame haul trucks, the EH3500AC-3 and the EH4000AC-3.
The vehicles are designed with nominal payloads of 181 tonnes and 220 tonnes respectively, and are equipped with AC drive systems.
According to the company the new vehicles feature improved sensing and control equipment that provide in-depth information on the vehicle and driving conditions.
“The result is the Hitachi Drive Control System reduces tyre slippage on acceleration and tyre lock-up during braking, and prevents chassis oscillation in a front-rear direction, and tyre skid whilst steering,” Hitachi said in a company statement.
Its AC-drive system, which has high load-responsive IGBT inverters, also features drive control software that was jointly developed with other Hitachi Group companies for greater travel motor speed and torque control.
These two models also feature electric brakes that are activated during downhill driving, which means the trucks can be normally operated using two pedals, one for acceleration and one for the brakes. This creates easier overall operability and alleviates operator fatigue.
Since these trucks do not require the use of mechanical brakes during normal driving, it means smoother deceleration as well as less frequent maintenance for the mechanical brakes.
The trucks have been designed with a wide-berth cab, which is capable of housing two full-size seats and features a large LCD display at the base of the handle.
The display is in clear view and quickly provides the operator with information and warnings on drive operations such as travelling speed, engine turnover and hauling performance.
In addition, the multilingual display allows users to view information and warnings in their own language, contributing to improved serviceability and safety.
Hitachi located the levers and switches for operating the body in the centre console, making it possible to operate the body with one hand.
The mainframe’s structural design, including the cab support, is improved and fortified based on operating information Hitachi gathered on conventional models being used around the world.
The company added a temperature sensor to the bearing area of the alternator and drive motor, which are the main components of the AC-drive system.
An alarm sounds when the sensor detects abnormal heat emission and restricts driving operations to prevent sudden damage to the machine.
Improvements were made to the nominal payload measurement system to increase the reliability of production volume measurements at mining sites.
Measurement errors have been reduced by reflecting changes in fuel weight within the fuel tank into the nominal payload.
ROPS and FOPS are built into every truck cab as a standard safety requirement to withstand the impact of falling objects or a truck rollover.
Other standard safety features include two mirrors with front and rear view cameras to provide extensive truck perimeter visibility, high width truck access stairways and four engine stop switches located outside the cab to allow the operator to turn off the engine in an emergency situation during maintenance.
Ease of maintenance has also been a focus in the new trucks design.
The evacuator exhaust valve for the engine suction filter and electric grease pump are among the new features added to further improve daily maintenance.
Other standard features for maintenance include a trailing arm front suspension that permits strut removal without tyre removal, a centralised auto-grease system accessible from the ground, a battery and relay box located in the front bumper for easy access, and a maintenance deck in the rear of the cab.
Operators outside of the US will also have choice of engines, between the standard feature Cummins engine and one by MTU Friedrichshafen GmbH.
This latest release of the two rigid frame haul trucks models completes the manufacturers range for its EH AC-3 series.