Wheel loader

摘要

Predetermined torque characteristics are obtained by multiplying by a predetermined ratio that is less than 100%, the upper value of engine output torque from the engine output torque line, for at least part of the range of engine rotation speed. Torque upper value information defines the upper value of engine output torque that changes in conformance with vehicle speed and tractive farce. When predetermined conditions for determination are satisfied, an engine output torque control part controls engine output torque based on torque upper value information. The predetermined conditions for determination at the least include that a travel condition is forward travel, that a work condition is laden condition and that a raise operation is being performed by the working machine. When the predetermined conditions for determination are not satisfied the engine output torque control part controls engine output torque based on predetermined torque characteristics.

主权项

1. A wheel loader comprising:
an engine; a travel mechanism configured and arranged to cause a vehicle to ravel by utilizing drive force from the engine; a working machine hydraulic pump configured and arranged to be driven by the engine to discharge hydraulic fluid; a working machine configured and arranged to be driven by the hydraulic fluid discharged from the working machine hydraulic pump; a working machine operating part configured and arranged to operate the working machine; a vehicle speed detection part configured and arrangers to detect vehicle speed; a tractive force detection part configured and arranged to detect tractive force of the vehicle; a memory part configured and arranged to store an output torque line that defines a relationship between engine rotation speed and an upper value of engine output torque, and torque upper value information that defines the upper value of the engine output torque that changes according to the vehicle speed and the tractive force; a travel condition determination part configured to determine whether or not a travel condition of the vehicle is forward travel; a work condition determination part configured to determine whether or not a work condition of the vehicle is laden condition; a raise operation determination part configured to determine whether or not a raise operation is being performed by the working machine operating part in order to raise the working machine; and an engine output torque control part configured to control the engine output torque based on the torque upper value information when conditions for determination at least including that the travel condition is forward travel, that the work condition is laden condition and that the raise operation is being performed are satisfied, and to control the engine output torque based on predetermined torque characteristics obtained by multiplying by a predetermined ratio that is less than 100%, the upper value of the engine output torque in the engine output torque line, for at least a part of a range of the engine rotation speed, when the conditions for determination are not satisfied.