Motor control device for working vehicle
A motor control device for a working vehicle includes: a travel drive device that transmits rotation of a motor to wheels through a torque converter; a first selection device to be operated so as to select one of a power mode and an economy mode; a second selection device that is different from the first selection device; a mode switching device that switches from the economy mode to the power mode if the second selection device is operated in a state where the economy mode has been selected by the first selection device; and a speed restriction device that, when the economy mode is set, restricts a maximum rotational speed of the motor to a lower speed side than that when the power mode is set.
1. A motor control device for a working vehicle, comprising:
a travel drive device that transmits rotation of a motor to wheels through a torque converter;
a first selection device to be operated so as to select one of a power mode and an economy mode;
a second selection device that is different from the first selection device;
a mode switching device that switches from the economy mode to the power mode if the second selection device is operated in a state where the economy mode has been selected by the first selection device; and
a speed restriction device that, when the economy mode is set, restricts a maximum rotational speed of the motor to a lower speed side than that when the power mode is set.
2. A motor control device for a working vehicle according to claim 1 , further comprising:
a determination device that making a decision as to whether a mode switching condition is established in accordance with one of a vehicle state of the working vehicle and an operation on the second selection device, wherein:
the mode switching device switches from the power mode to the economy mode if the determination device makes a decision that a mode switching condition is established in a state where the power mode has been selected by an operation on the second selection device.
3. A motor control device for a working vehicle according to claim 2 , further comprising:
a speed ratio detection device that detects a speed ratio of the torque converter, wherein:
the determination device makes a decision that a mode switching condition is established if the torque converter speed ratio detected by the speed ratio detection device becomes equal to or greater than a predetermined value.
4. A motor control device for a working vehicle according to claim 2 , wherein:
the determination device makes a decision that a mode switching condition is established if the second selection device is operated again in a state where the power mode has been set by an operation on the second selection device.
5. A motor control device for a working vehicle according to claim 2 , wherein:
the determination device makes a decision that a mode switching condition is established if, in a state where a transmission has been set to an automatic shift mode, a shift up signal is output to the transmission.
6. A motor control device for a working vehicle according to claim 2 , wherein:
the determination device makes a decision that a mode switching condition is established if a forward and reverse movement changeover switch, by which an instruction of any of forward, reverse, and neutral of the working vehicle is given, is operated to a neutral position.
7. A motor control device for a working vehicle according to claim 1 , wherein:
the first selection device is an alternate switch provided in a driver cabin; and
the second selection device is a momentary switch provided to a working operation member that outputs a drive instruction to a working actuator in accordance with an operation amount.
8. A motor control device for a working vehicle according to claim 1 , further comprising:
a low-speed instruction device that instructs a speed step to be switched to a low speed side and that is separated from the second selection device.