IP Library Granted Patent US 8,777,808
Granted Patent B2
US 8,777,808 · App. 13/377,973 · Granted Jul 15, 2014

Working vehicle control apparatus

Inventors: Koji Hyodo (Kasumigaura, JP); Hiroki Nakazono (Ryugasaki, JP); Hirofumi Oouchi (Toride, JP); Atsushi Shimazu (Toride, JP)
Assignee: Hitachi Construction Machinery Co., Ltd.
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Quick Facts
Patent No.
US 8,777,808
App. No.
13/377,973
Granted
Jul 15, 2014
Kind
B2
Abstract

A working vehicle control apparatus includes: a selection device that selects a power mode or an economy mode; a determination device that determines whether or not a speed restriction condition and a load pressure have been established; an engine rotational speed restriction device that restricts a maximum rotational speed of the motor upon selection of the economy mode to a lower speed side than a maximum rotational speed of the motor upon selection of the power mode when it is determined that the speed restriction condition has been established; and a vehicle speed restriction device that restricts a maximum vehicle speed upon selection of the economy mode to a lower speed side than a maximum vehicle speed upon selection of the power mode when it is determined that a speed restriction condition has not been established.

Claims (17)

1. A working vehicle control apparatus, comprising:

a rotational speed control device that controls a rotational speed of a motor in accordance with an operation amount of an accelerator pedal;

a hydraulic pump that is driven by the motor to supply a driving pressure to a working actuator on which a reaction force in accordance with a travel driving force acts;

a travel drive device that transmits rotation of the motor to wheels through a torque converter;

a speed ratio detection device that detects a speed ratio of an input shaft and an output shaft of the torque converter;

a load pressure detection device that detects a load pressure of the hydraulic pump;

a selection device that selects one of a power mode and an economy mode;

a determination device that determines whether or not a speed restriction condition in which a speed ratio detected by the speed ratio detection device is equal to or less than a predetermined value and a load pressure detected by the load pressure detection device is equal to or greater than a predetermined value has been established;

an engine rotational speed restriction device that restricts a maximum rotational speed of the motor upon selection of the economy mode to a lower speed side than a maximum rotational speed of the motor upon selection of the power mode when it is determined by the determination that the speed restriction condition has been established; and

a vehicle speed restriction device that restricts a maximum vehicle speed upon selection of the economy mode to a lower speed side than a maximum vehicle speed upon selection of the power mode when it is determined by the determination device that a speed restriction condition has not been established.

2. A working vehicle control apparatus according to claim 1 , further comprising:

a speed change device that changes a transmission speed step in accordance with a speed ratio detected by the speed ratio detection device;

a vehicle speed detection device that detects a vehicle speed; and

a speed change control device that permits the speed change device to shift up in a condition where a vehicle speed detected by the vehicle speed detection device is equal to or greater than a predetermined value, wherein:

the speed change control device permits shift up in a condition where a detected vehicle speed is equal to or greater than a first predetermined value upon selection of the economy mode and permits shift up in a condition where a detected vehicle speed is equal to or greater than a second predetermined value, which is greater than the first predetermined value, upon selection of the power mode.

3. A working vehicle control apparatus according to claim 2 , wherein:

the speed change control device permits the shift up in a further condition where it is determined by the determination device that a speed restriction condition has not been established.

Assignments (3)
MERGER Recorded Aug 19, 2019
From: KCM CORPORATION
To: HITACHI CONSTRUCTION MACHINERY CO., LTD.
Reel/Frame 050088/0068 →
MERGER Recorded Feb 24, 2017
From: HITACHI CONSTRUCTION MACHINERY CO., LTD.
To: KCM CORPORATION
Reel/Frame 041806/0087 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 14, 2012
From: HYODO, KOJI; NAKAZONO, HIROKI; OOUCHI, HIROFUMI; SHIMAZU, ATSUSHI
To: HITACHI CONSTRUCTION MACHINERY CO., LTD.
Reel/Frame 027864/0167 →
Priority Claims (1)
JP 2009-146198 · Jun 19, 2009 · national
Continuity (1)
Related Publication 20120100959A1 · Apr 26, 2012