Work Vehicle

• US 20130225364A1
• Filed: 08/27/2012
• Published: 08/29/2013
• Est. Priority Date: 12/26/2011
• Status: Abandoned Application

• Current Assignee: Kubota Corporation
• Original Assignee: Kubota Corporation
• Inventors: Tanimura, Issei, Ono, Akiyoshi, Kuroshita, Yoshihiko, Shinkai, Atsushi
• Application Number:
  US13/595,366
• Publication Number:
  US 20130225364A1
• Time in Patent Office: Days
• US Class Current: 477/52
• CPC Class Codes: B60K 2310/20 Operator actuated switches or levers for cruise control or speed limiting systems
• CPC Class Codes: B60K 2310/24 Speed setting methods
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/103 of fluid type
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: E02F 9/2066 of the type combustion engines
• CPC Class Codes: E02F 9/2079 Control of mechanical transmission for hydrostatic transmission or hydraulic torque converter E02F9/2253
• CPC Class Codes: E02F 9/2253 Controlling the travelling speed of vehicles, e.g. adjusting travelling speed according to implement loads, control of hydrostatic transmission
• CPC Class Codes: F16H 39/00 Rotary fluid gearing using pumps and motors of the volumetric type, i.e. passing a predetermined volume of fluid per revolution control of exclusively fluid gearing F16H61/38
• CPC Class Codes: F16H 61/431 Pump capacity control by electro-hydraulic control means, e.g. using solenoid valves
• CPC Class Codes: F16H 61/47 for achieving a target output speed

Abstract

A work vehicle includes a target rotational speed calculation section for obtaining a target rotational speed of an engine corresponding to an operation of an accelerator, a high-speed-rotation rotational speed setting section for the engine rotational speed, an engine rotational speed control section for controlling the engine rotational speed, and a high-speed-rotation instruction operation section for providing a high-speed-rotation instruction for the engine rotational speed. The engine section effects an accelerator control for controlling the engine rotational speed to the target rotational speed when the high-speed-rotation instruction operation section does not so provide. The engine rotational speed control section effects a high-speed-rotation control for controlling the engine rotational speed to the higher of the target rotational speed and the high-speed-rotation rotational speed when the rotational speed instruction operation section provides the high-speed-rotation instruction.

Claims

1. A work vehicle comprising:

an engine;

a hydraulic pump driven by the engine for feeding work oil to a work implement connected to a traveling vehicle body;

a target rotational speed calculation section for obtaining a target rotational speed of the engine corresponding to an operation of an accelerator operation section;

a high-speed-rotation rotational speed setting section capable of setting a high-speed-rotation rotational speed for the engine rotational speed;

an engine rotational speed control section for controlling the engine rotational speed; and

a manual operation type, high-speed-rotation instruction operation section for providing a high-speed-rotation instruction for the engine rotational speed;

wherein the engine rotational speed control section effects an accelerator control for controlling the engine rotational speed to the target rotational speed when the high-speed-rotation instruction operation section does not provide the high-speed-rotation instruction, whereas the engine rotational speed control section effects a high-speed-rotation control for controlling the engine rotational speed to whichever higher one of the target rotational speed and the high-speed-rotation rotational speed when the high-speed-rotation rotational speed instruction operation section provides the high-speed-rotation instruction.

2. The work vehicle according to claim 1, further comprising:

a traveling speed changer device capable of speed changing operations in response to an operation of a speed changer section; and

a restraint section for restraining execution of the high-speed-rotation control by the engine rotational speed control section in case the speed range of the speed changer device is switched to a high speed range.

3. The work vehicle according to claim 1, wherein in the high-speed-rotation control, the engine rotational speed control section increases the engine rotational speed with setting an increasing speed of the engine rotational speed slower than a set increasing speed.

4. The work vehicle according to claim 1, further comprising:

a vehicle speed hold device for holding the vehicle speed of the traveling vehicle body in case the engine rotational speed control section executes the high-speed-rotation control.

5. The work vehicle according to claim 4, wherein:

the work vehicle further comprises a hydraulic stepless speed changer device capable of speed change through variable adjustment of a swash plate angle; and

the vehicle speed hold device holds the vehicle speed of the traveling vehicle body through control of the swash plate angle of the hydraulic stepless speed changer device.

6. The work vehicle according to claim 1, wherein the work implement is a front loader;

and

the vehicle further comprises an operation lever for operating the front loader, and the operation lever includes, at its grip portion, a switch as the high-speed-rotation instruction operation section.