Work vehicle and control method for work vehicle

• US 10,124,805 B2
• Filed: 07/31/2014
• Issued: 11/13/2018
• Est. Priority Date: 07/31/2014
• Status: Active Grant

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Kou, Ryuuen, Nishijima, Akiharu, Kondou, Shinya
• Primary Examiner(s): Lee, Tyler J
• Application Number:
  US15/329,008
• Publication Number:
  US 20170210386A1
• Time in Patent Office: 1,566 Days
• Field of Search: 701 2, 701 50
• CPC Class Codes: B60K 17/35 including arrangements for suppressing or influencing the power transfer, e.g. viscous clutches differential gearing with locking devices F16H48/20
• CPC Class Codes: B60K 28/16 responsive to, or preventing, skidding of wheels brake control systems for vehicle drive stability B60T8/1755; arrangements responsive to a speed condition for adjusting wheel braking force B60T8/32; control of vehicle driving stability otherwise than by controlling the propulsion unit only B60W30/02; preventing wheel slippage by reducing power in rail vehicles B61C15/00
• CPC Class Codes: B60P 3/00 Vehicles adapted to transport, to carry or to comprise special loads or objects ambulances or other vehicles with special provisions for transporting patients or disabled persons, or their personal conveyances A61G3/00; hearses A61G21/00; fire-fighting land vehicles A62C27/00; refuse-collecting vehicles B65F3/00, B65F7/00; snow-removing vehicles E01H; armoured or armed vehicles F41H7/00; self-propelled mine-clearing vehicles F41H11/16
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• CPC Class Codes: B60T 7/18 operated by wayside apparatus
• CPC Class Codes: B60T 8/174 characterised by using special control logic, e.g. fuzzy logic , neural computing
• CPC Class Codes: B60T 8/175 Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 2300/125 Heavy duty trucks
• CPC Class Codes: B60W 2300/17 Construction vehicles, e.g. graders, excavators
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/26 Wheel slip
• CPC Class Codes: B60W 2520/263 Slip values between front and rear axle
• CPC Class Codes: B60W 2520/28 Wheel speed
• CPC Class Codes: B60W 2556/45 External transmission of data to or from the vehicle
• CPC Class Codes: B60W 2710/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2710/18 Braking system
• CPC Class Codes: B60W 2710/182 Brake pressure, e.g. of fluid or between pad and disc
• CPC Class Codes: B60W 2720/28 : Wheel speed
• CPC Class Codes: B60W 30/00 : Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
• CPC Class Codes: B60W 30/02 : Control of vehicle driving stability
• CPC Class Codes: B60W 30/18172 : Preventing, or responsive to skidding of wheels
• CPC Class Codes: B60W 30/188 : Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: G01S 13/931 : of land vehicles
• CPC Class Codes: G08G 1/096725 : where the received information generates an automatic action on the vehicle control
• CPC Class Codes: G08G 1/096741 : where the source of the transmitted information selects which information to transmit to each vehicle
• CPC Class Codes: G08G 1/096775 : where the origin of the information is a central station
• CPC Class Codes: G08G 1/16 : Anti-collision systems road vehicle drive control systems for predicting or avoiding probable or impending collision otherwise than by control of a particular sub-unit B60W30/08
• CPC Class Codes: G08G 1/165 : for passive traffic, e.g. including static obstacles, trees
• CPC Class Codes: G08G 1/166 : for active traffic, e.g. moving vehicles, pedestrians, bikes
• CPC Class Codes: G08G 1/20 : Monitoring the location of vehicles belonging to a group, e.g. fleet of vehicles, countable or determined number of vehicles
• CPC Class Codes: H05K 999/99 : dummy group

Abstract

A work vehicle includes: an engine; a plurality of drive wheels driven by the engine; and an operation controller executes first drive force control that brakes a slipping drive wheel out of the plurality of drive wheels and executes second drive force control that reduces output of the engine in accordance with the slip ratio of the slipping drive wheel during execution of the first drive force control.

Claims

1. A dump truck for traveling in a mine comprising:

an engine;

a vessel;

a plurality of drive wheels driven by the engine; and

an operation controller configured to execute first drive force control that brakes a slipping drive wheel out of the plurality of drive wheels and also configured to execute second drive force control that reduces output of the engine in accordance with a slip ratio of the slipping drive wheel during execution of the first drive force control,

wherein at a time of performing the second drive force control, the operation controller subtracts a correction accelerator position acquired in accordance with the slip ratio of the slipping drive wheel from a target accelerator position of an accelerator acquired in accordance with a target vehicle speed and an actual vehicle speed.

2. The dump truck according to claim 1, wherein the operation controller executes the second drive force control in a case where an actual vehicle speed of the dump truck is less than a first vehicle speed threshold and also a speed difference between the drive wheel and a driven wheel included in the dump truck is continuously kept at a speed difference threshold or more.

3. The dump truck according to claim 2, wherein the operation controller finishes the second drive force control currently executed in a case where the first drive force control is finished or the actual vehicle speed of the dump truck is equal to or more than a second vehicle speed threshold that is larger than the first vehicle speed threshold during execution of the second drive force control.

4. The dump truck according to claim 1, further comprising a communication device configured to communicate with outside of the dump truck,

wherein the operation controller obtains a target vehicle speed of the dump truck from the communication device, performs control such that the actual vehicle speed of the dump truck becomes the target vehicle speed.

5. A dump truck including an engine and a plurality of drive wheels driven by the engine, comprising:

a communication device configured to communicate with outside of the dump truck; and

an operation controller configured to obtain a target vehicle speed of the dump truck from the communication device and perform control such that an actual vehicle speed of the dump truck becomes the target vehicle speed,

wherein

the operation controller executes first drive force control that brakes a slipping drive wheel out of the plurality of drive wheels such that a slip ratio of the slipping drive wheel becomes a target value of the slip ratio of the drive wheel, and further executes second drive force control that reduces output of the engine in accordance with the slip ratio of the slipping drive wheel during execution of the first drive force control, and

at a time of performing the second drive force control, the operation controller subtracts a correction accelerator position acquired in accordance with the slip ratio of the slipping drive wheel from a target accelerator position of an accelerator acquired in accordance with the target vehicle speed and the actual vehicle speed.

6. A control method for a dump truck including an engine and a plurality of drive wheels driven by the engine, comprising:

acquiring slip ratios of the plurality of drive wheels;

executing drive force control that brakes a slipping drive wheel out of the plurality of drive wheels;

reducing output of the engine in accordance with a slip ratio of the slipping drive wheel in a case where a vehicle speed of the dump truck is less than a vehicle speed threshold and a speed difference between the drive wheel and a driven wheel included in the dump truck is continuously kept at a speed difference threshold or more during execution of the drive force control; and

subtracting a correction accelerator position acquired in accordance with the slip ratio of the slipping drive wheel from a target accelerator position of an accelerator acquired in accordance with a target vehicle speed and an actual vehicle speed.