US 9,249,557 B2Granted

Work vehicle

AssigneeHitachi Construction Machinery Co., Ltd.

InventorsHidekazu Moriki, Satoru Kaneko, Takashi Ikimi, Noritaka Ito

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Abstract

When the total value of demanded hydraulic power and demanded traveling power is larger than the sum of the engine power that can be output by an engine (1) and of the discharge power that can be discharged by an electrical storage device (3), the actual power of a hydraulic pump (9) is increased from the value at the time of demand toward the demanded hydraulic power under the constraint of a predetermined limit. While the power of the hydraulic pump is being subjected to the predetermined limit, the actual power of the traveling motor is decreased from the value at the time of demand by a value smaller than the magnitude of the predetermined limit. This prevents worsening of ride comfort attributable to the distribution of power between the hydraulic pump and the traveling motor.

Claims5

Dependent claims

A work vehicle comprising an engine, a hydraulic pump connected mechanically to said engine, a motor generator connected mechanically to said engine, a traveling motor connected electrically to said motor generator, an electrical storage device connected electrically to said motor generator and said traveling motor, and a controller configured to control the power of said hydraulic pump and that of said traveling motor;

wherein said controller is configured to calculate demanded hydraulic power demanded by said hydraulic pump and demanded traveling power demanded by said traveling motor, and
wherein, if a total value of said demanded hydraulic power and said demanded traveling power is larger than a sum of an engine power that can be output by said engine, and a discharge power that can be discharged by said electrical storage device,
said controller is configured to increase an actual power of said hydraulic pump from a value, at a time of demand, toward said demanded hydraulic power, the actual power of said hydraulic pump being incrementally increased, and, while the actual power of said hydraulic pump is being incrementally increased, decrease an actual power of said traveling motor by a value which is equal to or lower than a magnitude of said incremental increase of the actual power of said hydraulic pump.

Dependencies are inferred from the claim text.

Facts

Application: 14/237,014Filed 15 Aug 2012
Priority: JP 2011-17815216 Aug 2011
Published: US 2014/0188320 A13 Jul 2014
Granted: 2 Feb 2016
Term ends: Not estimatedThe source records don’t support an estimate.

Classification50 codes

B60K 6/46
Characterised by the architecture of the hybrid electric vehicle: series type
B60K 6/52
Architecture of the driveline characterised by arrangement or kind of transmission units: driving a plurality of drive axles, e.g. four-wheel drive
B60L 7/14
Dynamic electric regenerative braking: for vehicles propelled by AC motors
B60L 15/2009
For control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed: for braking