Engine control apparatus for work machine and engine control method thereof

Patent metadata

Field	Value
Publication number	US-9494169-B2
Application number	US-201314344728-A
Country	US
Kind code	B2
Filing date	May 31, 2013
Priority date	May 31, 2013
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

The present invention includes an information generator to set a lever manipulation amount total sum decrease flag during a period when a lever manipulation amount total sum is decreasing, a first processor to process an engine actual output, an engine actual output latching function block to output the maximum value of the engine actual output until the present during a period in which a lever manipulation amount total sum decrease flag is not set, and output the present engine actual output during a period in which the flag is set, a second processor to output an engine target output based on the engine output, and a controller to control the engine speed under limitation of the engine target output.

First claim

The invention claimed is:

1. An engine control apparatus of a work machine including an engine, a work apparatus driven by at least engine power and a manipulating lever which operates at least an operation of the work apparatus, the apparatus comprising:
an engine output decrease allowing information generating unit configured to generate an engine output decrease allowing information which allows decrease in an engine output during a period in which a lever manipulation amount total sum of the manipulating lever is decreasing the lever manipulation amount total sum being at least based on the operation of the work apparatus;
an engine actual output processing unit configured to process an engine actual output based on engine torque and an engine speed;
a latching function unit configured to keep and output a maximum value of the engine actual output while the engine output decrease allowing information is not generated, and output a present value of the engine actual output while the engine output decrease allowing information is generated;
an engine target output processing unit configured to process and output an engine target output based on an engine output which is output by the latching function unit; and
an engine controller configured to control the engine speed under limitation of the engine target output,
wherein the engine output decrease allowing information generating unit includes a hysteresis processing unit configured to carry out hysteresis processing in which the lever manipulation amount total sum is determined to have decreased so that the engine output decrease allowing information generating unit starts generating the engine output decrease allowing information when an amount of change in a decreasing-direction of the lever manipulation amount total sum is not smaller than a predetermined amount, and the lever manipulation amount total sum is determined to have increased so that the engine output decrease allowing information generating unit stops generating the engine output decrease allowing information when an amount of change in an increasing-direction of the lever manipulation amount total sum is not smaller than, a predetermined amount,
wherein the engine output decrease allowing information generating unit is configured not to generate the engine output decrease allowing information when a pump pressure exceeds a predetermined high pressure threshold.

2. The engine control apparatus of a work machine according to claim 1 , further comprising
a single touch power-up button configured to output a single touch power-up signal which gives a command to temporarily increase the engine output, wherein the engine output decrease allowing information generating unit is configured not to generate the engine output decrease allowing information during a period when the single touch power-up button signal is input.

3. The engine control apparatus of a work machine according to claim 1 , wherein the engine target output processing unit is configured not to carry out processing in a direction in which an engine target output increases when the engine output decrease allowing information is generated.

4. The engine control apparatus of a work machine according to claim 1 , wherein the work machine includes an electric swing mechanism.

5. An engine control method for a work machine including an engine, a work apparatus driven by at least engine power, and a manipulating lever which operates at least an operation of the work apparatus, the method comprising:
an engine output decrease allowing information generating step in which an engine output decrease allowing information which allows decrease in an engine output during a period when a lever manipulation amount total sum of a manipulating lever is decreasing is generated, the lever manipulation amount total sum being at least based on the operation of the work apparatus;
an engine actual output processing step in which an engine actual output is processed based on engine torque and an engine speed;
a latching function step in which a maximum value of the engine actual output is kept and output while the engine output decrease allowing information is not generated, and a present value of the engine actual output is output while the engine output decrease allowing information is generated;
an engine target output processing step in which an engine target output is processed and output based on an engine output which is output by the latching function step; and
an engine control step in which the engine speed is controlled under limitation of the engine target output,
wherein the engine output decrease allowing information generating unit includes a hysteresis processing unit configured to carry out hysteresis processing in which the lever manipulation amount total sum is determined to have decreased so that the engine output decrease allowing information generating step starts generating the engine output decrease allowing information when an amount of change in a decreasing-direction of the lever manipulation amount sum is not smaller than predetermined amount, and the lever manipulation amount total sum is determined to have increased so that the engine output decrease allowing information generating step stops generating the engine output decrease allowing information when an amount of change in an increasing-direction of the lever manipulation amount total sum is not smaller than a predetermined amount,
wherein the engine output decrease allowing information generating unit is configured not to generate the engine output decrease allowing information when a pump pressure exceeds a predetermined high pressure threshold.

6. The engine control method for a work machine according to claim 5 , wherein the work machine includes an electric swing mechanism.

7. An engine control apparatus of a work machine including an engine, a work apparatus driven by at least engine power and a manipulating lever which operates at least an operation of the work apparatus, the apparatus comprising:
an engine output decrease allowing information generating unit configured to generate an engine output decrease allowing information which allows decrease in an engine output during a period in which a lever manipulation amount total sum of the manipulating lever is decreasing;
an engine actual output processing unit configured to process an engine actual output based on engine torque and an engine speed;
a latching function unit configured to keep and output a maximum value of the engine actual output while the engine output decrease allowing information is not generated, and output a present value of the engine actual output while the engine output decrease allowing information is generated;
an engine target output processing unit configured to process and output an engine target output based on an engine output which is output by the latching function unit; and
an engine controller configured to control the engine speed under limitation of the engine target output,
wherein the engine output decrease allowing information generating unit includes a processing unit configured not to generate the engine output decrease allowing information when a pump pressure exceeds a predetermined high pressure threshold, and configured to generate the engine output decrease allowing information based on the lever manipulation amount total sum of the manipulating lever during the period in which the lever manipulation amount total sum of the manipulating lever is decreasing when the pump pressure does not exceed the predetermined high pressure threshold.

8. The engine control apparatus of a work machine according to claim 7 , further comprising
a single touch power-up button configured to output a single touch power-up s

Assignees

• Komatsu Mfg Co Ltd

Inventors

• Murakami Kentaro
• Kawaguchi Tadashi

Classifications

• F15B2211/20523

  Internal combustion engine · CPC title

• F15B2211/72

  having locking means · CPC title

• F15B21/082

  with different modes · CPC title

• F15B2211/6333

  representing a state of the pressure source, e.g. swash plate angle · CPC title

• E02F9/2066

  of the type combustion engines · CPC title