WORK MACHINE

• US 20140165548A1
• Filed: 05/10/2012
• Published: 06/19/2014
• Est. Priority Date: 05/18/2011
• Status: Active Grant

• Current Assignee: Hitachi Construction Machinery Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi Construction Machinery Company Limited (Hitachi, Ltd.)
• Inventors: Satake, Hidetoshi, Edamura, Manabu, Ooki, Takatoshi, Nishikawa, Shinji, Shibata, Kouichi
• Granted Patent: US 9,574,324 B2
• Time in Patent Office: Days
• US Class Current: 60/420
• CPC Class Codes: B60K 17/10 of fluid gearing of fluid clutches B60K17/02
• CPC Class Codes: B60K 2001/0416 Arrangement in the rear part of the vehicle
• CPC Class Codes: B60K 25/00 Auxiliary drives B60K16/00 takes precedence; arrangements of tyre-inflating pumps mounted on vehicles B60C23/10; driving tyre-inflating pumps B60C; driving engine auxiliaries F02B
• CPC Class Codes: B60K 25/04 from static or dynamic pressure or vacuum, developed by the engine
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60K 7/0015 the motor being hydraulic
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60Y 2200/41 Construction vehicles, e.g. graders, excavators
• CPC Class Codes: B60Y 2200/412 Excavators
• CPC Class Codes: B60Y 2200/415 Wheel loaders
• CPC Class Codes: E02F 9/123 Drives or control devices specially adapted therefor E02F9/125 and E02F9/128 take precedence
• CPC Class Codes: E02F 9/2075 of the hybrid type for vehicles in general B60W20/00
• CPC Class Codes: E02F 9/2095 Control of electric, electro-mechanical or mechanical equipment not otherwise provided for, e.g. ventilators, electro-driven fans control of hydraulic driven equipment E02F9/22
• CPC Class Codes: E02F 9/226 Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
• CPC Class Codes: E02F 9/2296 Systems with a variable displacement pump
• CPC Class Codes: E02F 9/267 Diagnosing or detecting failure of vehicles
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

A work machine includes a swing hydraulic motor and a swing electric motor for driving an upper swing structure. A capacitor supplies electricity to the swing electric motor and an operating device outputs through one operation, an operating signal for concurrently operating the swing hydraulic motor and the swing electric motor. A main controller switches between a hydraulic-alone drive mode and an electric-alone drive mode, the hydraulic-alone drive mode being a mode to drive only the swing hydraulic motor selected from the swing hydraulic motor and the swing electric motor when the operating device is operated, the electric-alone drive mode being a mode to drive only the swing electric motor selected from the swing hydraulic motor and the swing electric motor when the operating is operated. Therefore, the actuator that malfunctions can easily be specified among the plurality of mounted actuators.

Claims

1. A work machine comprising:

two or more actuators for driving a common drive object, the actuators including at least one hydraulic actuator and one electric actuator;

a hydraulic pump for supplying pressurized fluid to the hydraulic actuator;

an electric power supply device for supplying electricity to the electric actuator;

an operating device for outputting, through a single operation, an operating signal for concurrently operating the hydraulic actuator and the electric actuator;

a controller for switching between a hydraulic-alone drive mode and an electric-alone drive mode, the hydraulic-alone drive mode being a mode to drive only the hydraulic actuator among the two or more actuators to thereby drive the drive object when the operating device is operated, the electric-alone drive mode being a mode to drive only the electric actuator among the two or more actuators to thereby drive the drive object when the operating device is operated; and

an input device used by an operator to select any one of the plurality of drive modes including the hydraulic-alone drive mode and the electric-alone drive mode;

wherein if the hydraulic-alone drive mode or the electric-alone drive mode is selected with the input device, the controller switches the drive mode of the drive object in accordance with the drive mode thus selected.

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

a pair of hydraulic ports installed in a line for supplying pressurized fluid to the hydraulic actuator and a line for discharging pressurized fluid from the hydraulic actuator, respectively; and

a measurement part for attaching thereto a measuring device for measuring at least one of a value and a phase of an electrical current flowing in an electric power line connected to the electric actuator and a value of voltage of the electrical power line.

3. The work machine according to claim 1, further comprising:

first sensors for outputting pressure before and behind the hydraulic actuator;

a second sensor for outputting a state of the electric current of the electric power line connected to the electric actuator; and

a connection terminal connection with display means for displaying at least one of output values of the first sensors and the second sensor at the time of selection of the hydraulic-alone drive mode or the electric-alone drive mode.

4. The work machine according to claim 1,

line communicating means for allowing a line for supplying pressurized fluid to the hydraulic actuator to communicate with a line for discharging pressurized fluid from the hydraulic actuator, at the time of selection of the electric-alone drive mode;

wherein the controller outputs a torque-zero signal as an operating signal for the electric actuator at the time of selection of the hydraulic-alone drive mode.

5. The work machine according to claim 2, further comprising:

a pressure measuring device mounted to the pair of hydraulic ports, the pressure measuring device outputting the pressure before and behind the hydraulic actuator; and

an electric measuring device mounted to the measurement part, the electric measuring device outputting the current value of the electric power line connected to the electric actuator.

6. The work machine according to claim 4, further comprising:

a sensor for outputting displacement of the hydraulic actuator or the electric actuator; and

a connection terminal for connection with display means for displaying an output value of the sensor at the time of selection of the hydraulic-alone drive mode or the electric-alone drive mode.

7. The work machine according to claim 1, further comprising:

sensors for outputting signals representing various states of the hydraulic actuator and the electric actuator;

a storage unit having stored therein reference values of the signals of the various states each serving as a reference for detecting the malfunction of the hydraulic actuator and the electric actuator, the reference values being values of the signals of the various states encountered when a predetermined operation is performed through the operating device in the case where the hydraulic-alone drive mode or the electric-alone drive mode is selected; and

a connection terminal for connection with display means for displaying a screen on the basis of a display signal outputted from the controller;

wherein if the hydraulic-alone drive mode or the electric-alone drive mode is selected, the controller outputs to the connection terminal a display signal for requesting the predetermined operation of an operator via the operating device, and outputs to the connection terminal a display signal for displaying the relationship between the reference value and an output value of the sensor encountered when the operating device is operated based on the display signal.

8. A work machine comprising:

two or more actuators for driving a common drive object, the actuators including at least one hydraulic actuator and one electric actuator;

a hydraulic pump for supplying pressurized fluid to the hydraulic actuator;

an electric power supply device for supplying electricity to the electric actuator;

an operating device for outputting, through a single operation, an operating signal for concurrently operating the hydraulic actuator and the electric actuator;

a controller for switching between a combined drive mode and an electric-alone drive mode, the combined drive mode being a mode to drive the two or more actuators to thereby drive the drive object when the operating device is operated, the electric-alone drive mode being a mode to drive only the electric actuator among the two or more actuators to thereby drive the drive object when the operating device is operated; and

an input device used by an operator to select any one of the plurality of drive modes including the combined drive mode and the electric-alone drive mode;

wherein if the combined drive mode or the electric-alone drive mode is selected with the input device, the controller switches the drive mode of the drive object in accordance with the drive mode thus selected.

9. A work machine comprising:

two or more actuators for driving a common drive object, the actuators including at least one hydraulic actuator and one electric actuator;

a hydraulic pump for supplying pressurized fluid to the hydraulic actuator;

an electric power supply device for supplying electricity to the electric actuator;

an operating device for outputting, through a single operation, an operating signal for concurrently operating the hydraulic actuator and the electric actuator; and

a controller for switching between a combined drive mode and a hydraulic-alone drive mode, the combined drive mode being a mode to drive the two or more actuators to thereby drive the drive object when the operating device is operated, the hydraulic-alone drive mode being a mode to only the hydraulic actuator among the two or more actuators to thereby drive the drive object when the operating device is operated; and

an input device used by an operator to select any one of the plurality of drive modes including the combined drive mode and the hydraulic-alone drive mode;

wherein if the hydraulic-alone drive mode or the electric-alone drive mode is selected with the input device, the controller switches the drive mode of the drive object in accordance with the drive mode thus selected.