Hybrid working machine

• US 7,728,449 B2
• Filed: 09/24/2007
• Issued: 06/01/2010
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Kobelco Construction Machinery Company Limited (Kobe Steel Limited)
• Original Assignee: Kobelco Construction Machinery Company Limited (Kobe Steel Limited)
• Inventors: Kagoshima, Masayuki, Komiyama, Masayuki
• Primary Examiner(s): Ponomarenko, Nicholas
• Application Number:
  US11/860,019
• Publication Number:
  US 20080093864A1
• Time in Patent Office: 981 Days
• Field of Search: 290/4.R, 290/4.D, 290/40.C, 290/40.B, 180/65.2, 180/65.4, 604/31
• US Class Current: 290/40.00C
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2250/24 by lever actuation
• CPC Class Codes: B60L 3/0023 Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 58/14 Preventing excessive discharging
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: E02F 9/2075 of the hybrid type for vehicles in general B60W20/00
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• 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
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

The present invention is to drive a hydraulic pump and a generator motor by an engine, electrically charge a battery by a generator operation of the generator motor, and assist the engine through driving the generator motor by electric power of the battery. On the premise of the configuration above, when a deviation between a target rotation speed of the engine and an actual rotation speed of the engine is equal to or more than a preset value, and when a residual amount of fuel is equal to or less than a preset value, it is considered to be engine failure or an operation state which is directly connected to the engine failure and an engine assisting action is automatically stopped.

Claims

1. A hybrid working machine, comprising:

a hydraulic pump for driving a hydraulic actuator;

a generator motor for performing a generator operation and a motor operation;

an engine for driving said hydraulic pump and said generator motor, the engine serving as a common power source therefor;

an electric storage device electrically charged by the generator operation of said generator motor, the electric storage device being configured such that said generator motor is driven by electric power of the electric storage device so as to perform the motor operation for assisting said engine;

controlling means for controlling an engine assisting action by said generator motor; and

operation state detecting means for detecting engine failure or an operation state which is directly connected to the engine failure, wherein

said controlling means is adapted to stop the engine assisting action when said operation state detecting means detects the engine failure or the operation state which is directly connected to the engine failure.

2. The hybrid working machine according to claim 1,

wherein an engine rotation speed detecting means for detecting an actual rotation speed of said engine serves as said operation state detecting means, and wherein

said controlling means determines a deviation between a target rotation speed of said engine and the actual rotation speed of said engine and stops the engine assisting action when the deviation is equal to or more than a value preset as the engine failure or a value which is directly connected to the engine failure.

3. The hybrid working machine according to claim 1,

wherein fuel detecting means for detecting a residual amount of fuel serves as said operation state detecting means, the fuel detecting means being configured to stop the engine assisting action when the residual amount of fuel is equal to or less than a value preset as the engine failure or a value which is directly connected to the engine failure.