Working vehicle

• US 8,030,860 B2
• Filed: 05/24/2007
• Issued: 10/04/2011
• Est. Priority Date: 06/01/2006
• Status: Active Grant

• Current Assignee: Takeuchi Mfg. Co.Ltd
• Original Assignee: Takeuchi Mfg. Co.Ltd
• Inventors: Yoshioka, Masao
• Primary Examiner(s): COLON SANTANA, EDUARDO
• Application Number:
  US12/301,300
• Publication Number:
  US 20090173554A1
• Time in Patent Office: 1,594 Days
• Field of Search: 318/3, 318/139, 318/140, 318/432, 318/434, 318/798, 318/801, 180/65.24, 180/65.29, 180/312, 290/7, 290/4.R, 290/40.B, 290/40.C, 320/132, 320/134, 701/50
• US Class Current: 318/139
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/20 Energy regeneration from auxiliary equipment
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2250/24 by lever actuation
• CPC Class Codes: B60L 2250/26 by pedal actuation
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: E02F 3/325 Backhoes of the miniature type
• CPC Class Codes: E02F 9/207 of the type electric propulsion units, e.g. electric motors or generators
• CPC Class Codes: E02F 9/2091 Control of energy storage means for electrical energy, e.g. battery or capacitors energy recovery arrangements in hydraulic or pneumatic drives E02F9/2217
• CPC Class Codes: E02F 9/2246 Control of prime movers, e.g. depending on the hydraulic load of work tools
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• 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
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 10/92 : Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles

Abstract

A power shovel vehicle including a hydraulic pump that outputs hydraulic oil for operating a hydraulic actuator, an electric motor for driving the hydraulic pump, a main battery for supplying direct current electric power, an inverter for converting the direct current electric power into alternating current electric power and operating the electric motor, a second relay for making and breaking the connection between the main battery and the inverter, an operating device for operating the hydraulic actuator, a controller for controlling operation of the hydraulic actuator and inverter, and turning on and off the second relay, a first relay for making and breaking the connection between the main battery and the controller, a power source monitoring controller for monitoring conditions of the main battery and turning on and off the first relay, a hydraulic sensor for detecting the discharge pressure of the hydraulic pump, and an electric current sensor for measuring a load current flowing into the inverter.

Claims

1. A working vehicle operated by a hydraulic actuator, comprising:

a hydraulic pump that outputs hydraulic oil for operating the hydraulic actuator;

an electric motor that drives the hydraulic pump;

a main battery that supplies direct current electric power;

an inverter that operates the electric motor by converting the direct current electric power from the main battery into alternating current electric power and supplying the alternating current electric power to the electric motor;

an electric motor relay that makes and breaks the connection between the main battery and the inverter;

an operating device for operating the hydraulic actuator;

a controller which is operated by the direct current electric power from the main battery, and which controls the operation of the hydraulic actuator and the inverter in accordance with operation signals output from the operation device, and makes and breaks the connection between the main battery and the inverter in use of the electric motor relay;

a controller relay that makes and breaks the connection between the main battery and the controller;

a power source monitoring controller that monitors the state of the main battery, and that makes and breaks the connection between the main battery and the controller in use of the controller relay;

an oil pressure sensor for measuring the output oil pressure of the hydraulic oil output from the hydraulic pump; and

a current sensor for measuring the value of the load current flowing from the main battery to the inverter wherein configuration is employed to execute;

a first step in which the controller, when determination is made that there has been no variation in the magnitude of the output oil pressure measured by the oil pressure sensor and the load current measured by the current sensor within a set period of time, breaks the connection between the main battery and the inverter and stops the motor in use of the electric motor relay;

a second step in which the controller, when determination is made that the state where no operating signal has been output from the operating device has continued during a predetermined set period of time, transmits a command signal to the electrical power monitoring controller; and

a third step in which the power source monitoring controller, when the transmitted signal is received, breaks the connection between the main battery and the controller in use of the controller relay, and stops the controller.

2. The working vehicle according to claim 1, wherein

the controller has a motor start up switch, and

in the second step, the controller, when determination is made that the motor start up switch has been operated, connects the main battery and the inverter in use of the electric motor relay, and starts the electric motor in order to return to the first step.

3. The working vehicle according to claim 1 or claim 2, wherein

the power source monitoring controller has a power supply switch, and

in the third step, after stopping the controller, the power source monitoring controller, when determination is made that the power supply switch has been operated, connects the main battery to the controller and the inverter using the controller relay and the electric motor relay in that order.