Battery-driven working machine

• US 5,991,677 A
• Filed: 06/04/1997
• Issued: 11/23/1999
• Est. Priority Date: 06/13/1996
• Status: Expired due to Term

• Current Assignee: Klaus Schmidt
• Original Assignee: Klaus Schmidt
• Inventors: Kinugawa, Hideki, Komiyama, Masayuki
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Hernandez, Olga
• Application Number:
  US08/869,138
• Time in Patent Office: 902 Days
• Field of Search: 701/50, 180/6.2, 37/348
• US Class Current: 701/50
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: E02F 9/207 of the type electric propulsion units, e.g. electric motors or generators
• CPC Class Codes: E02F 9/2285 Pilot-operated systems
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm

Abstract

There are provided with an electric motor driven by a battery, a hydraulic pump driven by the electric motor, a proximal actuator for actuating a working member by working oil from the hydraulic pump, a hydraulic motor for moving a working machine body, and an operating lever which can be operated between a neutral position and an operating position. There are provided with a control valve capable of cutting off a supply of working oil to the proximal actuator in a state where operating lever is positioned at an operating position, and a battery capacity sensor for detecting the capacity of the battery. There is provided a controller for outputting a control signal for cutting off a supply of working oil to the proximal actuator to the switching control valve in a state where the battery capacity value detected by the battery capacity sensor is at a level lower than a preset battery capacity reference value. It is possible to positively prevent the machine from being immoved at the working site.

Claims

1. A battery-driven working machine comprising:

a working machine body;

a battery mounted on said working machine body;

an electric motor mounted on said working machine body and driven by electric power from said battery;

a hydraulic pump mounted on said working machine body and operated by said electric motor;

an actuator operated by working oil discharged from said hydraulic pump to operate a working member provided on said working machine body;

a working machine moving means for moving said working machine body by electric power from said battery;

an operating lever which is operable between a neutral position for stopping said working member and an operating position at which said working member is operated and when said operating lever is positioned at the operating position, working oil is supplied to said actuator;

a battery capacity detection means for detecting the capacity of said battery; and

an actuator operation limiting means for limiting an operation of said actuator and said working machine moving means by reducing the power supplied to said electric motor from a continuous application of power to a series of pulses when said operating lever is operated, in a case where a battery capacity value detected by said battery capacity detection means is at a level lower than a preset value and above a preset, lower limit value.

2. The battery-driven working machine according to claim 1,

wherein said actuator operation limiting means causes a operating speed reduction of said actuator.

3. The battery-driven working machine according to claim 1,

wherein said actuator operation limiting means causes a reduction in power consumed by said actuator.

4. The battery-driven working machine according to claim 1,

wherein said actuator operation limiting means causes operation of said actuator to stop when a detected battery capacity is below said preset, lower limit value.

5. The battery-driven working machine according to claim 1, wherein the working machine is a hydraulic excavator.

6. The battery-driven working machine according to claim 5, wherein said actuator is a hydraulic cylinder for rotating an arm.

7. The battery-driven working machine according to claim 6,

wherein when the battery capacity value detected by said battery capacity detection means is at a level lower than said preset, lower limit value, said actuator operation limiting means causes operation of said hydraulic cylinder to stop.

8. The battery-driven working machine according to claim 1,

wherein said battery capacity detection means detects a specific gravity of battery liquid.

9. The battery-driven working machine according to claim 1,

wherein said battery capacity detection means is a voltmeter.

10. A battery-driven working machine comprising:

a working machine body;

a battery mounted on said working machine body;

an electric motor mounted on said working machine body and driven by electric power from said battery;

a hydraulic pump mounted on said working machine body and operated by said electric motor;

an actuator operated by working oil discharged from said hydraulic pump to operate a working member provided on said working machine body;

a moving mechanism adapted to move said working machine body by electric power from said battery;

an operating lever which is operable between a neutral position for stopping said working member and an operating position at which said working member is operated and when said operating lever is positioned at the operating position, working oil is supplied to said actuator;

a battery capacity detector adapted to detect the capacity of said battery; and

a voltage control mechanism adapted to limit an operation of said actuator and said working machine moving mechanism by reducing said electric power supplied to said electric motor from a continuous application of power to a series of power pulses when said operating lever is operated, in a case where a battery capacity value detected by said battery capacity detection means is at a level lower than a preset value and above a preset, lower limit value.

11. The battery-driven working machine according to claim 10,

wherein said voltage control mechanism causes a operating speed reduction of said actuator.

12. The battery-driven working machine according to claim 10,

wherein said voltage control mechanism causes a reduction in power consumed by said actuator.

13. The battery-driven working machine according to claim 10,

wherein said voltage control mechanism causes operation of said actuator to stop when a detected battery capacity is below said preset, lower limit value.

14. The battery-driven working machine according to claim 10,

wherein when the battery capacity value detected by said battery capacity detector is smaller than said preset value and above said preset, lower limit value, said voltage control mechanism causes an operating speed reduction of said actuator, and when the battery capacity value detected by said battery capacity detection means is smaller than said preset, lower limit value, said voltage control mechanism causes operation of said actuator to stop.

15. The battery-driven working machine according to claim 10,

wherein the working machine is a hydraulic excavator.

16. The battery-driven working machine according to claim 15,

wherein said actuator is a hydraulic cylinder for rotating an arm.

17. The battery-driven working machine according to claim 15,

wherein when the battery capacity value detected by said battery capacity detection means is at a level lower than said preset, lower limit value, said actuator operation limiting means causes operation of said hydraulic cylinder to stop.

18. The battery-driven working machine according to claim 10,

wherein said battery capacity detection means detects a specific gravity of battery liquid.

19. The battery-driven working machine according to claim 10,

wherein said battery capacity detection means is a voltmeter.

20. A battery-driven working machine comprising:

a working machine body;

a battery mounted on said working machine body;

an electric motor mounted on said working machine body and driven by electric power from said battery;

a hydraulic pump mounted on said working machine body and operated by said electric motor;

an actuator operated by working oil discharged from said hydraulic pump to operate a working member provided on said working machine body;

a working machine moving means for moving said working machine body by said battery;

an operating lever which is operable between a neutral position for stopping said working member and an operating position at which said working member is operated and when said operating lever is positioned at the operating position, working oil is supplied to said actuator;

a battery capacity detection means for detecting the capacity of said battery;

an actuator operation limiting means for limiting an operation of said actuator and said working machine moving means when said operating lever is operated, in a case where a battery capacity value detected by said battery capacity detection means is at a level lower than a preset value and above a preset, lower limit value; and

wherein when the battery capacity value detected by said battery capacity detection means is smaller than said preset value and above said preset, lower limit value, said actuator operation limiting means causes an operating speed reduction of said actuator, and when the battery capacity value detected by said battery capacity detection means is smaller than said preset, lower limit value, said actuator operation limiting means causes operation of said actuator to stop.