Emergency control method for work device in construction equipment

• US 20050279088A1
• Filed: 07/14/2004
• Published: 12/22/2005
• Est. Priority Date: 03/10/2004
• Status: Abandoned Application

• Current Assignee: Volvo Construction Equipment Holding Sweden AB
• Original Assignee: Volvo Construction Equipment Holding Sweden AB
• Inventors: Kim, Dong Soo
• Application Number:
  US10/890,738
• Publication Number:
  US 20050279088A1
• Time in Patent Office: Days
• US Class Current: 60/449
• CPC Class Codes: E02F 9/2062 Control of propulsion units for control of the prime mover depending on the load in a hydraulic or pneumatic drive E02F9/2246
• CPC Class Codes: E02F 9/2228 including an electronic controller
• CPC Class Codes: E02F 9/226 Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
• CPC Class Codes: E02F 9/24 Safety devices , e.g. for preventing overload E02F9/226 takes precedence
• CPC Class Codes: E02F 9/267 Diagnosing or detecting failure of vehicles

Abstract

In the case an unexpected problem occurs in a power supply source like an engine during construction work using heavy equipment like an excavator, a emergency control method for work device of construction equipment of the present invention can be advantageously used for preventing a fall of the work device and ensuring a safe landing of the work device by driving a direction switching valve using the hydraulic pressure accumulated in an accumulator or an electric force. The control method preferably includes the steps of: determining a state of the engine; if the engine is in off state despite the absence of an engine off request signal, determining that the engine is stopped abnormally; and if the engine is stopped abnormally, outputting a control signal to the valve driving units in correspondence to the control input of the operation lever.

Claims

1. A emergency control method for work device of construction equipment mounted with an engine;

a hydraulic pump connected to the engine;

an actuator connected to the hydraulic pump;

a direction switching valve installed in a hydraulic path between the hydraulic pump and the actuator, and for controlling start-up or stoppage, and direction change of the actuator;

an operation lever driven by a driver and for generating a driving signal of the work device;

a controller for receiving an operational signal of the operation lever and operating control input of the operation lever, and outputting a control signal to switch the direction switching valve; and

valve driving units for driving the direction switching valve, according to the control signal outputted from the controller, the control method comprising the steps of;

determining whether the RPM of the engine is lower than a predetermined RPM, thereby determining a state of the engine;

if the engine is in off state despite the absence of an engine off request signal, determining that the engine is stopped abnormally; and

if the engine is stopped abnormally, outputting a control signal to the valve driving units in correspondence to the control input of the operation lever.

2. The control method according to claim 1, wherein if the engine is stopped abnormally, informing to the driver about the abnormal stoppage of the engine through a dashboard or an alarm.