Automatic greasing system for construction machines and abnormality detecting method therefor

An automatic greasing system for a machine having a plurality of greased parts, said system comprising:

• a grease pump;
• a plurality of pipes for supplying grease from said grease pump to said plurality of greased parts of the machine;
• a drive source for driving said grease pump;
• a greasing operation completion detector for establishing a completion signal upon the completion of an operation of supplying grease from said grease pump to said plurality of greased parts;
• an abnormality detection circuit and an abnormality warning element, said abnormality detection circuit being adapted to establish a condition signal representing the condition of the automatic greasing system and to input said condition signal to said abnormality warning element, said condition signal being a high level signal when the automatic greasing system is normal and being a low level signal when the automatic greasing system is abnormal;
• and
• a controller for controlling said drive source, wherein said controller comprises:
• (a) an operating time accumulator for accumulating the operating times of said greased parts of the machine,
• (b) a first comparator for comparing a signal, which is responsive to the thus accumulated operating time, with a first predetermined value and for providing a comparison signal in response to results of the comparison, and
• (c) a drive signal generator for generating a drive signal generating command in response to the comparison signal, for outputting the drive signal generating command to said drive source to drive said grease pump when said accumulated operating time exceeds said first predetermined value, and for applying a drive signal stop command to said drive source to stop said grease pump in response to said completion signal.

An automatic greasing system for a machine having a plurality of greased parts, said system comprising:

• a grease pump;
• a plurality of pipes for supplying grease from said grease pump to said plurality of greased parts of the machine;
• a drive source for driving said grease pump;
• a drive operation detector for detecting that at least one of said plurality of greased parts is being driven for operation, and for establishing a drive detection signal in response thereto;
• a greasing operation completion detector installed on one of said plurality of pipes for establishing a completion signal representative of a completion of an operation of supplying grease from said grease pump to said plurality of greased parts of the machine;
• a controller for outputting start and stop command signals to said drive source for driving said grease pump;
• wherein said controller is adapted to accumulate drive operation time by inputting said drive detection signal of said drive operation detector;
• wherein said controller is adapted to output an operation command signal to the drive source for driving said grease pump, to automatically start passing grease from said grease pump to said plurality of greased parts, when the thus accumulated value of said drive operation time reaches a first preset value;
• and
• wherein said controller is adapted to automatically stop the passing of grease from the grease pump to said plurality of greased parts, by terminating the outputting of said operation command signal to the drive source for driving said grease pump;
• thereby repeatedly controlling the starting and the stopping of the grease pump.