Introduction and Working Principle of Excavator Hydraulic Breaker

Introduction of excavator hydraulic breaker

The excavator hydraulic breaker is referred to as “breaker” or “crusher”. The power source of the excavtor hydraulic breaker is the pressure provided by the excavator. It can crush stones and rocks more effectively during construction and improve work efficiency. The hydraulic breaker is selected according to the model of the excavator and the environment in which the work is performed. The structure of the excavator hydraulic breaker is mainly divided into three blocks: the upper cylinder (nitrogen chamber), the middle cylinder (cylinder), and the lower cylinder. The three are connected by four through-body bolts. The upper cylinder is used to store low-pressure nitrogen. The middle cylinder is a piston, an accumulator, an oil seal, a gas exchange valve, etc., and the lower cylinder has steel brazing, flat pins, horizontal pins, inner and outer bushings, and the like.

Working principle of excavator hydraulic breaker

Excavator hydraulic breaker detailed working principle first,
Return acceleration phase: At the beginning of the piston return stroke, the last impact of the piston has ended and is in a momentary pause state. At this time, the main valve V2 chamber is a low pressure chamber, and the V4 chamber is a constant high pressure chamber, so the main spool is at the lower limit position. In this way, the front chamber V1 of the piston communicates with the high-pressure oil through the main valve core, and the rear chamber V3 of the piston is always in communication with the oil return chamber, which is a low pressure. Therefore, the piston accelerates in the return stroke under the action of the high pressure oil in the front chamber, and simultaneously compresses the tail nitrogen. The chamber is nitrogened for adiabatic compression.

Excavator hydraulic breaker detailed working principle Second,
The return brake movement: the piston continues to move back to the action under the action of high pressure oil. When the lower side of the middle section of the piston crosses the lower side of the control port, the high pressure oil in the V1 chamber enters the main valve. In the V2 chamber, the hydraulic pressure acting on the main spool through the V2 chamber is greater than the hydraulic pressure acting on the main spool at the V4 chamber, thereby forcing the spool to start the reversing motion. The movement of the spool gradually reduces the high-pressure oil entering the V1 cavity, so that the return stroke force corresponding to the piston is gradually reduced, and the return resistance applied by the compressed nitrogen is getting larger and larger, and the piston is transferred to the return stroke. Braking phase. The spool will eventually shut off the pressure oil in the V1 chamber and the piston will quickly stop the return stroke.

Excavator hydraulic breaker detailed working principle Third,
Stroke acceleration movement: When the piston stops the return movement, it will immediately turn into the stroke movement phase. At this time, the main spool has opened the oil passage of the front chamber V1 of the piston to the oil return chamber of the main spool, so that the oil in the front chamber of the piston can be smoothly discharged. At this point, the piston begins a rapid stroke motion under the adiabatic expansion force of nitrogen. When the piston is in stroke motion, the spool will reliably stay in the upper limit position.

Excavator hydraulic breaker detailed working principle Fourth,
The special state: the piston hits the pause state Under the nitrogen chamber adiabatic expansion of the nitrogen chamber, the piston is quasi-accelerated (the banquet acceleration is gradually reduced). When the upper side of the middle section of the piston passes over the upper side of the control port, the V2 cavity of the main spool communicates with the return oil, and the V2 cavity becomes a low pressure chamber. The spool will begin to reverse the downward movement under the action of the high pressure oil in the V4 chamber. At this point, the piston with sufficient energy has been struck against the drill rod to complete the impact action. The spool continues to move downwards, and when the spool moves to the lower limit position, the piston is in an instantaneous pause phase. At this point, the piston ends a working cycle. Subsequently, the piston rebounded after the impact and began the next work cycle.