• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.5
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• pp.148-155
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• 2001

Hydraulic breaker is currently used for many civil engineering areas owing to the ease of changing the tooling mechanism. However, due to a high noise level, it has been one of notorious sources of environmental noise and the prevailing environmental concerns force the manufacturers to reduce the radiated noise levee during operations. To comply with such concerns, the present study is focused on designing and developing a low-noise hydraulic breaker For this purpose, sound sources are identified and relative contributions are rated. Acoustic enclosure. sealing systems, and low-nolle type chisel have been developed and applied to the actual machine. As a result, the radiated noise from the developed low-noose hydraulic breaker is reduced more than 13 dB(A) In comparison with the conventional hydraulic bleaker.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.683-686
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• 2007

The characteristics of radiated noise from the hydraulic breaker were measured under the revised regulation of Ministry of environment. The directivity of radiated noise was also measured at a distance of 7.5 m and a height of 1.5 m from the operating hydraulic breaker.

• Transactions of The Korea Fluid Power Systems Society
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• v.7 no.1
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• pp.11-19
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• 2010

A gas-assisted hydraulic breaker uses both hydraulic and pneumatic energies and the appropriate balance between them mostly effects its performance. Mathematical modeling of the breaker is established and verified by experiment. Through sensitivity analysis using AMESim, the key design parameters are selected, which mostly affect the performance of the breaker. Taguchi method is used to optimize the key design parameters to maximize the output power for long and short strokes through simulation. As the result, the output power as well as the impact energy are increased significantly compared with the existing design. The pressure pulsation in the supply line is reduced to a tolerable level and the dynamic characteristics of the piston displacement is also improved by the optimization.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.2
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• pp.138-143
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• 2010

Hydraulic breakers are widely used for mining and construction engineering area but make serious noise problem. The noise is generated between a chisel and a piston when they are hit by a fluid power. This study proposed noise reduction method by the change of a chisel in a hydraulic breaker. In the new design, a different material is inserted inside of a chisel. The proposed design is analyzed and simulated by the use of a numerical method. A chisel by the new design was installed in a hydraulic breaker and experimented for sound pressure level. As a result, the noise of hydraulic breaker can be reduced more than 4 dB by simply changing a chisel.

• Transactions of The Korea Fluid Power Systems Society
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• v.6 no.1
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• pp.17-24
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• 2009

The performance improvement of a small-size integrated-type fully hydraulic breaker is studied in this paper. Mathematical modeling of the breaker is established and verified by experiment. Through sensitivity analysis using AMESim, the key design parameters are selected and nearly optimized to maximize the impact energy as well as to improve the dynamic characteristics such as the piston upper chamber pressure, piston and valve displacements. As a result, the impact energy, blows per minute(bpm) and output power are increased by 52.9%, 1%, and 55.6%, respectively compared with the current design. The dynamic characteristics of the piston upper chamber pressure, piston and valve displacements are also improved by the design change.

• Transactions of The Korea Fluid Power Systems Society
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• v.5 no.3
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• pp.1-8
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• 2008

The optimal design of a large-size fully hydraulic breaker is studied in this paper. Mathematical modeling of the breaker is established and verified by experiments. Through sensitivity analysis, the key design parameters of the breaker are selected, which mostly affect the performance of the breaker. Taguchi method is used to optimize the key design parameters in order to maximize the output power through simulation using AMESim. As a result, the impact energy is increased by 18.9% and the output power is increased by 12.4% compared with the current design. The pressure pulsation in the supply line is also reduced by the optimization.

• Journal of Drive and Control
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• v.19 no.3
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• pp.1-8
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• 2022

In this paper, the design of automatic impact force control mechanism of hydraulic breaker was studied. The control mechanism uses the change of piston upper chamber pressure, when the hydraulic breaker impacts various strength rock. The piston stroke is controlled by rock strength sensing valve, piston stroke switching valve, and piston control valve. It is imperative to denote the area of each valve section, the spring constant of the spring. It provides convenience to users by automatically adjusting the appropriate striking force, according to the strength of the rock. Additionally, by increasing work productivity, it can contribute to reducing greenhouse gas emissions due to fuel efficiency reduction.

• Journal of Drive and Control
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• v.18 no.4
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• pp.65-71
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• 2021

In this paper, the development of a vibration reduction device for hydraulic breakers was studied. Generally, a hydraulic breaker generates shock vibrations while working. When using vibration-proof rubber, shock vibrations are reduced, but without this, shock vibrations are repeatedly generated. Such repeated shock vibrations not only lower the fatigue strength of hydraulic breakers and excavators equipped with them but also increase the fatigue of the workers. This paper proposes the possibility of reducing shock vibration by using a dynamic vibration absorber.

• Journal of Drive and Control
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• v.8 no.2
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• pp.49-53
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• 2011

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.189-190
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• 2009