• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.1
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• pp.85-89
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• 2012

This study has been conducted to compare two cargo handling systems on MR tanker and Panamax tanker. Submerged hydraulic cargo pumps with hydraulic power packs and frequency converter controlled electric deepwell pumps will be investigated and compared on all aspects of initial cost, installation, operation and maintenance. The result of investigation shows Electric Systems have less manufacturing costs, higher environmental friendliness and reliable operation compare to Hydraulic Systems. Furthermore, the present experimental data will provide important database for Electric Systems onboard new ships and practical and empirical guidelines are constructed for further determine the design of the Electric Systems.

• Journal of Drive and Control
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• v.1 no.3
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• pp.47-56
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• 2004

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.201-211
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• 2002

In this research, we are trying to research about hydraulic system design and vehicle dynamic modeling far the development of the tire roller. The reason why we would like develop it is that tire roller is one of the most useful machine for the road construction site and application other construction equipments. Here, we conceptualize the new hydraulic system and derive the equations of motion fur dynamic analysis and also investigate system modeling by using a DAQ board. We design the hydraulic circuit of steering and traction mechanism system. This design can be used to create virtual prototypes of construction equipment. So, we studied tire roller to integrate development technology. In system analysis, we formulate hydraulic traction system model and hydraulic steering system model. Also, we integrate DAQ system to acquire experimental results in real tire roller equipment.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.05a
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• pp.157-160
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• 2004

In this paper, a performance characteristic pump and motor is investigated. The hydraulic pump and motor are axial piston type with swash plate. Proportional control valve which can control that plate is an important component for its performance characteristics. We will show the control characteristics for them Experiment results show that behavior can be shown with changing the various parameters.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.4
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• pp.432-439
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• 2003

In this research, we are trying to develop the new hydraulic driven tire roller which is conventionally operated by mechanical transmission system. The reason why we would like to develop it is that tire roller is one of the most useful machine for the road construction site and also imported totally from overseas. In this paper, we conceptualize the new hydraulic system and derive the equations of motion for dynamic analysis. And we investigate system modeling by using DAQ system. Finally, we will design the controller, which can manage the hydraulic circuit of steering and traction mechanism system. The advent of modern high-speed computers coupled with the application of high-fidelity simulation technology can be used to create “virtual prototypes of construction equipment. Tests conducted on these virtual prototypes may be used to augment actual machine testing, thereby lowering costs and shortening time to production. So, we studied tire roller to integrate development technology. In System Analysis, We formulate hydraulic driving system model and hydraulic steering system model. Also, We integrate DAQ system to acquire experimental result in real tire roller equipment.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.03a
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• pp.235-239
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• 2002

In this study, a AGV(Auto Guide Vehicle) is presented and the dynamic characteristics of AGV driving device is investigated. The design factors of hydraulic pump and motor is an important component for it's performance characteristics. the dynamic characteristics of hydraulic pump and motor is simulated by using commercial code AMESim. Simulation results show that each behavior can be predicted with changing the various parameters.

• Transactions of The Korea Fluid Power Systems Society
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• v.2 no.1
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• pp.1-8
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• 2005

Recently, swash plate type hydraulic axial piston motors/pumps are being extensively used in the world, because of simple design, light weight and effective cost. Structural problem of the swash plate type motor/pump is that tilting angle of swash plate should be limited to relatively small value and lateral farce on pistons has an undesirable effect in reciprocating motion. To solve these problems, piston rod mechanism, which is commonly used in bent axis type motor/pump, is considered to be applied to the swash plate type motor/pump. In this paper, kinematic analysis was done on the piston rod mechanism. A series of formula were derived and numerical calculations were done for a set of motor parameters.

• Journal of Drive and Control
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• v.10 no.2
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• pp.13-22
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• 2013

It is difficult to analytically derive a volumetric displacement formula of gerotor hydraulic pump/motor because geometric shape of rotors is complicated. An analytical method about the volumetric displacement is proposed in this work, which is relatively easy and based upon two physical concepts. The first one is energy conservation between hydraulic energy of the pump/motor and mechanical input/output energy. The second concept is torque equilibrium with respect to inner and outer rotors. The formula about the volumetric displacement is derived for the common case of inner and outer rotors rotate with respect to fixed axes. The formula is verified by comparing another analytical displacement formula, and it is numerically verified by comparing numerical results, which is calculated for geometric specification of a motor. The numerical displacement is calculated through CAD software program and MATLAB program. The proposed analytical formula can be utilized in analysis and design of hydraulic gerotor motors.

• Tribology and Lubricants
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• v.35 no.4
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• pp.215-221
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• 2019

A gerotor set consists of two elements, an inner rotor and an outer rotor. The outer rotor has one more tooth than the inner rotor and has its centerline positioned at a fixed eccentricity from the centerline of the inner rotor. Although gerotors come in a variety of geometric configurations, all gerotor sets share the basic principle of having generated tooth profiles that provide continuous tight sealing during operation. The size of the gerotor is proportional to the number of teeth and the amount of eccentricity. The interior of an inner rotor with a large number of teeth has an enough space to include other machine elements. In this paper, the double gerotor mechanism, constructed by putting a small gerotor in the interior of a large inner rotor, is conceptualized. The double gerotor set is composed of an inner rotor, a planetary rotor, and an outer rotor. The inside profile of the planetary rotor corresponds to the outer rotor profile of the small gerotor, and the outside profile is the inner rotor profile of the large gerotor. In the double gerotor, the centers of the inner and the outer rotor are coincident because the eccentricities of two gerotors are balanced. The operation of a double gerotor is examined by analyzing the planetary motion, and a feasibility study for application of the double gerotor for hydraulic motors and pumps is performed. The double gerotor set has much application potential as a component of hydraulic systems.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.154-164
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• 2011

This study was conducted to develop the semi-crawler type mini-forwarder that can be operated comfortable small-scale logging operation in the steep terrain and also used at a variety of operations such as the civil work in erosion control and forest-road. Considering the minimum turning radius and the width of forest operation road, the total length, width and loading capacity of the semi-crawler type mini-forwarder is 5,750 mm, 1,900 mm and $2.5m^{3}$, respectively. The maximum engine power is 96ps at 3600 rpm. Selected hydraulic pumps are consists of two main pumps and two sub-main pumps. Main hydraulic pumps are utilized to running motor of the front wheel and rear crawler. Sub-main pumps are utilized to the actuation parts such as steering, crane, out-rigger and dump cylinder. The transmission was adapted as the HST (Hydro-Static Transmission) system. The driving parts are designed and manufactured as the front wheel type and the rear crawler type. The steering type was manufactured as the ackerman type. Driving control parts type was designed and manufactured as driver's seat type of normal cars. It is also attached on auxiliary equipments such as winch, log grapple and out-rigger. The traveling speed of the semi-crawler type mini-forwarder in forest road was 5.3 km/hr to 7.7 km/hr.