• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.478-487
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• 1996

A " plucking rolls device" was developed in this study to improve the quality of harvested tea leaves. In this report, the outline of the system and the results of performance experiments in our laboratory are discussed. Tow kinds of performance experiments were carried out. The first experiment checked harvesting accuracy by using a plucking unit that was developed for harvesting machine installation. The second experiment was a harvesting experiment which utilized a fron bar in order to prevent cutting of the tea buds which had been a problem in precious experiments . As a results of the first experiments , it was confirmed that selective harvesting obtained high quality tea leaves. but a cutting problem that, when the harvesting seed was faster than the working speed, which was non-selective harvesting , was also seen. In the second experiment, the cutting rate decreased to a maximum of 50% level, when tea buds most bent ahead by the front bar. The effect was seen that cutt ng problem was alleviated from this.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.245-250
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• 2003

This research conducted milling tests to study effects of cutting environment conditions of ball end mills on the characteristics of hard milling process. KP4 steels and STD11 heat treated steels were used as the workpiece and WC-Co ball end mill tools with TiAIN coated were utilized in the cutting tests. Dry cutting without coolant and semi-dry cutting using botanical oil coolant were conducted and MQL (Minimum Quantity Lubricant) device was used to spray coolant. Cutting forces, tool wear and surface roughness were measured in the cutting tests. Results showed that dry cutting of KP4 and hardened STD11 specimens produced better surface quality and wear performance than MQL spray cutting did.

• Transactions of Materials Processing
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• v.13 no.1
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• pp.45-52
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• 2004

This research conducted milling tests to study effects of cutting environment conditions of ball end mills on the characteristics of hard milling process. KP4 steels and STD11 heat treated steels were used as the workpiece and WC-Co ball end mill tools with TiAlN coated were utilized in the cutting tests. Dry cutting without coolant and semi-dry cutting using botanical oil coolant were conducted and MQL(Minimum Quantity Lubricant) device was used to spray coolant. Cutting forces, tool wear and surface roughness were measured in the cutting tests. Results showed that dry cutting of KP4 and hardened STD11 specimens produced better surface quality and wear performance than MQL spray cutting did.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.238-244
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• 2004

This research conducted milling tests to study effects of cutting environment conditions of ball end milts on the characteristics of high speed milling cutting process. KP4 steels and STD11 heat treated steels were used as the workpiece and WC-Co ball end mill tools with TiAIN coated were utilized in the cutting tests. Dry cutting without coolant and semidry cutting using botanical oil coolant by the MQL(Minimum Quantity Lubricant) device were conducted. Cutting forces, tool wear and surface roughness were measured in the cutting tests. Results showed that MQL spray cutting of KP4 and hardened STD11 specimens produced better surface quality and wear performance than dry cutting did.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.3
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• pp.29-35
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• 2006

Various types of elliptical motions are generated by PZT mechanism which is composed of two parallel piezoelectric actuators. Elliptical vibration cutting(EVC) is obtained by attaching single crystal diamond cutting tool to the mechanism, and V-grooving for Brass and Aluminum is carried out by applying the EVC. It is experimentally observed that the cutting force in the process of the EVC reduces compared to the ordinary non-vibration cutting, which is due to the decrease of undeformed chip thickness and frictional force between the tool and chip. Ultrasonic elliptical vibration cutting(UEVC) suppresses burr formation and decreases cutting force still more, so UEVC makes it possible to enhance the shape accuracy of machined surface.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.4
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• pp.611-617
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• 1989

A jet cutting system is a new concept of cutting device wihch requires high pressure up to thousands of atmospheric pressure. The use of water as a cutting medium brings in many of working advantages such as no dust, no gas, and no thermal distortion. And an introduction of abrasives into the water jet flow increases signigicantly cutting abilities and improves cutting performance. Cutting with abrasive water jet involves many operating variables, including design of the cutting system. For efficient cutting, the operating parameters have to chosen properly. In spite of several attempts to develop the cutting model theoretically, all of the optimization of the operating parameters is based upon exerimental results of each jet cutting system. In this paper, the effect of the parameters was measured and analysed in terms of pressure, abrasive, and transverse rate of a workpiece. Most of all, sufficient feeding of abrasives is the most important factor for efficient cutting performance.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.72-77
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• 1999

This paper presents 2-dimensional vibration cutting increases dynamic stiffness of tool support and improves the quality of machined surface in micro-machining. 2-dimensional vibration cutting is generated by two piezo actuators arranged orthogonally. A sine-type voltage is input to one actuator and a phase-shifted sine-type voltage is input the other. Then the vibration device actuates the tool in a 2-D elliptical motion with pulsed cutting force. It is a characteristic of 2-D vibration cutting that some negative thrust force occurs as the direction of friction on a tool rake surface is reversed. It helps not only chip flow smoothly and continuously but also cutting force be reduced. The quality of machined surface by 2-D vibration cutting depends on such parameters as vibration amplitude, frequency, cutting speed, depth of cut, etc. Compared to conventional cutting through tool path simulation and experiments under several conditions, the 2-D vibration cutting is verified to bring forth a great decrease of cutting forces, much better surface roughness and moreover much less burr.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.386-393
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• 2018

Purpose: Chicken cutting is done manually, which is inefficient, unhygienic, and carries a high accident risk during processing. This study develops and evaluates an automatic chicken cutting machine that suits small-scale workplaces. Methods: This study developed an automatic chicken cutting machine equipped with four traverse blades and two longitudinal blades. An experiment was conducted with various blade rotating speeds and tray feed rates to evaluate the machine's performance. The chicken loss rate and chicken piece weights were measured to calculate the coefficient of variation (CV), thereby determining processing uniformity. Results: The optimal cutting conditions with the smallest chicken loss rate were 0.05 m/s tray feed speed and 18.8 m/s and 16.4 m/s for the traverse and longitudinal blades, respectively. The processing ran at 55.3 chickens per hour and the chicken pieces were more uniform when using the device than for hand-work processed pieces. Conclusions: The loss rate increased in proportion to the cutting-blade rotation speed due to the high cutting rate in meat. The loss rate also increased as the tray feed speed slowed because the cutting blade pushed the chicken meat. The tray feed speed should be increased to improve the amount processed per hour.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.37-38
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• 2011

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.9
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• pp.72-80
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• 2019

In this task, the tool dynamometer design and manufacture, and the Ansys S/W structural analysis program for tool attachment that satisfies the cutting force measurement requirements of the tool dynamometer system are used to determine the cutting force generated by metal cutting using 3-axis static structural analysis and the LabVIEW system. The cutting power in a cutting process using a milling tool for processing metals provides useful information for understanding the processing, optimization, tool status monitoring, and tool design. Thus, various methods of measuring cutting power have been proposed. The device consists of a strain-gauge-based sensor fitted to a new design force sensing element, which is then placed in a force reduction. The force-sensing element is designed as a symmetrical cross beam with four arms of a rectangular parallel line. Furthermore, data duplication is eliminated by the appropriate setting the strain gauge attachment position and the construction of a suitable Wheatstone full-bridge circuit. This device is intended for use with rotating spindles such as milling tools. Verification and machining tests were performed to determine the static and dynamic characteristics of the tool dynamometer. The verification tests were performed by analyzing the difference between strain data measured by weight and that derived by theoretical calculations. Processing test was performed by attaching a tool dynamometer to the MCT to analyze data generated by the measuring equipment during machining. To maintain high productivity and precision, the system monitors and suppresses process disturbances such as chatter vibration, imbalances, overload, collision, forced vibration due to tool failure, and excessive tool wear; additionally, a tool dynamometer with a high signal-to-noise ratio is provided.