Design of a contactless powered and piezoelectric-actuated tool for non-resonant low-frequency vibration-assisted machining of brittle-hard materials

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-021-07436-1 ◽

2021 ◽

Author(s):

Jens Brier ◽

Friedrich Bleicher

Keyword(s):

Low Frequency ◽

Maximum Amplitude ◽

System Configuration ◽

Hard Materials ◽

Low Frequency Vibration ◽

Ultrasonic Assisted ◽

Tool Shape ◽

Process Heating ◽

Working Frequency ◽

Actuator Design

AbstractUltrasonic-assisted grinding (UAG) is the state-of-the-art process for machining of brittle-hard materials. In comparison to conventional processes, the main advantages lie in the reduction of tool wear and process forces. Such a vibration system is based on a resonant actuator and a power supply unit generating the alternating current. Both units are interconnected by a contactless energy transfer (CET) system. This system configuration shows one optimal working point at the resonant frequency with maximum amplitude, which is significantly depending on the tool shape. In this work, a piezo-activated tool system is designed to realize non-resonant low-frequency vibrations. Major emphasis is put on the thermal behavior of the piezo drive, particularly on the in-process heating depending on the working frequency. In addition, focus lays on the theoretical and numerical design of the radial operating transducer CET system for a previously set actuator design. As a result, this system configuration offers a fully variable adjustment of the amplitude from under 1 to over 50 μm at frequency range. Outside this range, higher amplitudes can be achieved for short periods to the detriment of the fatigue strength according to FKM.

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Development of Fixing System for 2-Axis Micro Deep Drilling Assisted by Low Frequency Vibration

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.625.149 ◽

2014 ◽

Vol 625 ◽

pp. 149-154 ◽

Cited By ~ 1

Author(s):

Ivan Burdukovskyi ◽

Jun'ichi Kaneko ◽

Kenichiro Horio

Keyword(s):

Amplitude Ratio ◽

Low Frequency ◽

Two Dimensions ◽

Drilling Process ◽

Vibration Source ◽

Deep Drilling ◽

Machining Time ◽

Hard Materials ◽

Low Frequency Vibration ◽

Vertical Displacements

Micro deep drilling of hard materials is required to involve step feed in process that grows up machining time. To increase the step feed, a method with low frequency vibration (frequency ~190 Hz, amplitude ~10 μm) by oscillating of workpiece has been proposed. Previous study is focused on method of 1-axis drilling process assisted by low frequency vibration. Introducing the method with low frequency vibration to 2-axis drilling process on a curved surface is required to oscillate the workpiece in two dimensions. Purpose of our study is to design fixing system with the 2-dimansional low frequency vibration. Vibration source is needed to change for providing the 2-dimansional vibration. Fixing system for 2-dimensional vibration (FS2DV) consists of two vibration sources in horizontal and vertical directions with spring systems along it action. The 2-dimensional vibration is controlled by amplitude ratio of the vibrations from each source. As a result, we have succeeded low frequency vibration of the workpiece with assigned direction. The resulting vibration is verified (measuring of instantaneous horizontal and vertical displacements).

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Configuration Method of Fixing System with 2-Dimensionally Low-Frequency Vibration for Drilling to Decrease Influence from Unintended Displacement of Workpiece

International Journal of Automation Technology ◽

10.20965/ijat.2015.p0161 ◽

2015 ◽

Vol 9 (2) ◽

pp. 161-169

Author(s):

Ivan Burdukovskyi ◽

◽

Jun’ichi Kaneko ◽

Kenichiro Horio

Keyword(s):

Vibration Frequency ◽

Thrust Force ◽

Function Analysis ◽

Low Frequency ◽

Drilling Process ◽

Deep Drilling ◽

Machining Time ◽

Hard Materials ◽

Error Frequency ◽

Low Frequency Vibration

Micro deep drilling of hard materials requires introducing of step feed in process that increases machining time. To decrease the machining time by increasing the step feed, we apply low-frequency vibration (∼10 μm, 150 – 250 Hz) to the drilling process by oscillating the workpiece. To cope with the low-frequency vibration-assisted drilling of a curved surface, we have developed a fixing system for 2-dimensional vibration. The Fixing System for 2-Dimensional Vibration (FS2DV) consists of horizontal, and vertical actuators plus spring systems with variable rigidities along the directions of the actuators. A thrust force of 6 – 10 N from the drilling process may induce an unintended displacement of the workpiece. If the rigidities of the horizontal and the vertical spring systems are not balanced, unintended displacement may create diameter error during the drilling process. In this study, a method is proposed for configuring of the FS2DV with balanced spring systems to minimize the effects of the unintended displacement on diameter error. Frequency response function analysis of the vertical and horizontal spring systems is done for successful use of the FS2DV during the low-frequency vibration-assisted 2-axis drilling. Based on this analysis, setting requirements for the FS2DV are proposed for a particular vibration frequency. The behavior of the resultant vibration is evaluated while force is loaded along the intended angle of the drilling process. As a result, the effects of unintended displacement at the FS2DVare decreased for use within the vibration frequency range of 150 – 250 Hz with the vibration amplitude of 10 μm. The system can be used properly with a thrust force of up to 10 N and any angle from 0 to 90° by selecting appropriate rigidities for the spring systems.

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Lag Time and Working Frequency of FBG Strain Sensor

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.381-382.505 ◽

2008 ◽

Vol 381-382 ◽

pp. 505-508

Author(s):

Li Sun ◽

Hong Nan Li ◽

D.Z. Liang ◽

J. Fang

Keyword(s):

Low Frequency ◽

Strain Sensor ◽

Lag Time ◽

Strain Sensors ◽

Dynamic Strain ◽

Shake Table ◽

Vibration System ◽

Strain Wave ◽

Low Frequency Vibration ◽

Working Frequency

This paper investigates the lag time and the highest working frequency of Fiber Bragg Grating strain sensor in which strain wave transfers to bare FBG by analyzing the transmit course of the strain wave. The results show that the FBG strain sensor is applicable to the measurement of low frequency vibration in engineering. As its application, FBG strain sensors are used in the shake table test of offshore platform model and show good capability in measuring the dynamic strain of vibration system with low frequency.

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A Study on the Fine Structure of the Lateral Line Organ of the Sea Eel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073684 ◽

1973 ◽

Vol 31 ◽

pp. 648-649

Author(s):

K. Hama

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Lateral Line ◽

Low Frequency ◽

Sensory Cells ◽

Apical Surface ◽

Voltage Electron ◽

Sensory Epithelia ◽

Low Frequency Vibration ◽

Transmission Electron

The lateral line organs of the sea eel consist of canal and pit organs which are different in function. The former is a low frequency vibration detector whereas the latter functions as an ion receptor as well as a mechano receptor.The fine structure of the sensory epithelia of both organs were studied by means of ordinary transmission electron microscope, high voltage electron microscope and of surface scanning electron microscope.The sensory cells of the canal organ are polarized in front-caudal direction and those of the pit organ are polarized in dorso-ventral direction. The sensory epithelia of both organs have thinner surface coats compared to the surrounding ordinary epithelial cells, which have very thick fuzzy coatings on the apical surface.

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