A new method for analysing and calculating angles on cutting tools

The CNC machining has been one of the most recurrent processes used for finishing NNS components. This paper presents a new method for the generation of tool paths for machining 3D NNS models. The proposed approach comprises two machining stages: rough cut and finish cut, and three types of cutting tools: ball-end mill, flat-end mill and fillet-end mill. The proposed tool path generation algorithm is based on: (1) approximation of the model surfaces by points using slice planes and visibility analysis, (2) accessibility analysis of the tool, (3) approximation error and tolerance evaluation, (4) collision analysis of tool and tool holder. The tools paths generated are exported as a CNC program. The implementation was carried out in C++ using the ACIS® geometric modeling kernel to support the required geometric operations. To prove the effectiveness of the system several models with variable geometric complexity were tested. The results have shown that the proposed system is effective and therefore can be used to generate the tool paths required for finishing 3D NNS components.

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A New Method for Modeling of Cutting Tools Associated With Rolling Axodes

Volume 4: 3rd Design for Manufacturing Conference ◽

10.1115/detc98/dfm-5714 ◽

1998 ◽

Author(s):

Nicolae Oancea ◽

Victor G. Oancea

Keyword(s):

Cutting Tools ◽

New Method ◽

Contact Points ◽

Alternative Method ◽

Solution Of Equations ◽

Tool Profile ◽

Family Of Curves ◽

Envelope Theory

Abstract Most of the existing methods for determining the profiles of cutting tools that work by wrapping are based on the envelope theory which requires cumbersome analytical formulations associated with the solution of equations not always easy to resolve. This work presents a new alternative method for studying conjugated surfaces associated with rolling axodes. The original meshing surfaces are replaced by a family of curves of substitution which gives a simpler interpretation of the envelope theory. The meshing line and the contact points can be easily determined. An equidistant to the tool profile can be simply calculated which can be very useful in the case of machining with cylindrical abrasive disks. Several examples are shown for rack, shaper and rotational cutters.

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Geometrical Modeling of Surface Generation Through Wrapping

Journal of Manufacturing Science and Engineering ◽

10.1115/1.2836831 ◽

1997 ◽

Vol 119 (4B) ◽

pp. 829-834 ◽

Cited By ~ 2

Author(s):

N. Oancea ◽

V. G. Oancea

Keyword(s):

Inverse Problem ◽

Numerical Method ◽

Cutting Tools ◽

Analytical Form ◽

New Method ◽

Surface Generation ◽

Minimal Distance ◽

Geometrical Modeling ◽

Tool Profile ◽

Envelope Theory

A number of methods exist for determining profiles of cutting tools that work by wrapping. Most of these methods are based on the envelope theory and almost inevitably require cumbersome analytical formulations not always easy to resolve. This work presents a new method for studying conjugated surfaces associated with rolling axodes. Originally devised in an analytical form in a previous work of the first author, a purely numerical method is developed here based on a theorem which we call “the theorem of the minimal distance.” The advantage is twofold: first, geometrical modeling of tool profile calculation is possible even for profiles which cannot be described analytically; second, a very useful tool is provided for the inverse problem—starting from the measured cutting edges profiles, one can calculate the effectively generated surface on the workpiece. Several examples are shown for rack, shaper, and rotational cutters.

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A New Method for Cutting Tools Design

Volume 3: 5th Design for Manufacturing Conference ◽

10.1115/detc2000/dfm-14005 ◽

2000 ◽

Author(s):

Nicolae Oancea ◽

Victor G. Oancea ◽

Epureanu Alexandru

Keyword(s):

Cutting Tools ◽

New Method ◽

Discrete Representation ◽

Alternative Method ◽

Envelope Theory

Abstract Most of the existing methods for determining the profiles of cutting tools that work by wrapping are based on the envelope theory. This theory requires cumbersome analytical formulations resulting in sets of equations not always easy to solve. This work presents a new alternative method for studying conjugated surfaces associated with rolling axodes by using a discrete representation of the tool. The new method is based on studying the trajectories of points on the tool relative to the workpiece in order to define the tool’s profile. Several examples are shown for rack, shaper and rotational cutters.

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The new method for assessing rock abrasivity in terms of wear of conical picks

New Trends in Production Engineering ◽

10.2478/ntpe-2019-0019 ◽

2019 ◽

Vol 2 (1) ◽

pp. 186-194 ◽

Cited By ~ 1

Author(s):

Kamil Mucha

Keyword(s):

Abrasive Wear ◽

Mass Loss ◽

Rock Sample ◽

Raw Materials ◽

Cutting Tools ◽

Laboratory Method ◽

New Method ◽

Hard Coal ◽

Conical Picks ◽

Rock Abrasivity

Abstract During the exploitation of mineral raw materials, a cutting tool is an element that is directly in contact with the unmined stone being cut. The most commonly used cutting tools include conical picks. The increasing pressure to reduce mining costs causes an increasing demand for affordable and reliable ways to increase the reliability of mining machines. Abrasive wear is the most common process affecting the wear of shearer picks, hence a good and simple laboratory method for assessing rocks abrasivity is needed. The new method was developed in the aspect of selection of conical picks with appropriate protection of the pick working part, increasing its durability. The method involves the assessment of mass abrasive wear of a standard steel pin and rock sample, and the determination of the abrasivity index Wz of the tested rock, as the ratio of the mass loss of the steel pin to the mass loss of the rock sample. The article presents the procedure of conducting tests, construction of a laboratory test stand and the use of the developed method to assess the abrasivity of gangue rocks occurring in the currently cut tunnel excavations of Polish hard coal mines.

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Selective Sampling and Orientation of Non-Homogeneous Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100238 ◽

1968 ◽

Vol 26 ◽

pp. 98-99

Author(s):

C. C. Clawson ◽

L. W. Anderson ◽

R. A. Good

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Light Microscopy ◽

Random Sampling ◽

New Method ◽

Microscope Examination ◽

Small Areas ◽

Selective Sampling ◽

Large Numbers ◽

Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

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