ISO 12781-1:2011 幾何学的製品仕様（GPS）—平坦度—パート1：用語, 語彙と平坦度のパラメーター | ページ 6

3.1.1

平坦度

平面の性質

3.1.2

呼び平面

設計で指定された数学的に定義された平面

3.2.1

extracted surface

digital representation of the real surface

3.2.2

flatness surface

extracted surface (type plane) intentionally modified by a filter

Note 1 to entry: This is the surface to which the concepts and parameters of this part of ISO 12781 can be applied.

Note 2 to entry: The areal Gaussian filter is a convolution of two orthogonal profile Gaussian filters.

3.2.3

local flatness deviation

deviation of a point on a flatness surface from a reference plane, the deviation being normal to the reference plane

Note 1 to entry: The deviation is negative if from the reference plane the point lies in the direction of the material.

3.3.1

reference plane

associated plane fitting the flatness surface in accordance with specified conventions, to which the deviations from flatness and the flatness parameters are referred

3.3.1.1

minimum zone reference planes

two parallel planes enclosing the flatness surface and having the least separation

Note 1 to entry: The abbreviated term MZ is used to refer to minimum zone reference elements.

3.3.1.1.1

outer minimum zone reference plane

minimum zone reference plane outside the material

3.3.1.1.2

inner minimum zone reference plane

minimum zone reference plane inside the material

3.3.1.1.3

mean minimum zone reference plane

arithmetic mean plane of the minimum zone reference planes

3.3.1.2

least squares reference plane

plane such that the sum of the squares of the local flatness deviations is a minimum

3.4.1

peak-to-valley flatness deviation

value of the largest positive local flatness deviation added to the absolute value of the largest negative local flatness deviation

Note 1 to entry: The peak-to-valley flatness deviation is defined for all reference planes.

Note 2 to entry: The peak-to-valley straightness deviation is the only parameter that is defined for minimum zone reference planes.

Note 3 to entry: The modifier GT is used in specifications to indicate that a form tolerance applies to the peak-to-valley deviation relative to the least squares reference element.

3.4.2

peak-to-reference flatness deviation

value of the largest positive local flatness deviation from the least squares reference plane

Note 1 to entry: The peak-to-reference flatness deviation is only defined for least squares reference planes.

Note 2 to entry: The modifier GP is used in specifications to indicate that a form tolerance applies to the peak-to-reference deviation relative to the least squares reference element.

3.4.3

reference-to-valley flatness deviation

absolute value of the largest negative local flatness deviation from the least squares reference plane

Note 1 to entry: The reference-to-valley flatness deviation is only defined for least squares reference planes.

Note 2 to entry: The modifier GV is used in specifications to indicate that a form tolerance applies to the reference-to-valley deviation relative to the least squares reference element.

3.4.4

root-mean-square flatness deviation

∆ F_rms

square root of the sum of the squares of the local flatness deviations from the least squares reference plane

Note 1 to entry: The root-mean-square flatness deviation is only defined for least squares reference planes.

Note 2 to entry: The modifier GQ is used in specifications to indicate that a form tolerance applies to the root-mean-square deviation relative to the least squares reference element.