ISO 10303-47:1997 download.Industrial automation systems and Integration — Product data representation and exchange — Part 47: Integrated generic resource: Shape variation tolerances.
Iso 10303 is an lniernaional Standard for the compuier-interpretablc representation and exchange of product data. The objective is to provide a neutral mechanism capahic of describing product data throughout the life cycle of a product, independent from any particular system. The naturc of this description makes it suitable not only for neutral file exchange, hut also as a basis for implementing and sharing product data bases and archiving.
ISO 10303-47 is organized as a series of pans, each published separately. The parts of ISO 10303 fall into onc of the following sales: description methods, integrated resources, application interpreted cofismicis, application proocok, abstract test suites, implementation methods, and contiirmance testing. The series axe described in ISO 10303-i. This part of ISO 10303 is a member of the integrated resources series. Major subdivisions of this part of ISO 10303 arc:
— shape aspect definition, provides resources for the representations of shapes to which dimensions and tolerances arc applied;
— shape dimension, provides resources for the representations of size and relative location to mcci the dimensioning requirements found in engineering design;
— shape tolerance, provides resources for the representations of limits within which manufactured shapes are permitted to vary.
This part of ISO 10303 supports all of the dimensioning and tolerancing methods as defined by existing International Standards on technical drawings. These methods include explicit dimensioning, associative dimensioning, plus-minus tolerancing, and geometrical toicrancing.
ISO 1101: l913, Technical drawings – (k’o,rwiric lolerancing – Tolerwicing of form, orientation, location and run-out – Generulittes. definitions, symbols, indications on drawings.
iSO 2692: I9X. Technical drawings- Gc’on,egricaJ tolerancing – Nfati,nun, niuterial principle. ISO 5458:1987, Technical drawings – Geometrical rolerancing – Positional rolerancing.
ISO 5459:1981, Technical drawings – Geometrical tolerancing – Datums and datum-systems for geometrical tolerances.
ISOIIEC 8824-1:1995, Information technology – Abstract Syntax Notation One (ASN.l): Specification of basic notation.
ISO 10303- 1: 1994 Industrial auloniation systems and integration – Product data represenlaiion and excisange – Part I: t)ver’iew and fundamental principles.
ISO I 0303- 11: 1994. Industrial automation systems and integration – Product data representalion and exchange- Part II: l)escription methods: The EXPRESS language reference manual.
TSO 10303-41:1994, Industrial automation ,n’swms and integration – Product data representation and exc’lswsge- Parr 41: Integrated generic resources: Fundamentals of product description and support.
ISO 10303-42:1994, Industrial autoniulion systems and integration – Product data representation and exchange – Parr 42: Integrated generic resource: Geontetric and topological representation.
ISO 10303-43:1994. buiustrüd automation systenls and e?ewgriision – Product data representation and exchange- Part 43: lite grated generic resources: Representation structure.c.
ISO 1057 : 1992, Teclu,ical drawings – Tnlcrancing of orfrmaiio,g and location- Projected tolerance zone.
The subject of the shape_aspect_definition schema is to provide definitions of the spatial cha actenstics of a shape that are required t& dimensioning and tolerancing. This schema provides representations for a derived – shape_aspect and a datum. A derived_shape_aspect is a shape_aspect that is developed thm the defined shape of the product, hut that is not required for defining the product shape. A datum is a shape_ aspect that provide the origin from tiere dimensions and tolerances arc referenced. A dethed_shape_aspect and a datum are aspects ol’thc shapc that arc required for dimensioning and tolerancing the site. the location, the orientation, and the form of a product shape.
4.2 Fundamental concepts and assumptions
The product shape is the concept o shape as a property that characterizes a product. Geometric models and engineering drawings are hwmal methods used to represent the product shape. Dimensions and tolerances are elements othe product shape detinition which are independent from how the shape is represented. Dimensions may he explicitly identified as part of the shape characteristics, implicitly included in a geometric model that represents the shape, or explicitly presented in a twodimcnsional drawing.
A shape_aspect is an elemern of a product shape. Dimensions may be specified for both the entire product shape and aspects of the shape. This schema augments the shape aspects and the relationships aimng them as the definitional mechanism for specifying dimensions and tolerances. A shape aspect. relationships between shape_aspect elements, and their specified dimensions and tolerances are always defined in the context of the product shape property. These dimensions and tolerances can be represented as elements of geometric mtxlels or engineering drawings.
For the purpose of identilying dimensions and tolerances. this schema spccities the concept of a derived shape_ aspect A derived shape aspect is a shape aspect that is defined based on the specific way in which it relates to another shape aspect. The derived shape_aspect is used in conjunction with their related shape_ aspect elements to specify dimensions and tolerances. The specific geometry that can represent the derived shapc_aspect and a shape_aspect that provide the definitional relationship are not in the scope of this schema. The
geometry, thc representation suuuurc, and their a.csociation to the dimension and tolerance elements specified in this part are defined in ISO 10303-41, ISO 10303-42, and ISO 10303-43. Only the generic concept of dcrivcd shape_aspect is pccified here. Application protocols may specify additional derived shape_aspect elements from those provided.
NOTE – Legal values that arc conqu*u sensible for atuihus of entities in this schema may be specified in application protocols.
4.3 shape_aspect_definition_schema type definition: limit_condition
A limit_condition type indicates that a tolerance may have a material modifier condition applicd. This modifier aUo for the addition of matcxial to, or for the reduction of material from a feature. The use of limit condition applies only to tolcranced features and datum features that have size characeristics.
EXAMPLE I The diameter of a hole or of a shaft or the wntth of a slot are size characteristics which may have a liMit_condition applied.
SELFdei1ved_shape_aspect.derIvingre1ationshIps: a shape_aspect_relationship that associates thc shapeaspect wtüdi is extended from other shape_aspects. The relatIng_shape_aspect is the extension. The related_shape_aspect is the basis for the extension.