Beschreibung

The basic plate of a measuring device is specified.

A functional datum system must be defined and the hole pattern for fiaxtion of the workpiece carriers should be described as precisely as possible. Therefore multi-level pattern specifications are applied.

In variant 2 a datum system is described which, in contrast to variant 1, does not consist of slots but only of bores. This leads to challenges in terms of functional description, which create the need to use the latest specification elements (situation features, datum system system identifier) according ISO 5459:2024.

Length of explanation video (Step by Step guide) : Approx. 40 min.

Variants: Yes

Difficulty Level: Variant 1: Suitability 1-2 | Variant 2: Suitability 2-4

Description of the level of difficulty (suitability for the user):

1 – The user has basic knowledge but has not yet used ISO GPS frequently in practice and takes first steps.

2 – The user has basic knowledge but is not proof about using ISO GPS and would like to gain more general confidence.
More „special“ or complex modifiers (these are usually listed in the example description) are applied selectively.

3 – The user has sufficient knowledge, can already use frequently used ISO GPS tools without difficulty,
and would like to deepen knowledge selectively based on typical functional descriptions,
which is usually also product-specific (e.g., snapping features (latching hooks) on a plastic injection-molded part, special demand hole patterns, i.e. multi-level patterns etc.)
used in the example (i.e., listed in the description) (e.g., direction only or certain combinations of dimensional tolerancing, as well as SIM or similar modifications).

4 – The user has extensive knowledge, has been working with ISO GPS for a long time,
and would like to learn about very specific applications or modification operations, which usually describe more complex functional requirements and products.
This requires, for example, situation features, reference elements, filter information, association modifiers etc.

Used specification modifiers

In addition to the commonly used tools (profile, position, datums, etc.), the following modifiers were used:

Envelope requirement (Taylor principle)
GX modifier – Maximum inscribed size
CZ modifier – Combined zone (Common zone)
SZ – Separate zones
Restrictive specifications
>< – For orientation constraint only (Direction only) modifier
Common datum
Datum targets
Situation features (e.g. [SL] )
DV – Distance variable
Datum system identifier (e.g. DS1)
Multi-level single indicator pattern specification (e.g. SZ CZ)

Standards

The following standards are helpful or have been used:

ISO 129-1 Technical product documentation (TPD) – Presentation of dimensions and tolerances
ISO 1101 Geometrical tolerancing – Tolerances of form, orientation, location and run-out
ISO 1660 Geometrical tolerancing – Profile tolerancing
ISO 14405-1: Dimensional tolerancing – Linear sizes
ISO 5459 Geometrical tolerancing – Datums and datum systems
ISO 22081 Geometrical tolerancing – General geometrical specifications and general size specifications