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BP01: Specification
of Drawing Data and Associated Tolerances for Involute Gears:
Good drawing practice generally requires that all data needed
by the manufacturer (and the inspector) should appear explicitly
on the drawing and that no piece of information should be
duplicated. The nature of gear geometry and the multiplicity
of manufacturing and inspection processes often makes it difficult,
if not impossible, to follow these precepts fully. They also
create difficulty in attempting to completely standardise
either the layout of the information on the drawing or the
content. To help with this difficulty, the data required has
been divided into sections and each section is covered by
one of the clauses in this book. |
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BP02: Specification
of Gear Blanks for Involute Gears:
The numerical values of the parameters associated with gear
tooth accuracy (profile error, adjacent pitch error, etc.,)
are only meaningful relative to a particular axis of rotation.
If the axis about which the gear is rotated during measurement
is changed, then the measured value of these parameters will
change. It follows that the gear drawing must define an axis
which is to act as the reference axis for the specified tooth
tolerances, and in fact for the gear geometry as a whole.
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BP03.1: Involute Gear Measurement:
It is intended to formalise the procedures used for measuring
lead, profile and pitch errors in involute gears using dedicated
gear measuring machines and CMM's with gear measurement
software.
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BP03.2:
Interpretation of Measurements:
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BP04: Checking
the Reproducibility of Gear Measuring Machines:
It is very important that the accuracy of gear inspection
equipment is assessed frequently to ensure that it is suitable
for the final inspection of gears: the quality and accuracy
of the gears being manufactured depend on its accuracy.
BP04 specifies simple routine tests to enable the gear inspector
to verify that the accuracy of the machine is maintained.
The tests check the reproducibility and stability of the machine
between the full accuracy verification tests specified in
BP05. |
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BP05.1: Verifying the
Accuracy of Gear Measuring Machines: Part 1:
Specifies the general requirements and procedures to be used
to verify the accuracy and measurement uncertainty of a gear
measuring machine and demonstrate traceability to National
Standards. The procedures involve functional tests with traceably
calibrated gear artefacts and tests on those individual elements
of the machine which are known to cause significant measuring
errors. Part 1 (BP05.1): Specifies the requirements
and tests which are necessary to verify the accuracy of any
gear measuring machine. The principal tests are based on traceably
calibrated gear artefacts. These tests limit the size of the
traceably verified measuring volume to that of the size of
the gear artefacts used for the tests. |
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BP05B: Verifying the
Accuracy of Gear Measuring Machines: Part 2:
Specifies the general requirements
and procedures to be used to verify the accuracy and measurement
uncertainty of a gear measuring machine and demonstrate traceability
to National Standards. The procedures involve functional tests
with traceably calibrated gear artefacts and tests on those
individual elements of the machine which are known to cause
significant measuring errors. Part 2 (BP05.2): Specifies
the additional tests necessary to increase the traceably verified
measuring volume to allow the measurement of gears of up to
twice the size of the largest artefacts used for the tests
in PART 1. |
