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G 環球瞭望 LOBAL OUTLOOK
challenge: The company manufactures a lot of
different bearing series, amounting to thousands
of different component geometries, each of which
must be measured to extremely tight tolerances.
To better accommodate these needs, Timken
has added optical metrology to its suite of tactile
gaging technologies.
An Alternative to Comparative Gaging
and CMMs
Comparative-contact gaging, set up to part-
like masters, traditionally has been employed
to measure the outer diameters (ODs) of
axisymmetric components—components that
光學千分（fèn）尺整個測量（liàng）區域 ( 測量（liàng）範圍 VS 區域深度 ) 所測直徑
的映射圖。 are symmetrical along a given axis, like roller
bearings. Comparative gaging is direct, simple
盡。光學千分尺響應頻率高，強製要求錐形或曲
to use and self-compensating for datums and
線形部件提（tí）供的感應麵積小，並且相隔距離大（dà）。
temperature. However, precision masters are
由於沒有任何接觸，所以也不存在部（bù）件變形、偏
costly to manufacture and maintain. In addition,
移或因探頭（tóu）尖部留（liú）下印記的風險。 comparative gages tend to require series-specific
測（cè）量軸承組件直徑（jìng）時，光學千分尺在正規 tooling to fixture the parts for gaging.
測量係統分析測試中的能力已經（jīng）得到證明。拉 As one alternative to comparative gaging,
裏 · 凱勒先生說道（dào） : “與 CMM 相比，光學千分 high-precision coordinate measuring machines
尺能夠達到 1μm 的（de）首項（xiàng）體積精度。” 此外，係統 (CMMs) have been used to measure these bearing
能（néng）夠容忍工（gōng）程內的油汙、 灰塵、 溫度和濕度（dù）變化。 components. As an absolute gage, CMMs do not
從費用開銷和（hé）循（xún）環時間（jiān）而言，其成本也比討論（lùn）的 require part-like masters and usually do not require
其他測（cè）量方式低 ( 比較式或絕對式 )。 series-specific tooling for measurement. However,
factors such as maintenance, recertification and
【英文如下】 sequence programming can cause the initial
The humble bearing may just be one of the capital cost and overall cost of ownership to trend
least-sung of unsung heroes. But bearings are high. Also, CMM measurement cycle times can be
important not only for manufacturers whose much longer than those of comparative gaging.
advanced equipment relies on them for smooth Not only that, but some parts are susceptible to
and reliable motion, but for too many machines deformation, deflection or marking from the CMM
(and their users) to number. probe tip contact force. These are unacceptable
Bearings are also paramount to The Timken conditions for Timken, which requires the utmost
Co., headquartered in North Canton, Ohio. The precision and fast cycle times to stay competitive.
company is a global leader in friction-management An alternative that addresses the
technologies and offers one of the most complete shortcomings of both comparative gaging and
lines of anti-friction bearings in the industry. CMMs is the optical micrometer. According to
This longstanding success has led to a gaging Larry Keller, metrology and gaging technologist ·84· 第08期 數控（kòng）機床市（shì）場