Appeal No. 1999-2649
Application 08/483,291
temperature somewhat below or about body temperature (37EC).
The temperature of the element is maintained below the
transformation temperature until it is in position, as by
using an insulating sheath. When the element is released from
the sheath it is warmed by the body tissue to a temperature
above its martensite transformation temperature, and reforms
into its coiled form (col. 4, lines 13 to 27). Balko does not
disclose that the SMA used displays SIM, but the examiner,
citing Kirk-Othmer page 731, lines 13 to 20 [sic: 14 to 21],
and page 733, line 6, takes the position that Nitinol can
exhibit SIM (superelastic) properties, and therefore that the
Nitinol disclosed by Balko would inherently have SIM
properties at about body temperature.
The cited portion on page 731 of Kirk-Othmer reads:
The other property peculiar to marmem alloys is
the ability under certain conditions to exhibit
superelastic behavior. Although in one sense, the 3-
8% apparently recoverable strain of the memory
effect is truly an extended or pseudoelastic
behavior, an even further elastic range is possible.
When many of the martensitic alloys are deformed
well beyond the point of the initial single-
coalesced martensite stage, a stress-induced
martensite-martensite transformation can occur. In
this mode of deformation strain is reversible
through stress release and not by a temperature-
4
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 Next
Last modified: November 3, 2007