Appeal No. 95-2533
Application No. 08/018,125
flexible wall of the obturator disclosed therein (see substitute
brief, page 6).
We are unpersuaded by the appellant’s contention. The Swiss
patent discloses a wad or obturator wherein air is compressed
within a barrier means during the absorption of the shock of
recoil when a projectile is fired (see pages 1 and 3). This wad
or obturator is described as being formed of
two pieces (1 and 2), each in the shape of a hollow
cylinder provided with a single bottom, fitting one
inside the other. The exterior wall of the exterior
piece (1) is cylindrical and has ring-shaped sealing
flanges (3), whereas its interior wall is slightly
truncated, and flared towards its opening. The
exterior wall of the interior piece (2) has the same
conicity that the interior wall of the piece (1) has
and the dimensions of the two pieces are such that when
they are set inside one another, the bottom of the
interior piece is flush with the bottom of the exterior
piece and the edge of the interior piece is at a
certain distance from the bottom of the exterior piece
(figure 2). [See the paragraph bridging pages 2 and 3
of the translation.]
After noting that the two pieces are made of a material
having flexibility and elasticity, the Swiss patent does
thereafter state that the exterior piece becomes distended by the
interaction between the tapering surfaces during firing of the
projectile in order to effect a seal between the wad or obturator
and the barrel of a gun. However, it is further stated in the
Swiss patent that “a cushion of air is trapped between the two
11
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007