Pressure gauge and system

Claim 2

A pressure gauge comprising: a body having a piston chamber disposed therein partially defined by a piston chamber wall; a piston disposed in said piston chamber and reciprocally movable therein, said piston having a first gasket and a second gasket coupled thereto and engaging said chamber wall, said first gasket and said second gasket partially defining a first inter-gasket pressure chamber therebetween, said piston having a piston channel therein, said piston channel communicating said piston chamber with said first inter-gasket pressure chamber; and means for measuring pressure in said piston chamber coupled to said body.

Claim 3

The gauge of claim 1 wherein said piston further includes a first radial disc, a second radial disc, a third radial disc, and a fourth radial disc, wherein said first gasket is a first O-ring disposed between said first radial disk and said second radial disc, and wherein said second gasket is a second O-ring disposed between said third radial disc and said fourth radial disc.

Claim 4

The gauge of claim 2 wherein said piston channel includes an unobstructed longitudinal piston bore and an unobstructed radial piston bore.

Claim 5

The gauge of claim 3 wherein said piston has a first surface and a second surface, said piston channel penetrating said first surface, said second surface being unpenetrated by said piston channel.

Claim 6

The gauge of claim 4 wherein said piston chamber wall is completely cylindrical between said first gasket and said second gasket.

Claim 7

The gauge of claim 5 wherein said piston further includes a third gasket coupled thereto and engaging said piston chamber wall, said third gasket and said second gasket partially defining a second inter-gasket pressure chamber therebetween.

Claim 8

The gauge of claim 6 wherein said second inter-gasket pressure chamber communicates with said piston chamber.

Claim 9

The gauge of claim 7 wherein said piston comprises aluminum.

Claim 10

The gauge of claim 8 wherein said first O-ring is made of neoprene rubber, and wherein said second O-ring is made of neoprene rubber.

Claim 11

The gauge of claim 9 and further comprising: a main line housing coupled to said body and adapted to be coupled to a fluid pressure supply source; and a balloon catheter coupled to said main line housing.

Claim 12

The gauge of claim 1 wherein said piston channel includes an obstructed longitudinal piston bore and an unobstructed radial piston bore.

Claim 13

The gauge of claim 1 wherein said piston has a first surface and a second surface, said piston channel penetrating said first surface, said second surface being unpenetrated by said piston channel.

Claim 14

The gauge of claim 1 wherein said piston chamber wall is completely cylindrical between said first gasket and said second gasket.

Claim 15

The gauge of claim 1 wherein said piston further includes a third gasket coupled thereto and engaging said piston chamber wall, said third gasket and said second gasket partially defining a second inter-gasket pressure chamber therebetween.

Claim 16

The gauge of claim 1 wherein said second inter-gasket pressure chamber communicates with said piston chamber.

Claim 17

The gauge of claim 1 wherein said piston comprises aluminum.

Claim 18

The gauge of claim 1 wherein said first gasket is made of neoprene rubber, and wherein said second gasket is made of neoprene rubber.

Claim 19

The gauge of claim 1 and further comprising: a main line housing coupled to said body and adapted to be coupled to a fluid pressure supply source; and a balloon catheter coupled to said main line housing.

Claim 20

In combination: a sterilized balloon catheter; means for supplying sterilized fluid coupled to said balloon catheter, said means for supplying fluid providing a sterilized working fluid to said balloon catheter; and a sterilized pressure gauge operably coupled to said balloon catheter and including: (a) a body having a sterilized piston chamber disposed therein partially defined by a piston chamber wall; (b) a piston disposed in said piston chamber and reciprocally movable therein, said piston having a first gasket and a second gasket coupled thereto and engaging said chamber wall, said first gasket and said second gasket and said piston chamber wall and said piston define an inter-gasket pressure chamber therebetween; and (c) means for measuring pressure in said piston chamber coupled to said body and isolated from said inter-gasket pressure chamber, said means for measuring containing a corrosion contaminated fluid above and in direct contact with said piston, wherein said working fluid from said means for supplying fluid contacting said piston, said piston providing a seal between said working fluid and said corrosion contaminated fluid.

Claim 21

In combination: a sterilized balloon catheter; means for supplying sterilized fluid coupled to said balloon catheter, said means for supplying fluid providing a sterilized working fluid to said balloon catheter; and a sterilized pressure gauge operably coupled to said balloon catheter and including: (a) a body having a sterilized piston chamber disposed therein partially defined by a piston chamber wall; (b) a piston disposed in said piston chamber and reciprocally movable therein, said piston having a first gasket and a second gasket coupled thereto and engaging said chamber wall, said first gasket and said second gasket and said piston chamber wall and said piston define an inter-gasket pressure chamber therebetween; and (c) means for measuring pressure in said piston chamber coupled to said body and isolated from said inter-gasket pressure chamber, said means for measuring containing a corrosion contaminated fluid above and in direct contact with said piston, wherein said working fluid from said means for supplying fluid contacting said piston, said piston providing a seal between said working fluid and said corrosion contaminated fluid.