Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
214 words
A catheter tip pressure transducer for use in measuring fluid pressure within a living body, comprising; a tubular housing having a pressure inlet aperture formed therein; a semiconductor block carried within said housing and having first and second oppositely directed major surfaces, one of which faces said inlet aperture; said first surface having a recess defined therein such that the floor of said recess and said second surface define therebetween a relatively thin rectangular portion having a length l, a width b and a thickness d; said second surface having a pair of longitudinally extending grooves, each of a length l, defined therein in registry with the longitudinal side edges of said rectangular portion so as to define therebetween an elongated longitudinally extending rectangular membrane beam of a length l, a width s which is less than width b and a thickness d with said membrane beam acting as a free beam supported in the longitudinal direction at its opposite ends by and integral with said semiconductor block and relatively unsupported in the lateral direction such that applied pressure results mainly in longitudinal deformations of said membrane beam; and strain gauge means carried by said membrane beam and responsive to said longitudinal deformation thereof for providing an output indication representative of said applied pressure.
Claim 2
Dependent Claim
214 words
A catheter tip pressure transducer for use in measuring fluid pressure within a living body, comprising; a tubular housing having a pressure inlet aperture formed therein; a semiconductor block carried within said housing and having first and second oppositely directed major surfaces, one of which faces said inlet aperture; said first surface having a recess defined therein such that the floor of said recess and said second surface define therebetween a relatively thin rectangular portion having a length l, a width b and a thickness d; said second surface having a pair of longitudinally extending grooves, each of a length l, defined therein in registry with the longitudinal side edges of said rectangular portion so as to define therebetween an elongated longitudinally extending rectangular membrane beam of a length l, a width s which is less than width b and a thickness d with said membrane beam acting as a free beam supported in the longitudinal direction at its opposite ends by and integral with said semiconductor block and relatively unsupported in the lateral direction such that applied pressure results mainly in longitudinal deformations of said membrane beam; and strain gauge means carried by said membrane beam and responsive to said longitudinal deformation thereof for providing an output indication representative of said applied pressure.
Claim 3
Dependent Claim
58 words
A transducer as set forth in claim 1, wherein said pair of grooves extend through said rectangular portion defining longitudinally extending slots bordering the longitudinally extending side edges of said membrane beam, a coating layer overlying said slots on said second surface and adhering thereto so as to permit a pressure differential across said first and second surfaces.
Claim 4
Dependent Claim
17 words
A transducer as set forth in claim 2, wherein said coating layer is of a polymer material.
Claim 5
Dependent Claim
51 words
A transducer as set forth in claim 1 wherein said grooves are each rectangular in shape having a width c and a depth on the order of 1/2 d, said grooves overlap the corresponding longitudinal edges of said rectangular portion on either side thereof by a distance of approximately 1/2 c.
Claim 6
Dependent Claim
24 words
A transducer as set forth in claim 4 wherein the width s of said membrane beam is on the order of width b-width c.
Claim 7
Dependent Claim
49 words
A transducer as set forth in claim 1 wherein said strain gauge means includes four elongated piezoelectric resistors connected together to define a Wheatstone bridge circuit and with each resistor being located on said membrane beam and oriented so as to extend parallel to the longitudinal side edges thereof.
Claim 8
Dependent Claim
30 words
A transducer as set forth in claim 6, including a rigid support member of insulating material located in said housing, said semiconductor block being rigidly secured to said support member.
Claim 9
Dependent Claim
27 words
A transducer as set forth in claim 1, wherein said first surface faces said inlet aperture and said strain gauge means are located on said second surface.