Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
181 words
An endoscopic surgical cutting instrument comprising: (a) a handle assembly; (b) a body portion extending from said handle assembly and defining a generally central longitudinal axis; and (c) a pair of cutting blade members including a first blade member and a second blade member pivotally connected to each other to open and close about a common pivot axis in response to movement of said handle assembly, each cutting blade member having a cutting edge which faces the cutting edge of the other cutting blade member and a generally curved crescent-shaped cross-section in a plane defined by said pivot axis and said longitudinal axis; and wherein said generally crescent-shaped first blade member has a radius of curvature and said generally crescent-shaped second blade member has a radius of curvature, a center of the radius of curvature of said first blade member being offset from a center of the radius of curvature of said second blade member by a predetermined distance measured along said longitudinal axis such that said first and second blade members contact each other during opening and closing movement thereof.
Claim 2
Dependent Claim
181 words
An endoscopic surgical cutting instrument comprising: (a) a handle assembly; (b) a body portion extending from said handle assembly and defining a generally central longitudinal axis; and (c) a pair of cutting blade members including a first blade member and a second blade member pivotally connected to each other to open and close about a common pivot axis in response to movement of said handle assembly, each cutting blade member having a cutting edge which faces the cutting edge of the other cutting blade member and a generally curved crescent-shaped cross-section in a plane defined by said pivot axis and said longitudinal axis; and wherein said generally crescent-shaped first blade member has a radius of curvature and said generally crescent-shaped second blade member has a radius of curvature, a center of the radius of curvature of said first blade member being offset from a center of the radius of curvature of said second blade member by a predetermined distance measured along said longitudinal axis such that said first and second blade members contact each other during opening and closing movement thereof.
Claim 3
Dependent Claim
17 words
An instrument according to claim 1, further comprising means for urging said blade members toward each other.
Claim 4
Dependent Claim
28 words
An instrument according to claim 1, wherein a first blade member is stationary and a second blade member is pivotable in response to movement of said handle assembly.
Claim 5
Dependent Claim
36 words
An instrument according to claim 1, wherein the radius of curvature of said first blade member at said cutting edge is equal to the radius of curvature of said second blade member at said cutting edge.
Claim 6
Dependent Claim
52 words
An instrument according to claim 1, wherein said blade members contact each other during opening and closing at a single contact point along a length of said cutting edges to enhance shearing of tissue and thereby to define a gap between said blade members from said pivot axis to said contact point.
Claim 7
Dependent Claim
23 words
An instrument according to claim 5, wherein said gap is between about 0.015 inches and 0.025 inches when said blade members are closed.
Claim 8
Dependent Claim
48 words
An instrument according to claim 1, wherein said body portion comprises an outer tube member and an inner rod member slidably positioned within said tube member, said inner rod operably connected to said handle assembly and said pair of blade members to open and close said blade members.
Claim 9
Dependent Claim
22 words
An instrument according to claim 7, wherein said blade members are secured about said common pivot axis to said outer tube member.
Claim 10
Dependent Claim
41 words
An instrument according to claim 1, wherein said center of said radius of curvature of said first blade member is offset from said center of said radius of curvature of said second blade member between about 0.025 inches and 0.040 inches.
Claim 11
Dependent Claim
19 words
An instrument according to claim 9, wherein said centers of said radii of curvature are offset about 0.032 inches.
Claim 12
Dependent Claim
29 words
An instrument according to claim 1, wherein said blade members contact each other progressively at a plurality locations during opening and closing movement thereof for enhancing shearing of tissue.
Claim 13
Dependent Claim
50 words
An instrument according to claim 11, wherein said tissue shearing enhancing means comprises an inside surface of each blade member being angled toward said cutting edge to define a relief angle, said inside surfaces of said blade members facing each other when said blade members are in said closed position.
Claim 14
Dependent Claim
14 words
An instrument according to claim 12, wherein said relief angle is less than 5°.
Claim 15
Dependent Claim
15 words
An instrument according to claim 12, wherein said relief angle is between 2° and 3°.
Claim 16
Dependent Claim
17 words
An instrument according to claim 12, further comprising means for urging said blade members toward each other.
Claim 17
Dependent Claim
16 words
An instrument according to claim 15, wherein said blade member urging means comprises a spring washer.
Claim 18
Dependent Claim
239 words
An endoscopic surgical cutting instrument comprising: a) a handle assembly; b) a body portion extending from said handle assembly and defining a generally central longitudinal axis; and c) a pair of cutting blade members including a first blade member and a second blade member, pivotally connected to each other and being operable to open and close about a common pivot axis in response to movement of said handle assembly, said first blade member having a top edge and an opposed bottom cutting edge, and said second blade member having a bottom edge and an opposed top cutting edge, said blade members being positioned at an end of said body portion opposite said handle assembly and having generally curved crescent-shaped cross-sections in a plane defined by said pivot axis and said longitudinal axis; wherein said generally crescent-shaped blade members each has an inside surface facing each other when in a closed position, said inside surface of said first blade member being angled from said top edge toward said bottom cutting edge to define a first relief angle, said inside surface of said second blade member being angled from said bottom edge toward said top cutting edge to define a second relief angle, said first and second relief angles cooperating to maintain said bottom cutting edge of said first blade member in contact with said top cutting edge of said second blade member during opening and closing of said blade members.
Claim 19
Dependent Claim
239 words
An endoscopic surgical cutting instrument comprising: a) a handle assembly; b) a body portion extending from said handle assembly and defining a generally central longitudinal axis; and c) a pair of cutting blade members including a first blade member and a second blade member, pivotally connected to each other and being operable to open and close about a common pivot axis in response to movement of said handle assembly, said first blade member having a top edge and an opposed bottom cutting edge, and said second blade member having a bottom edge and an opposed top cutting edge, said blade members being positioned at an end of said body portion opposite said handle assembly and having generally curved crescent-shaped cross-sections in a plane defined by said pivot axis and said longitudinal axis; wherein said generally crescent-shaped blade members each has an inside surface facing each other when in a closed position, said inside surface of said first blade member being angled from said top edge toward said bottom cutting edge to define a first relief angle, said inside surface of said second blade member being angled from said bottom edge toward said top cutting edge to define a second relief angle, said first and second relief angles cooperating to maintain said bottom cutting edge of said first blade member in contact with said top cutting edge of said second blade member during opening and closing of said blade members.
Claim 20
Dependent Claim
14 words
An instrument according to claim 17, wherein said relief angle is less than 5°.
Claim 21
Dependent Claim
14 words
An instrument according to 17, wherein said relief angle is between 2° and 3°.
Claim 22
Dependent Claim
14 words
An instrument according to 17, wherein said relief angle is between 2° and 3°.
Claim 23
Dependent Claim
38 words
An instrument according to claim 17, wherein said blade members are metal injection molded and said relief angle is ground into said blade members after molding of said blade members to enhance shearing action of said blade members.
Claim 24
Dependent Claim
58 words
An instrument according to claim 17, wherein said blade members have different centers of radii of curvature relative to said common pivot axis, said centers of said radii of curvature being offset a predetermined distance along said longitudinal axis, such that during opening and closing said cutting edges contact at a single point to enhance shearing of tissue.
Claim 25
Dependent Claim
37 words
An instrument according to claim 21, wherein said blade members contact each other during opening and closing at said single point to define a gap between said blade members from said pivot axis to said contact point.
Claim 26
Dependent Claim
201 words
An endoscopic surgical instrument comprising: a) a handle assembly; b) a body portion extending from said handle assembly defining a longitudinal axis of said instrument; and c) a pair of cutting blade members including a first blade member and a second blade member connected to each other to open and close about a common pivot axis in response to movement of said handle assembly, each cutting blade member having a cutting edge which faces the cutting edge of the other cutting blade member and a generally curved crescent-shaped cross-section in a plane defined by said pivot axis and said longitudinal axis; wherein said first curved generally crescent-shaped blade member has a first radius of curvature and said second curved generally crescent-shaped blade member has a second radius of curvature, said first and second radii of curvature being unequal, a center of said first radius of curvature being offset from a center of said second radius of curvature by a predetermined distance measured along said longitudinal axis, such that during opening and closing of said blade members, said first blade member contacts said second blade member progressively along a length of said cutting edges in a manner to enhance shearing of tissue.
Claim 27
Dependent Claim
201 words
An endoscopic surgical instrument comprising: a) a handle assembly; b) a body portion extending from said handle assembly defining a longitudinal axis of said instrument; and c) a pair of cutting blade members including a first blade member and a second blade member connected to each other to open and close about a common pivot axis in response to movement of said handle assembly, each cutting blade member having a cutting edge which faces the cutting edge of the other cutting blade member and a generally curved crescent-shaped cross-section in a plane defined by said pivot axis and said longitudinal axis; wherein said first curved generally crescent-shaped blade member has a first radius of curvature and said second curved generally crescent-shaped blade member has a second radius of curvature, said first and second radii of curvature being unequal, a center of said first radius of curvature being offset from a center of said second radius of curvature by a predetermined distance measured along said longitudinal axis, such that during opening and closing of said blade members, said first blade member contacts said second blade member progressively along a length of said cutting edges in a manner to enhance shearing of tissue.
Claim 28
Dependent Claim
41 words
An instrument according to claim 23, wherein said cutting edge of said first cutting blade member is defined by said first radius of curvature and said cutting edge of said second blade member is defined by said second radius of curvature.