Inserted blade cutting tool with locking pin

Claim 2

The combination of a wafer-like cutting insert, an insert holder and means for locking said insert to said holder, said holder having an upwardly facing platform for supporting the lower face of said insert and having an inner abutment projecting upwardly from said platform for engaging one edge Of said insert to locate the latter in a cutting position, a generally cylindrical opening extending through said insert and having an axis extending substantially perpendicular to said platform, a hole formed in said holder and opening out of the upper side of said platform, said hole having an axis which diverges outwardly away from said abutment as it progresses upwardly and which is inclined at a predetermined angle relative to the axis of said opening, said locking means comprising a pin having a lower shank extending into and adapted to be tightened within said hole, and said pin having an upper head of generally circular cross-section and sized and shaped such that the lower end portion of the head engages the inner wall of said opening to crowd said insert edgewise against said abutment and clamps said insert to said platform while the upper end portion of said head engages the outer wall of said opening to limit bending of said pin and to help clamp said insert to said platform.

Claim 3

The combination of a wafer-like cutting insert, an insert holder and means for locking said insert to said holder, said holder having an upwardly facing platform for supporting the lower face of said insert and having an inner abutment projecting upwardly from said platform for engaging one edge of said insert to locate the latter in a cutting position, a generally cylindrical opening extending through said insert and having an axis c extending substantially perpendicular to said platform, a hole formed in said holder and opening out of the upper side of said platform, said hole having an axis a which diverges outwardly away from said abutment as it progresses upwardly and which is inclined at a predetermined acute angle b relative to the axis c of said opening, said locking means comprising a pin having an axis coinciding with said axis a of said hole and having a lower shank extending into and adapted to be tightened within said hole, said pin including an upper head of generally circular cross-section disposed within said opening and sized and shaped such that the lower end portion of the head engages the inner wall of said opening to crowd said insert edgewise against said abutment and clamps said insert to said platform while the upper end portion of said head engages the outer wall of said opening to reduce bending of said pin and to help clamp said insert to said platform, the sizing and shaping of said head being such that: A. the uppermost contact point between the lower end portion of said head and the inner wall of said opening is not above the intersection point f of said axes a and c and is spaced from said axis a along a radius of dimension R1, B. the lowermost contact point between the upper end portion of said head and the outer wall of said opening is not below the intersection point f and is spaced from said axis a along a radius of dimension R2, C. the lowermost contact point and the uppermost contact point are spaced along the axis a from the intersection point f by distances D1 and D2, respectively, which are not less than: r sin b where r is the minimum radius of said opening, D. the dimensions R1 and R2 are not greater than: r cos b, and E. the distances D1 and D2 are related to the dimensions R1 and R2, respectively, substantially in accordance with the functions: D1 r sin b + (r cos b - R1)/tan b D2 r sin b + (r cos b - R2)/tan b

Claim 4

The combination of a wafer-like cutting insert, an insert holder and means for locking said insert to said holder, said holder having an upwardly facing platform for supporting the lower face of said insert and having an inner abutment projecting upwardly from said platform for engaging one edge of said insert to locate the latter in a cutting position, a generally cylindrical opening extending through said insert and having an axis c extending substantially perpendicular to said platform, a hole formed in said holder and opening out of the upper side of said platform, said hole having an axis a which diverges outwardly away from said abutment as it progresses upwardly and which is inclined at a predetermined acute angle b relative to the axis c of said opening, said locking means comprising a pin having an axis coinciding with said axis a of said hole and having a lower shank extending into and adapted to be tightened within said hole, said pin including an upper head of generally circular cross-section disposed within said opening and sized and shaped such that the lower end portion of the head engages the inner wall of said opening to crowd said insert edgewise against said abutment and clamps said insert to said platform while the upper end portion of said head engages the outer wall of said opening to reduce bending of said pin and to help clamp said insert to said platform, the sizing and shaping of said head being such that: A. the uppermost contact point between the lower end portion of said head and the inner wall of said opening is not above the intersection point f of said axes a and c and is spaced from said axis a along a radius of dimension R1, B. the lowermost contact point between the upper end portion of said head and the outer wall of said opening is not below the intersection point f and is spaced from said axis a along a radius of dimension R2, C. the lowermost contact point and the uppermost contact point are spaced along the axis a from the intersection point f by distances D1 and D2, respectively, which are not less than: r sin b where r is the minimum radius of said opening, D. the dimensions R1 and R2 are not greater than: r cos b, and E. the distances D1 and D2 are related to the dimensions R1 and R2, respectively, substantially in accordance with the functions: D1 r sin b + (r cos b - R1)/tan b D2 r sin b + (r cos b - R2)/tan b

Claim 5

A locking pin adapted to extend through a generally cylindrical opening in a cutting insert and operable to clamp the insert to an insert holder, said pin having an axis a inclined at a pRedetermined acute angle b relative to the axis of said opening, having a threaded shank adapted to be screwed into said holder and having a head of generally circular cross-section positionable in said opening, said head being sized and shaped such that: A. one radius of dimension R1 of said head contacts one wall of the opening at a first contact point while a second radius of dimension R2 contacts a diametrically opposite wall of said opening at a second contact point spaced along said axis a from said first contact point, and B. the spacing between said contact points along said axis a is substantially equal to: 2r sin b + (r cos b - R1)/tan b + (r cos b - R2)/tan b where r is the minimum radius of said opening.

Claim 6

A locking pin adapted to extend through a generally cylindrical opening in a cutting insert and operable to clamp the insert to an insert holder, said pin having an axis a inclined at a pRedetermined acute angle b relative to the axis of said opening, having a threaded shank adapted to be screwed into said holder and having a head of generally circular cross-section positionable in said opening, said head being sized and shaped such that: A. one radius of dimension R1 of said head contacts one wall of the opening at a first contact point while a second radius of dimension R2 contacts a diametrically opposite wall of said opening at a second contact point spaced along said axis a from said first contact point, and B. the spacing between said contact points along said axis a is substantially equal to: 2r sin b + (r cos b - R1)/tan b + (r cos b - R2)/tan b where r is the minimum radius of said opening.

Claim 7

A locking pin as defined in claim 3 in which said head is formed with rounded surfaces at said contact points.

Claim 8

A locking pin as defined in claim 3 in which said head is formed with oppositely tapered frustums.

Claim 9

The combination of a wafer-like cutting insert, an insert holder and means for locking said insert to said holder, said holder having an upwardly facing platform for supporting the lower face of said insert and having an inner abutment projecting upwardly from said platform for engaging one edge of said insert to locate the latter in a cutting position, an opening of circular cross-section extending through said insert and having an axis extending substantially perpendicular to said platform, a threaded hole formed in said holder and opening out of the upper side of said platform, said hole having an axis which diverges outwardly away from said abutment as it progresses upwardly and which is inclined at a predetermined angle relative to the axis of said opening, said locking means comprising a pin having a lower shank threaded into said hole, the upper end portion of said pin having a lower frusto-conical section which tapers downwardly and wedges against the inner wall of said opening to crowd said insert edgewise against said abutment while clamping said insert to said platform, and the upper portion of said pin having an upper frusto-conical section which tapers upwardly and wedges against the outer wall of said opening to reduce bending of the pin at the junction of said upper end portion and said shank and to help clamp the insert to said platform.

Claim 10

The combination of a wafer-like cutting insert, an insert holder and means for locking said insert to said holder, said holder having an upwardly facing platform for supporting the lower face of said insert and having an inner abutment projecting upwardly from said platform for engaging one edge of said insert to locate the latter in a cutting position, an opening of circular cross-section extending through said insert and having an axis extending substantially perpendicular to said platform, a threaded hole formed in said holder and opening out of the upper side of said platform, said hole having an axis which diverges outwardly away from said abutment as it progresses upwardly and which is inclined at a predetermined angle relative to the axis of said opening, said locking means comprising a pin having a lower shank threaded into said hole, the upper end portion of said pin having a lower frusto-conical section which tapers downwardly and wedges against the inner wall of said opening to crowd said insert edgewise against said abutment while clamping said insert to said platform, and the upper portion of said pin having an upper frusto-conical section which tapers upwardly and wedges against the outer wall of said opening to reduce bending of the pin at the junction of said upper end portion and said shank and to help clamp the insert to said platform.

Claim 11

The combination defined in claim 6 in which the upper end portion of said pin includes a cylindrical section located between said upper and lower frusto-conical sections.

Claim 12

The combination defined in claim 7 in which the diameter of said cylindrical section is equal to the major diameters of said frusto-conical sections and is just slightly less than the diameter of said opening.

Claim 13

The combination defined in claim 8 in which the axis of said opening intersects the axis of said hole at approximately the center of said cylindrical section.

Claim 14

The combination defined in claim 8 in which the cone angle of said lower frusto-conical section is approximately equal to the cone angle of said upper frusto-conical section and is approximately equal to said predetermined angle whereby the inner side of said lower frusto-conical section substantially parallels the inner wall of said opening and the outer side of said upper frusto-conical section substantially parallels the outer wall of said opening.

Claim 15

The combination defined in claim 6 in which the cone angle of said lower frusto-conical section is approximately equal to the cone angle of said upper frusto-conical section and is approximately equal to said predetermined angle whereby the inner side of said lower frusto-conical section substantially parallels the inner wall of said opening and the outer side of said upper frusto-conical section substantially parallels the outer wall of said opening.

Claim 16

The combination definEd in claim 6 in which said pin includes a generally cylindrical neck smaller in diameter than said shank and smaller in diameter than the minor diameter of said lower frusto-conical section, said neck being located between said shank and said lower frusto-conical section.

Claim 17

The combination defined in claim 12 further including a shim sandwiched between said insert and said platform, said shim being formed with a bore for receiving said pin and having one wall engageable with the pin to prevent edgewise removal of the shim from the pin, a counterbore at the upper end of said bore, and a washer seated in said counterbore and formed with an opening whose edges embrace said neck and are engageable with the lower end of said lower frusto-conical section to restrict upward removal of said shim from the upper end portion of said pin when the latter is loosened and said insert is removed from said holder.

Claim 18

The combination as defined in claim 13 in which said washer is made of resiliently yieldable material, the opening in said washer having a relaxed diameter smaller than the major diameter of said lower frusto-conical section and being stretchable to permit insertion of the washer onto the pin.

Claim 19

The combination defined in claim 14, in which the opening in said washer is located eccentrically of the washer to accommodate said pin.

Claim 20

The combination defined in claim 13 in which the opening in said washer comprises a slot opening out of one edge of the washer, said slot having a width greater than the diameter of said neck and smaller than the major diameter of said lower frusto-conical section.

Claim 21

A locking pin for clamping a cutting insert to an insert holder, said pin comprising a threaded shank, a first frusto-conical section located near one end of said shank and tapering toward the shank, and a second frusto-conical section located near the larger end of said first section and tapering away from said shank.

Claim 22

A locking pin for clamping a cutting insert to an insert holder, said pin comprising a threaded shank, a first frusto-conical section located near one end of said shank and tapering toward the shank, and a second frusto-conical section located near the larger end of said first section and tapering away from said shank.

Claim 23

A locking pin as defined in claim 17 in which the cone angles of said frusto-conical sections are approximately equal.

Claim 24

A locking pin as defined in claim 18 which includes a cylindrical section located between said frusto-conical sections.

Claim 25

A locking pin as defined in claim 19 in which the major diameter of said first frusto-conical section is equal to the diameter of said cylindrical section and to the major diameter of said second frusto-conical section.

Claim 26

A locking pin as defined in claim 20 further including a generally cylindrical neck smaller in diameter than said shank and the minor diameter of said first frusto-conical section, said neck being located between said shank and said first frusto-conical section.