Coil compression spring

Claim 2

A compression coil spring with progressive spring characteristics, characterized in that the progressivity of the characteristics is realized by ground surfaces in the form of a substantially truncated cone in an otherwise cylindrical coil spring, wherein the axis of said truncated cone extends in the same direction as the cylindrical coil spring longitudinal axis.

Claim 3

A coil spring according to claim 1, characterized in that the ground surfaces are provided on at least one of the two surfaces consisting of internal and external surfaces of the coils of the springs, said internal surfaces facing generally in the direction of the spring longitudinal axis and said external surfaces facing away from the spring longitudinal axis.

Claim 4

A coil spring according to claim 2, characterized in that the ground surfaces of truncated conical shape are provided on both sides of the spring.

Claim 5

A coil spring according to claim 3, characterized in that the ground surfaces extend only over a portion of the spring in relation to its length.

Claim 6

A coil spring according to claim 3, characterized in that the ground surfaces extend substantially over the entire length of the spring.

Claim 7

A coil spring according to claim 1, characterized in that the ground surfaces extend only over a portion of the spring in relation to its length.

Claim 8

A coil spring according to claim 1, characterized in that the ground surfaces extend substantially over the entire length of the spring.

Claim 11

A method according to claim 21, characterized in that both the internal and external surfaces are ground in the shape of a truncated cone.

Claim 12

A method according to claim 9, characterized in that said surfaces are ground in the shape of a truncated cone at least over a part of the length of the spring.

Claim 13

A method according to claim 9, characterized in that said surfaces are ground in a substantially truncated conical shape substantially over the entire length of the spring.

Claim 14

A method according to claim 9, characterized in that said surfaces are ground in the shape of a truncated cone at least over a part of the length of the spring.

Claim 15

A method according to claim 9, characterized in that said surfaces are ground in a substantially truncated conical shape substantially over the entire length of the spring.

Claim 16

A method according to claim 9, characterized in that only one of said two surfaces are ground into the shape of a truncated cone.

Claim 17

A resilient coil spring comprising a continuous member having a plurality of helical windings extending about a centrally disposed longitudinal spring axis for at least a portion of the length of said member, said windings having varying cross-section along at least a portion of said member for providing progressive spring characteristics to said spring, said windings exhibiting internal surface portions facing generally inwardly toward the spring axis and external surface portions facing generally outwardly away from the spring axis, wherein said windings exhibit a maximum cross-section at one position along the length of the longitudinal axis where the internal surface portion is spaced a minimum distance from said spring axis and the external surface portion is spaced a maximum distance from said spring axis, wherein the internal surface portions of all of said windings are spaced from said longitudinal axis at least a distance corresponding to said minimum distance and the external surface portions of all of said windings are spaced from said longitudinal axis at most a distance corresponding to said maximum distance, and wherein the cross-section of said windings is varied by constructing at least one of said internal and external surface portions in the shape of a longitudinally extending truncated cone along at least a portion of the length of the spring.

Claim 18

A resilient coil spring comprising a continuous member having a plurality of helical windings extending about a centrally disposed longitudinal spring axis for at least a portion of the length of said member, said windings having varying cross-section along at least a portion of said member for providing progressive spring characteristics to said spring, said windings exhibiting internal surface portions facing generally inwardly toward the spring axis and external surface portions facing generally outwardly away from the spring axis, wherein said windings exhibit a maximum cross-section at one position along the length of the longitudinal axis where the internal surface portion is spaced a minimum distance from said spring axis and the external surface portion is spaced a maximum distance from said spring axis, wherein the internal surface portions of all of said windings are spaced from said longitudinal axis at least a distance corresponding to said minimum distance and the external surface portions of all of said windings are spaced from said longitudinal axis at most a distance corresponding to said maximum distance, and wherein the cross-section of said windings is varied by constructing at least one of said internal and external surface portions in the shape of a longitudinally extending truncated cone along at least a portion of the length of the spring.

Claim 19

A coil spring according to claim 15, wherein the axis of said truncated cone coincides with said spring axis.

Claim 20

A coil spring according to claim 16, wherein said internal surface portions are constructed in the shape of a truncated cone.

Claim 21

A coil spring according to claim 16, wherein said external surface portions are constructed in the shape of a truncated cone.

Claim 22

A coil spring according to claim 16, wherein both said internal surface portions and said external surface portions are constructed in the shape of a truncated cone.

Claim 23

A coil spring according to claim 15, wherein said coil spring is constructed by grinding the truncated cone shaped surfaces in an otherwise cylindrical coil spring formed with the continuous member of constant cross-section.

Claim 24

A method according to claim 8, wherein the step of forming includes grinding said surfaces.