Method for producing a nonlinear cylindrical spring and use of such a spring

1 . A method for producing a spring for use in a valve for setting a travel path of an actuator, the method comprising:

providing a blank of wire to be formed into a spring wire, the blank having a constant diameter over a length thereof;

providing a shaping device configured as a drum roller including:

an inner rotor rotatable about a central longitudinal axis and having an outer lateral surface;

an outer drum surrounding the inner rotor and being concentric with the inner rotor, the outer drum having an inner lateral surface facing the outer lateral surface;

an annular gap positioned between the outer lateral surface and the inner lateral surface, the annular gap having an input side and an output side and tapering continuously from the input side to the output side;

wherein a width of the annular gap, viewed in a radial direction, is:

at the input side, greater than a diameter of the blank; and

at the output side, equal to or smaller than a desired minimum diameter of the spring wire;

forming the spring wire to have a diameter varying over a length thereof by moving the blank through the annular gap from the input side to the output side;

producing a nonlinear cylindrical spring by winding or coiling the spring wire.

2 . The method according to claim 1 , and further comprising operating the shaping device in a vertical alignment of the central longitudinal axis with the input side being an upper side and the output side being a lower side with respect to each other and moving the blank through the annular gap with assistance by gravity.

3 . The method according to claim 1 , and further comprising:

providing a winding machine having a rotatable winding rotor with a clamping device that opens according to the diameter of the spring wire, and a stationary tool; and

clamping one end of the spring wire to the rotatable winding rotor and winding the spring wire around the rotatable winding rotor against the stationary tool.

4 . The method according to claim 1 , and further comprising winding or coiling the spring wire cylindrically with respect to an inner diameter, a central diameter, or an outer diameter of the nonlinear cylindrical spring.

5 . The use according to claim 1 , and further comprising

forming the spring wire to have the diameter varying over the length thereof in accordance with a spring load over the travel path to set a position of the actuator in the valve.

6 . The method according to claim 1 , and further comprising controlling a fuel mass flow or fuel pressure with the valve.

7 . The method according to claim 1 , wherein the annular gap tapers conically.

8 . A method for producing a valve, comprising;

producing a nonlinear cylindrical spring, the method of producing comprising:

providing a blank of wire to be formed into a spring wire, the blank having a constant diameter over a length thereof;

providing a shaping device configured as a drum roller including:

an inner rotor rotatable about a central longitudinal axis and having an outer lateral surface;

an outer drum surrounding the inner rotor and being concentric with the inner rotor, the outer drum having an inner lateral surface facing the outer lateral surface;

an annular gap positioned between the outer lateral surface and the inner lateral surface, the annular gap having an input side and an output side and tapering continuously from the input side to the output side;

wherein a width of the annular gap, viewed in a radial direction, is:

 at the input side, greater than a diameter of the blank; and

 at the output side, equal to or smaller than a desired minimum diameter of the spring wire;

forming the spring wire to have a diameter varying over a length thereof by moving the blank through the annular gap from the input side to the output side;

producing the nonlinear cylindrical spring by winding or coiling the spring wire; and

installing the nonlinear cylindrical spring in the valve.

9 . A method for producing a spring for use in a valve for setting a travel path of an actuator, the method comprising:

providing a blank of wire to be formed into a spring wire, the blank having a constant diameter over a length thereof;

providing a shaping device including:

a first shaping die having a first shaping surface;

a second shaping die having a second shaping surface, the first shaping die and the second shaping die arranged such that the first shaping surface and the second shaping surface face one another with a gap therebetween,

the gap having an input side and an output side and the first shaping surface and the second shaping surface being configured to be non-parallel to one another such that the gap extends in a first direction extending from the input side to the output side and tapers continuously from the input side to the output side;

wherein a width of the gap is:

at the input side, greater than a diameter of the blank; and

at the output side, equal to or smaller than a desired minimum diameter of the spring wire;

forming the spring wire to have a diameter varying over a length thereof by moving the blank through the gap from the input side to the output side while simultaneously moving at least one of the first shaping die and the second shaping die with respect to the other of the first shaping die and the second shaping die in a direction transverse to the first direction;

producing a nonlinear cylindrical spring by winding or coiling the spring wire.