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

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.

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.