Device for setting the spring constant of a helical spring

1. A device for setting the spring constant of a helical spring for a wheel suspension of a motor vehicle, comprising:

spring plates and a helical spring mounted between said spring plates, said helical spring having turns with mutually different diameters including at least one small diameter turn and at least one large diameter turn;

said spring plates including an inner spring plate and an outer spring plate radially spaced apart from one another on a spring strut cylinder; and

said spring plates defining a first springing position of said helical spring, wherein said helical spring is braced with a small-diameter turn against said inner spring plate and said outer spring plate does not contact said helical spring, and a second springing position of said helical spring, wherein said helical spring is braced with a large diameter turn against said outer spring plate and said inner spring plate does not contact said helical spring.

2. The device according to claim 1 , wherein said spring plates further include a fixed, upper spring plate and wherein, in said first springing position, a lower end of said helical spring is supported with said small-diameter turn on said inner spring plate, and higher-lying, large-diameter spring turns of said helical spring are disposed in a free-springing relationship, between said upper spring plate and said inner spring plate.

3. The device according to claim 1 , wherein said inner spring plate is height-adjustably mounted in an axial direction on said spring strut cylinder or a guide element, and said outer spring plate is mounted in a stationary position on said spring strut cylinder.

4. The device according to claim 1 , wherein said inner spring plate and said outer spring plate are height-adjustably mounted in an axial direction on said spring strut cylinder or a guide element.

5. The device according to claim 1 , which comprises electromechanical or hydraulic actuating means for adjusting a height position of at least one of said inner and outer spring plates.

6. The device according to claim 1 , wherein, in said second springing position, said inner spring plate is adjusted downwardly in height such that a last lower small-diameter spring turn comes to be arranged free-lying and with a clearance from said inner spring plate, and an upper, large-diameter spring turn is supported on said outer spring plate.

7. The device according to claim 1 , wherein said helical spring is formed with a plurality of lower small-diameter spring turns and, in said second springing position, said lower small-diameter spring turns are arranged free-lying with respect to the inner spring plate.

8. The device according to claim 1 , wherein said inner spring plate is adjustable downwardly such that, in an event of a jouncing movement of a respective wheel, a clearance of a lower-most spring turn is maintained with respect to said inner spring plate.

9. The device according to claim 1 , wherein said inner spring plate is adjustable in height with respect to said outer spring plate to set a relatively harder spring constant in an event of compression movements of the wheel, and a relatively softer spring constant in a case of jouncing movements of the wheel.

10. The device according to claim 1 , wherein said inner spring plate and said outer spring plate are height-adjustable simultaneously with one another such that a compensation of the spring constants is achieved.

11. The device according to claim 1 , wherein a downward adjustment in height of said inner spring plate and said outer spring plate causes a lowering of the motor vehicle body.