LEAF SPRING DEVICE FOR A VEHICLE AND METHOD FOR PRODUCING SUCH A LEAF SPRING DEVICE

Abstract

A leaf spring device (1) for a vehicle having a first spring leaf (2) made of a fiber reinforced plastic and at least one further spring leaf (3). The first spring leaf (2) and the further spring leaf (3) interact with one another to implement a progressive suspension. The first spring leaf (2) has a receiving space (4) and the further spring leaf (3) is arranged in the receiving space (4) so as to implement the progressive suspension and/or to increase stability when using such a leaf-spring device (1).

Claims

1-14. (canceled)

15. A leaf-spring device for a vehicle, the leaf-spring device comprising: a first spring leaf (2), at least one further spring leaf (3), the first spring leaf (2) and the further spring leaf (3) interacting to implement a progressive suspension, the first spring leaf (2) having a receiving space (4), and the further spring leaf (3) being arranged in the receiving space (4).

16. The leaf-spring device according to claim 15, wherein an elastic material (15) is arranged in the receiving space (4), between the first spring leaf (2) and the further spring leaf (3), and the elastic material (15) contacts an inner circumference (16) of the receiving space (4) and an outer circumference (17) of the further spring leaf (3).

17. The leaf-spring device according to claim 16, wherein the first spring leaf (2) is made of a first fiber-reinforced plastic and the further spring leaf (3) is made of a further fiber-reinforced plastic which differs from the first fiber-reinforced plastic, at least one of the first fiber-reinforced plastic, the further fiber-reinforced plastic and the elastic material is designed or selected to be matched for implementing a predetermined spring characteristic.

18. The leaf-spring device according to claim 16, wherein at least one of the first spring leaf, the further spring leaf (2) and the elastic material (15) are designed to implement at least one of a progressive suspension and a progressive spring characteristic, and starting from an unstressed state of the leaf-spring device (1), the elastic material (15) is at least one of increasingly deformed and compressed upon increasing spring load such that the further spring leaf (3) is increasingly stressed.

19. The leaf-spring device according to claim 16, wherein at least one of the further spring leaf (3) and the elastic material (15) is arranged completely within the first spring leaf (2), the receiving space (4) is designed as a cavity in the first spring leaf (2), and at least one of the further spring leaf (3) and the elastic material (15) is completely surrounded by the first spring leaf (2).

20. The leaf-spring device according to claim 15, wherein the receiving space (4) is a through hole and extends from a first side (5) of the first spring leaf (2) to a second side (6) of the first spring leaf (2) facing away from the first side (5) of the first spring leaf (2), and the receiving space (4) extends perpendicular to a vehicle vertical axis in a mounted state of the leaf-spring device (1) in the vehicle.

21. The leaf-spring device according to claim 15, wherein at least one of the first spring leaf (2) and the further spring leaf (3) is formed as a mirror image to a median plane (9), the median plane (9) extends either parallel or perpendicular to a longitudinal axis of the leaf-spring device (1), and the longitudinal axis of the leaf-spring device (1) extends through two end fastening devices facing away from each other for fastening the leaf-spring device (1) to at least one of a vehicle carrier and a vehicle body.

22. The leaf-spring device according to claim 15, wherein at least one of the first spring leaf (2), the further spring leaf (3) and the receiving space (4) has either a curved or arcuate shape in an unstressed state of the leaf-spring device (1).

23. The leaf-spring device according to claim 15, wherein the receiving space (4), in an unstressed state of the leaf-spring device(1), has a convex curved inner side (18) and a concave curved inner side (19), the convex curved inner side (18) and the concave curved inner side (19) extend in a longitudinal direction of the first spring leaf (2), and the convex curved inner side (18) and the concave curved inner side (19) are at least one of arranged opposite from each other and facing each other.

24. The leaf-spring device according to claim 23, wherein two end areas (12, 13) of the further spring leaf (3) facing away from each other are arranged at a shorter distance from the concave curved inner side (19) than from the convex curved inner side (18) in an unstressed state of the leaf-spring device (1), a first end area (12) of the further spring leaf (3) faces a first end (7) of the first spring leaf (2) and a second end area (13) of the further spring leaf (3) faces a second end (8) of the first spring leaf (2).

25. The leaf-spring device according to claim 23, wherein a central region (14) of the further spring leaf (3), in an unstressed state of the leaf-spring device (1), is arranged at a shorter distance from the convex curved inner side (18) than to the concave curved inner side (19), and the central area (14) is arranged centrally between two end areas (12, 13) of the further spring leaf (3).

26. A method for manufacturing a leaf-spring device for a vehicle, the leaf-spring device has a first spring leaf (2) and at least one further spring leaf (3), the first spring leaf (2) and the further spring leaf (3) interact with one another to implement a progressive suspension, the first spring leaf (2) has a receiving space (4) and the further spring leaf (3) is arranged in the receiving space (4), the method comprising: manufacturing a first spring leaf (2) and at least one further spring leaf (3), and interacting the first spring leaf (2) with the further spring leaf (3) to implement at least one of a progressive suspension and spring characteristic, providing the first spring leaf (2) with a receiving space (4), and arranging the further spring leaf (3) in the receiving space (4).

27. The method according to claim 26, further comprising arranging an elastic material (15) in the receiving space and between the first spring leaf (2) and the further spring leaf (3) such that the first spring leaf (2), the further spring leaf (3) and the elastic material (15) are manufactured in at least one of a layered form and a layer-like form and the leaf-spring device (1) is at least one of constructed and manufactured in at least one of layers and layer-like.

28. The use of such a leaf spring device (1) according to claim 15 as either a longitudinal leaf spring or a transverse leaf spring in a chassis of either a vehicle or a motor vehicle.

29. A leaf-spring device for a vehicle, the leaf-spring device comprising: a first spring leaf defining a longitudinal axis and having a longitudinally extending through hole that forms a receiving space, and the receiving space laterally spanning through the first spring leaf; and at least one further spring leaf being arranged within the receiving space such that the first spring leaf and the further spring leaf interact with one another to implement a progressive suspension.

30. The leaf-spring device according to claim 29, wherein an elastic material is arranged in the receiving space between the first spring leaf and the further spring leaf, and the elastic material contacting an inner circumference of the receiving space and an outer circumference of the further spring leaf.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Below, the invention will be explained in more detail with reference to the figures. The same reference numerals refer to the same, similar or functionally identical components or elements., In the figures:

[0029] FIG. 1 shows a perspective view of the leaf-spring device according to the invention;

[0030] FIG. 2 shows a side view of the leaf-spring device according to the invention shown in FIG. 1,

[0031] FIG. 3 shows a detail of the leaf-spring device according to the invention shown in FIG. 2, and

[0032] FIG. 4 shows a cross section of the leaf-spring device according to the invention shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] FIG. 1 shows a perspective view of a leaf-spring device 1 according to the invention. The leaf-spring device 1 has a first spring leaf 2 and a further spring leaf 3. In this embodiment, the further spring leaf 3 is formed as a second spring leaf. In all, the leaf-spring device 1 thus has two spring leaves, namely the first spring leaf 2 and the further spring leaf 3. The first spring leaf 2 and the further spring leaf 3 are each formed of a fiber-reinforced plastic, in this embodiment of a glass-fiber reinforced plastic. The further spring leaf 3 is shorter than the first spring leaf 2 in relation to the longitudinal extent of the leaf-spring device 1. Both the first spring leaf 2 and the further spring leaf 3 have a curved shape according to this example, in particular in an unstressed state. The further spring leaf 3 is arranged in a receiving space 4 of the first spring leaf 2. Thus, the further spring leaf 3 is disposed within the first spring leaf 2 and integrated into the first spring leaf 2.

[0034] In this embodiment, the receiving space 4 is formed as a through hole in the first spring leaf 2. The receiving space 4 extends from a first side 5 of the first spring leaf to a second side 6 of the first spring leaf 2 facing away from the first side 5. In this exemplary embodiment, the leaf-spring device 1 is formed as a longitudinal leaf spring. Thus, the receiving space 4 or a longitudinal axis of the through opening 4 forming the receiving space extends transversely or perpendicular to a vertical vehicle axis in a mounted state of the leaf-spring device 1 in a vehicle and/or in a chassis not shown here.

[0035] The first leaf spring 2 has a first end 7 and a second end 8 facing away from the first end 7. The two ends 7, 8 are formed as free ends. The leaf-spring device 1 can be fastened to a vehicle beam, vehicle frame and/or vehicle body by means of two attachment devices arranged opposite from each other and arranged in the area of the end 7 or 8 and not shown here.

[0036] FIG. 2 shows a side view of the leaf-spring device 1 according to the invention as shown in FIG. 1. The spring leaf 2, the further spring leaf 3 and the receiving space 4 are formed as mirror images to a center plane 9. In an assembled state of the leaf-spring device 1, the center plane 9 is oriented vertically. In this exemplary embodiment the center plane 9 furthermore extends perpendicular to the longitudinal extent of the leaf-spring device 1. Alternatively, a center plane may extend exclusively in parallel to the longitudinal extent of the leaf-spring device 1. In the formation of the leaf-spring device 1 as a longitudinal leaf spring, in the mounted state the center plane 9 also extends perpendicular to a longitudinal axis of a vehicle. Furthermore, the first leaf-spring device 1 has a curved shape. As a result, the leaf-spring device 1 or the first spring leaf 2 has a concave outer side 10 and a convex outer side 11.

[0037] The further spring leaf 3 has a first end area 12 and a second end area 13 facing away therefrom. In this case, the first end area 12 faces the first end 7 of the first spring leaf 2 and the second end area 13 faces the second end 8 of the first spring leaf 2, but in each case is spaced apart from this end 7, 8, The further spring leaf 3 has a central area 14 in the center between the two end areas 12, 13.

[0038] An elastic material 15 is arranged between the first spring leaf 2 and the further spring leaf 3 In this exemplary embodiment, the elastic material 15 is formed as an elastomeric material. The elastic material 15 contacts an inner circumference 16 of the receiving space 4 on the one hand and an outer circumference 17 of the further spring leaf 3 on the other hand.

[0039] The inner circumference 16 is formed by means of a convex curved inner side 18, a concave curved inner side 19 and end-side sections 20, 21 of the receiving space 4 interconnecting the two inner sides 18, 19.

[0040] FIG. 3 shows a detail of the side view of the leaf-spring device 1 according to the invention as shown in FIG. 2. In the unstressed state of the leaf-spring device 1 shown here, the first end area 12 of the further spring leaf 3 is arranged at a shorter distance from the concave curved inner side 19 than from the convex curved inner side 18. An analogous arrangement results for the end area 13 formed as a mirror image as shown in FIG. 2.

[0041] Furthermore, in the unstressed state of the leaf-spring device 1 shown here, the central area 14 is arranged at a shorter distance from the convex curved inner side 18 than from the concave curved inner side 19. As a result, more elastic material 15 is arranged in the areas having greater distance between the outer circumference 17 of the further spring leaf 3 and the inner circumference 16 of the first spring leaf 2 than in the regions having smaller distances.

[0042] FIG. 4 shows a cross section 4-4 of the leaf-spring device according to the invention 1 as shown in FIG. 3. It can be clearly seen that the receiving space 4 is formed as a through hole extending from the first side 5 to the second side 6 of the first spring leaf 2. In this exemplary embodiment, the receiving space is completely filled by the further spring leaf 3 and the elastic material 15, In this case, the further spring leaf 3 and the elastic material 15 are flush with the sides 5 and 6, respectively. Alternatively, the elastic material can have an inwardly facing or concave depression.

[0043] Starting from the unstressed state as shown in FIGS. 1 to 4, the elastic material 15 is increasingly deformed with increasing spring bad and then successively or simultaneously the further spring leaf is increasingly stressed 3. There, the spring bad from the convex outer side 10 acts in the direction of the concave outer side 11. In an assembled state of the leaf-spring device 1, the spring bad is directed in the vertical direction from bottom to top or in the direction of the vertical axis of the vehicle.

[0044] Due to the interaction of the first spring leaf 2, the further spring leaf 3 and the elastic material 15, the leaf-spring device 1 can be used to implement a progressive suspension or progressive spring characteristic. in this case, due to the elastic material 15 between the two spring leaves 2, 3, damage to the spring leaves 2, 3, formed from a fiber-reinforced plastic is prevented.

[0045] For a desired suspension behavior of the leaf-spring device 1, the first spring leaf 2, the further spring leaf 3, the receiving space 4 and/or the elastic material 15 can be suitably formed or adapted. This design or adaptation may relate to the shape, contour or material properties.

REFERENCE NUMERALS

[0046] 1. leaf-spring device [0047] 2. first spring leaf [0048] 3. further spring leaf [0049] 4. receiving space [0050] 5. first side [0051] 6. second side [0052] 7. first end [0053] 8. second end [0054] 9. center plane [0055] 10. concave outer side [0056] 11. convex outer side [0057] 12. first end area [0058] 13. second end area [0059] 14. central area [0060] 15. elastic material [0061] 16. inner circumference [0062] 17. outer circumference [0063] 18. convex inner side [0064] 19. concave inner side [0065] 20. end-side section [0066] 21. end-side section